7secondsquarter

See the attached site. While it is mainly about a very high horsepower C5, I have added a blog on a 1994 C4 Coupe that my brother and I have purchased. Based on recommendations from forum members we have added a D44/3.45 gear, a 3600 stall converter, a line loc, some drag radials, a tune from PCM for less and are having a ball with it at Englishtown.

You can find my comments in the blog page. Please feel free to comment and I will be providing updates as we continue to make improvements and gain experience with the car.

www.dragvette.net

engle1147

site good luck with the season.


IBTL

Calderone

http://www.dragvette.net/1/post/2011...-to-edit1.html
You should make a complete new site for the C4
what's the engine mods ?

dan_t

From the blog -

Calderone

Yes i read it but it surprises me that no other mods has been made ...specially to the engine its like modifyn backwards , but i would like to know more

davenbocafl

those changes are great but what about hp

dizwiz24

It would be nice if you could create a site about this c4 that is beating that high hp c5.

Happy you are enjoying the c4

7secondsquarter

Thanks for the comments Guys. Maybe a separate page for the C4.

We wanted to take it slow. My brother and I came into a small amount of funds from inheritance that was used to buy the car plus had about $4K to play with. The car has been very well maintained but still has over 120K miles on it so I worry about the motor.

We decided on these mods just to get the car going down the track and consistent. Next up will be a set of headers/exhaust. Then maybe beef up the transimssion. And after that heads/cam or if the C5 sells look at a roll bar and maybe either a turbo kit (STS) or Supercharging (Carroll's).

For this year my brother will pretty much run it as is for bracket racing and I have signed up to run the 8.90 GM EFI class introduced at Englishtown with the C5. The headers will come over next winter. Any opinions on the ARH vs the stainless steel headers?

7secondsquarter

One other thing that I have been seeing. The have been posts about a stock C4 running low 13's and even very high 12s? Once we have the hiccup fixed on the 2-3 shift we should be right around 13.5 with a 1.75 60'. Could it be that this motor is a bit tired? We still need to do a few thigns like run it on 1/4 tank of gas, take the spare tire out and some other diet items but I am thinking that this would not be enough to get all the way down into 13.1 to 12.99 range.

STEVEN13

Hi,

My 92 6 speed is pretty much stock (more set up for road racing) over 100K miles. It has a tune, 1.6 rockers, and tri-y long tube headers. Make 289 RWHP and ran a best of 13.02 106MPH 1.89 60'ft. this past November at Island Dragway.

Regards,
Steve

7secondsquarter

Thanks Steve.

Pretty Stout given what you have done. Who did the tune? I am finding it hard to find a shop that wants to tune an LT1 vs LS platforms.
My tune is through PCM for Less. No complaints there. I've heard that headers and rockers will pick up some HP. Our 60' is 1.75 so I am thinking we should be able to get into the very high 12's when we do the headers.

Kubs

My L98 with headers and a ZZ4 cam ran 13.4 with street tires and a very bad launch. The car is set up for roadracing and that was my first and only time I have ever been on a strip so there is room for improvement. I would think high 12s are possible for a LT1 on drag radials.

STEVEN13

PCM For Less did my tune also. I forgot to add that I also have underdriven puleys (which was done to slow the power steering pump on a road course). Your 60' is real strong!

FYI before the headers and other stuff mentioned it made 266 RWHP.

Regards,
Steve

7secondsquarter

Well went to Englishtown on Saturday. Ist three runs were 13.62, 13.63, 13.64 so I am thinking that the car is running really well.

Then the car dropped to a 13.77, 13.90 and 13.91 with the 60" dropping from 1.75 to 1.85. Won a round due to my opponenet red lighting but then dialed a 13.91 and cut a .070 light only to run a 13.82 and break out.

I am thinking it is the transmission starting to slip but after talking to Tommy at Anger Management he is not so sure. We are going to take a look at the fuel pump and the Cats to see if they are the root cause. I originally thought it might be the transmission because of the trouble we were having on the 2-3 shift. But with the car slowing off the line we are not sure that it is power related vs. transmission related.

Anybody with a C4 have similar problems? Tommy is going to take a look in a few weeks as he is swamped with work right now.

Thanks!

Alan

JackDidley

Run at least 1/2 tank of gas. At 1/4 and you have a good chance of the fuel pick up sucking air when the fuel sloshes to the back. I run a full tank just to get the weight over the wheels.

leesvet

everytime I hear someone mention "cats" I tend to remember my experience...sluggish, mushy and slow(er).
fuel? .. pressure test for possible filter issues. watch the way the gauge behaves..not only the pressure but how the needle moves. filters AND socks can be problematic on these things. These injectors seem to have a limited life expectancy as well. Thats such a cheap fix that you can spend $250 tomorrow and buy yourself .25 second I'd bet ! Call Jon. He'll probably bump you up a couple lbs/hr and diddle your pressure around a bit as I did. Better make that $350 to include an adjustable regulator.
There are plenty of ways to use "lunch money" to get to 12's in a C4...it happens all the time. The base platform is great and almost anything and everything makes it go faster.

Cats and how well they flow when lit up or not....great question. Certainly an aging cat flows less than a new one and as easy as old technology cats burnt themselves out from overheating, I can see one being a problem when confronted with hi rpm flow like this.

...and with only 120K on that car, I would'nt worry too much. These are so cut-n-dried simple that you can tell pretty much what kind of shape its in internally by the oil pressure and oil temp. Your eng temp could be a factor in the performance though...mine is nite & day different from 180 to 195. So much so that I avoid "competitive" situations if its 200 or more....Mines so much more crisp at 185.
Good luck with the season !

7secondsquarter

Thanks! Send you a PM.

7secondsquarter

Just ordered a set of Bosch injectors from Jon. Great guy who knows his stuff.

Can't wait to get these on the car!!

leesvet

I think you'll be happy...
This has to be the best way to spend "lunch money" and get REAL performance gains.

I installed mine that were a few lbs bigger because of enhancements to the motor, and then just had to play with the fuel pressure to find what worked well there...
With injectors that were bigger, I can now pull a spark plug and get a nice off-white color after high speed runs or sustained hi-rpm. Perfect.

Not to sound like a marketing scumbag thats trying to sell something, I've never heard ANYONE complain or say that they failed to see an improvement in the way their engine idled, responded and the smoothness with the BoschIII. They seem to make the motor feel new again...And Jon will walk you thru the build process and get you exactly what your motor needs with a little room to grow. Thats what I liked the most, he talks to his customers instead of just selling them what they want.

My ONLY complaint with the deal was the fact that my new injectors had the "F" word molded in the plastic tops.... Had to file that down so nobody would see...

Crowhater

if you have been following my build you will see I have been going to the track almost every week as i upgrade the car. I also noticed as the night went on my times started to fall off. At first I thought it was the track going away and the temp change but then I discoved something. When I first get to the track it is day light and when my times start going down it is night. At night I have my lights on as I drive around, not during the race. I am starting to think it is because my battery is not as charged up as it first was when I got to the track. I hooked my truck up to my car with jumper cables for 10-15 mins and made a pass, I dropped to a 8.3 from a 8.5. My normal pass without spraying is an 8.4. Tunning at the track is hard to do, I need to get my car on a dyno