How much HP needed?

Topic: How much HP needed? (Read 2772 times) previous topic - next topic

How much HP needed?

April 17, 2006, 12:13:40 AM

I'm getting ready to do a 351w swap into my 86 cougar, I was wondering how much hp to build my motor to get my car into the mid to low 12's. I don't want to strip my car down to lose weight so I know right there I will need more power. I will be running a 8.8 rear end with either 3.73 or 4.11 gears just depends if I run a c6 or a built AOD tranny. I will be putting stock heads that are ported on right now then down the road a set of either Edlebrok rpm heads or AFR 185's. I'm ordering some BBK full length headers for it I think there 1 3/4 or 1 5/8 primirys. My best guess right now is that I need around 400hp at the crank, does that sound about right if not let me know. Forgot I well be running a carb setup with a 750cfm and a Rpm air gap intake or weind stealth.

How much HP needed?

Reply #1 – April 17, 2006, 03:18:00 AM

well.. my suggestion is to go with an x303 cam, the air gap and the AFR heads.. go with a C6, you may lose overdrive, but it'll be bullitproof.. whether stock or worked.

also, not to forget torque converter.. they factor in big time..i'd go with a 2800 stall converter for what you're building

How much HP needed?

Reply #2 – April 17, 2006, 10:44:17 AM

Good advice but, I don't think he'll really need a C6. A C4 can handle the abuse of a 351 in a 12 second 3500 pound car. A C6 is stronger no doubt but much heavier and much less efficient. Me, I'd beef up an AOD but, I like having the overdrive.....

The air gap is an excellent carbed manifold for the windsor motors.

How much HP needed?

Reply #3 – April 17, 2006, 11:02:17 AM

I was reading recently that in heavy HP conditions the C6 will draw not much more power than a C4 & will ultimately slip less & be more reliable. These people claim to have tested out their theory in the real world as opposed to a power bench that puts an unrealistically low load on the tranny. In a heavy car it may not hurt as much as rumor has it.

There are cams that are much more optimised than the X303 for a 351 also. You can pretty much be assured of reaching your goal if you get a custom cam matched to your combination, but if not there are more optimal cam designs from Trick-flow Comp etc that will get the most out of those heads/exhaust combination.

How much HP needed?

Reply #4 – April 17, 2006, 02:25:34 PM

It's all(or mostly)in the heads... Under ideal conditions, my fat girl, stock bore, Trick Flow headed/cammed 5.0 has gone 13.11@105. Even with a 351, you'll need some really well ported heads to get those numbers in a full weight car. With good heads, 12s will be easy...

I went 12.23@112.2 with a 90 shot of nitrous. In a 3700 lb car(with driver), that figures to be approx 440-450 flywheel hp.

How much HP needed?

Reply #5 – April 17, 2006, 07:28:23 PM

Well the headers that I wanted to use will only fit manuel tranny so guess I have to use shortys. BBK headers from jegs are $219 is that a good price? I talk to my brother-in-law last night and he said I should build a motor that has good street maners around 300-350hp and use a 2 stage nos kit to get me into the 12's He works for one of the biggest machine shops in Springfeild Mo. so he probable knows more then me about this.

How much HP needed?

Reply #6 – April 18, 2006, 12:03:41 AM

Go with the tranny you want to go with. all 3 of those tranny can hold a 12 second car easy and if your spending easy money talk to your local HiPo tranny garage he probably tell you the same, and in a lot of cases they can build them for a lot less HP loss threw them.

How much HP needed?

Reply #7 – April 18, 2006, 05:53:38 AM

Make sure you get the 1 5/8 headers since you'll be going shorty.