Torque and Frame

[Cozmolyne]

Hi everyone,

So, as you could tell I'm new here and I'm definitely going to be posting more as my father and I are just about to start work on his 68 Firebird convertible. I don't know to much about cars beyond the basics so I'll be coming to you guys a lot and working on this Bird will help fix that.



Anyways, enough introductions.

So right now my father has a rebuilt '77 400 Big Block that doesn't have but 30 miles on it. He's going to get some headers that he says will give the engine about 430hp. I asked him why not more and he says anything beyond that would bend the frame because it doesn't have a hardtop to reinforce it. Granted 430hp is plenty but I'm worried if 430hp would be too much. What are the limits of our Firebird's frame. Is 430hp too much, or can it handle more than that? If so, how much more can it handle?

P.S. Please forgive me if this topic has been beat to death. I checked 6 pages back and didn't see a similar thread.

[Schwartz Performance]

In any case, at least subframe connectors would be recommended... But if he's not beating the car up on the track or anything it'll probably be ok.

-Dale

[mitch_04]

I'm assuming the 400 has more than just headers to give it 430 HP. It would take a decent cam/head/intake package to reach those numbers especially if it is measure at the wheels. If you are concerned, do like Schwartz says and put some subframe connectors on. They are relatively inexpensive and will stiffen things up quite nicely. Also, you might have better luck checking the suspension section for this kind of information, it's not quite Advanced Tech and Performance, IMO. It would probably be more seen in the suspension section as well.

A little more information on the engine build would be helpful as well. Intake, heads, cam, etc etc...

[Cozmolyne]

I'm assuming the 400 has more than just headers to give it 430 HP. It would take a decent cam/head/intake package to reach those numbers especially if it is measure at the wheels. If you are concerned, do like Schwartz says and put some subframe connectors on. They are relatively inexpensive and will stiffen things up quite nicely. Also, you might have better luck checking the suspension section for this kind of information, it's not quite Advanced Tech and Performance, IMO. It would probably be more seen in the suspension section as well.

A little more information on the engine build would be helpful as well. Intake, heads, cam, etc etc...

The block is 40 over, has 1978 heads ported and polished, Sig Erson Camshaft not sure of lift or duration, 9 and 1/2 to one pistons, mid rise intake, poly 750 carborator.