Need info on heads and hp

[mikem 13]

I really need some guidance on how to get close to 300 rwhp with decent torque. I had my 302 2v engine long blocked by a professional builder/machine shop. I told him I wanted as close to 300 hp as possible but still be streetable enough for a daily driver and being able to use the air conditioning. After about a 1k mile break in, i took it to the dyno and i have 218 rwhp. It runs well, but not well enough. Know what i mean? Here is what i have:

302 with stock 2v heads that were ported and stainless steel valves

Forged TRW dished pistons. I believe I have about 9.3 compression ratio.

Comp cam, but i dont know which one and he didnt save the cam card for me. It has a little bit of lumpity lump to it at idle. Maybe a 268H.

Performer Intake, 670 Street Avenger carb, and Patriot Clipster shorty headers.

It currently has a C-4 with 3:00 open rear end.

 

My question is, how do i get the other 80 horses and yet still have a totally streetable engine? I was thinking about the 165 AFR aluminum heads and the RPM intake hoping for maybe 40 of those horses?

 

My one month plan is to add whatever power package i get suggestions on to get 300 hp, then in January 09, install the 1989 AOD i got out of a truck (rebuilt with TCI kit and B&M 13" locking converter 1900 to 2100 stall), and a 3:73 or 4:11 traction loc third member.

 

I'm not a street racer but I would like to have a car that runs almost as aggressive as the 69 looks. Any ideas, suggestions, help would be greatly appreciated. I promise to follow through and post the results. Mike

[mikem 13]

Nothin........???

[Pakrat 1,043]

Stroke it or squirt it.

[flight96 14]

According to Ford Racing...

 

"GT-40X XTRA PERFORMANCE “TURBO-SWIRL†ALUMINUM CYLINDER HEADS - THE FAST, EASY WAY TO BOLT ON 65 HORSEPOWER! TRUE BOLT-ON PERFORMANCE"

 

Its no 80HP but 65 extra is nothing to sneeze at !! I'm considering these if I rebuild my 351w.

[d.reese 13]

I agree with Pac on the squirt, due to the low compression pistions. Not sure if the bottom end built for 300rwhp would take it though?

 

Think about it, you built a motor and asked 300 rwhp and didn't dyno the motor before hand? I say the the mach shop got as close to the fact as they could with out the prior knowledge of HP at the flywheel.

 

Flight is on to some nice stuff, but go back and see what type HP it takes to get rwhp.

 

The reason I say that is the 80 at the rwhp could take anothe 120 from the motor. The heads are 65 hp at the motor.

[mikem 13]

Thanks Flight 96, i will check these out. I could settle for 65 horses.

 

I couldn't dyno the car before hand. When I bought it, it had burnt valves and ran terribly. I guess i presumed too much in asking an engine builder to give me 300 horsepower. I thought he would know the combination needed to pull that off or at least present some options or drawbacks to the options. I will do more research on the GT40x heads verses the AFR heads. Maybe with the new heads and a gear swap from 3:00 to 3:73 will be enough to keep me smiling for awhile. Thanks for the input.

[Pakrat 1,043]

I've always been an advocate that the assometer is equal to or better than the dynometer when building a cruiser. I've been in little rice boxes that could probably beat my 302 but they sounded and felt horrible to me and those same people have been in my car and when that loud growl hits, the tires chirp and the front end raises and their butt sinks in the seat they have been like "dude, this thing kicks ass".

[69RavenConv 286]

Like flight said, a head swap is a quick, easy way to add HP. The stock '69 302 heads are a definite weak link when it comes to making HP. So if more HP is your goal, I'd definitely recommend new heads. Most any of the wide assortment of late model 5.0L performance heads will make a big difference. I've heard good things about the GT40 heads, too.

 

Beyond that, you've got to go to a wilder cam, taller pistons, stroker kit, supercharger, bottle, you get the idea. Time and money. Heads you can do on a Saturday at home.

 

I would bet that better heads and 3.73 gears will give you a very noticeable improvement and still be very streetable. But probably not 300 hp at the wheels.

[Max Power 74]

Thanks Flight 96, i will check these out. I could settle for 65 horses.

 

I couldn't dyno the car before hand. When I bought it, it had burnt valves and ran terribly. I guess i presumed too much in asking an engine builder to give me 300 horsepower. I thought he would know the combination needed to pull that off or at least present some options or drawbacks to the options. I will do more research on the GT40x heads verses the AFR heads. Maybe with the new heads and a gear swap from 3:00 to 3:73 will be enough to keep me smiling for awhile. Thanks for the input.

 

 

Sounds like he probably got you 275 at the flywheel. Not bad considering the suck factor of factory heads.

 

I would get a set of Performer RPM heads with the 1.90 intakes and the matching intake. The 1.90 intakes should clear your pistons, the heads are top not for bolt holes with steel inserts for brackets and such, and you will be close to your 300 rwhp. Get some 3.50 gears and you will feel like you are definitely there.

[Cheo69GT 1]

I agree with the Performer RPMs and the AFRs. I found a complete used set of Performers at a Mustang show for $650, save you some money. Might want to get a cam to match them too.

[d.reese 13]

Yea, heads - cam and gears. All for well under 1,500 and hang on Salley. With a little help done in a day. Yep you'd see a marked improvement in performance and sound of life under that hood.

[Pakrat 1,043]

There is always the older school cheaper method too which is to upgrade to 351W heads, that's what I have on my 302 and along with the Weind intake, 4V Holley carb, upgraded CAM and long tube headers it's got all the go I have ever needed.

[ammosteve 10]

What you are asking for isn't too difficult but you won't get there with stock 302/351 heads.

 

I'm assuming that since you just had the bottom end built you would like to stay with it. Stroking would be one option but your goal can be met with 302/306 cubic inches.

 

One single part won't get you there. You will need heads and a cam.

 

If dead set on buying AFRs then opt for the 185s instead of the 165s. There are better choices out there though....

 

I would buy either Canfield or Trickflow but AFRs will get you there.

 

You will need a cam to pull it together. A custom cam can offer driveability, performance and decent economy.

 

If you are interested I will give you a name of someone who can help.

 

Steve

[69again 10]

Pak, right on the money. Nothing beats sound and feel of a v8.

Mikem,

It won’t increase your hp, but 3.25-3.55 rear gears will increase the feel of torque considerable and let your engine get up in the hp range, especially when you get on it. I would consider that first because if you build the engine the way you think you want, you will need different gears anyway.

If you really want a street able 300rwhp out of a 302, you will have a challenge. We took our 302 bored it 30 over, forged SRP pistons, had the bottom end balanced, put the Edlebrock rpm performer package, big cam here (a lot of rumble), 750cfm carb, long tube headers, magnaflow 2.5 stainless exhaust, a built c-4 with 3000 stall converter and 3.55 rear gears.

Edlebrock says 375 at the engine. We did two dyno’s, we hit the numbers on the engine dyno, but on a chassis dyno, we were only 285hp at 5500rpm.

We drive it as a daily driver and it seems to do ok, but it really is rough at idle, 850rpm, in gear, which is high. The mirrors shake considerably.

That being said, you cannot floor this thing from a dead stop without breaking the rear wheels loose.