351w swap 94 gt

[98blackstallion]

so do you really have to upgrade to headers when you put a 351 into say a 95 gt? why won't the stock manifolds work?

 

[99FiveOh]

The engine is wider, therefore it puts the heads out wider and taller than a 302. So if you want your existing H pipe to match up, you have to get headers for a 351.

 

[98blackstallion]

Thanks man! I just bough the car and they have some gay custom crap on it. It doesn't have a mid pipe per say anymore just piping.

 

[BlackVert]

well, you can try putting the old headers on there, and if they don't hit anything, and you don't mind getting some pipes bent to get it all hooked up, then maybe you can get by without swap headers

 

[99FiveOh]

I think people have tried before and what happens is your flange interferes with the firewall because they don't hang low and hug into the block enough. Remember, it's pretty tight in there even with the factory stuff!

 

[98blackstallion]

what can I do about the fuel rails? Any junk yard units that can be used?

 

[98blackstallion]

also what is the balance on the 351w? 50 or 28oz?

 

[99FiveOh]

Balance is 28 oz. Fuel rails can be sourced from an EFI 351 or you can modify the stock 302 one by cutting it and extending it with a hose. The pressure in the fuel rail isn't that much, so a clamped on crossover hose would be fine.

 

[98blackstallion]

ok got a distributor from a 95 bronco with a 351w so I'm good there even with the cam gear right since a roller dizzy?


Also finally question,

What is the balance on a 5.0l?

 

[99FiveOh]

Yes, your dizzy should work fine. 5.0 motors are 50oz imbalance.

 

[98blackstallion]

Thanks man youve been alot of help! will all my 5.0 accessories bolt up fine to the 351 or do you need any adaptors? I only have one more task to really figure out for the 351 build is pushrod lenght with gt40 iron heads and head gasket thickness...woo!

 

[99FiveOh]

You'll probably be ok with stock size pushrods for GT40 irons since the GT40's are an oem head. I know you can swap GT40's onto a 302 without changing pushrods, the same would be true for 351.

Since our accessories bolt to the heads only and not the block, they'll bolt up fine. A/C compressor will probably interfere with your battery box if you keep it. Other than that, you'll have to do some trial and error on your belt size until you figure it out.

 

[BlackVert]

re the dizzy, you need to check the connector against the one from a 94/95 5.0. if the connector is the same, you are good.

 

[90fox306]

ok soo you all are saying that with a stage two trick flow cam, new springs in the heads and fresh motor in the car that with the stock heads on a 351 im only going to be able to put out the power of a 302? im having trouble believing that. i know the stock heads arent all that good and to get the most performance out of the motor i need the aluminum heads but from what i have read and talked to others that the stock heads will be fine for a while and i will only lose bout 50-75 hp from stock heads vs the aluminum ones. im running this intake edelbrock super victor. also im running the trick flow springs in the heads. i know now that i am not going to waste my money and time on porting the heads. i do agree with that but i am still having trouble getting around the fact that i will be putting out the power of a 302.

If your having trouble believing it, then dont, cause u will be making more power than a stock 302. But keep in mind that those crappy E7's are gonna hold it back quite a bit. It wont be a monster by any means wit those heads.

 

[99FiveOh]

I'd think the smaller ports and valves on the E7's will create a torque monster if nothing else. It'll definitely add to the SOTP meter!

 

[98blackstallion]

You'll probably be ok with stock size pushrods for GT40 irons since the GT40's are an oem head. I know you can swap GT40's onto a 302 without changing pushrods, the same would be true for 351.

Isn't the deck taller on the 351 those reguiring a longer pushrod?

***edit...I see what you mean. the stock 351 pushrods that motor uses NOT my stock 302 pushrods..I was thinking you meant my stock 302 rods would work...Sorry not enough coffee

 

[98blackstallion]

Can the water pumps interchange on the 5.0/5.8???

 

[ratio411]

Can the water pumps interchange on the 5.0/5.8???

Yes.

If you use your stock serpentine setup from the 5.0, just swap the water pump right along with it. I'd swap the timing cover as well myself.

If you are NOT using a serpentine setup, you need to worry about reverse rotation vs std rotation more than 5.0 vs 5.8.

 

[ratio411]

It's actually easier to tell what WON'T swap between 5.0 and 5.8.

Intake lower
Fuel rails need longer crossover hoses
Distributor
Oil pan
Just about everything inside the block
Pushrods
Head bolts
Heads if they were originally from a 5.0 unless you enlarge the head bolt holes.
Balancer from a post 82 5.0 HO is 50 oz vs 28 oz (Same with flywheel/flexplate)
The balancer/flywheel/flexplates will all interchange fine, but balance weight must be matched to engine...

Headers will bolt up fine, but may not fit chassis.

Edit
Speaking of chassis...
The 5.8 is 1" taller than the 5.0, so hood clearance is of concern.
The 5.8 is about 2" wider if memory serves...

 

[90fox306]

i disagree wholeheartedly.

stock for stock, a 351 makes alot more torque than a 302 all day.

of course, it won't realize the full potential of 351 cubic inches, which might be your point, but to say that it won't be any better than a 302 with the same parts is simply incorrect.

Exactly!!! 351 power!!!