302 Intake Gasket

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SportsterSport
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302 Intake Gasket

Post by SportsterSport »

I have purchased a 91 302 for my f100 and switching to carb. I will be running edelbrock performer rpm and gt40p heads. I will do some very minor port work and a gasket match. I bought the intake used and it was gasket matched to a felpro 1262... Will this port be too big? It is a stock 302 with a cam and heads. Im kind of worried about losing velocity. I got a good deal on the intake so would I be OK with the 1262 or should I try to re-sell the intake and get one that has not been ported? Then I could go with the new style 1250...
RottenAppleRed
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Re: 302 Intake Gasket

Post by RottenAppleRed »

Gasket matching typically causes more air flow problems than it helps. 90% of gasket match port jobs result in "bell mouthing" the ports in the intake, as well as the ports in the heads. This causes turbulence and dead spots in the air flow. I buy the intake gaskets based on how good they seal...Fel-Pro Printaseal. My port work is only for function and most of the time a gasket matching won't line up on install. Now, if your intake is already cut and seams to be done well, the heads can be opened up...just do your best not to make too harsh of a transfer from opening to runner. The best way to tell is to dry fit everything and shine down the visible runners to check things out.

My biggest concern is the GT40P heads. Though they are excellent heads and flow really well as stock units, the valvesprings are pretty weak. These heads come off of Ford Explorers that have relatively small roller cams. The springs can only handle a stock Mustang 5.0HO camshaft...and it's close. Trick Flow has a great set of springs that are a suggested upgrade. Unless you have access to a knowledgeable PBM salesperson (great springs), then I'd stick with Trick Flow.
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Jacksdad
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Re: 302 Intake Gasket

Post by Jacksdad »

Alex's Parts sell a drop in spring kit for GT40P heads too. Like the TFS kit, they're right around $200.

If you're on a budget and not planning on either revving it above 6000 rpm or running a big cam (.500" and up), new stock replacements will work. Just be aware that they float at about 6200 rpm, but stock GT40P heads start to drop off after five grand anyway. I just picked up a set of stock springs from Rock Auto for less than $50.

Just make sure you toss the originals before they hurt your motor.
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Ranchero50
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Re: 302 Intake Gasket

Post by Ranchero50 »

I would not run 1262's with the black / gray felt construction. I could never get them to seal long term.
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SportsterSport
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Re: 302 Intake Gasket

Post by SportsterSport »

Thanks for the info! The intake looks to be done well so I will try the 1262S3 gasket it was matched with. I will have the machine shop check and refresh the p's also install springs to handle the Anderson N-41 cam. Thanks again!
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