LeMansBlue04

Took my C5 to Hallsville last weekend. It was my first time to run with my ET streets, line lock and all my power producing mods.

My 60' times were not good. Most were between 1.910 and 1.950, I did have one that was just below 1.900 in other words the very, very high 1.8's. I was running 16 lbs of pressure in the tires and my buddies who watched carefully say I was not spinning off the line.

I was simply working the lights at idle and then hitting the throttle at the proper time. I have a Yank 2800 stall converter from LPE. My HP numbers are 400 RWHP and 351 RWTQ. The gears are 3.73 with a hardened shaft.

How should I be launching this car?

Based on a test I did on the street in the past I was under the false impression that I could only brake and hold it up to around 2200 RPM. I tried it yesterday on a parking lot and I could hold it all the way up to 2600 RPM with the brakes in competition mode. At my power levels can I expect to launch the car this way or might it bog down?

How do the rest of you think I should launch and what have you experienced or seen with similar setups? I don't want a higher stall, I had an SS3800 and hated it on the street, never used it at the track.

My best time of the day was 12.202 at 118MPH

WALLstAL

I think your problem is with the T/C. I have the S/T-3500 with 2.5 STR with a best 60' of 1.66. I had a PT- 2400 for a couple of years, that didn't get the job done. I power brake up to about 2600 rpms and hit the gas.

What is your STR on that Ling/Yank 2800 Converter?? I have E/T Street that I lower the pressure to 16 PSI.

'06 Quicksilver Z06

Take it up to 2500-2600 RPM when its trying to break through the brakes and launch it.

LeMansBlue04

What is the STR? Thats a good question. LPE has Yank build it specifically for them so it's not an exact copy of anything Yank makes.

Its built with a 10.5” heavy duty carbon ceramic clutch, a billet front cover, furnace brazed fins, anti balloon plates, oversize roller clutches, high capacity stator and an epoxy paint finish. It weighs only 36 lbs.

Those specs don't match any of the standard units Yank makes in a 2800 stall. However it doesn't matter what the specs are because I am not going to change it. As I said I have been the high stall route and I did not like it on the street.

'06 Quicksilver Z06

The big thing here is those big 3000+ stalls. Not for me either. Since racing is only about 10% of what I use the car for no need for a very high stall. Gets old fast in normal driving.

You may have to accept that you have reached the extent to which your car will perform however, if you are unwilling to go with a higher stall and essentially turn it into an every weekend racer.

C5pilot

Your 60' seems high with your setup, IMO. Let's see... You're putting down 400 RWHP through 3.73 gears and ET Streets and you're not spinning. Your TC is what, about twice the stock stall rating??? If you're not spinning and you're not moving, where the heck is all that power going? Start loading your converter at least into the teens and see if you can get that number down. I think you're bogging.

Otherwise, I'd say you either have tranny problems, the wrong converter from day one or you're NOT getting 400RWHP like you think you are. Again, just my .02 (at a discounted rate)

tabbruzz

So here is a question....I also have an aftermarket converter. My problem is that I cannot get the car to hook with drag radials. I've tried different burnout techniques, lauching from idle, launching at about 1200rpms, babying it out of the whole, which will not produce any new bests. So with a car that stalls up to 3100 will I spin more or less if I bring the rpms up to about 2300? Any opinions...Mods in sig for the 99.

Fastbasser

With 400 rwhp, I would bet your convertor is to small for your cam. (takes a big cam for that much GP in an A4)

With my new convertor, I pulled high 1.60s with 3.42s and Nittos.. With my old convertor, the car felt like it had to get "on the cam" before it took off. Hense, 1.80-1.90 60' times.

I would bet I could get 1.50s with ET streets..

JMHO

LeMansBlue04

I think you all have some good points here. As to where is all that power going? As I said I was coming off the line at idle and just hitting the gas. I never tried to power brake it at the track. With the dyno numbers I have I wonder if the combination could launch it at say a 2500 RPM launch?

I am also wondering how the car would react to a similar stall speed but with a STR of about 3 to 1? I wonder what the effect would be further down the track.

WALLstAL

High stall converters with high STR of 2.5 and above are very streetable and are not lose at all. Especially when you reprogram the computer and set the out of gear idle to approx. 900 rpms and in gear to approx. 850 rpms when you change cams. If you could drive my car, you would realize that, it feel like normal (stock)to me.

LeMansBlue04

Well, I wish I could drive your car. It would be interesting to see how it compares to the SS3800 I used to have which had a STR of 2.55

Compared to my current 2800 the SS3800 was very lose. Additionally, the exhaust note resulting from the higher RPM made it very unpleasant to drive on city streets.

I think this is kind of like picking a color when you buy your car, it's a matter of your wants, desires and personal taste. I am glad that you are happy with your converter but it's my bet that I would not be.

Some people like chocolate chip cookies, others like oatmeal/raisin. It's just a matter of taste.

But you are no doubt right about one thing. A 3500 stall would give me a much better launch. I just can't live with it on the street.

C5JONNY

sounds like you really should have gotten a manual

LeMansBlue04

Well not really, every thing is a tradeoff, the M6 has a launch advantage and 4 gears going down the track with a tight ratio.

However, if you bracket race, getting an M6 car to run consistantly is just impossible. That's why I have an A4.

LeMansBlue04

We started talking about converters and kind of got away from what I was asking about. Have any of you used or seen someone use a Yank 2800 to launch a Coupe without bogging it down?

Allthrottleandsomebottle

I see no mention of tire pressure..........VERY IMPORTANT!
I run 19psi hot in the 97', 3500 stall & 3.73 gear
I run 18psi hot in the 00' vert, 3000 stall @ 3.42 gear
Not a good track day for DRs with the 00' coupe yet...stock TC & 3.15 gear
I load the drive train to 1100 rpms.......then leave off idle.
Below are my times...........works good for me

Y2K MY Coupe, W/NITTO 555 275/40/17 STREET TIRES @ RDW 11/09/03
60'=1.91, 1/8=8.05 @89.32mph
1/4=12.47@111.91mph (3,470 lbs. race ready with me in it)

1997 Artic White C5 3/14/04 at RDW on BFG 345/30/18 drs
60'=1.52, 1/8=6.99@98.81, 1/4=10.97@122.45mph (3,680 lbs. race ready)

Y2K MY Vert 11/14/04 at RDW of BFG 275/35/18 drs
60'=1.72, 1/8=7.89@86.52, 1/4=12.49@109.65
(tuning issue to be fixed for next year.......11s coming )

vstella

I feel your frustration..Been There and Done that my friend

After many combos..here's what works for me..

1- E.T streets at 12lbs. psi skinnies at 40 lbs.
2- 7-9 sec. burnout at 5000 rpms with line loc
3- stage at the light and bring up the rpms to 1400 and flash the T/C on the third yellow ..Don't let up until you cross the traps..

Check out my videos on my CF homepage link below..

shurite44

IMQUIK

I got a 1.862 on Michelin Pilot Sports launching off idle with 3.73's & SS-3600.

jpee

Not true..

An auto with good tired & converter has a launch advantage....the 6M will usually have a higher trap speed, but the auto wull have better ET.. & ET is what wins races... (thats id both cars have the same HP motors)..

REDGAR

I ran a Pro Torque 2800 for a while and don't remember bogging it with drag radials. ET Streets maybe but not drag radials.

As for the 6 speed being a good bracket car, it really depends on the driver and their focus. Bill Martinson (BILLY2K) finished second in points a few years ago in our Corvette Challenge and missed the championship by one point. We have had other 6 speed drivers dow well and this year we have two manually shifted cars, a Z06 and a C2 with a 4 speed, in our Top 10 out of 117 Corvettes.

So difficult maybe, impossible no.