It is currently Sun Dec 21, 2014 4:28 am





Post new topic Reply to topic  [ 39 posts ] 
Building 300 for towing 
Author Message
Registered User

Joined: Tue Oct 05, 2010 2:05 am
Posts: 7
Post Building 300 for towing
I'm going to find a carbed 300 to drop into my '69 f250 4x4 restoration. It will be my daily driver and race truck hauler. Truck weighs 5,200 and trailer will weight about 6,000. The 300 has to be able to tow this without struggling. I also need good milage, something like 18mpg's would be nice.

What carb/intake/exhaust/cam/etc. is best for my application without sacrificing gas milage??

Thanks!

_________________
1969 f250 4x4 Restored, daily driver and heavy hauler.


Wed Oct 06, 2010 2:08 pm
Profile
VIP Member

Joined: Mon Jun 14, 2004 3:42 pm
Posts: 876
Location: Helena, MT. pop. enough
Post Re: Building 300 for towing
1971ford wrote:
....... a carbed 300 ...... Truck weighs 5,200 .. trailer about 6,000 ... able to tow ... without struggling. I need milage, ... 18mpg's would be nice. What carb/intake/exhaust/cam/etc. is best for my application without sacrificing gas milage?? Thanks!


This question reminds me of the sign that asked. "Do you want it fast? Do you want it good? Do you want it cheap? You only get to pick one, two at the most" :hmmm:

The 300 will move the weight just fine, even in stock form, but it wont be fast. Some would mistake the lack of speed as "struggling". Even in stock form a 300 will not deliver 18mpg at a 12K CGVWR.

A person could (some have) spend $10K on the engine and make it faster, but it probably wont get past 10-12mpg for mileage in hauling/towing mode. You could get a same or better result from a $5K 460.

I guess what I'm trying to say is, figure out which of the criteria you mentioned is THE most important one for you and "Pick One". Then we can be more helpful and accurate with our advice.

None of what I have said above is intended to be "snarky" in any way. We really do want to answer your questions. Others here will be along shortly to weigh in.

_________________
1 "76" F150 RC, LB, 2WD, 300, NP435, 9" open 3.00, special order 2-76/Delivered 4-76. Still "new".

1 "73-79" F150 RC/SS/SB/4WD, "84"-300, T18, NP205, 9" open 3.50, Dana 44 3.50 open, Offy DP, Holley 470, EFI + single 2.5" exhaust. Gathered from 15+ donor/parts trucks. "Fubar". Runs good, safe, still needs details/project continues.


Wed Oct 06, 2010 4:45 pm
Profile
Global Moderator
User avatar

Joined: Sat Oct 18, 2003 10:49 pm
Posts: 5502
Location: The Great state of Ohio!!
Post Re: Building 300 for towing
luckyman speaks the truth.

18MPG not feeling like its struggling pulling 12K lbs = diesel

I can't blame ya for shooting for the stars though.

_________________
OAPSE Union Member

Real men don't wear Bowties
When it come to engines If its .001 loose nobody knows, But if its .001 too tight EVERYBODY KNOWS!!
80 bronco FUV (farm utility vehicle)300 T-18 3.50s EFI head, offy C dual plenum, 500 edel carb, 1.7 roller rockers, Crane 260 cam EFI Exh


Wed Oct 06, 2010 5:47 pm
Profile
FSP Moderator

Joined: Fri May 16, 2003 10:25 pm
Posts: 6274
Location: Careywood, Idaho
Post Re: Building 300 for towing
1971ford wrote:
.......has to be able to tow this without struggling. I also need good milage, something like 18mpg's would be nice......


Dream on my friend, dream on......... :D
Joe

_________________
74 F-350 300-6, EFI manifolds into single exhaust, Carter YF, T-18B, Dana70 w/4.11, Flatbed dually w/dump bed. Great farm truck!
Image


Wed Oct 06, 2010 7:26 pm
Profile
VIP Member
User avatar

Joined: Sat Oct 21, 2006 9:17 pm
Posts: 2451
Location: Spokane, WA
Post Re: Building 300 for towing
viewtopic.php?f=2&t=62982

Read that post. Keep in mind that I am a trucker. I am used to the "dragon fly" (drag uphill and fly down hill) nature of moving heavy loads. Moving 11,200 lbs. gross weight without "struggling" at 18 mpg just isn't going to happen with a 300 I6.

_________________
'83 F150 300, 0.030 over, Offy DP, Holley 4160/1848-1 465 cfm, Comp Cam 260H. P/P head, EFI exhaust manifolds, Walker Y Pipe, Super Cat, Turbo muffler, Recurved DSII, Mallory HyFire 6a, ACCEL Super Stock Coil, Taylor 8mm Wires, EFI plugs.


Wed Oct 06, 2010 8:02 pm
Profile
Registered User
User avatar

Joined: Sat Jan 31, 2004 10:01 pm
Posts: 420
Post Re: Building 300 for towing
71

Did you mean 18 Mpg empty but still able to pull your trailer when needed? If so, I believe the best shot would be a 300 with a turbo. Power when you need it, decent mileage if you stay off the gas. I've considered similar for my one ton.

Good luck
Worken2much

_________________
Rule #1. Six Cylinder Racers Have Longer Cranks.
Rule #2. Unless your given name is Richard...don't be a dick.


Thu Oct 07, 2010 8:28 am
Profile
Registered User
User avatar

Joined: Sun Nov 22, 2009 5:32 pm
Posts: 420
Location: Twilight zone, WA
Post Re: Building 300 for towing
I took 71Ford's original post to mean 18 mpg empty. That is theoreticaly possible with a full size 4x4 truck. The rear end ratio will be a crucial decision. 4.11 gears - great for towing, horrible for mileage. 3.08 gears (like mine) - great for mileage, not so good for towing 6K lb. trailer.

_________________
1995 F-150, 300-6, 4x4, ex-cab, sb, 3.08 5-speed, 2 1/2 in. exhaust w/flowmaster 50, MSD + ignition upgrades, canopy, 171,000 + miles Gone but not forgotten: 1965 F-100 240 3spd lwb "the green hornet"; 1991 f-150 300 5sp 2wd sb, 1960 F-250 4x4, 223 six, 4sp with wrap-around rear window, two-tone paint.
Tow vehicle: 2012 F-250 4x4 6.7 diesel XLT s/c lwb 20+mpg


Thu Oct 07, 2010 10:26 am
Profile
Registered User

Joined: Wed Jan 13, 2010 11:42 pm
Posts: 338
Post Re: Building 300 for towing
Something completely different: An injected diesel with a hydrogen cell would fit your needs. I've read about some amazing things being done with them. Research and money are the keys.


Thu Oct 07, 2010 2:19 pm
Profile
VIP Member
User avatar

Joined: Sat Oct 21, 2006 9:17 pm
Posts: 2451
Location: Spokane, WA
Post Re: Building 300 for towing
I get 18+ mpg when empty holding at a maximum speed of 62 mph.

_________________
'83 F150 300, 0.030 over, Offy DP, Holley 4160/1848-1 465 cfm, Comp Cam 260H. P/P head, EFI exhaust manifolds, Walker Y Pipe, Super Cat, Turbo muffler, Recurved DSII, Mallory HyFire 6a, ACCEL Super Stock Coil, Taylor 8mm Wires, EFI plugs.


Thu Oct 07, 2010 3:26 pm
Profile
Registered User
User avatar

Joined: Tue Jan 06, 2004 12:16 pm
Posts: 298
Location: Sussex County, DE
Post Re: Building 300 for towing
Before my original rear axle quit at 280,000 miles, I had 3.08 gearing. With my NP-435 trans, I used to get 21 MPG at 55 MPH. At 60 it dropped to 19.5, at 65 MPH, it dropped further to 17, and at 70 it dropped to 16.3 PG according to my logs. When the axle ratio changed to 3.73 (because I needed an axle to swap in cheap and fast, and that was what was available), the mileage dropped considerably. I now get 14.5 MPG at 55, and about 13 at 65. I don't do 70 anymore, because I cringe at the thought of winding the engine to 3,000 RPM for long stretches. I am in the midst of planning a 4wd conversion, so I am living with it this way for now, but I am hoping to either go to 3.08 gearing again, or go to 3.73 front and rear with an overdrive manual. The problem is I have to give up my 2wd only NP-435. Hopefully I can replace it with another NP-435 or a T-18/T-19 when I go 4wd. This setup would be ideal with 3.08 gearing. If not, the I might do a C6 with a low stall converter and 3.08 gears. If I find a ZF, I'll likely stay 3.73. For what it's worth, my truck is a fat girl, weighing in at 5,280 lbs before I place my husky self inside it. I have towed a 4,500lb Lincoln Town Car on a 3,000 LB trailer, and a bed filled with 1,200 lbs of car parts with the 3.08 gearing, (that's 15,830 lbs total) and the engine pulled it just fine. I wouldn't say it struggled, but you did know that the weight was there. I had to floor it in 4th gear to maintain 55 MPH on some grades, but it never dropped below 55 even while crossing the new Saint George's bridge over the C&D canal in Delaware. I also only needed to start out in 1st once, on a hard uphill grade coming out of PA, where the car was located. Under that load it gave me an impressive 11.7 MPG. This engine won't give you an effortless feeling like a modern diesel might, (or a 460 might for that matter) but it never seems like it's struggling when moving that much weight. Working hard, but not struggling. It just chugs away happily, enjoying it’s work.

_________________
"The Argo" 321,000 miles and counting
It was a 1996 2wd Ford F-150 300ci Inline 6 NP-435 2.73:1 8.8" Rear;
It is a 1996 4wd Ford F-150 300ci Inline 6, C6 Transmission, 3.55:1 axles (limited slip in rear), BW 1356 manual shift transfer case with manual hubs
"Ah Ha Ha Ha Ha Ha! I Swear! Tractors is so dumb!" - Mater


Thu Oct 07, 2010 4:01 pm
Profile
Registered User
User avatar

Joined: Sun Nov 22, 2009 5:32 pm
Posts: 420
Location: Twilight zone, WA
Post Re: Building 300 for towing
argo, thanks for the interesting post.
Out West, in the Cascades and Rockies, we have some major league grades, and the grades plus the elevation might influence the situation of whether 3.08 rear and stock 300 engine are going to cut it for a 10-15 K lb load. Something for 71Ford to consider. (Harte3 has an RV cam, something I occasionally wish I had)

I have a heavy 4x4 truck too and climb mtns in the slow lane by choice, sometimes by necessity. I hate to drive with a heavy foot. Last weekend, round trip Olympic Peninsula to Spokane and back over the Cascades, 20.8 mpg for the trip, speeds under 65 except downhill, headwinds all the way Eastbound. Steepest grades over the passes taken in third at 45 mph ~2500 rpm. Good enough for me . . . .

_________________
1995 F-150, 300-6, 4x4, ex-cab, sb, 3.08 5-speed, 2 1/2 in. exhaust w/flowmaster 50, MSD + ignition upgrades, canopy, 171,000 + miles Gone but not forgotten: 1965 F-100 240 3spd lwb "the green hornet"; 1991 f-150 300 5sp 2wd sb, 1960 F-250 4x4, 223 six, 4sp with wrap-around rear window, two-tone paint.
Tow vehicle: 2012 F-250 4x4 6.7 diesel XLT s/c lwb 20+mpg


Thu Oct 07, 2010 6:00 pm
Profile
FSP Moderator

Joined: Fri May 16, 2003 10:25 pm
Posts: 6274
Location: Careywood, Idaho
Post Re: Building 300 for towing
Lazy JW wrote:
1971ford wrote:
.......has to be able to tow this without struggling. I also need good milage, something like 18mpg's would be nice......


Dream on my friend, dream on......... :D
Joe

I am not aware of ANY gasoline fueled engine capable of meeting this goal.
Feel free to enlighten me, I too would like to accomplish this feat.
Joe

_________________
74 F-350 300-6, EFI manifolds into single exhaust, Carter YF, T-18B, Dana70 w/4.11, Flatbed dually w/dump bed. Great farm truck!
Image


Thu Oct 07, 2010 6:52 pm
Profile
Registered User

Joined: Wed Jan 13, 2010 11:42 pm
Posts: 338
Post Re: Building 300 for towing
Harte3 wrote:
I get 18+ mpg when empty holding at a maximum speed of 62 mph.



Harte3--Excellent mileage. Didn't I read in one of your posts, that AB calculated your rear gears at 2.72? So, if I put a ZF in my truck, with my 3.31 rears, your fourth would still be taller than my fifth. ARR!


Thu Oct 07, 2010 10:38 pm
Profile
VIP Member
User avatar

Joined: Fri Nov 08, 2002 6:54 pm
Posts: 8004
Location: Copley, OH
Post Re: Building 300 for towing
3.31 x 0.76 = 2.52 which is substantially taller than 2.73

_________________
1996 F-150 (tow missile)
1993 Mustang 5.0 (hot rod and auto-x monster)
1982 Tiga Formula Ford (SCCA racecar)
2013 Hyundai Elantra Coupe (daily driver)


Thu Oct 07, 2010 11:15 pm
Profile
Registered User
User avatar

Joined: Sun Nov 22, 2009 5:32 pm
Posts: 420
Location: Twilight zone, WA
Post Re: Building 300 for towing
engine/truck meeting 71Ford's goals -
how 'bout 2010 F-150 with 5.4L v8
310HP
365 ft/lb Tq at 3500 rpm
EPA 20 mpg hwy.

engine spec numbers on the 2011 F-150 look even better
365 hp
420 ft/lbs tq at 2500 rpm
3.5L V6 ecoboost

If were going to stick with a stock or modded 300, perhaps we need to define "struggling".

_________________
1995 F-150, 300-6, 4x4, ex-cab, sb, 3.08 5-speed, 2 1/2 in. exhaust w/flowmaster 50, MSD + ignition upgrades, canopy, 171,000 + miles Gone but not forgotten: 1965 F-100 240 3spd lwb "the green hornet"; 1991 f-150 300 5sp 2wd sb, 1960 F-250 4x4, 223 six, 4sp with wrap-around rear window, two-tone paint.
Tow vehicle: 2012 F-250 4x4 6.7 diesel XLT s/c lwb 20+mpg


Fri Oct 08, 2010 10:37 am
Profile
VIP Member
User avatar

Joined: Sat Oct 21, 2006 9:17 pm
Posts: 2451
Location: Spokane, WA
Post Re: Building 300 for towing
Well, I wondered about the calculation of the gear ratio as it seemed a bit tall to me. The calculations were made based on the rpm/speed/tire size...235/75R15...30 mph at 1000 rpm, 60 mph at 2000 rpm. Speedometer/odometer is correct verified over 100 miles against highway mile markers. The tach might be off but I don't think so. I had it in the shop last week for service on the transmission and rear end and one of the numbers on the axle tag is an 08. BTW, on my last trip to the coast I pushed to 65+ mph but not over 70 and mpg dropped to just a little over 17. Speed does make a difference. When on holiday with about 4 hours +/- overall driving time loaded and towing 8960# gvw (weighed on a CAT scale) it got a mpg of 12+. Did it "struggle"? Somewhat of a subjective term that may defy definition...but in my opinion, no. An approximate 6% grade in third gear holding 1100-1200 rpm without over heating in my opinion is not "struggling." On a solid 7% grade like Whitebird or Lewiston Hill I have no doubt it would pull just fine...in second gear. Is that "struggling"? Only if one mistakenly thinks they can pull loads like that on grades like that in high gear with a 300.

_________________
'83 F150 300, 0.030 over, Offy DP, Holley 4160/1848-1 465 cfm, Comp Cam 260H. P/P head, EFI exhaust manifolds, Walker Y Pipe, Super Cat, Turbo muffler, Recurved DSII, Mallory HyFire 6a, ACCEL Super Stock Coil, Taylor 8mm Wires, EFI plugs.


Fri Oct 08, 2010 11:56 am
Profile
VIP Member
User avatar

Joined: Fri Nov 08, 2002 6:54 pm
Posts: 8004
Location: Copley, OH
Post Re: Building 300 for towing
Harte3 wrote:
Well, I wondered about the calculation of the gear ratio as it seemed a bit tall to me. The calculations were made based on the rpm/speed/tire size...235/75R15...30 mph at 1000 rpm, 60 mph at 2000 rpm. Speedometer/odometer is correct verified over 100 miles against highway mile markers. The tach might be off but I don't think so.


235/75R15s roll at about 720-722 per mile. At 60 MPH that's also 720-722/minute

With a 1:1 top gear and 2.73s that's 1966-1971 RPM
With a 1:1 top gear and 3.08s that's 2218-2224 RPM

I'd bet on the 2.73s and a 30 RPM error either in the tach or in reading it.

_________________
1996 F-150 (tow missile)
1993 Mustang 5.0 (hot rod and auto-x monster)
1982 Tiga Formula Ford (SCCA racecar)
2013 Hyundai Elantra Coupe (daily driver)


Fri Oct 08, 2010 1:46 pm
Profile
VIP Member
User avatar

Joined: Sat Oct 21, 2006 9:17 pm
Posts: 2451
Location: Spokane, WA
Post Re: Building 300 for towing
I'm thinking a Tach error as it will read differently by 100-200 rpm for the same speed on different occasions.

_________________
'83 F150 300, 0.030 over, Offy DP, Holley 4160/1848-1 465 cfm, Comp Cam 260H. P/P head, EFI exhaust manifolds, Walker Y Pipe, Super Cat, Turbo muffler, Recurved DSII, Mallory HyFire 6a, ACCEL Super Stock Coil, Taylor 8mm Wires, EFI plugs.


Fri Oct 08, 2010 4:40 pm
Profile
Registered User
User avatar

Joined: Sat Nov 21, 2009 12:39 am
Posts: 634
Location: Anchorage, Alaska
Post Re: Building 300 for towing
I find factory tachometers are not a very good means of predicting engine speed at a resolution under 50 RPM. I have had a scan tool, Ford RPM control, and factory tach all read within 10 to 20 RPM of each other before.

_________________
1974 Ford F-250, Turbocharged and Intercooled 300, Megasquirt Fuel Injection and Ignition control, EDIS, 7.8:1 compression, Harland Sharp roller rockers, Crane 284/272 cam, mild port/polish carb head - 194/1.60 valves, EFI manifolds into turbo - 3.5 inch to muffler - dual 3 inch out the back.


Sun Oct 10, 2010 2:14 pm
Profile WWW
Registered User
User avatar

Joined: Tue Jan 06, 2004 12:16 pm
Posts: 298
Location: Sussex County, DE
Post Re: Building 300 for towing
A while back, (2005 I believe) I had thought about converting my truck to 4WD (I am again, but that's another matter). I ran some scenarios with different transmissions and Drag Sim to see what different transmissions would perform like. I found it today while cleaning up some files on my computer, and thought they would be of interest here. The engine is a stock, 160 HP EFI 300 six, in a 5300 lb truck. There were two tests, one unloaded, the other loaded with an 8,000 lb trailer. I had to take some creative license with the numbers to get the loaded estimates: The Drag Sim program would not accept my GCW calculation of 13,300lbs. It was above it's weight limit of 10,000 lbs. So instead, I took 5,300 lbs and divided it by 13,300 lbs, and got .398, which I rounded to .4, or 40%, and reduced the torque rating at each point on the curve to 40% of it's value to "add" the load to the simulated truck (or see what a 5,300 lb F-150 would run like with only 64 HP). The results were actually quite surprising! FYI, the dyno sheet I used for the stock EFI 300 six's torque curve was provided several years ago by SilverStreak over on FTE forums. Here are the numbers.

Unloaded F-150: 5,300lb curb weight, 300 ci Six Cylinder, stock LT 235-75-R15 (29") Tires.

NP-435 3.08 Rear Axle Ratio (2nd-4th Gears Only) 1,200 RPM Launch

0-60: 15.529 sec

¼ Mile: 20.417 sec @ 66.2 MPH



C6 1,800 RPM Stall 3.08 Ratio

0-60: 14.570 sec

¼ Mile: 19.990 @ 68.0 MPH



M5OD 3.08 Ratio 1,200 RPM Launch

[b]0-60:
13.862 sec

¼ Mile: 19.935 sec @ 69.2 MPH


M5OD 3.73 Ratio 1,200 RPM Launch

[b]0-60:
15.333 sec

¼ Mile: 20.912 sec @ 69.4 MPH


Loaded F-150: 5,300 LB curb weight plus 8,000 Lb Trailer, 13,300 Lbs GCW, 300 ci Six Cylinder


NP-435 3.08 Ratio (All 4 Gears) 1,200 RPM Launch

0-60: N.A. sec

¼ Mile: 28.440 sec @ 49.3 MPH


C6 1,800 RPM Stall 3.08 Ratio

0-60: N.A. sec

¼ Mile: 29.054 sec @ 46.7 MPH



M5OD 3.08 Ratio 1,200 RPM Launch

0-60: N.A. sec

¼ Mile: 28.697 sec @ 49.1 MPH


M5OD 3.73 Ratio 1,200 RPM Launch

0-60: N.A. sec

¼ Mile: 28.148 sec @ 50.3 MPH


Now before I get hate mail about the M5OD not holding up under this strain, just relax and realize that I know that, and this is for comparative purposes only. I didn't have the specs for the ZF 5 speed and it's ratios. The C6 and NP-435 were my choices, because durability was also high on my list of priorities. Also, IIRC, the numbers didn't significantly change between the 3.08 and 3.73 range, and actually the truck was significantly slower when unloaded with the deeper gearing. Look at the unloaded M5OD acceleration as an example: The 3.08 ratio truck was nearly 1 second faster in the 1/4 mile and 1.5 seconds faster 0-60.

_________________
"The Argo" 321,000 miles and counting
It was a 1996 2wd Ford F-150 300ci Inline 6 NP-435 2.73:1 8.8" Rear;
It is a 1996 4wd Ford F-150 300ci Inline 6, C6 Transmission, 3.55:1 axles (limited slip in rear), BW 1356 manual shift transfer case with manual hubs
"Ah Ha Ha Ha Ha Ha! I Swear! Tractors is so dumb!" - Mater


Last edited by argo on Sun Oct 10, 2010 4:45 pm, edited 1 time in total.



Sun Oct 10, 2010 4:25 pm
Profile
VIP Member
User avatar

Joined: Sat Oct 21, 2006 9:17 pm
Posts: 2451
Location: Spokane, WA
Post Re: Building 300 for towing
@Emerald: My Tach is a Summit "special"...Not one of the better grades but it has served it's purpose.

_________________
'83 F150 300, 0.030 over, Offy DP, Holley 4160/1848-1 465 cfm, Comp Cam 260H. P/P head, EFI exhaust manifolds, Walker Y Pipe, Super Cat, Turbo muffler, Recurved DSII, Mallory HyFire 6a, ACCEL Super Stock Coil, Taylor 8mm Wires, EFI plugs.


Sun Oct 10, 2010 4:44 pm
Profile
Registered User
User avatar

Joined: Sat Nov 21, 2009 12:39 am
Posts: 634
Location: Anchorage, Alaska
Post Re: Building 300 for towing
Yeah, usually theres a threshold between a tach serving a purpose and actually giving you an accurate reading for data compilation and usage. That threshold usually ends up being between street and racing applications.

_________________
1974 Ford F-250, Turbocharged and Intercooled 300, Megasquirt Fuel Injection and Ignition control, EDIS, 7.8:1 compression, Harland Sharp roller rockers, Crane 284/272 cam, mild port/polish carb head - 194/1.60 valves, EFI manifolds into turbo - 3.5 inch to muffler - dual 3 inch out the back.


Sun Oct 10, 2010 6:31 pm
Profile WWW
Global Moderator
User avatar

Joined: Sat Oct 18, 2003 10:49 pm
Posts: 5502
Location: The Great state of Ohio!!
Post Re: Building 300 for towing
Emerald 74 4X4 wrote:
Yeah, usually theres a threshold between a tach serving a purpose and actually giving you an accurate reading for data compilation and usage. That threshold usually ends up being between street and racing applications.


And I'd also think that 50 rpm matters much more between 450 and 500 than it does at 4450 and 4500 rpm

_________________
OAPSE Union Member

Real men don't wear Bowties
When it come to engines If its .001 loose nobody knows, But if its .001 too tight EVERYBODY KNOWS!!
80 bronco FUV (farm utility vehicle)300 T-18 3.50s EFI head, offy C dual plenum, 500 edel carb, 1.7 roller rockers, Crane 260 cam EFI Exh


Sun Oct 10, 2010 6:34 pm
Profile
Registered User
User avatar

Joined: Sat Nov 21, 2009 12:39 am
Posts: 634
Location: Anchorage, Alaska
Post Re: Building 300 for towing
Yeah, good point. I suppose it depends on how it is offset. Is it 50 RPM off at 500 RPM (10%) which translates to 500 RPM off at 5000 RPM (10%). Or is it a constant 50 RPM throughout? I don't really know how tachometers normally fail to cause erroneous readings. The one on my VW Jetta works fine sometimes, then sometime it will start stepping up, higher and higher, then work normally in the 7000 RPM range. Then you shut the key off and it flutters back down to the parked position.

_________________
1974 Ford F-250, Turbocharged and Intercooled 300, Megasquirt Fuel Injection and Ignition control, EDIS, 7.8:1 compression, Harland Sharp roller rockers, Crane 284/272 cam, mild port/polish carb head - 194/1.60 valves, EFI manifolds into turbo - 3.5 inch to muffler - dual 3 inch out the back.


Sun Oct 10, 2010 7:00 pm
Profile WWW
Global Moderator
User avatar

Joined: Sat Oct 18, 2003 10:49 pm
Posts: 5502
Location: The Great state of Ohio!!
Post Re: Building 300 for towing
Factory 5.0l stang tachs years ago I heard were close to accurate at 1k rpm , put the needle on 5500rpm and you were really turing 5000.
I also heard this was done on purpose. I heard it was because of the averge age of the buyers was so low.

_________________
OAPSE Union Member

Real men don't wear Bowties
When it come to engines If its .001 loose nobody knows, But if its .001 too tight EVERYBODY KNOWS!!
80 bronco FUV (farm utility vehicle)300 T-18 3.50s EFI head, offy C dual plenum, 500 edel carb, 1.7 roller rockers, Crane 260 cam EFI Exh


Sun Oct 10, 2010 10:33 pm
Profile
Registered User

Joined: Tue Oct 05, 2010 2:05 am
Posts: 7
Post Re: Building 300 for towing
Wow, lots of info, thanks guys...
When i said 18mpg's, i meant unloaded, i don't care about mpg's when loaded
The gears are 4.10's, but instead of swapping gears out I'll change tire sizes. Right now i have 32's. Great for towing but screams on the highway so I'll run 35's. That should be a good mpg/towing mix. Somewhere in between at least.
Also there is a chance i will be picking up an EFI 300 and not a carbed 300. But either way, it's a 300. ALso I might be swapping a mazda

So a stock 300 will tow the load fine but just will take a bit to get up to speed right? some grades while gowing over the sierra won't be a big issue? There arn't any gnarly grades..

_________________
1969 f250 4x4 Restored, daily driver and heavy hauler.


Wed Oct 13, 2010 3:52 pm
Profile
VIP Member

Joined: Mon Jun 14, 2004 3:42 pm
Posts: 876
Location: Helena, MT. pop. enough
Post Re: Building 300 for towing
1971ford wrote:
Wow, lots of info, thanks guys...
When i said 18mpg's, i meant unloaded, i don't care about mpg's when loaded
The gears are 4.10's, but instead of swapping gears out I'll change tire sizes. Right now i have 32's. Great for towing but screams on the highway so I'll run 35's. That should be a good mpg/towing mix. Somewhere in between at least.
Also there is a chance i will be picking up an EFI 300 and not a carbed 300. But either way, it's a 300. ALso I might be swapping a mazda

So a stock 300 will tow the load fine but just will take a bit to get up to speed right? some grades while gowing over the sierra won't be a big issue? There arn't any gnarly grades..


For the kind of CGVW you are wanting to move around 4.10's and 32's are just fine. You dont want to go over 60mph anyway with that tail wagging the dog and you will want to have an equalizer hitch and the best brakes that $ can buy. The best trans for the setup you are contemplating would be a 4spd w/compound low ("granny gear") filled with synthetic gear oil. Then just dont be in a hurry and it will be fine, even in stock form. You will be able to climb the hills/grades at 35mph in 3rd gear and enjoy the scenery and not tear up the equipment. (the 300 is a tractor not a racer, if you want to go faster you will need a big block 8 or a diesel). On the flats you'll be able to hold 55-60 and get reasonably decent mileage (educated guess of 12-15 in stock form) while doing so.

The forgoing is based on my experiences pulling 5-6K trailers across country several times, including accross ethe Rockies, the Sierras and the Cascades with a stock 76 F150 4spd granny tranny 3.00 axle and 29" tires. ( I averaged 16 mpg by taking it easy and never going over 60. But all of the towing was done when it had between 20-60K miles on it) I still have the truck (now w/120K miles) its still in good shape and no rebuilds yet. Drove it to Oregon Coast and back this summer without a trailer and averaged 17mpg @70mph empty.

_________________
1 "76" F150 RC, LB, 2WD, 300, NP435, 9" open 3.00, special order 2-76/Delivered 4-76. Still "new".

1 "73-79" F150 RC/SS/SB/4WD, "84"-300, T18, NP205, 9" open 3.50, Dana 44 3.50 open, Offy DP, Holley 470, EFI + single 2.5" exhaust. Gathered from 15+ donor/parts trucks. "Fubar". Runs good, safe, still needs details/project continues.


Thu Oct 14, 2010 6:14 pm
Profile
Registered User

Joined: Tue Oct 05, 2010 2:05 am
Posts: 7
Post Re: Building 300 for towing
Sweet, exactly the info i was looking for.
You say about 35mph up grades with a stock 300... thats not too shabby i guess, but how would a slightly built 300 do? Say I swapped out the carb, intake, exhaust, ignition, and maybe the cam?
Would I be dreaming to be able to go 50 up grades after putting a $500+ into the 300?

_________________
1969 f250 4x4 Restored, daily driver and heavy hauler.


Thu Oct 14, 2010 10:42 pm
Profile
Registered User
User avatar

Joined: Sun Nov 22, 2009 5:32 pm
Posts: 420
Location: Twilight zone, WA
Post Re: Building 300 for towing
'71 -
I'd say go with your proposed upgrades (others here know way more about them than I do) and be happy with the results, whatever they may be.
Going 50 over grades with a heavy trailer? Depends on how steep, of course. Over Washington Pass in North Cascades (5,500 feet), especially from the West - no way. I-70 west of Denver (Floyd Hill, Georgtown grade, Eisenhower Tunnel, 8-10 K feet elevation), no way. Over Snoqualmie pass in WA on I-90 maybe. I like Luckyman's approach. Downshift and enjoy the view.

_________________
1995 F-150, 300-6, 4x4, ex-cab, sb, 3.08 5-speed, 2 1/2 in. exhaust w/flowmaster 50, MSD + ignition upgrades, canopy, 171,000 + miles Gone but not forgotten: 1965 F-100 240 3spd lwb "the green hornet"; 1991 f-150 300 5sp 2wd sb, 1960 F-250 4x4, 223 six, 4sp with wrap-around rear window, two-tone paint.
Tow vehicle: 2012 F-250 4x4 6.7 diesel XLT s/c lwb 20+mpg


Fri Oct 15, 2010 10:00 am
Profile
Registered User

Joined: Tue Oct 05, 2010 2:05 am
Posts: 7
Post Re: Building 300 for towing
Cool... time to drop a 300 in and post a build thread. 8)

_________________
1969 f250 4x4 Restored, daily driver and heavy hauler.


Fri Oct 15, 2010 12:46 pm
Profile
Registered User

Joined: Tue Oct 05, 2010 2:05 am
Posts: 7
Post Re: Building 300 for towing
What year and model truck do i find a mazda 5 spd behind a 300? And what year/models do i have a good chance in finding a 300?

I've been googling this trying to find out and have been looking uner all the hoods at the junkyard and can't find anything.

_________________
1969 f250 4x4 Restored, daily driver and heavy hauler.


Wed Oct 27, 2010 3:59 pm
Profile
VIP Member
User avatar

Joined: Fri Nov 08, 2002 6:54 pm
Posts: 8004
Location: Copley, OH
Post Re: Building 300 for towing
300s were introduced in the mid-60s and carried through until the 96 model year. They won't fit under the shorter hood design of the 97-up trucks. They should be very, very easy to find. Late model EFI trucks designate the engine as a 4.9 litre but it's the same engine.

The Mazda transmission was introduced with the 1988 model year behind the 300 and 302. Look for transmission code "M" on the vehicle ID sticker. Again should be very easy to find in any 88-96 truck with a 300 or 302 (5.0 litre.) The only question is WHY you would want one. It's a really poor excuse for a truck tranny.

_________________
1996 F-150 (tow missile)
1993 Mustang 5.0 (hot rod and auto-x monster)
1982 Tiga Formula Ford (SCCA racecar)
2013 Hyundai Elantra Coupe (daily driver)


Wed Oct 27, 2010 4:46 pm
Profile
Registered User

Joined: Tue Oct 05, 2010 2:05 am
Posts: 7
Post Re: Building 300 for towing
damn I say I am going to keep my np435 4spd since it's bullet proof and then people suggest swapping in a mazda 5spd instead. Then I say I'll put a 5spd in and they suggest a different tranny

Should I stick with my 4spd and just get a new bellhousing and drop a 300 in?

I couldn't find a single 300 at the junkyard nearby and it is a massive yard. a good half of the f150's had no motors in them so maybe 300's are in high demand right now haha

I'd like to get a couple more opinions on the EFI/carb subject. Carb would be sweet so i can fix it in the middle of no where desert (where all the races are) and would be simple but an EFI would probably get me another MPG or two, and i could get an extra of each sensor that may go out. Then I have to install a fuel pump too.

_________________
1969 f250 4x4 Restored, daily driver and heavy hauler.


Fri Oct 29, 2010 1:07 pm
Profile
VIP Member
User avatar

Joined: Fri Nov 08, 2002 6:54 pm
Posts: 8004
Location: Copley, OH
Post Re: Building 300 for towing
The Mazda tranny will drop your tow rating to something on the order of 2000-2500 lbs. add to that the not so minor fact that reverse gear is good for 30 MPH but so tall that it is useless for backing a trailer and you'll want to stick with the NP435. The Mazdog is just a terrible truck tranny. If you want a 5 speed, you'd need to look at the ZF which is a whole different animal.

What is your final drive ratio? If you posted it earlier, I missed it.

_________________
1996 F-150 (tow missile)
1993 Mustang 5.0 (hot rod and auto-x monster)
1982 Tiga Formula Ford (SCCA racecar)
2013 Hyundai Elantra Coupe (daily driver)


Fri Oct 29, 2010 1:36 pm
Profile
Registered User

Joined: Tue Dec 28, 2004 2:00 pm
Posts: 427
Location: Strasburg, VA
Post Re: Building 300 for towing
i've got an 87 short bed standard cab with the 300 and np435 4 speed.. 4x4. 3.08 gears. has towed everything i've asked it to. really a great combo. now if only the truck wasn't rusting out. :(

keep the 4 speed. you'll for sure regret the mazda trans. especially when the clutch slave cylinder goes out and you have to drop the tranny to replace it because it's inside the bellhousing.

_________________
87 F150 with a big six.

finally got the wheels on.. only after 5 years..


Sun Oct 31, 2010 12:04 pm
Profile
Registered User

Joined: Fri Jan 09, 2009 12:52 pm
Posts: 7
Post Re: Building 300 for towing
As far as using a mazda trans, all I can say is NO. Bad Idea. The trans you have could be the best light truck trans ever made, and since you seem to have a decent budget for this venture, why not troll ebay or clist for a gear vendors or similar auxiliary trans. I love the use of low range, unlocked hubs, in my 96, and would love to have a little taller gear for highway use. However if you want 18 mpgeeze... not happening with any motor that needs spark plugs, loaded anyway. I am trying to buy a 93 f250 IDI 7.3 from my former boss....it got 15-16 loaded similarly to you scenario with me driving (not my truck + not my fuel = less prudence with the thottle). You can drive daylight to dark, then let it keep you nice and toasty all night for days on end.

I love my 300, dont get me wrong, but towing that kind of weight for any distance on a consistent basis is going to be hard on it in any configuration. I think of mine like a 150 horse tractor. Sure, It'll pull whatever the heck I want it to, but I'm not heading for the opposite coast in the john deere there are better tools for that.

Edit:

x2 on the slave cylinder. First off, the engineer who designed it must have gotten a bonus check for extra stupidity. It's a pitiful design but an excellent business strategy to make the weakest link in the system the hardest to get to.

Keep the 4 speed.


Sun Nov 07, 2010 10:38 am
Profile
Global Moderator
User avatar

Joined: Sat Oct 18, 2003 10:49 pm
Posts: 5502
Location: The Great state of Ohio!!
Post Re: Building 300 for towing
oughtsix wrote:
As far as using a mazda trans, all I can say is NO. Bad Idea. The trans you have could be the best light truck trans ever made, and since you seem to have a decent budget for this venture, why not troll ebay or clist for a gear vendors or similar auxiliary trans. I love the use of low range, unlocked hubs, in my 96, and would love to have a little taller gear for highway use. However if you want 18 mpgeeze... not happening with any motor that needs spark plugs, loaded anyway. I am trying to buy a 93 f250 IDI 7.3 from my former boss....it got 15-16 loaded similarly to you scenario with me driving (not my truck + not my fuel = less prudence with the thottle). You can drive daylight to dark, then let it keep you nice and toasty all night for days on end.

I love my 300, dont get me wrong, but towing that kind of weight for any distance on a consistent basis is going to be hard on it in any configuration. I think of mine like a 150 horse tractor. Sure, It'll pull whatever the heck I want it to, but I'm not heading for the opposite coast in the john deere there are better tools for that.

Edit:

x2 on the slave cylinder. First off, the engineer who designed it must have gotten a bonus check for extra stupidity. It's a pitiful design but an excellent business strategy to make the weakest link in the system the hardest to get to.

Keep the 4 speed.


X2 on the last line.

_________________
OAPSE Union Member

Real men don't wear Bowties
When it come to engines If its .001 loose nobody knows, But if its .001 too tight EVERYBODY KNOWS!!
80 bronco FUV (farm utility vehicle)300 T-18 3.50s EFI head, offy C dual plenum, 500 edel carb, 1.7 roller rockers, Crane 260 cam EFI Exh


Sun Nov 07, 2010 12:02 pm
Profile
Registered User

Joined: Tue Oct 05, 2010 2:05 am
Posts: 7
Post Re: Building 300 for towing
okay, the 4spd stays, atleast until i can get a ZF.

I found a few 300's at the junkyard finally, too bad everyone leaves the hoods open in the rain.

_________________
1969 f250 4x4 Restored, daily driver and heavy hauler.


Wed Nov 10, 2010 3:07 pm
Profile
Registered User
User avatar

Joined: Tue Jan 06, 2004 12:16 pm
Posts: 298
Location: Sussex County, DE
Post Re: Building 300 for towing
1971ford wrote:
okay, the 4spd stays, atleast until i can get a ZF.

I found a few 300's at the junkyard finally, too bad everyone leaves the hoods open in the rain.


You made a wise choice to keep the 4 speed. If it's primarily a tow vehicle that won't be used at highway speeds without a trailer, I'd skip the ZF box, as the 4 speed is stronger than even the ZF box. As for people leaving hoods up in the yard, I totally understand. It's just plain inconsiderate. What yard owners/operators ought to do is remove the hood latches on vehicles so that the hoods can be raised/lowered easily, without concern that the hood will not re-open.

_________________
"The Argo" 321,000 miles and counting
It was a 1996 2wd Ford F-150 300ci Inline 6 NP-435 2.73:1 8.8" Rear;
It is a 1996 4wd Ford F-150 300ci Inline 6, C6 Transmission, 3.55:1 axles (limited slip in rear), BW 1356 manual shift transfer case with manual hubs
"Ah Ha Ha Ha Ha Ha! I Swear! Tractors is so dumb!" - Mater


Thu Nov 11, 2010 9:39 am
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 39 posts ] 


Who is online

Users browsing this forum: Bing [Bot], Yahoo [Bot] and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © phpBB Group.
Designed by Vjacheslav Trushkin for Free Forum/DivisionCore.