331 1969 Stroker!

[John Grunwald]

Hey guys! Im working on a 331 stroker right now and i need some advice..
well first of all how much power do you think this will be making with these mods..
-e303 cam
-1.7 lift roller rockers
-9.8:1 compression with 64cc Gt40 heads
-1987 mustang gt intake manifold with 32lb inj
-forged rods and pistons with stroker crank
-has a megasquirt v2 computer
-tri-headers
probs some others i left out...
any suggestions? Hoping to get around 400 horses when im done with the whole thing...
also i need suggestions on the rear end because i havent even started with that yet... its gonna be a street/strip not complete strip so dont get too crazy

 

[bikefreak600]

real world expectations should be around 300-310. you were off to a good start going the stroker route. but then you said gt40, those are barely better than stock. actually they are stock on cobras and explorer motors and they make like what 15 more h.p than stock 5 liter. if your goals are anything higher than 350 + naturally aspirated then first thing should be looking into aftermarket heads. e7 or gt40 heads will not cut it.

just google "331 stroker gt40 heads dyno numbers" and you will find thousands who found the hard way that 300 hp range is the limit with stock heads

 

[John Grunwald]

What if I ported the heads? And what's a good aftermarket set of race heads?

 

[bikefreak600]

honestly any aftermarket head would be better than ported gt40 heads. if you want more power sell the gt40 and put that money toward a better set. if you want 400 hp then all you need is a cheaper set of heads. AFR185, trickflows, edelbrock performer RPM, RHS, world, patriot performance, ANY one of these brands will make 400 hp. all around $1000-$1300

if you want to step up to something that will support MUCH more power, you might be searching for more power down the road ( when 400hp is no longer enough) then look for a CNC race head. these usually start around $2000 you will want to look for 205cc intake runners and larger. AFR205 & trickflow 205 cnc are popular for the money.

 

[331efiblue66]

Anything over stock displacement you are wasting time & money with stock head castings, ported or not. I would get away from Fords 'letter' cams for any strokers too. Too many better options out there, more tailored to a stroker and not much more $$.

 

[68keyblr]

I built a 331 for my '88 GT a few years ago, similar to the combo you are looking at. I was pretty happy with the results, but the GT-40 heads, although ported and better than stock, held the combo back.

I would definitely recommend a better cam than E303...that's way too small for a 331. To get the most out of your combo you might consider going with a custom cam from Ed Curtis, Buddy Rawls, etc. Comp Cams XE 282 HR is a good off the shelf cam for a 331/347 street enging. Definitely spend the money on heads though!

 

[John Grunwald]

Well i decided to buy some aluminum heads... they are 210cc intake and have a 60cc combustion chamber what would be a good combo on the cam? Thanks for all the help guys! and also i have a gt40 intake manifold im guessing im probaly goin to need a better one? any suggestions? Thanks!!

 

[68keyblr]

If I could make a suggestion - contact a custom cam designer like Ed Curtis (http://www.flowtechinduction.com/) and tell him your goals. He will then be able to design the cam and select the heads and intake that will all match and give you the maximum performance.

If you don't carefully match the heads, intake, and cam, you will be disappointed with the results.

 

[John Grunwald]

Thank you!

 

[Rick 91GT]

Whos heads are they? What brand?

I did a 333ci, with oob AFR185s, untouched cobra intake and made 383/404 to the tire on a mustang dyno, custom cam I came up with.

 

[jerthemost]

I recently upgraded my 68 coupe 289 and used the Edelbrock matched 321/347 package and it runs beautifully. I supposedly have a 289 but it turned out to be a 302 block. They used 302's somewhere mid year in 68. I also used Comp Cams aluminum roller rockers and I have a performer 289 intake and Edelbrock carb. All of the Edelbrock stuff is matched to work together and it does perform. I also have the Floewmaster 40's on it and it never fails to get lot's of comments when I go to town. Everyone loves the sound. I highly recommend the Edelbrock package. Just make sure to use all they recommend like the timing set and hardened push rods from Edelbrock. Then if you have a problem they will back it up.

 

[69gmachine]

Well i decided to buy some aluminum heads... they are 210cc intake and have a 60cc combustion chamber what would be a good combo on the cam? Thanks for all the help guys! and also i have a gt40 intake manifold im guessing im probaly goin to need a better one? any suggestions? Thanks!!

I think 210s would be too far in the other extreme. With fairly low compression and a smallish intake, those heads are too big for the combinatin to work well anywhere. Something in the range of AFR 185s or TW190s would be a huge improvement over stock and work well in a normal RPM range. I would also bump the compression up to around 10:1 if it's not too late.

 

[bikefreak600]

I think 210s would be too far in the other extreme. With fairly low compression and a smallish intake, those heads are too big for the combinatin to work well anywhere. Something in the range of AFR 185s or TW190s would be a huge improvement over stock and work well in a normal RPM range. I would also bump the compression up to around 10:1 if it's not too late.

no such thing as too large of cylinder head. the only thing that can harm him is too low of compression. huge heads on a stock engine will run the same as stock engine except more power everywhere !