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300 HP BB SIX

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GMUD2

300 HP BB SIX

Post #1 by GMUD2 » Mon Jun 06, 2005 7:06 pm

THANKS TO ALL THOSE WHO HELPED WHEN I NEEDED IT....
MY MOTOR IS FINALLY FINISHED AND TURNED OUT BETTER THAN I COULD HAVE EVER HOPED. TO ALL WHO WANT TO KNOW THE SET UP HERE GOES:
1-300 SIX BLOCK BORED .050 OVER
1-SET OF SIX 390 FORD PISTONS(FT W/ 2 VALVE RELIEFS)
1-COMP CAMS 66-248-6
1-SET COMP CAMS SPRINGS 6-903
1-SET CHEVY ROCKER ARMS FOR 250 SIX
1-SET CLIFFORD HEADERS 3X3
1-OFFENHAUSER SINGLE PLANE INTAKE
1-FLOW MASTER 2 INTO 1 COLLECTOR
1-SUMMIT CUTOUT
1-300 SIX HEAD MILLED .050 PORTED AND POLISHED, WITH SCREW IN VALVE STUDS.
MIX AS FOLLOWS---
SET PISTONS .030 DOWN THE BORE
ADD 1 HOLLEY 600 VACUUM SECONDARY
ADD 1 HEAVY RIGHT FOOT AND GO
THIS COMBINATION IS APPROXIMATLY 10.1:1 I PERSONALLY DO NOT RUN IT ON ANYTHING LESS THAN 92 OCTANE. IT REALLY LIKES 112 OCTANE BUT WHO CAN AFFORD TO RUN THAT ON THE STREET. IF YOU NEED MORE COMPRESSION ZERO DECK THE BLOCK AND RUN A MILLED 240 HEAD. THIS COMBINATION SHOULD BE ABLE TO MAKE AT LEAST 12 TO 13.5:1 WITH A MUCH LARGER CAM NEEDED. ONCE AGAIN MANY THANKS!!!!!!!!



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StrangeRanger
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Post #2 by StrangeRanger » Mon Jun 06, 2005 8:58 pm

Please tell me you replaced the phenolic timing gear with a metal one? Phenolic isn't going to like your valve springs.



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Post #3 by blue magoo » Mon Jun 06, 2005 11:25 pm

Hey that's awesome! I have some questions I've been planning a similar build. First what is the advertised lift and duration of that cam? I'm curious about how big a cam you can use and maintain enough valve clearence with this setup(the chevy rocker arms the head milling) Also, how much valve relief do you get from those pistons. And did you deck the block at all?



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Post #4 by Asa » Mon Jun 06, 2005 11:27 pm

the stock head will support over .600" of lift
so you should be able to figure out how close your valves will be as long as you know what's done to the engine and head


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Post #5 by blue magoo » Mon Jun 06, 2005 11:40 pm

Thanks, that pretty much clears up that issue for me.



GMUD2

Post #6 by GMUD2 » Tue Jun 07, 2005 5:33 pm

TO THE STRANGE RANGER THE TIMING GEAR IS NOW A STOCK STEEL AFTER MARKET SET



rancherlee

Post #7 by rancherlee » Wed Jun 08, 2005 8:33 am

I don't get the "SET PISTONS .030 DOWN THE BORE "

That right there KILLS Quench leaving ~0.70 squish which is fairly ineffective. When I went for more compression I took .019 off the BLOCK to bring the pistons to 0.000 in the hole and took only .010 off the head (9.0:1 compression roughly) but that left me in the Ideal 0.040 range (headgasket is ~0.040) for quench and it shows on my engine. I have NO issues with running cheap 87 octane on 9:1 compression with fairly agressive timing.



SYRacing

Post #8 by SYRacing » Wed Jun 08, 2005 10:45 am

why would you mill the head .050 and then set the pistons .030 down the bore?

wouldnt just milling the head .020 do the same exact thing?

impressive #s regardless..wish I was in the 300hp inline club :)
what did it make for torque?



Scott Freeman

300hp BB six

Post #9 by Scott Freeman » Wed Jun 08, 2005 10:53 am

I built one of those for my 69 4x4 pickup, the torque is awsome. and I get around 15 mpg. pulls 35's with 3.54 gears just fine.



GMUD2

rancherlee

Post #10 by GMUD2 » Wed Jun 08, 2005 5:55 pm

INHERENTLY THE 390 PISTONS ARE SHORTER THAN THE 300 SIX. AS FOR WHY I OPTED TO MILL THE HEAD THAT MUCH, IN THE FUTURE I PLAN ON GOING TO A 240 HEAD SET UP WITH LARGER VALVES. IF I HAD ZERO DECKED THE BLOCK AND THEN ADDED THE 240 HEAD COMPRESSION WOULD HAVE BEEN A LITTLE TOO HIGH(ABOUT 13:1 OR SO)



GMUD2

Post #11 by GMUD2 » Wed Jun 08, 2005 6:04 pm

SYRacing wrote:why would you mill the head .050 and then set the pistons .030 down the bore?

wouldnt just milling the head .020 do the same exact thing?

impressive #s regardless..wish I was in the 300hp inline club :)
what did it make for torque?


390 FLAT TOP PISTONS W/ 2VR HAD ABOUT 10 CC'S WORTH OF RELIEF TO THEM.THE STOCKERS HAD ABOUT 20 IF I AM REMEMBERING CORRECTLY. THATS WHY THEY ARE .030 DOWN THE BORE. REMEMBER THE HEAD IS CLOSED CHAMBER AND YOU WILL NOT GET AS MUCH REDUCTION IN CC'S AS YOU WILL MILLING THE BLOCK. AS TO THE TORQUE 375 @ 5500 RPM.



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Re: rancherlee

Post #12 by THE FRENCHTOWN FLYER » Wed Jun 08, 2005 7:05 pm

GMUD2 wrote: IF I HAD ZERO DECKED THE BLOCK AND THEN ADDED THE 240 HEAD COMPRESSION WOULD HAVE BEEN A LITTLE TOO HIGH(ABOUT 13:1 OR SO)




I just built an engine with 13:1 CR. It has totally flat pistons, no valve reliefs. To get 13:1 compression requires a head with 58 cc and only .010 deck (needed because I am using aluminum rods). The 240 head has 68 cc, so using it with a .030 deck and valve reliefs will result in something less than 13:1, I'm guessing around 11.5 / 12.


FORD 300 INLINE SIX - THE BEST KEPT SECRET IN DRAG RACING

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Post #13 by blue magoo » Thu Jun 09, 2005 7:02 pm

Does anyone know how much compression an engine with .060 milled off the head and .010 decked off the block would yield.



GMUD2

Post #14 by GMUD2 » Thu Jun 09, 2005 8:18 pm

blue magoo wrote:Does anyone know how much compression an engine with .060 milled off the head and .010 decked off the block would yield.

NOT ENOUGH INFO- 300 HEAD? STOCK PISTONS? HOW BIG IS THE DISH ON THE PISTONS? HOW MANY CC'S ARE LEFT IN THE HEAD.WITH THESE THE MATH IS EASY.



GMUD2

Re: rancherlee

Post #15 by GMUD2 » Thu Jun 09, 2005 8:25 pm

THE FRENCHTOWN FLYER wrote:
GMUD2 wrote: IF I HAD ZERO DECKED THE BLOCK AND THEN ADDED THE 240 HEAD COMPRESSION WOULD HAVE BEEN A LITTLE TOO HIGH(ABOUT 13:1 OR SO)




I just built an engine with 13:1 CR. It has totally flat pistons, no valve reliefs. To get 13:1 compression requires a head with 58 cc and only .010 deck (needed because I am using aluminum rods). The 240 head has 68 cc, so using it with a .030 deck and valve reliefs will result in something less than 13:1, I'm guessing around 11.5 / 12.


YOU ARE COMPLETELY CORRECT. WITH A 68 CC HEAD AND .030 DOWN THE BORE THE COMPRESSION IS AT 11.1:1. AT ZERO DECK THE COMPRESSION JUMPS TO 12.5:1. A ZERO DECK BLOCK WITH 58 CC HEAD IS AT 13.5:1.



fordman300

Post #16 by fordman300 » Thu Jun 09, 2005 8:45 pm

a 240 head with 68ccs, 10cc dish in the pistons, .040 thick head gasket with a bore of 4.060, and pistons .030 in the hole it only nets u with a static CR of 10.05 so your definatly running les than that now. if i were u i would have shaved the block to zero piston heigth and just cleaned up the head an puit bigger valves in it. your quenchj would have been far superior and netted u more power



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Post #17 by worken2much » Fri Jun 10, 2005 11:12 am

Many rebuilder pistons are by design a little shorter than the originals. The manufacturers are covering their arses a bit by doing this. The potential problem they are trying to avoid is this. If you put a new piston into an existing bore with a ridge present, (honed block but not rebored) you could get into a situation where the replacement pistion's top ring crashes into the slight ridge at the top of the bore. Especially if the replacement piston is even a few thousandth's taller from allowable manufacturer's tollerance. Thusly, by creating a slightly shorter piston this particular situation is avoided. In the typical grocery getter no one would ever notice nor care, only us performance people. This is the explanation offered to me by a engine builder who has been at it since BEFORE Shep was a pup. The bore in my particular engine was good enough that I was in this very situation.

It sounds to me like the the engine GMUD2 built has about the corect compression ratio for todays fuel and works well for him. Well done.

Humbly submitted/
worken2much



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Post #18 by blue magoo » Fri Jun 10, 2005 9:03 pm

How many cc's is a stock head?
Last edited by blue magoo on Fri Jun 10, 2005 9:13 pm, edited 1 time in total.



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Post #19 by blue magoo » Fri Jun 10, 2005 9:07 pm

[quote="GMUD2"][NOT ENOUGH INFO- 300 HEAD? STOCK PISTONS? HOW BIG IS THE DISH ON THE PISTONS? HOW MANY CC'S ARE LEFT IN THE HEAD.WITH THESE THE MATH IS EASY.[/quote]

OK, Stock carbed 300 head with .060 milled off, for know stock pistons, deck .010 off the head. The reason i'm asking is because this is what Clifford recomends for a street strip engine. Also,I dont think stock pistons would hold up well, but this would give me a ballpark number



Guest

Post #20 by Guest » Fri Jun 10, 2005 9:22 pm

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Last edited by Guest on Sat Sep 03, 2005 3:52 pm, edited 1 time in total.



alaskatruck

Torque

Post #21 by alaskatruck » Mon Jun 13, 2005 4:42 am

I am new to the I6 world and recently purchased a 86 f-150 with a 300. The engine is old and tired with blow by through the valves. I am planning on doing a through rebuild and would like to get 300 ftlb out of it. I like the idea of going .020 over with a zero deck height and shaving .010 off the head. I see that some one did this and want to know this worked out. I do plan on replacing the intake with a offenhauser and a EFI exhaust manifold. I live in an area of Alaska where smog is not an issue. :?



GMUD2

Post #22 by GMUD2 » Wed Jun 15, 2005 4:41 pm

357f-150 wrote:What kinda intake vacuum you getting with that 268H cam, GMUD2?

Sounds like a nice build.


WITH A HOLLEY 600 VAC SEC 15 INCHES WITH A 750 VAC SEC 8 INCHES
THE 750 IS WAY TOO MUCH CARB THOUGH. I AM THINKING A 650 MECHANICAL MIGHT BE THE TICKET.



Guest

Post #23 by Guest » Fri Jun 17, 2005 11:37 am

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Last edited by Guest on Sat Sep 03, 2005 3:52 pm, edited 1 time in total.



maynard

Post #24 by maynard » Fri Jun 17, 2005 2:36 pm

357f-150 wrote:Is a video or soundclip possible?



Sound clip is from my 300 using the 268H.

Exhaust consists of true 2" dual Dynomax headers, home made 'X' pipe, no cats, no muffler and exits out of 3" tips at a 45 deg. angle behind the truck.

http://home.woh.rr.com/picturesandstuff/RobTruckSound.wav



Guest

Post #25 by Guest » Fri Jun 17, 2005 3:53 pm

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Last edited by Guest on Sat Sep 03, 2005 3:52 pm, edited 1 time in total.



maynard

Post #26 by maynard » Fri Jun 17, 2005 10:15 pm

357f-150 wrote:What rpm was your idle set at in the soundclip maynard? Appreciate the soundclip.


800 RPM



Guest

Post #27 by Guest » Sat Jun 18, 2005 8:44 am

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Last edited by Guest on Sat Sep 03, 2005 3:53 pm, edited 1 time in total.



maynard

Post #28 by maynard » Sat Jun 18, 2005 2:16 pm

357f-150 wrote:Maynard

Really, I was expecting you to post less. Has a nice sound to it.

Nice avatar picture!!



Thanks very much.
:D



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nice pic....

Post #29 by mutt » Sun Jun 19, 2005 7:40 pm

you got other pics of yr engine? Id like to try to print some out to add to the shop wallpaper, and as inspiration...mutt



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Post #30 by j41385 » Thu Jun 23, 2005 5:47 am

I have a question for you guys...
I just rebuilt a 300. It has an offy C, Edelbrock 500CFM, Comp 268 Cam, Metal timing Gear, Hedman Header, 30 over Ross Forged pistons and some machine work that give 9.5:1CR, MSD 6a and Blaster II, 9MM plug wires.


Here's What I need to know...

Will stock lifters and valve springs work with that Cam?
I haven't started it yet, figured I should know before I do...

Thank You.


1968 F100 Built 300 Inline 6.


6 in a row makes it go...if it's a V it ain't for me.
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Grandma Likes V8's.

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Post #31 by StrangeRanger » Thu Jun 23, 2005 7:54 am

Lifters, yes.
Springs, maybe. Or at least maybe not for long.



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Post #32 by Lazy JW » Thu Jun 23, 2005 9:17 pm

Or do like I do and don't rev past 3500 rpm. Ever.
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

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Post #33 by j41385 » Thu Jun 23, 2005 9:29 pm

I don't think that will be very easy, considering my 72 has no tach. And I am out to Kill "the worlds greatest engine" the 350. My chevy buddy laughs at me because I took a good running 360 8 popper out to put my 300 in.


1968 F100 Built 300 Inline 6.





6 in a row makes it go...if it's a V it ain't for me.

Image

Grandma Likes V8's.

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Post #34 by Lazy JW » Thu Jun 23, 2005 9:39 pm

I took out an oil-slobberin' 360 (is there any other kind?) to put in a 300 but it was mostly motivated by lack of funds (like most everything I do). If you are out to conquer the infamous Chebbie it would be a good plan to NOT cheap out on the valve springs. A cam is no better than the valve springs that you use because if they lose control of the valve train you can just wave goodbye to the Chebbie driver's tail lights (he bought good valve springs).
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

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Post #35 by j41385 » Thu Jun 23, 2005 9:45 pm

ok I am getting those for sure then, but is what strange ranger said correct that my New stock lifters will work fine? I like to get second opinions. No offense intended.

Thanks


1968 F100 Built 300 Inline 6.





6 in a row makes it go...if it's a V it ain't for me.

Image

Grandma Likes V8's.

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Post #36 by Lazy JW » Thu Jun 23, 2005 9:59 pm

Stock lifters should be just fine.
Joe

Edit: Best look at some heavier pushrods too, those stockers will flex too much at high loads. 3/8" diameter should help.


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

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Post #37 by THE FRENCHTOWN FLYER » Mon Jun 27, 2005 3:06 pm

If you are going to run the stock lifters set them at only 1/4 - 1/2 turn down from "no lash".


FORD 300 INLINE SIX - THE BEST KEPT SECRET IN DRAG RACING

Scott Freeman

lots o torque

Post #38 by Scott Freeman » Fri Jul 08, 2005 3:59 pm

Hey I built one of those for my 69 shortbox with 3/4 ton running gear. I have managed to break the rear dana60 twice. the first time I managed to break the cross shaft in the differential. recently I broke the welds loose in the housing that holds the tube in it. had to take the ladder bar off to remedy it. guess 35's are too big to try to do burn outs



Gerry Lutz Jr.

Post #39 by Gerry Lutz Jr. » Fri Jul 08, 2005 6:27 pm

I snapped a ford 8.8 the same way lol. The motor itself can turn them the drivetrain can't take the abuse though.



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