RedRyderTT

Outstanding. This is the type of feedback I was looking for. Hinson is releasing some coilovers soon, so I might wait for them.

I will post the build thread as she comes along, for now I'm hoarding parts until I have everything.

JETninja

I don't know if regular C5's have the same spring loaded center airdam as C5Z's, but if they do you need to brace it some how, its starts folding back at any much over 160mph.....

Piotrekzzz

I talked to a Lingenfelter guy on the forum one day. He told me that the one big mod the did was putting a balast in the trunk to make sure that the rear of the car stays on track. I only don't remember how heavy was it... 150-200lb probably. I've been only at 190 so far with stock suspenssion and no balast.

ysb02

Salt will tear the **** out of your car. Would only do it with a dedicated race vehicle.

Power, gearing, and everything in spec is the goal to hitting 200 in a c5. It doesn't take aero, winglets or body mods.

Piotrekzzz

It was 300 lb. :-)

bill mcdonald

Gearing?

Piotrekzzz

I don't know, but probably they change it. If you don't change the rev limiter of the engine the 5th gear brings you to around 190 mph and to accelerate at the 6th gear you would need tonns of torque. I am not sure whether it was the gear or the axle.

ysb02

5th gear = 192.6MPH coupe (m6)
5th gear = 169.7MPH z06 (m12)

Supposely 6th isn't safe to pull even (gear too small) if it wasn't so high.

Best bet is to use the 5th/6th from the ZR1. It's closer ratio and a lower 6th. 5th taps out At 185mph but 6th will pull up to 224MPH and is actually usable.

Piotrekzzz

Exactly :-). As he wants to go to 200 mph he must have made big mods to the engine. If he's got forged pistons he could also increase the maximum revs of the engine. 6450 rpm would bring him to 200 mph, 7000 rpm to 218 mph.

Quickshift_C5

5th gear in the C5 ZO6 will do well over 170mph, it will be in the 180-185mph range. My C5Z with original diff/trans does 164mph in 5th at all the 1/2 mile events and it has a long way to go before redline.

Rkreigh

don't try going this fast without getting fresh tires rated for that level of sustained speed.

also having the suspension "soft" won't serve you well at that speed as down force is starting to push the car down and if you lower it (which you should, it helps) you need a stiff enough spring to retain suspension travel.

I really like the coil overs as you can properly stance the car to get the front end lower and keep the tail up

putting weight in the tail might help but make sure you have it very securely buttoned down.

the old LPE TT cars went well over 200 (223) at the track with stock body and suspension so the c5 will do fine with some relatively minimal mods.

I'd like to see a bit better brakes for wowing down from 200 too. I went with the wilwood superlite 6 pistons up front 14" rotors (cheap) but stoptech seems to be a bit better.

Good luck, make sure you have PLENTY of shut down space.

jbsblownc5

Hey, sorry I did not see this right away, let me know if you have any specific questions for me, that may not have been answered already...

neverstop

I haven't made a full 200mph pass but went 179mph in 1/2 mile on my old setup with honestly not a ton of shutdown space at the event and was fine on c6 z51 brakes with aggressive hawk pads and new slotted rotors, high temp fluid and nothing special for tires, just nt05r on the back and some toyo proxes on the front. Just have to get on the brakes fairly hard and smooth right away, and it's not like you have to come to full stop because at the end you can usually take that corner at 40-50mph since wide corner. I just allow lots of time between runs for brakes to cool and really not an issue at all for me at least.

first few events I was just on stock c6 z51 suspension lowered and aligned and that helped, then moved to LG coilovers and honestly did not really notice much of a difference like I had hoped for straight line at least and the traction honestly may have actually gotten worse as i now have to run the LGs at nearly full stiff or i get wheel hop

I would make sure you get good alignment of course at high end shop and get a neck brace and some harnesses. most events have pretty high tech for that speed too so I'd read that but most places require arm restraints, steel lugs, etc

my car became far more stable once lowered a good bit and the trackspec hood vent helped also.

lots of guys have done this over and over though so the recipe is out there

Piotrekzzz

Well, I did 190mph on the highway in a stock C5 with only engine mods. No suspenssion, no tires changed, nothing. It was pretty stable. The thing is that 200mph differs from 190mph more than eg. 110mph differs from 100mph.
Jbsblownc5 has done a nice ride much over 200, so his info should be more accurate.

neverstop

well take whatever advice you want but the point is that a big brake kit is not necessarily required if you have good pads and fluid with fresh parts to do a fast standing mile at an event with plenty of runway. If you want to do it than it certainly is good to do but imo not required based on my own experiences. The event I was at had less than 1/2 mile run off to slowdown which is not much at all for those speeds and less than all of the standing mile events I've seen and I had zero issues.

rick in his c5 below i believe has stock brakes too and has gone faster than joel in the standing mile. he has parachute but also has cage, subwoofers, etc and so not lightweight and is running very skinny tires with shields on them so rotor temps are probably even higher than if he had them open.

the point is there are people doing 200mph in standing mile with stock brakes who are fine.

StuntHeavy

It's apparent the tr6060 is far superior to the t56, but for the sole sake of achieving 200mph out of a t56-equipped car, is there anything stopping people from using a different diff ratio to achieve this in 5th with a t56?

ysb02

Nope a 3.15 or maybe a 2.93 should put 5th gear into the 200+ mph range. I don't have my spreadsheet handy. Also raising the rev limit can give you a bit of wiggle.

Fastbird

I think you may be the guy who a shop was talking to me about a while back. I was at Hoosier Performance Engineering and they were talking about your C5 going 202 and we were comparing your car to mine (mine did 202 also) in terms of modifications and setup. Your car helped along by an STS kit? I'm pretty sure it's you they were talking about.

jbsblownc5

I've got a built T56, with the lower 5th and 6th G-force gears. I used to run 373s in my quaife diff, but last time we build it, I went with a 30 spline tranny shaft and 30 spline 342 diff...

trayack

My car is the sister car to John's personal yellow TT coupe, and yes...it has indeed been that fast with its previous drivetrain combo with the first owner. Stock body, no aero mods whatsoever.

- Travis