horsepower

littlewave · #1 (**permalink**) 03-15-2011, 07:32 AM

Horsepower in question. I was told I had 365-375 hp but I think it's more. I have a 351w with Hypereutectic heavy duty pistons appro.9to1 comp.Blue racer hydraulic cam,Edelbrock rpm heads 202in 160ex,Edelbrock dual plane intake,and an Edelbrock 750 carburetor. I myself was thinking this combo was closer to 400. Any input from you guys would be appreciated. Thanks.

Ron61 · #2 (**permalink**) 03-15-2011, 08:00 AM

That probably isn't to far off the mark. Your compression will cost you a little power and you didn't say if you have a high rise or low rise intake. Also did you have the heads ported and polished. That would pick up some power depending on how well they are from the factory. Since you never said anything about it I am guessing the engine isn't a stroker. You could get 400 horse from that set up easy enough.

Ron

littlewave · #3 (**permalink**) 03-15-2011, 08:36 AM

No not a stroker. Low rise intake, but I do think the compression is closer to 9.5 to 1 because of the alum. heads. Heads are stock out of the box.

Wbulk · #4 (**permalink**) 03-15-2011, 08:51 AM

While heads, Compression ratio, intake, and carb are very important, the most is the cam. You don't give the specs on the cam. What is the duration at .050 ? What is the lift?

Jerry Clayton · #5 (**permalink**) 03-15-2011, 08:51 AM

I dought that you make anywhere near that much hp

Ron61 · #6 (**permalink**) 03-15-2011, 10:45 AM

Quote:

Originally Posted by Jerry Clayton

I dought that you make anywhere near that much hp

Jerry,

We had a man here that built a Cobra some years ago and he used a basically stock 351 and a little better cam and had the heads ported and polished with a high riser intake and his dynoed out at 407 horsepower. I can't use mine as an example because it was a stroker and had a lot of work done to it for racing and it put out right at 530 horse with 507 pound torque.

Ron

Z-linkCobra · #7 (**permalink**) 03-15-2011, 11:10 AM

Quote:

Originally Posted by Jerry Clayton

I dought that you make anywhere near that much hp

I have to agree with Jerry. Stock untouched aluminum heads..not much of a gain in hp there. 9:1 compression...mild. Then you put an Edlebrock carb on top of it...that killed any chance youhad of making any hp....lol. Sorry I dont like anything but Holleys.

I would say somewhere in the 350 to 370 range.

Just my 2 cents worth.

Gene

Ron61 · #8 (**permalink**) 03-15-2011, 11:16 AM

Quote:

Originally Posted by Z-linkCobra

I have to agree with Jerry. Stock untouched aluminum heads..not much of a gain in hp there. 9:1 compression...mild. Then you put an Edlebrock carb on top of it...that killed any chance youhad of making any hp....lol. Sorry I dont like anything but Holleys.

I would say somewhere in the 350 to 370 range.

Just my 2 cents worth.

Gene

I have to agree with you on this. I overlooked the Edelbrock carb and mild cam. I had a 900 double pumper Holly on mine and the man that I referenced above used a Holly carb and as I stated, went to a better cam and had the heads done. I think his compression was 10:1 also.

Ron

YerDugliness · #9 (**permalink**) 03-15-2011, 01:36 PM

Quote:

Originally Posted by Z-linkCobra

I have to agree with Jerry. Stock untouched aluminum heads..not much of a gain in hp there. 9:1 compression...mild. Then you put an Edlebrock carb on top of it...that killed any chance youhad of making any hp....lol. Sorry I dont like anything but Holleys.

Gene

Gotta disagree with ya, Gene, about the Holley issue. I had a Holley on my (most likely) box stock 5.0HO in my cobra, it ran poorly, so instead of replacing it with another Holley I let them talk me into putting on an Edelbrock Thunder carb. Now it will run rings around what it use to do. No bog, no sputtering, just solid accelleration.

Having said that, though, I must admit that the IRS return is going to be spent for a "Holley-like" carb, a Quick Fuel model. I think the real issue with the old Holley was that it was just waaaay too big for the engine. It was a 780CFM model, the Edelbrock is only about 575CFM, I think. The Quick Fuel will be in the 600-650 CFM range.

The compression issue is what is keeping your HP down, IMHO.

Cheers from Dugly

littlewave · #10 (**permalink**) 03-15-2011, 02:11 PM

Jerry how much do you think I have? 175

littlewave · #11 (**permalink**) 03-15-2011, 02:38 PM

wbulk, 520 lift 280 duration.

Z-linkCobra · #12 (**permalink**) 03-15-2011, 03:43 PM

Quote:

Originally Posted by YerDugliness

Gotta disagree with ya, Gene, about the Holley issue. I had a Holley on my (most likely) box stock 5.0HO in my cobra, it ran poorly, so instead of replacing it with another Holley I let them talk me into putting on an Edelbrock Thunder carb. Now it will run rings around what it use to do. No bog, no sputtering, just solid accelleration.

Having said that, though, I must admit that the IRS return is going to be spent for a "Holley-like" carb, a Quick Fuel model. I think the real issue with the old Holley was that it was just waaaay too big for the engine. It was a 780CFM model, the Edelbrock is only about 575CFM, I think. The Quick Fuel will be in the 600-650 CFM range.

The compression issue is what is keeping your HP down, IMHO.

Cheers from Dugly

Well see...you aint comparing apples to apples. You went down in CFM and got better performance...not the carbs fault that your motor was too small........lol.

Believe me the last thing I want to do is start a war about which carbs are the best. I wouldnt use a quadrajunk for anything but weighing down a crab pot...but I know guys that wouldnt run anything else. Maybe I cant tune anything else...lol.

Gene

vector1 · #13 (**permalink**) 03-15-2011, 09:28 AM

one of ford's crate 351 is rated at 385hp

Jerry Clayton · #14 (**permalink**) 03-15-2011, 02:37 PM

maybe 225, would be easier if we knew some specs on cam

Wbulk · #15 (**permalink**) 03-15-2011, 03:26 PM

That 280 must be advertised duration. So it must be in the 212-220 range at .050 depending if the specs were .004 or .006. I think the lower range is correct and maybe that is a tad high. And yes if that Edelbrock is set up right it is a good carb. They both have their issues. But it sure is easier to change jets.

littlewave · #16 (**permalink**) 03-15-2011, 04:00 PM

Wbulk, yeah i think 212-220, but someone said 225hp. Really! Anyone else think it's that low? I hope to be on the road in May and want to dyno it and find out for sure!! I'll pass nubbers on when I get them.

As for the Holly( I don't want to start any thing either on carbs) but I had one on my 69 Vette 350/350 hp(and yes 350hp match# car) put a new Holly on and it was horrible.

thanks litt. wav.

392cobra · #17 (**permalink**) 03-15-2011, 04:41 PM

Quote:

Originally Posted by littlewave

Wbulk, yeah i think 212-220, but someone said 225hp. Really!
thanks litt. wav.

Was it a buddy that told you 225hp ? Must have been trying to make you feel better about it.

Do you have many hills there you have to get over ? Get the right rear end gears and you should be fine.

littlewave · #18 (**permalink**) 03-15-2011, 04:59 PM

392 cobra, no someone on here(not that I'm up set about it) just think that is way off. As for gears 3.50s in a 9" narrowed to 56" and a 4 link with strange 31 spline axels and Alden coil overs. Wilwood ultra light 4 piston calipers. 12.19 on the rear 11.75 up front.

DAVID GAGNARD · #19 (**permalink**) 03-15-2011, 06:31 PM

Quote:

Originally Posted by littlewave

Wbulk, yeah i think 212-220, but someone said 225hp. Really! Anyone else think it's that low? I hope to be on the road in May and want to dyno it and find out for sure!! I'll pass nubbers on when I get them.

As for the Holly( I don't want to start any thing either on carbs) but I had one on my 69 Vette 350/350 hp(and yes 350hp match# car) put a new Holly on and it was horrible.

thanks litt. wav.

Showroom stock 351-W's from 1969 to 1974 were rated at 250hp from the factory with a 2 barrell carb.....later 'smog" engines were down in the 200hp range......
Add in your Edelbrock heads/intake/cam, I'd guess 300 to 325hp...
BTW: the Edlebrock heads are good out of the box,but with a few hours with a die grinder, they can be a lot better....Ever see one out of the box???? Some are terrible as far as casting crappola in the ports, it takes very little work and time to really clean them up and port match them and the gains are well worth the effort....
Ford small blocks also responde well to higher compression ratios...

Clean up the heads and cut a few thousandths off them to increase compression to say 10 to 1,add a 650 double pumper Holley and your set-up is certainly capable of 400 hp........IMHO of course.....

David

MAStuart · #20 (**permalink**) 03-15-2011, 06:23 PM

Hi Guys, It seems like you don't have a lot of faith in a small block ford. I would think you could make that kind of horsepower (351ci, 350-375horsepower)with stock iron heads. What kind of a small block would it take to make my 65 stick shift Mustang to run 12:90 to 13:10? 30 0ver 302 and must be able to run on piss water, what gears too? By the way it weighs about 3250. Need to be able to drive it 150 mile round trip to the track. Thanks