[Dr Evil]

Hey everyone - Been more than a few years since I've checked out the site! Glad to see it is still up and as popular as ever Is Jon still running the place?

Anyway I've got some crazy ideas running around in my head with the direction I want to go with my 70 Fastback. I've always wanted an original Boss 429, but couldn't justify 1: the price they are going for, and 2: I've already got a 1970 M-Code Fastback (first car bought back in high school). So, I think I've decided to just build a B-9 clone with the car I've already got in my garage. I realize there are issues with the shock towers and mounts, and they will be address accordingly. My concerns are how much HP can the stock 70 unibody handle? I am thinking the motor will be in the 750hp range. I have recently put in a 4-link rear, and have TCP front coilover / rack & pinion kits to go in after it gets painted with the new engine. I will contact TCP about clearance issues with their kits and the Boss engine. Is 700+HP too much for this stock chassis? Also, the car currently has a 351C/C4 combo in it. Will a built C-6 handle the power? Or would I be better off swapping in say a T-5?
Anyway any input would be great. The car is going in for paint soon, and I would like go get started on the engine build. I am shooting for August 2014 for it to be together enough to drive.
Thanks!

 

[jjmstang]

You will need atleast a ten point cage to keep the body from twisting, especially if you go to the track and use slicks.

 

[PSIG]

The question of power-handling is how much you can put to the pavement. In a general sense, 1000hp doesn't matter unless you can get traction for it. So, if it's a street-tire car, then just sub-frames and a 6-point would do, as you wont have to resist more than maybe 300-400 ft/lb of actual torque transfer. DOT radials? Slicks? Then, yes, you'll have to beef appropriately.

Forget the T5 at that level. The C4 and C6 can be built to handle that power reliably either street or strip. There are other options for manuals and autos that skyrocket in price from there. If you don't need more gears or OD, then I'd stick with one of those.

BTW - the B429 has fantastic flow with a horrible chamber, and it's difficult to run pump gas without early detonation. Be sure to account for that if intending to run pump gas, and especially cam timing to avoid det at lower revs with higher loads. 91 octane is borderline with a stock homologation (factory street) setup. HTH

David

 

[Dr Evil]

The question of power-handling is how much you can put to the pavement. In a general sense, 1000hp doesn't matter unless you can get traction for it. So, if it's a street-tire car, then just sub-frames and a 6-point would do, as you wont have to resist more than maybe 300-400 ft/lb of actual torque transfer. DOT radials? Slicks? Then, yes, you'll have to beef appropriately.

Forget the T5 at that level. The C4 and C6 can be built to handle that power reliably either street or strip. There are other options for manuals and autos that skyrocket in price from there. If you don't need more gears or OD, then I'd stick with one of those.

BTW - the B429 has fantastic flow with a horrible chamber, and it's difficult to run pump gas without early detonation. Be sure to account for that if intending to run pump gas, and especially cam timing to avoid det at lower revs with higher loads. 91 octane is borderline with a stock homologation (factory street) setup. HTH

David

Thanks for the input guys, that is exactly what I was looking for.

I am going with the Kaase heads, so hopefully that will help with detonation problem. I have no problem running VP93 or 100, as its available at the pump about 8 miles from home. It won't be a road trip car, so I don't mind paying a little extra for quality fuel.

I have a HD C-4 that I was running behind my Cleveland. Would that bell housing / flywheel / TC work on the back of the B-9? The block will be a standard 429/460, and not an original B-9 if that makes a difference. I would go through the C-4 and upgrade essential parts before bolting it behind the Boss.

Looks like a cage is in order then. I can't get subframe connectors to work because the car is 4-linked in the back, and the forward link brackets are fixed where the Global West subframe connectors need to mount. I didn't even think about that until I bought the connectors and went to fit them after I put in the 4-link.

Is the shock tower swap fairly straight forward? I am new to bodywork, and want to attempt it myself, but don't want to get in over my head. I would get a set of aftermarket towers that are ready to go in.

Thanks!