302/331/347 engine combos

[68rustang]

Hello from the classic forum. I am looking for a website/book/resource that lists different EFI engine combos and their respective power numbers. I am looking for typical heads/cam/intake, etc.

I have a 68 coupe with a 95 GT Engine/computer/transmission. The intake has been swapped for an explorer (non-egr) upper and throttle body, gt40 lower, and long tube headers. Other than that the engine is bascally stock and runs pretty well. I would like to begin acquiring parts to build another 302 based engine to replace the one I am currently running. Be it a 302/331/347 I haven't decided yet. That is what I am looking for the resource. My primary goal is more power. The car is not drag raced, but could see the auto-x course a few times. Is it practical to use the intake combo I have with anything larger than a 302?

Thanks for any help.

 

[Pokageek]

You can do a search on this forum and should find some pretty good answers. I have a 306 high compression (flat top pistons) which is basically a bored out 302 block used to build a new engine. H/C/I 302, 306,308's are capable to put out just over 300RWHP which equals tp around 360-380FWHP and 360-400+ FWTQ. With the right gearing run 12's..unless you are really really good driver like Killer CaNAry and can get so close to an 11 sec quarter (12.03).

From what I hear, 331/347 run neck and neck with each other and get another 20-40+ HP out of the combo depending on the comb0 (correct me if I am off) but they usually see alot more TQ for some reason. And the 331 is thought is sone circles to be a longer lasting engine while the 347 makes a little bit more power. I don't know what they QM though..

Then you have the 351 and that can be bored out to a 418? Man that is big power. Expense wise, I had to go with the 306 b/c she would kill me if I spent anymore $$ and 306-331 ,meant another $1000.

 

[68rustang]

Pokageek,

Thanks for the reply. I have searched the forums quite a bit and found some good answers. I was hoping though that all the information might be compiled into one source somewhere. Any ideas of where somebody put together a best bang for your buck 302 build up?

 

[Pokageek]

Hmm... best buck might be the gt40P heads on your 302 with a big cam in my o..and a high flow intake combo like trick flow track heat or even "moss" bored out factory intake.

The e7 heads you have do not flow very well. That is prob the biggest restriction. I am suggesting you can get up to 275-280rwhp if go with the above. Again talking about "buck" you can get those gt40p's alot cheaper than trick flows and get within 30 or so HP.. Unless my engine was on it's way out, I would just change my current combo along those lines. Now if you have money you can do anything...Just one idea. To go up to a 331 or 347 is going to be alot more cash I think.

 

[BlackVert]

another option is "thumper" heads. he ports stock heads too and they flow as well as or better than gt-40s.

http://www.thumperoforangepark.com

imo, it really depends on just how agressive you want to be. there is an article in the latest 5.0 mag about a 347 that makes 500hp, but it is carb based and has a really agressive cam.

just how streetable do you want it to be?
do you intend to put on a blower?
what is your budget?

 

[68rustang]

Let me ask it this way:

Assume I stick with 302-306 cid, what would be the *best* FRPP cam/heads/tbody/maf to go with the explorer/gt40 intake I already have? Porting the intake wouldn't be a problem if necessary. How much power can I expect to make? My reasoning for trying to keep the intake is money I don't spend there could be spent elsewhere, heads, machinework, etc. However there is no point trying to save money doing that if it will be a serious bottleneck.

Now lets assume I go with 331-347 cid, will the explorer/gt40 intake flow enough for this engine?

**Best, meaning streetable, not a drag strip 3500-6500 rpm power curve.

 

[68rustang]

http://www.thumperoforangepark.com

I have thought about going that route. Though, I am leaning toward aluminum heads to get some weight off the front end. The car is a nose heavy pig.

just how streetable do you want it to be?
do you intend to put on a blower?
what is your budget?

How streetable? Not overheating in traffic or hot days, not needing a rebuild every winter, not needing to immediately beef up the rest of the driveline streetable. I should mention the rest of the driveline is a T5 and 8.8 out of a 95 GT. 300 RWHP would be great, 350 would be better, am I dreaming? I am not going to run drag tires or launch it from a standing start. Usable power curve, 2000 - 5000 rpm.

I did not intend to use a blower, maybe someday but not on this motor.

Don't have a budget, as little as possible. Like everybody else most bang for the buck.

 

[Black95GTS]

Now lets assume I go with 331-347 cid, will the explorer/gt40 intake flow enough for this engine?

**Best, meaning streetable, not a drag strip 3500-6500 rpm power curve.

302 parts on a 347 won't help you out much.

If you don't want to drop the 500 bucks for a new intake, then the thousands of dollars a stroker setup will cost you is not for you.

You're all over the place. Don't want to spend money on a new intake but will drop a cool grand at least on aluminum cylinder heads?

Whats your budget? There are plently of ways to squeeze out 1 hp / 1 ci.

Adam

 

[Pokageek]

"I have thought about going that route. Though, I am leaning toward aluminum heads to get some weight off the front end. The car is a nose heavy pig."

Yep, I forgot that's one reason I like the aluminum heads! But like Black95GTS mentioned, you are $1000-1300 on the heads right there. You can find other ways to lose the weight. That's the other issue with going 331 or 347..the trans. They put out more torque and my trans is cringing when I shift hard now...How much $$ can you spend? Again the best yo uare likely to get out of gt40p's is 260-280 with perfect matching parts.

I am not as savy as some of the others but stock MAF flows up to 300rwhp so nothing to worry about there. My ford racing throttle body-65mm flows great and I am around 300rwhp, thumper or gt40p's, explorer intake is prob fine but maybe bore it out, pulleys, cone filter, headers, h-pipe or TRUE h-flow cats, flowmaster or whatever muffler, timing bump to 15dg if it can handle it, BIG car, whatever someone else here recommends..24# injectors can't think of anything else right now but that is what I would do to get to the goal you want.

 

[68rustang]

302 parts on a 347 won't help you out much.

If you don't want to drop the 500 bucks for a new intake, then the thousands of dollars a stroker setup will cost you is not for you.

I thought the GT40/explorer/cobra upper could support a 351 without much trouble? There was a gt40 lower for the 351 a while back no?

You're all over the place. Don't want to spend money on a new intake but will drop a cool grand at least on aluminum cylinder heads?

I don't see the "all over the place." Just asking to see what parts I already have that I may be able to reuse. It is not about not spending money, it is about spending money in the right places. A few hundred bucks for iron or iron ported heads that net me some horsepower or a thousand bucks for some aluminum heads that get me the power and lose 50 lbs off the nose of the car. I don't know if you guys have paid any attention to the old cars but there is only so much that you can get rid off being that there isn't much there to start with.

I am trying to stay with bang for the buck. If I wanted a clean sheet approach I would buy a crate motor and be done.

Whats your budget? There are plently of ways to squeeze out 1 hp / 1 ci.

Adam

Can it be done naturally aspirated using my intake?

 

[Black95GTS]

I thought the GT40/explorer/cobra upper could support a 351 without much trouble? There was a gt40 lower for the 351 a while back no?



I don't see the "all over the place." Just asking to see what parts I already have that I may be able to reuse. It is not about not spending money, it is about spending money in the right places. A few hundred bucks for iron or iron ported heads that net me some horsepower or a thousand bucks for some aluminum heads that get me the power and lose 50 lbs off the nose of the car. I don't know if you guys have paid any attention to the old cars but there is only so much that you can get rid off being that there isn't much there to start with.

I am trying to stay with bang for the buck. If I wanted a clean sheet approach I would buy a crate motor and be done.



Can it be done naturally aspirated using my intake?

This is what I would do in that situation. I would bet money this would do the trick:

1 - Port the crap out of the gt40
2 - Custom Hydraulic Roller cam
3 - AFR 165 heads
4 - 75mm TB (You're gonna have to open up the intake to accept it)
5 - 80mm MAF
6 - 30 pound injectors
7 - Long tube headers
8 - off road x pipe
9 - 1 chambered mufflers
10 - custom burnt chip
11 - Underdrive pulleys
12 - 255lph fuel pump

This is a proven combo that consistently nets not only your 300 plus hp goal but also low 12 second ETs. You will also need approriate drive train and suspension mods, but that is a recipe for 300rwhp.

Adam

 

[68rustang]

Thanks Adam.

You would think that with as popular the EFI 302 is there would be a database or website that people could upload their combos into and others could browse. I know there are so many variables so it would hard to compare but it might be interesting to see.

 

[reddy351]

Thanks Adam.

You would think that with as popular the EFI 302 is there would be a database or website that people could upload their combos into and others could browse. I know there are so many variables so it would hard to compare but it might be interesting to see.

THAT's the problem. Everyones combo is a little different. You could put a supercharger on it and easily get your 300hp. Prolly for about the same $$$. Then you could sell the parts you don't need any more to recoup some of that money.

This is the nicest, most helpful bunch of guys I've talked to on the net, about cars. They really do want to help. They just need to know for certain what your goals are. Whether it's a "blood from a turnip" approach that you're after or "not wanting to buy any more parts" approach.

I would (and prolly will) try that "recipe" for 300 hp. I am also considering just slapping a supercharger on mine. Hopefully for the same effect.

 

[final5-0]

Budget Combo!

Best bang for the buck spent ........... You Say

Been there

Done that

Got the t-shirts

I did the oem parts ... self ported improvement thing ......
and
It just left me wanting more

Think about it ... you end up with a Cobra motor ... more or less

You're gonna be in a range of about 245 to 280 rwhp. All those parts are gonna start to run outta steam around 5K and fall like a rock on the way to 6K.

Its true, some do a bit better
but
They are the execption to the rule

Go poke around on my site and see my endeavors with oem stuff.

No way I'm saying oem stuff is bad or anything like that

Just pointing out ... you can only go so far with it

Most important thing to do BEFORE letting go of the green-backs is KNOW what you want or expect.

If you are looking for 300rwhp or better ............
and you go the oem route
You will most likely fall a bit short
then
You gotta lay out $$$ for that last bit of rwhp

If you want more ... just skip the stuff that won't give it to you

I really got a soft spot for those older sbf motored cars

Good Luck to you which ever way you go ...... 94 95 :SNSign:

One last thing ... Look for a chart by tmoss ... it has the combos with hp/tq values you seek.

I got it around here somewhere if you can't find it
and
I got some oem combo data as well ......... somewhere

Grady

 

[blksn955.o]

351's with gt40's are ok but the head is the bottleneck on those.

I have a setup (no solid numbers yet...but soon...soon I hope this time) that is on a good budget. I had the same back and forth issue. The setup I have would be a good 302-306 but on the small side for a 331-347. Not that it would suck and the world would blow up but it would be over and above what the H/C/I would be good for. I had a stick with it or bail head issue...I had alot of money in the gt40's already and really wanted to see what I could do with mostly stock parts...I just like the idea of what can be done with them.

D.S.S. pro bullit 306 shortblock = $2,19x.xx shipped to door

TFS1 cam = $152 shipped from summit

explorer intake = $100 local board find, ported by Tmoss (BIG thanks)

Gt40 heads = 400$...then $550 for machine shop to do springs, mill, valvejob = $950---
Thumper ported (another BIG REALLY BIG thanks) that did basicly what the $550 did AND portwork.

gaskets = $75-100

Now if you have a set of E7's and are thinking of getting some gt40's...look at the price I paid plus work and remember with any used head it is smart money to have the things done I had done by the shop the first time to get them fresh. You can get those E7's to flow better than the gt40 heads...remember NO ONE is saying they are better than AFR/TF/Edlb. alum. heads...but better than box stock gt40's. You can get that with less money than gt40s = not bad.

My old combo on the factory shortblock was the unported but shop worked gt40 heads, TFS1, and a tmoss ported stock lower. It ran the only time I had it to the track this way a 13.5 @102 with a bad...bad...bad 60ft of 2.4 or so on street tires. The ported lower was about a DEAD match to the ports of the gt40s unported ports. I was very impressed at how Tmoss has that stocker worked out it really looked like he had both the heads and the intake to match up.

You need to sit down and make up your mind 331/347 or 302-306. You need to base this on what H/C/I as a whole you can run within the budget and goals. Do the research and see if other combos work for your goals as well.

Just remember its a hobby something we do to pass the time and get some enjoyment out of after working and/or going to school so have fun.

 

[Pokageek]

One quick question..why the 30# injectors guys? II am making above 280rwhp (haven't gone back to the dyno since some big SOP changes in combo) with 24# injectors...no pinging or lean and my understanding is the 24#'s avoid a starting problem that folks with 30#r's sometimes have..any thoughts?

 

[BlackVert]

One last thing ... Look for a chart by tmoss ... it has the combos with hp/tq values you seek.

http://www.tmossporting.com/tabid/3451/Default.aspx

this might be it ...

 

[tmoss]

Probably the one below - hold you mouse pointer over the bottom of the pic and click on the popup to get the full size view.

http://forums.stangnet.com/attachment.php?attachmentid=42558&d=1139595600

 

[final5-0]

Probably the one below - hold you mouse pointer over the bottom of the pic and click on the popup to get the full size view.

http://forums.stangnet.com/attachment.php?attachmentid=42558&d=1139595600

That is indeed the exact one I was talking about Tom

Excellent job you did on that chart MR. M

I do know you spent lots of time putting it together

I find it so very strange that it surfaces from time to time and NO ONE seems to recognize or appreciate its value by the fact the same Q gets asked over and over.

COME ON my SN friends this is a wealth of info which ... I might point out ... you didn't even have to put forth any effort to have all this data at your disposal

Treat it for what it is ...... VALUABLE ...... save it to your hd

Sorry folks

I just had to get that out

I'm done now

Grady

 

[tmoss]

I'm going to update that one in the next few days. I have a LOT of dyno tests tucked away on my hard drive.