I am building my 88 GTA I've welded in Detroit Speed subframe connectors and also installed their quadralink kit. The car Is a T-Top car. Originally, I was going to install a 10 point rollcage but upon further thinking about it I am not going to now. So now I'm trying to figure out how much engine I want but I think realistically I need to think of what the car can handle first.

 

There really is no set answer and no set power limit. What power are you thinking of and how will you drive the car? You'll find that a 4 point cage on top of SFC's help stabilize this platform when north of 500hp.

 

53 horsepower...

 

Ok I'm a dirt circle track guy myself so I don't know much about drag racing. The nhra says any car that can do an 11.35 in a quarter mile is required to have a rollbar. So what kind of hp does it take to get a third gen to run an 11.35 quarter? Just trying to use a little logic here. Maybe the factory gm, ford, and dodge should think about this some more. I know newer high hp cars don't have a rollcage or rollbar and can probably run a quarter faster than 11.35.

 

I think track legal cages are illegal on the street. People turn a blind eye towards the hobby builder but the OEMs could never get away with it.

 

A Cage is illegal on the street, most just turn a blind eye.

Reason being. Once you install a cage it becomes a safety hazard. Cages are designed to be used with helmets & 5/6pt harnesses. With a cage, you at least want to be using the 5/6pt harness to keep you in that seat and keep your head away from the cage.

A standard 3pt seat-belt allows an occupants body to move around too much, and your head WILL hit the cage. So you'll end up with massive head trauma in an accident where a 3pt belt combines with a cage.

The funny part is if you do have a cage, the 5/6pt harness is not a legal restraint, so you can still get a ticket for not wearing your 3pt seat belt even if you are strapped in like Neil Armstrong.



On Topic? It takes exactly 0hp to twist the body of a third gen when its stock. All the rigidity of a wet noodle. SFC's are a massive improvement. And get the car near modern levels of stiffness.

 

That was my reasoning exactly. I have owned, built and driven full on IMCA Stock cars. They have full rollcage with 4 door bars and a drverside door plate. The only factory pieces on the car was the g body frame rear control arms and lower front control arms. The body was the skin only bolted to the chassis to make it look like a 2004 Monte Carlo that I cut it from. I sat in a full containment race seat with a 5 point harness, race suit, helmet, and Hans device. I had a race fuel cell and a fire suppression system. I would drive upwards of 80 mph into a dirt corner along with several other drivers and I felt safe. I got into lots of wrecks some my fault some not. That is a race car. No passengers no interior it only races at a racetrack.

 

This. Perfect info here how it's a compromise. You'd think you're making the car safer but you arent. For the track, with a helmet, yes. But not for everyday.

 

Exactly. Do i want this car to be fun to drive? Yes! Do I want my wife to be able to lay her seat back and take a nap on a road trip? Yes! Would I like to rip around some cones and pretend I'm racing without damaging my car? Yes! Do I want to be able beat some kid in a mustang at a stoplight? Yes! So there you go. Where is that line? I checked on a ET/MPH to HP calculator and I came up with 400 HP will get you an 11.49 quarter mile is that about right? I guess that is the line for me.

 

That said, I do see the appeal and have even considered caging the car.

I HPDE the car, and most of the time I don't really realize just how damned fast the car is. I still think of it as that slow 14 second third gen I had in my 20's. But it makes nearly 500hp now and will solidly pull to 170mph in 4th gear like its the easiest thing in the world.

I really should cage it for my health. For as little as I drive the car, I can wear a 5pt harness. But if I wreck it at Road America or any other track where I'd be doing 130+ I'd be dead. A cage, Hans, and 5/6pt harness would save my life.

 

I can sell you mine it's brand new from Rhodes race cars.

 

Unfortunately money is a bit of a tight bit right now. Saving for a house.

The cage is easy. The install is the really important bit.

 

I plan on doing a 6 point roll car in the near future. a "Street roll bar" type configuration, not a cage.. Simple main hoop, two rear down bars, and two door bars which will be swing-outs/removable. Mostly to be legal for sub 11.49 passes, but also for structural rigidity. The plan is for S& W racecars to do the work, so it is absolutely done right.

?? Also a 5 point safety harness. --- I had no idea that it was not considered a legal seat belt ? thats news to me! wow

Kfactor, you will certainly need more than 400 hp to run faster than 11.49 if you have a 3rd gen with any "normal weight" to it. even a fully gutted stripped down 3rd gen would have to have more than 400 hp and the right gearing/powertrain to run sub 11.50's I would think.

 

Back to the OP's original question, I had Kenny Brown perimeter subframe connectors at somewhere between 550 - 600 Hp (427 LS stroker). It only took a couple months of spirited street driving for signs of cracks forming on the hard top, and every body panel was misaligned in some way. I installed inner subframe connectors and 6 point cage and nothing has moved since.

Kenny Brown was good stuff by comparison to what people normally buy, but Detroit Speed subframe connectors are the cats meow. I'd expect your car to be stiffer than mine was with just the perimeter subframe connectors.

 

IROCZman, Like I said I'm not a drag guy and I have no idea I just found that et calculator. So what kind of hp will get you into let's say 12-11.49 range?

 

no worries. Was just letting you know. There are a few good online calculators and some phone apps that can help you figure out hp and Gear ratios and car weight and how all that comes together for quarter mile and trap speed. Im an amateur just learning it myself now with my brand new engine setup and power train combination

with a good setup a 500-550 hp engine should get you into the 11s That’s right where I’m hoping to be with my 531 hp but my car is heavy and not geared for strictly 1/4 mile racing.

the DSE parts you have are well built and if setup correctly will be very beneficial for you and car rigidity. The car still will flex a bit but what you have now is a great starting point already

 

Well, depends if you want an 11 sec track car that runs 12's or 13's on the street, or an 11 sec street car that runs ???? at the track. At some point it becomes more of a matter of traction than Horsepower.

The new cars are so fast that it's ruining the hobby (in my opinion). Now you need 500 RWHP just to play. Even better to have more if you can do it.

The 3rd gen does have a weight advantage. I found that 550 Hp at crank (an honest 550 with accessories) could walk away from the ZL1, Hell Cat and the such.

 

New cars are built safer with crash zones and air bags. The nhra revsed rules to allow them to run 10’s without a cage because lets face it, alotof them with simple exhaust and tune changes with a drag radial are in the 10’s-11’s with basically stock motors. Thats impressive. 2018+ ss camaro will make 460’s whp with just bolt ons

400 hp can get you mid 11’s in a light well optimized car. More of a 3400-3500 lb street car that isnt optimized for drag racing like most of us? You’ll need more like 500. My 383 dynod 392 whp heat soaked on 10th pull. Went 11.47 at 119 mph

spohn subframes helped. But the roll bar helped alot more. It was a completely different feeling car

idk if i ever seen permanent twist of the chassis from power. With just the roll bar and subfames i ran close to 1400 hp and no obvious permanent twist lol but yes it was twisting hard on launch. But mostly body roll imo which can be fixed with anti roll bars and shocks