What would it take to run 12.8xx?

[uhoh5.0]

I was wondering about how much rwhp you think would be necessary to propel a 66' coupe into the 12's. I have just some rough numbers to go off of like ~2800 lb curb weight (I could be way off on this), and I'm thinking about 300rwhp??? Maybe someone can chime in with their successful combo's.
Thanks

 

[coolblue65]

300 rwhp and good tires will definately get you there.

I have over 300rwhp, my best on street tires was 13.2, putting on drag radials dropped me a half second right off the bat with no practice on them.

 

[uhoh5.0]

You have a pretty nice combo there, best of the best. I bet you could squeeze a lot more out of the quarter if that was the desire. I'm getting ready to build my motor and I'm just trying to get some first hand experience of combo's that have worked well. This will primarily be a street car, with maybe a couple passes down the track each year. Here are the parts I have accumulated, and those that i am considering:

Have:
-Ported GT-40P heads with Crane 1.6 aluminum RR's
-Stock 5.0 that will need freshened up, may end up going .030 over to yield 306cu in
-Edelbrock Performer Intake

Need/Considering:
~650 cfm carb, thinking about the Holley 660cfm Street Avenger
-Choosing a Cam, thinking about TFS stage 1, Anderson Ford Motorsport, Comp

And that is pretty much it, the car has an 8" rear with Traction Lok Posi and 3.55 gears, and a C4. I will be replacing the converter after I see where the torque curve of the motor falls. Probably somewhere around 2500 rpm stall

 

[Z06killinSBF]

Good luck with the P heads, not sure what headers will fit them. You could prob run 12's with ported/milled stock heads, better intake, cam from above, 4.10's, drag shocks/springs and stickies. If that doesn't get you there, a 150 shot will.

 

[phutch11]

I have the p heads and will be buying some MAC true flow headers soon to replace the heavily massaged tri-ys on the car right now.

Supposedly they will fit with 90 degree boots and a little love from a BFH.

Ill post the results when complete.

You may want to consider some Caltracs, people say they will really help you hook. That and some good drag radials ought to be all you need for traction.

Good luck....

 

[uhoh5.0]

Good info! I was just thinking of using the FRPP headers that they say are designed to fit with the P heads for shortys. I thought most longtubes would fit anyways?

 

[Z06killinSBF]

Do they make the FRPP's to fit the early cars? The fox style headers wont work.

 

[uhoh5.0]

I didn't know that. You said you are using some modified tri-y's? how bad was that? I know a guy that actually builds headers, but I'm thinking if I could start with something close he could work them for me fairly easily. I really just want to use a cheap, painted set of long tubes like hookers or hedman something like that. $150 bucks or so and then try to modify from that.

 

[65FBE2]

Before I built the current 347, I had a 289 in a 66 coup that ran 12.84. The motor was very mild with dead stock 289 heads, crower solid cam .512 lift [email protected], F4B edelbrock, 650 DP Holley and long tube 1.5 primary headers. The trick was the drive train The car ran 14.8's with stock 2.8 rear gear. At the end I had 4.57 gear, 30lb steel flywheel, 70/30 front drag shocks and a 2.72 first gear wide ratio top loader and slicks. I ajusted the air in the slicks until the car lanched without a bog. My motor was lucky to make 275 hp. The combo was not very streetable. If I were trying to get into the 12's with a street car, build a budget 347 or if thats to much, go for a topend kit from edelbrock for your current motor. You WILL break the 8" rear end with slicks garanteed! Your going to need about a 2800-3000 stall converter. It would be a lot easier and more streetable with a T5z 5-speed and 3.7 gear

 

[uhoh5.0]

I appreciate the info. The car will be 99% street driven, but I would like to be able to run it down the strip occassionally

 

[Z06killinSBF]

25" tire + 3.80's + C4 = 3500rpm highway speeds. Not fun.

I've heard the MAC headers are easier to work with on the P heads. Just don't expect more than 300 hp on the P's. I was told once that stock parts make stock power. If you can ditch those heads and pick something better up, you can run your cheapy headers. I actually have a set of OLD long tubes that are all beat up just taking up space.