88BlackZ-51

I thought I would start a new thread:

I have never been 200 mph in a C4, but I have gone 195 mph in a C4 ZR1 (stroker) as a passenger. I have also been 200 mph in a Viper TT, and a C5 TT. I have to admit it was something else, and I have always wondered if my C4 would be capable of such a speed, and just how long it would take to get there (more important). I remember the first time going 200 mph years ago (I was the passenger), and after we slowed down, and got out of the car to do a walk around, the driver states "you have just experienced life", "you have just went 200mph". I started to think that not many ppl have ever experienced this.

That airport strip has lone been shutdown for such events, and I would have to travel states side to try such an event. But what would it take for my car to do 200 mph? (550chp/530tq, 421sbc).

Well my build is getting close to the end. A little more time, and she will be starting up.

Let's say it rev's to 6300 rpm's, and it's equipped with a ZF6, and still has the factory D44 (3.07's) from the general from 1988. Using the gear calculator, this seems like the perfect gear for top speed compared to the 3.45's that I recently purchased.

Tire 315/30/18 "W" speed rated to 168mph.


3.45's

5th gear 6000 rpms =176mph
5th gear 6100 rpms= 178mph
5th gear 6200 rpms= 181mph
5th gear 6300 rpms= 184mph

3.33's

5th gear 6000 rpms= 182mph
5th gear 6100 rpms= 185mph
5th gear 6200 rpms= 188mph
5th gear 6300 rpms= 191mph (getting closer!)

3.07's

5th gear 6000 rpms= 197mph
5th gear 6100 rpms= 201mph
5th gear 6200 rpms= 204mph
5th gear 6300 rpms= 207mph

I am sure I wouldnt have enough power to get to 207mph, but kinda interesting, but 6100 rpms is do-able.

With a 3.73 gear you would have to rev to 7400 rpm's in 5th to reach 200 mph. Hence why the LT5's have such a good top speed with there long legs.


Who here has gone over 185 mph in the C4's, and what mods?

DDSLT5

car5car

I was driving 80 MPH once! 200 MPH feels the same, right?

65Z01

200mph......I'm still working on the cahunas to try 150mph...

The original Chevy sales lit for early C4s states that top speed is in excess of 150mph. Consider that wind resistance goes as the cube of velocity and original CHP one could come with an estimate of power needed.

How much power were those rides mentioned making and what was the gearing to get them up there??

If your new build makes close to 500chp and will hit 600rpm, I think you have a good shot at 200mph with those 3.07s.

JrRifleCoach

Your gonna need at least 550 HP in a C4.

88BlackZ-51

I'll have the ponies.

black_89_vette

Get it on film Rick. I have asked that question years back and was told around 580 hp was required.

Would you tape up the seals in the hood? Didn't they tape up the Sledgehammer a bit?

j-vette

tequilaboy

For comparison, C&D went 212 mph in an LPE prepared 95 coupe at 7,000 rpm with 3.33 gears

The 427 engine made 603 hp at 6,200 rpm, so it was running quite a bit past its peak at 7k to achieve 212 mph.

383vett

My 08Z06 with factory 505 hp has a top speed rating of 198. With bolt ons (headers, intake, exhaust, tune it now puts out 487rwhp compared to the stock 450rwhp. I would think the extra 37hp would get me 2mph. Anyone have a deserted airstrip available?

88BlackZ-51

That's great that your stock 427 can do 198 mph (stock).

But this is about C4's. I am hoping mine will make 475rwhp/450rwtq, but who knows.....

5abivt

lower a c6z .5 inches and you can hit 200.

383vett

Ok, ok, you are right. Back to C4s. My 84 runs mid 10s at 126. Now I have to find gears along with the airstrip.

kawijames

Honestly it's going to come to gearing and space. There was a member here that passed 200 with an LT and a big shot of juice at maxton.

Personally I'm going the easy route on my 87.

500rwhp with 2.59s,built 4l65E, and progressive shot should give me more than enough to pummel 200 mph. Granted I'm staying auto with the trans programmed to upshift at wot. But it's been done a few times, C4's in the 200's that is.

88BlackZ-51

Thanks. As you can see this can get off topic very quickly with 8000rpm(Mikey) posting.....

I am hoping for that same trap speed of 126.

88BlackZ-51

Are you going with a stroker LSx? I wouldnt say that's the easy route. I looked into an LSx instead of the SBC1, and there was alot of work to do it that way. Anyway you slice it, 200 isnt easy.

I am not positive, but I would think I would need at least 2 miles.

Goodluck and let us know how you make out!

5abivt

Hey I wasn't the one who brought c6 into this ! was merely stating it can take something very minor to pick up 2 mph at those speeds.

I went 235 in a 95 ZR1 making about 745 hp @ 8400 rpm. It was amazing !

kawijames

Technically its an LQ4, For now. my other half is pushing me to bore and stroke to 418.

But with p&p 243's,62cc chamber it brings my compression from 9.46:1 to 11.xx:1(depending on head gasket thickness. Cam is 23x/24x 64x/60x. (Not posting exact specs, custom grind) but you get the picture.

This build has changed directions a few times now but hopefully she'll make her debut at gateway intl in August.

We went LSx for a few reasons,power,flexibility (drag, maxton and silver states),and DD ability.

cv67

Dont know that youll get 500 at the tire on that. Should be a lot of fun though.

Rick get the dust off those tools, get wrenching and find out.

surfer92

There was a thread about going 200 mph and had a video, think it was in general section and he described everything he did to get to 200.