I've read about a lot of folks building for 600WHP+ with great interest, but I've never read anything referring to their installation of bracing to shore up the stock platform. Anybody concerned about driving home from the track with one of your front wheels hanging up in the air due to a bent chassis? Is this a valid concern with a high HP/TQ built engine, or not?

 

There has been a few people who have broken the 800whp barrier and I dont believe that they have had any problems. I wouldnt think it is a big problem to be honest with you. Maybe once you throw solid engine mounts and tranny mounts into the mix you could possibly have problems depending on how hight the hp is but as of right now I would think that it is not a big concern with the numbers that people are seeing.

 

Bending the chassis is more of a factor when you get amazing grip and take off the line w/ a 1.3 or lower 60'. As of now, i dont know any street Z that's broken 1.45 60'.

 

I'm not disagreeing with you here, but "a few years back", one of my friends told me a story about a Chevy Vega that had a 350 short block crammed into it. Of course, the Vega was never designed to run with a 350 short block. I was told the Vega's first shot off the line torqued that car so hard, he drove home from the track with one of his front tires gliding above the road. I can believe the story, but maybe it was just a fairy tale. I do not know.

I hurry to add I realize the Z/G chassis is a much more modern example than the Vega's of yore... but, I still wonder if going from 280HP to 600HP+ on a Z/G could induce a significant deflection, enough to cause things to bend [and stay bent]?

 

Hm i see what you mean. I was thinking mostly in chassis flex from bumper to bumper rather than laterally. Your story sounds pretty realistic concidering a 350ci puts out a lot of torque.

 

My 500 WHP+ Z Roadster was twisted like crazy. I tracked the hell out of the car, but never wrecked it. We haven't experience the same with Coupes or G35Cs with high horsepower. However, we do reinforce the suspension and have even developed customer strut tower braces for the G35C to handle better and provide stability.

Good luck.

M

 

MraTurbo,

Have you guys ever put a undercarriage brace together to reinforce the roadster? Were you guys running a cage on the roadster and it was still twisted..?

I am pushing 500 and getting to the point of concern about twisting the frame.... I have plans for a lot more HP with my new engine so I need to put some planning into this.

Thoughts.

Thanks,
--B

 

Is it a Coupe or Roadster?

Don't get me wrong, the roadster is extremely cool, yet just not the best track or HUGE WHP car. Talking more than 500 WHP and 600 FT/LBS Torque.

I recently got rid of the Roadster because of this. We did build an additional brace in the middle of the car, yet still problems.

I was tracking the car so much that at some events, I couldn't run unless it was in beginner classes. That sucked. So, I got rid of it for putting a real roll bar set-up wasn't realistic for it was impossible to do so without completely disabling the convertible feature which made it BS.

I stripped the car of race equipment, returned it to stock, and got rid of it. I acquired a salvaged Lemans Sunsets Coupe and am building a new track car very similar to 350NV's Project Double Down Car, just with the interior.

Good luck.

M

 

the Z chassis is very stiff to start with. dual firewall and the tall area behind the seat plus both front and rear strut bars make for a very strong chassis. also having the entire drivetrain front and rear being their own drop in units, distribute the loads over many points.
true roadsters are not the best for tracking unless you have a full cage or many levels of chassis stiffening. the coupes are much more rigid.
obviously at a certain point to much power will twist stuff, but as said earlier, you would have to hook it up before enough pressure is generated to even have a problem. by the time you were running that much power competitively, you would be required to have a full cage anyways.

 

What up Scott?

Going to Laguna Seca with Ed and MBs cars for another magazine photoshoot Monday and Tuesday.

M

 

the answer to so many "why is the z so heavy?"

 

hey michael, you guys have all the fun!!!! which magazine is it for?

 

Mraturbo, OverZealous1

I have an '04 roadster. Last dyno tune was 502 rwhp (uncorrected) @ 10PSI on 93 octane. Daily driving I run either 5 or 7.5 PSI depending on the weather and to save on wear-n-tear.

I am already running 12's and have been told that to meet NHRA guidelines I need a roll bar NOW, and very soon will need a cage. I am looking into having a bolt in cage made (when racing the top will be up and the cage installed) I agree it is not possible to drop the top with the cage installed but as it will be removable we 'Should' be able to get something to work.

I will also be looking into an underbody chassis brace this summer.

The reason being that I will soon be putting in a new built engine and expect to be running 20+ PSI for the 1/4.

Thanks for the thoughts,
--B