6 cyl mods?
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Joined: Jun 2003
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From: shepherd
overboring will give very little power gains. i am not sure about a stroker kit but i read an article on how to get 115 extra hp out of that brute 300. offenhouser 4bbl intake, cam in jegs, and some headers. get a small 4 bbl carb. the smallest you can get. it would make a good deal of extra power to 0 deck the block and port the head also.
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Joined: May 2002
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From: Broken Arrow, OK
Clifford used to offer a storker crank for the 300, I think it was 4.375" stroke. Even with that and a 0.060 over bore you are only at 340 cubic inches. My rule of thumb is that a 10% increase makes a stroker (or gears, or some other stuff) worth while, but in this case there are better ways to spend the money. A stroker will only make more power if it can get more air. Getting more air into a 300 is where the true challenge is.
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Joined: Apr 2003
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From: NB, Canada
So all the needed breathing mods are probably the best investment? What are the intake and exhaust manifolds worth, roughly? The two other 300's I've had were both standards. Is the c6 a good match for the 300?
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From: shepherd
yes it is a good heavy duty tranny but it eats up 60 extra hp than a c4 or c5. try ebay for good cheap deals on intakes. www.jegs.com has them to i believe
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From: shepherd
https://www.ford-trucks.com/framered...//www.jegs.com
remember i said i read something in a mag that increased up to 115hp? well it was this. how odd. but definately port your head to get more flow. 200 dollars for the intake. check it out
remember i said i read something in a mag that increased up to 115hp? well it was this. how odd. but definately port your head to get more flow. 200 dollars for the intake. check it out
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Joined: Nov 2003
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From: Kalispell, MT
i assume a machine shop would know what porting the head is... but for my own knowledge, if you don't mind....please explain...
MontanaFord
MontanaFord
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From: Coal Region
it means to enlarge the passages in the head slightly to allow for better flow and polish them is to make them smoother for the air to flow with less resistance. then theres gasket matching which is u take the intake/exhaust gaskets and draw an outline of it on the head and then port it until all the marks are gone.
id also like to add, get a 3 or 5 angle valve job done and up the compression to about 9.5:1 or so by decking the head.
id also like to add, get a 3 or 5 angle valve job done and up the compression to about 9.5:1 or so by decking the head.
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Mountain Pass
Joined: Dec 2003
Posts: 207
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From: Ontario, Canada
Would it be possible to somehow rig on a Mustang Throttle body and the injectors on my 300 straight 6? I have an 87 Mustang GT and I have a spare complete upper/lower intake and I was wondering what parts could be adopted to my 300 to perhaps make it work better. Also, on a different note, it was incredibly gutless when I got the truck (interhited, 88 F-250) and I found the second cat was plugged SOLID, so, after gutting it the truck works like a dream except for one tiny problem, when it gets warm and I idle for awhile it stumbles quite badly on initial acceleration for a few seconds and then it all of a sudden "takes off" is this possibly due to a bad TPS?
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Joined: May 2002
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From: Broken Arrow, OK
Don't mess with the TB, it isn't a direct bolt on and won't help anyway. There are a few people who have added 302, 351 and even 460 throttle bodies to their trucks and swear it made a huge difference, but none of them have produced dyno numbers yet. I know there is no vacuum behing the TB until after 4k rpm because I have measured it on a dyno; that tells me there is no restriction there. The 5.0 injectors go right into the 4.9 fuel rail and wiring, but are unnecessary on a stock engine. They also require an adjustable fuel pressure regulator for a 5.0 to be adapted to the 4.9. Lots of work for little if any gain.
The stumble could be any of 100 things. The first thing to do is change the fuel filter. If that doesn't help you might have a sticky fuel pressure regulator. There is really no way to know for sure without more information.
The stumble could be any of 100 things. The first thing to do is change the fuel filter. If that doesn't help you might have a sticky fuel pressure regulator. There is really no way to know for sure without more information.
Mountain Pass
Joined: Dec 2003
Posts: 207
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From: Ontario, Canada
Well, here is what happened prior to this issue: I had a very bad exhaust leak under the hood, enough that it would make you feel high when you were in the truck, you couldn't have the windows closed. So, I replaced the manifold gasket (exhaust and intake, one-piece felpro) and that got rid of the leak. Had no power, found out that it was my plugged-solid cat (inherited the truck), and that was probably the cause of the exhaust leak as well. Anyways, after replacing the gasket, it worked fine for about 3 days and then it started to stumble upon initial acceleration. I changed the fuel filter, no help. It works great once it "kicks in" but its that initial delay that is really annoying, yet, you can decelerate, and re-accelerate fine, its when you stop for say 30 seconds or longer that it does it. Would this throw a code and could a TPS cause this? About the Throttle Body swap, I've heard about the 460-swap, those are huge, but again, they are the dual-type, whereas the Mustang 302HO one is a single, is there a way to adapt it at all or should I just leave it alone until I magically manage to score one from a 460?
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Joined: Nov 2003
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From: Kalispell, MT
i've read about zero-decking the block...if i change to an offy intake, will i need to have the head ported? and will the intake come with neccessary gaskets? also...i'm planning to change to an EFI split (3 and 3) manifold, eventually...is 50 bucks a fair price from a junk yard? and would i hafta do any machining on the exhaust valves to match the holes there, as well? thanks...
MontanaFord
MontanaFord
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From: shepherd
you only bore if you need to if your cylinders ar scared up bad but if it does need to be bored you need to go the smallest possible so it won't overheat or crack. carb gaskets should come with the carb and the intake gaskets don't come with the intake.
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From: La Verne, California
Re: 6 cyl mods?
Yes there are!
Get your hands on "Petersen's Custom Classic Trucks" Magazine from August 2001 w/ a 50's lowered & chopped, Blown Yellow Chevy truck on the cover.
On the upper R/hand corner it states "More Power For Sixes".
Where on page 70 it showes a completely Tricked out 300 I-6.
Basic list in the article;
Headers
Four-Bbl manifold
270-degree duration cam
0.060 inch off the head for a 9-10:1 compression ratio
Port head
Install bigger valves, Better valve springs, Heavy duty keepers
Forged pistons
Aftermarket high-performance distributor & coil
Doug Fisher vibration damper
To avoid later problems do these first;
Magnaflux block & head for cracks first
Determin the deck is flat so NO blown head caskits
Make sure block not warped
Align-bore if necessary
Replace all bearings
New timing gears
Grind crank if necessary
Manifold mating surfices ground flat where it bolts on
Bolt together manifolds & grind them flat too
Balance & blue print whole engine, including flywheel & clutch.
One can get as much as 500hp out of a 300 I-6 if done properly.
Father did it for years for his friends who used to go out to the Olde Irwindale Raceway in So. Cal.
Merry Holidays
Get your hands on "Petersen's Custom Classic Trucks" Magazine from August 2001 w/ a 50's lowered & chopped, Blown Yellow Chevy truck on the cover.
On the upper R/hand corner it states "More Power For Sixes".
Where on page 70 it showes a completely Tricked out 300 I-6.
Basic list in the article;
Headers
Four-Bbl manifold
270-degree duration cam
0.060 inch off the head for a 9-10:1 compression ratio
Port head
Install bigger valves, Better valve springs, Heavy duty keepers
Forged pistons
Aftermarket high-performance distributor & coil
Doug Fisher vibration damper
To avoid later problems do these first;
Magnaflux block & head for cracks first
Determin the deck is flat so NO blown head caskits
Make sure block not warped
Align-bore if necessary
Replace all bearings
New timing gears
Grind crank if necessary
Manifold mating surfices ground flat where it bolts on
Bolt together manifolds & grind them flat too
Balance & blue print whole engine, including flywheel & clutch.
One can get as much as 500hp out of a 300 I-6 if done properly.
Father did it for years for his friends who used to go out to the Olde Irwindale Raceway in So. Cal.
Merry Holidays
Originally posted by 351 power
Are there kits/parts to stroke a 300? Overbore them?
Are there kits/parts to stroke a 300? Overbore them?
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