Cam or higher ratio rockers?
- Thread starter StarDiero75
- Start date
I thought I said what my intentions are with the car. But I'll repost them since they're hiding in a paragraphdrag-200stang":2h1kmhgu said:
This is a street driven, daily car that I'm looking to get the most power from, but keep or increase mileage as much as possible and have a good idle. I will sacrifice a little mileage though for power hehe.
"...Would advancing that cam a little help give more torque down there? Or should it be fine as is?..."
not sure - but would the on-line gear / RPM calculaters help U decide?
(tire dia, rear gear, tranny, rpm)
not sure - but would the on-line gear / RPM calculaters help U decide?
(tire dia, rear gear, tranny, rpm)
I was not clear. What I meant was, the parts that you plan to order before you order.StarDiero75":2tzvzcsa said:
Kind of like the guy that just bought a rebuilt 66 head and asks how he can get more power out of his engine.
sorry to interject - but seems like gettin into my fav subject on frd6:
"the auto is a system"
power v MPGs
or my wrd for: performance.
Can't we have both...
Here our bra is mid way in the plannin (head gettin near optimal, stuff yet ta do...
"the auto is a system"
power v MPGs
or my wrd for: performance.
Can't we have both...
Here our bra is mid way in the plannin (head gettin near optimal, stuff yet ta do...
:mrgreen:
top left corner
https://www.google.com/search?client=sa ... 82&bih=708
thats some good info X.
Wondering abt comparison to Ryan's rig w/RPM'n MPH his tire sz, etc...
Guys told me I couldn't run an i6 in my bronk w/411 rear, 33X15 inch tires. A gear caculator & above
gave a different answ.
https://www.google.com/search?client=sa ... 82&bih=708
thats some good info X.
Wondering abt comparison to Ryan's rig w/RPM'n MPH his tire sz, etc...
Guys told me I couldn't run an i6 in my bronk w/411 rear, 33X15 inch tires. A gear caculator & above
gave a different answ.
Using the calculator is what made me think about advancing the cam. At 60 I'm turning 1829 rpms. I need my torque low to hold that.chad":5h3wphjx said:
My specs are:
2.8 or 2.79 rear (i heard 2.8 is rare so maybe 2.79)
25" tires
.81 5th
1822 with a 2.79 or 1829 with 2 8
Or if i need to, i can go down to a 24" tire and that ups it to 1898 with 2.79 or 1905 with 2.8
So if I'm getting what you're saying, likedrag-200stang":26j2vrqy said:
256H Schneider cam
Dual roller timing chain
Cam bearings (if you all think i should do it)
Break in lube and oil
New springs and retainers from Schneider (probably 302 or whatever they have that'll match well)
Victor or Fel pro head gasket (I'll find out when i CC the chambers on my 2V head)
ARP head studs
1.50 exhaust valves
This is all for the head swap and cam install.
Towing a maximum legal load boat up an 8% incline at a boat ramp with a unibody sets the 1st gear ratio and axle ratio. Torque to weight sets the scale factors on those.
Ford had an internal memorandom on these in Australia. A 316 ft lb 351 4bbl could cope with a 2.46 1st, a 2.75 axle and 3850 pounds of car. A 160 ft lb 200 1bbl could cope with a 2.95 1 st, a 2.92 axle and a 3150 pound car.
My 2450 pound Cortinas 200 had optional 2.53 or 2.77 axle gears even with a manual gearbox with 2.95 first. As weight and heft is removed, even little 200's can cope with the same moonshot gearing the 1980 to 1981 255 Foxes and Panther based cars got.
With a 2.46 Ist, a just an old formerly 120 hp 255 can run 3.45 gears, a 0.67 overdriven top, and do the same 1898 rpm at 60 mph, then 132 mph at 4100rpm with the 1980 G vin 351 HO 165 hp 260 in /274 ex cam in an automatic 1981 Mercury Capri weighing 2800 ponds. That hoary old Marine 351 cam was also used in the 300 hp 1994 SVT 351Mustang.
Ford aced the class at gearing with the reduced weight Foxes from 1978 to 1993. Overal top gears of 2.05 were had on the automatic overdrive 5.0 and 4.2 Thunderbirds, the smaller 4.2 Foxes got 2.29 axles, the 2.3 Foxes got 4.03 and 3.97 firsts to cope with trailer park and traffic jamb duties.
The last 2650 pound 1981 3.3 Foxes got 2.47 axles and optional T4 versions of the T5 with 4.03 firsts gears and at 60 mph, they did 2023 rpms with 14 inch or 390 mm TRX wheels. Or the same geared 1980 or 1981 model year SROD option with 3.08 gears, and every ratio re-adjusted to give a 2.49 ratio effective top with the same 0.81 top gear found in some truck SROD's.
The overdrive Tremec 140 5 speed of 1980 had the same gears as the later 4 cylinder T5 you plan on using Ryan.
On a light car, but now with really good power and torque to weight figures, your copying what Ford did with the 1980-81 "Second Gas Crunch" 3.3 Foxes.
You can go up in exhaust duration and not hurt fuel economy. Ford did just this with the 73 Torino cam in the 82-84-1/2 Mustang 5.0's, and the marine cam the G vin 1980 5.8 2bbls used.
With so little mass, you could even use Crosley's 274 solid Clay Smith cam, and still be able to cruise and stay in high gears in yield snd take roads. Anything less than 274 or 278 is a waste on log heads with direct mounts. Gas mileage hike happens when you fail to add compression, fail to take extra base advance, fail to drop back the total advance. 34 is often too much.
The bigger 2150 carbs can be used if the base idle air and transfer slot needle profiles are tuned right.
Economy is two edged. The Falcon based Chero is lighter, and if the tray deck is covered, even the blunter 64s snd 65s are slick bricks.
The 5.0 4bbl and HO 2v Fox's with the stick shifts were the ultimate economy cars. Geting high 25s, and still being able to shut down fat 305 msnuals and 350 autos is what the 5.0s did. 3.3 without the Falcon Six perfirmsnce mods are thirsty and slow....
Ford had an internal memorandom on these in Australia. A 316 ft lb 351 4bbl could cope with a 2.46 1st, a 2.75 axle and 3850 pounds of car. A 160 ft lb 200 1bbl could cope with a 2.95 1 st, a 2.92 axle and a 3150 pound car.
My 2450 pound Cortinas 200 had optional 2.53 or 2.77 axle gears even with a manual gearbox with 2.95 first. As weight and heft is removed, even little 200's can cope with the same moonshot gearing the 1980 to 1981 255 Foxes and Panther based cars got.
With a 2.46 Ist, a just an old formerly 120 hp 255 can run 3.45 gears, a 0.67 overdriven top, and do the same 1898 rpm at 60 mph, then 132 mph at 4100rpm with the 1980 G vin 351 HO 165 hp 260 in /274 ex cam in an automatic 1981 Mercury Capri weighing 2800 ponds. That hoary old Marine 351 cam was also used in the 300 hp 1994 SVT 351Mustang.
Ford aced the class at gearing with the reduced weight Foxes from 1978 to 1993. Overal top gears of 2.05 were had on the automatic overdrive 5.0 and 4.2 Thunderbirds, the smaller 4.2 Foxes got 2.29 axles, the 2.3 Foxes got 4.03 and 3.97 firsts to cope with trailer park and traffic jamb duties.
The last 2650 pound 1981 3.3 Foxes got 2.47 axles and optional T4 versions of the T5 with 4.03 firsts gears and at 60 mph, they did 2023 rpms with 14 inch or 390 mm TRX wheels. Or the same geared 1980 or 1981 model year SROD option with 3.08 gears, and every ratio re-adjusted to give a 2.49 ratio effective top with the same 0.81 top gear found in some truck SROD's.
The overdrive Tremec 140 5 speed of 1980 had the same gears as the later 4 cylinder T5 you plan on using Ryan.
On a light car, but now with really good power and torque to weight figures, your copying what Ford did with the 1980-81 "Second Gas Crunch" 3.3 Foxes.
You can go up in exhaust duration and not hurt fuel economy. Ford did just this with the 73 Torino cam in the 82-84-1/2 Mustang 5.0's, and the marine cam the G vin 1980 5.8 2bbls used.
With so little mass, you could even use Crosley's 274 solid Clay Smith cam, and still be able to cruise and stay in high gears in yield snd take roads. Anything less than 274 or 278 is a waste on log heads with direct mounts. Gas mileage hike happens when you fail to add compression, fail to take extra base advance, fail to drop back the total advance. 34 is often too much.
The bigger 2150 carbs can be used if the base idle air and transfer slot needle profiles are tuned right.
Economy is two edged. The Falcon based Chero is lighter, and if the tray deck is covered, even the blunter 64s snd 65s are slick bricks.
The 5.0 4bbl and HO 2v Fox's with the stick shifts were the ultimate economy cars. Geting high 25s, and still being able to shut down fat 305 msnuals and 350 autos is what the 5.0s did. 3.3 without the Falcon Six perfirmsnce mods are thirsty and slow....
"I cant think of better cam, carb and gearing choices."
"Anything less than 274 or 278 (cam) is a waste on log heads with direct mounts. Gas mileage hike happens when you fail to add compression, fail to take extra base advance, fail to drop back the total advance. 34 is often too much."
Forgodabout how light the lill chero is. Just thinkin "ol cars" (not unibody, heavy frame, "open tray", solid sheet metal).
"Anything less than 274 or 278 (cam) is a waste on log heads with direct mounts. Gas mileage hike happens when you fail to add compression, fail to take extra base advance, fail to drop back the total advance. 34 is often too much."
Forgodabout how light the lill chero is. Just thinkin "ol cars" (not unibody, heavy frame, "open tray", solid sheet metal).
Three pieces of advice before the ink dries on your cheque.
1. If you cannot run 14*-16* base advance on 87 octane without pinging at 1500 to 4500 rpm, then you need to peg back the peak advance, and if
you are running premium fuel on a stock 3.3 or any other 4.1 or 4.9 Ford, then your pi%%ing your money away.
2. Anti Detonation Injection . Mike1157's Gila Monster is a turbocharged X flow. He miscalculated his chamber volume, and is now living with a 10.7:1 CR.
https://www.stangnet.com/mustang-forums ... st-9174171
It runs great with a 10 degree base advance, and unboosted, its about 32 degrees. Each pound of boost, it gets retarded back a degree, and it "tips-in" to 22 at 10 pounds of boost. Most likely 450 know free horsepower.
3. EGR should be kept with either a 135 or 175 rating valve, and it'll allow you to run really high peak advances if thats what you need.
In my opinion, 36-38 peak is dangerous unless you've got knock detection and the pink wire hooked to the Duraspark or EST unit for a DU1.
For most modified Ford sixes with better intake, carband a common 8.8:1 to 9.3:1 compression bump up from the stock 8.0-8.4:1, 32- 34 is safer.
In my opinion, Ford did ignition advance tuning better than anyone else, but it did some strange stuff you all have to be mindfull of if you want to run 9.3:1 on a 256 degree, 200 50 thou duration cam.
Okay, the examples you need to know before getting into it.
Eg 1. Having too much. The emissions legal California 97 to 100 octane 10.7:1 Boss 302 and 351 4V HO Cleveland engines for late 1969 had 16 degrees of base advance, and could carry 34 total. Those engines were 275 to 300 hp net with an Air Pump Thermactor. The Distrovac system (which was used in the stick shift Maverick till 1973) used a Spark Vacuum signal to control warm up advance, and it was speed related, and worked great.
Downgrading to 91 to 93 octane, it would still run without detonation, but no dice if it was long shelf gas, as a 93 octane isn't still 93 octane after 5 weeks. The problem was the stock 351 4bbls had a 256 cam, while the hotter versions had a raft of other higher duration cam specs which blead off combustion pressure, so some Boss 351's could cope with lower octane , even 91 okay if the peak advance was reduced.
Eg 2. Having too little. The Fly in a Frost compression ratio drop for 1972 ment Ford could go straight away with a stock 10 degree base timing and 38 peak advance on any sub 8:1 compression engine, even the Pantera L's and Mustang 351 HO's for 1973 were still making excellent power and reasonable fuel figures with agressive 270/280 spilt cams. Duraspark I was used in these engines, and it allowed the huge 38% drop in compression not to result in a massive loss on horspower. The loss was from 330 hp net to 266 hp net on the HO version of the Mustang 351, and either 248 or 266 hp on the 1974 non California spec 351 Pantera. That's a 16% power loss, mainly for emissions.
Eg. 3 Temperatures. I'm lucky, down here it gets down to 14 degrees F in neighboring Ranferly, and to 1.4 degrees F in my old home town. In the 265 to 375 hp net area, all my 350 and 351 builds, you should just compare the warm up of an emission controlled heat stoved 750 cfm spread bore 351C March I with Distrovac verses a non emissions 375 hp 351C with 780 Holley. American emissions carb controls are just great for warm up, less so under wide open throttle.
Eg . 4 Ford going back up from 7.9-8.4:1 engines to more. Knock sensor 1980 351 G code HO LTD's and Marquis's had high advances, and then had them pegged back 10 degress if know was detected.
So Ford was way ahead on matching higher duration performance cams with Duraspark systems.
I had a succession ofDuraspark I6 Fords. My 81 Stang was the all time best warming up car I ever had.
an 81 US smog 3.3 to an 1980-81 non automatic choke 1v 126 hp 4.1 Falcon, the mildly emission Aussie spec Falcon wasn't nearly as good.
The next year, with an automatic choke 1982 2v 4.1 Falcon with 141 hp.
Now those later cars were 13 to 15% more economical with quicker cold start light off just via some really basic thermatic valves. The 82-84's were downright fun to warm up even in the snow at 32 deg F in Dunedin where I live.
Regular gas era cars were much better for cold start emmisions and even the 1986 EFi 5.0 Mustang ran 9.2:1 compression, could take a base advance of 10 tO 14 degrees with. It went up to 9.5 for 1993-1995. Same applies.
My 1984 9.7:1 propane alloy head X flow 250 ran 32 degrees total with 9 degrees static.
Stock US emissions era 9-91 octane 250's were 8.0:1 actual compression, the 200, 8.4:1.
The Australian alloy head conversion was done late 1980, and 200 to 250 engines on 89-91 octane were pegged back from 9.35:1 in the 97 octane engines to just 8.7:1 for the regualr gas engines.
The basic advance ramp from idle to full advance was steeper in the regular gas engines, but got pegged back to about 34 degrees from 38. From 1986 to 1993, the realted to 4.1 alloy head cross flow becamew the 4.0 liter OHC. Its compression ratio was bumped right back up to 9.7:1, and the peak advance was kept back at 35.5 degrees, just like the Ford Explorer SOHC 4.0, beacuise they used a really awesome igntion system, allot heads and
Like I say, My 81 3.3 Mustang was stock at 10 degrees, and then looped out to 38 total when cold.
I like to avoid excessive emissions, so I like spark sustain, Cold start Parts Per million emission reduction helps cold start warm up.
The trick to making a high compression, low bleed off, high DCR engine run well is to ask Bill to peg back the peak advance, and don't be affraid to use the 7508-1, 7508-2, 1-684, 1-592 or 9117 Holley 2-bbl 289-302-390 1.19" replacement carb style of Reverse Idle base advance. Those carbs were designed around a Bowl Vent, and work best if the the old Carter 4-BBL Thermoquad system is used.
Eg 5, and my best advice, as EGR and spark advance work both ways to allow detonation to be controlled; you'll get another 4 degrees advance noramlly with EGR present.
I like Fords Australian 79-85 5.8 liter 4bbl system; they did it the other way around to the Equally excellent 5.0/5.8/429/460 4 barrel used in the F Trucks and Mustangs
....a retard lock-out, with ported to manifold switch-over.
35°C = 95°F
55°C = 131°F
107°C = 224.6°F
Best part is that the found Item 3, Green DVCV2 port PVS vaccum switches
And Item 2, Blue TCVV 3 port vaccum switches
and Item 5 (no letter suffix) the Black SDV Spark Delay or Vaccuum delay valve are so easy to get, it makes a hand free Idle warm up while getting Coffee at Toms Diner a way to warm your car up while listing to one Suzanne Vega song..
The Aussie situation was extreme right about 82-83. Even the 188 4.9 and 200 hp 5.8 had even worse than US 5.0 Mustang and 5.8/429/460 Carb truck underhood heat issues, because US V8's always had good radiator servicing air, while the 1982 Australian V8's and I6's had no real hood opening at the radiator, Ford was progressing to other methods of detonation control. The air cleaner had gotten a special adaptor to get cool air in.
The 4180C/4185EG/4190EG system
http://vb.foureyedpride.com/showthread. ... ance/page2
1. If you cannot run 14*-16* base advance on 87 octane without pinging at 1500 to 4500 rpm, then you need to peg back the peak advance, and if
you are running premium fuel on a stock 3.3 or any other 4.1 or 4.9 Ford, then your pi%%ing your money away.
2. Anti Detonation Injection . Mike1157's Gila Monster is a turbocharged X flow. He miscalculated his chamber volume, and is now living with a 10.7:1 CR.
Mike1157":3sqwmt95 said:
https://www.stangnet.com/mustang-forums ... st-9174171
It runs great with a 10 degree base advance, and unboosted, its about 32 degrees. Each pound of boost, it gets retarded back a degree, and it "tips-in" to 22 at 10 pounds of boost. Most likely 450 know free horsepower.
3. EGR should be kept with either a 135 or 175 rating valve, and it'll allow you to run really high peak advances if thats what you need.
In my opinion, 36-38 peak is dangerous unless you've got knock detection and the pink wire hooked to the Duraspark or EST unit for a DU1.
For most modified Ford sixes with better intake, carband a common 8.8:1 to 9.3:1 compression bump up from the stock 8.0-8.4:1, 32- 34 is safer.
In my opinion, Ford did ignition advance tuning better than anyone else, but it did some strange stuff you all have to be mindfull of if you want to run 9.3:1 on a 256 degree, 200 50 thou duration cam.
Okay, the examples you need to know before getting into it.
Eg 1. Having too much. The emissions legal California 97 to 100 octane 10.7:1 Boss 302 and 351 4V HO Cleveland engines for late 1969 had 16 degrees of base advance, and could carry 34 total. Those engines were 275 to 300 hp net with an Air Pump Thermactor. The Distrovac system (which was used in the stick shift Maverick till 1973) used a Spark Vacuum signal to control warm up advance, and it was speed related, and worked great.
Downgrading to 91 to 93 octane, it would still run without detonation, but no dice if it was long shelf gas, as a 93 octane isn't still 93 octane after 5 weeks. The problem was the stock 351 4bbls had a 256 cam, while the hotter versions had a raft of other higher duration cam specs which blead off combustion pressure, so some Boss 351's could cope with lower octane , even 91 okay if the peak advance was reduced.
Eg 2. Having too little. The Fly in a Frost compression ratio drop for 1972 ment Ford could go straight away with a stock 10 degree base timing and 38 peak advance on any sub 8:1 compression engine, even the Pantera L's and Mustang 351 HO's for 1973 were still making excellent power and reasonable fuel figures with agressive 270/280 spilt cams. Duraspark I was used in these engines, and it allowed the huge 38% drop in compression not to result in a massive loss on horspower. The loss was from 330 hp net to 266 hp net on the HO version of the Mustang 351, and either 248 or 266 hp on the 1974 non California spec 351 Pantera. That's a 16% power loss, mainly for emissions.
Eg. 3 Temperatures. I'm lucky, down here it gets down to 14 degrees F in neighboring Ranferly, and to 1.4 degrees F in my old home town. In the 265 to 375 hp net area, all my 350 and 351 builds, you should just compare the warm up of an emission controlled heat stoved 750 cfm spread bore 351C March I with Distrovac verses a non emissions 375 hp 351C with 780 Holley. American emissions carb controls are just great for warm up, less so under wide open throttle.
Eg . 4 Ford going back up from 7.9-8.4:1 engines to more. Knock sensor 1980 351 G code HO LTD's and Marquis's had high advances, and then had them pegged back 10 degress if know was detected.
So Ford was way ahead on matching higher duration performance cams with Duraspark systems.
I had a succession ofDuraspark I6 Fords. My 81 Stang was the all time best warming up car I ever had.
an 81 US smog 3.3 to an 1980-81 non automatic choke 1v 126 hp 4.1 Falcon, the mildly emission Aussie spec Falcon wasn't nearly as good.
The next year, with an automatic choke 1982 2v 4.1 Falcon with 141 hp.
Now those later cars were 13 to 15% more economical with quicker cold start light off just via some really basic thermatic valves. The 82-84's were downright fun to warm up even in the snow at 32 deg F in Dunedin where I live.
Regular gas era cars were much better for cold start emmisions and even the 1986 EFi 5.0 Mustang ran 9.2:1 compression, could take a base advance of 10 tO 14 degrees with. It went up to 9.5 for 1993-1995. Same applies.
My 1984 9.7:1 propane alloy head X flow 250 ran 32 degrees total with 9 degrees static.
Stock US emissions era 9-91 octane 250's were 8.0:1 actual compression, the 200, 8.4:1.
The Australian alloy head conversion was done late 1980, and 200 to 250 engines on 89-91 octane were pegged back from 9.35:1 in the 97 octane engines to just 8.7:1 for the regualr gas engines.
The basic advance ramp from idle to full advance was steeper in the regular gas engines, but got pegged back to about 34 degrees from 38. From 1986 to 1993, the realted to 4.1 alloy head cross flow becamew the 4.0 liter OHC. Its compression ratio was bumped right back up to 9.7:1, and the peak advance was kept back at 35.5 degrees, just like the Ford Explorer SOHC 4.0, beacuise they used a really awesome igntion system, allot heads and
Like I say, My 81 3.3 Mustang was stock at 10 degrees, and then looped out to 38 total when cold.
I like to avoid excessive emissions, so I like spark sustain, Cold start Parts Per million emission reduction helps cold start warm up.
The trick to making a high compression, low bleed off, high DCR engine run well is to ask Bill to peg back the peak advance, and don't be affraid to use the 7508-1, 7508-2, 1-684, 1-592 or 9117 Holley 2-bbl 289-302-390 1.19" replacement carb style of Reverse Idle base advance. Those carbs were designed around a Bowl Vent, and work best if the the old Carter 4-BBL Thermoquad system is used.
Eg 5, and my best advice, as EGR and spark advance work both ways to allow detonation to be controlled; you'll get another 4 degrees advance noramlly with EGR present.
I like Fords Australian 79-85 5.8 liter 4bbl system; they did it the other way around to the Equally excellent 5.0/5.8/429/460 4 barrel used in the F Trucks and Mustangs
....a retard lock-out, with ported to manifold switch-over.
35°C = 95°F
55°C = 131°F
107°C = 224.6°F
Best part is that the found Item 3, Green DVCV2 port PVS vaccum switches
And Item 2, Blue TCVV 3 port vaccum switches
and Item 5 (no letter suffix) the Black SDV Spark Delay or Vaccuum delay valve are so easy to get, it makes a hand free Idle warm up while getting Coffee at Toms Diner a way to warm your car up while listing to one Suzanne Vega song..
The Aussie situation was extreme right about 82-83. Even the 188 4.9 and 200 hp 5.8 had even worse than US 5.0 Mustang and 5.8/429/460 Carb truck underhood heat issues, because US V8's always had good radiator servicing air, while the 1982 Australian V8's and I6's had no real hood opening at the radiator, Ford was progressing to other methods of detonation control. The air cleaner had gotten a special adaptor to get cool air in.
The 4180C/4185EG/4190EG system
http://vb.foureyedpride.com/showthread. ... ance/page2