Trans questions for Hellno.

[Marc W]

David.... tell us about leaving in second gear. Super high hp cars (like yours 🙄) are commonly needing to pull power to get off the line. The issue being too much gearing to get it to hook on anything less than a extreme prep surface. One answer to that is what Zdung is doing. Keep the power and decrease the gearing by leaving in second gear. What are the considerations with doing this? How does that impact the trans and are there converter changes necessary to make it work? Thank you... 😘

 

[zhc]

🤔

 

[Marc W]

🤔

Haha. Yeah Z you started this. 😂

 

[Hellcatcfp]

Following.

 

[fubar569]

In for boobs.

 

[zhc]

Haha. Yeah Z you started this. 😂

Here’s one of many kickers, I’m using a 2nd hand modified stock converter done 2-3 years ago by Paramount. If you could go back in time and imagine where converters were at back then for this platform, all you had were opinions on what should you do. Do I want a tighter converter? A looser converter? Harder hitting or soft? Billet options weren’t even a mention back. Are things any different today in this space?

 

[Marc W]

Here’s one of many kickers, I’m using a 2nd hand modified stock converter done 2-3 years ago by Paramount. If you could go back in time and imagine where converters were at back then for this platform, all you had were opinions on what should you do. Do I want a tighter converter? A looser converter? Harder hitting or soft? Billet options weren’t even a mention back. Are things any different today in this space?

The space in my head is limited so I went straight to the simplest answer.... T-400 with a custom converter that was built using the long list of specs that Coan Engineering asked for. Done! I’m a genius 😂

 

[zhc]

The space in my head is limited so I went straight to the simplest answer.... T-400 with a custom converter that was built using the long list of specs that Coan Engineering asked for. Done! I’m a genius 😂

Yup, and you also get decades of vendor and race experience to back up and guide those decisions. Good move Marc!

 

[DMNkilr]

Pretty much the same as Marc, only with AJ, Rossler, and Pro-Torque. 2.10 first gear with a high stall converter has been great so far. Still an IRS rear (G-Force).

 

[hellno]

I believe the 2nd gear start is easier on the drive train and with a good stall and nitrous off the line should settle the car down compared to launching in first gear where the gear ratio is so aggressive , I believe @zhc runs a2.62 (correct me if I’m wrong )
I wonder if a 3.09 might perform better, at my power I don’t believe 2nd gear starts will help but where y’all guys are it’s different @Marc W i think your change to the 400 was a wise decision because of durability,but @zhc he is doing amazing things with the charger and has changed the game ,2nd gear starts will definitely improve traction going from a 4.71 to a3.14 ratio on the launch is a lot ,also the 2nd to 3rd shift is much smoother transaction then 1st to 2nd and tends to unsettle the car

 

[Marc W]

If Z checks back in he can confirm but the list of info that was posted on FB said he is now running the 3.09 with the taller 30” tire. It would be interesting to see how the 3.14 second gear in the hp90 and a 3.09 rear compares to my 2.48 first gear with the 3.40 rear and the same 30” tire. Looks like it might be close.

 

[hellno]

If Z checks back in he can confirm but the list of info that was posted on FB said he is now running the 3.09 with the taller 30” tire. It would be interesting to see how that combination off the 3.14 second gear with the hp90 compares With a 3.09 rear to my 2.48 first gear with the 3.40 rear and the same 30” tire. Looks like it might be close.

👍

 

[DMNkilr]

If Z checks back in he can confirm but the list of info that was posted on FB said he is now running the 3.09 with the taller 30” tire. It would be interesting to see how the 3.14 second gear in the hp90 and a 3.09 rear compares to my 2.48 first gear with the 3.40 rear and the same 30” tire. Looks like it might be close.

If @zhc is running the 2.62 and the same tire as you are, using the second gear start there's only about a 2.5% difference in the final drive ratios between your 2 cars. If he's running the 3.09 he goes from 2.5% less than yours to 13% greater. Mine is about 12% less than yours , but is somewhat offset by my running a shorter tire

 

[zhc]

I did indeed switched to a 3.09 gear and 315 pro tire combo. I've been testing my theory behind launching in 2nd gear for a couple months now and it showed promise. It has been easier to tune for because it slowed everything down and was more consistent. I could still blow the tires off launching in 2nd but I think that had more to do with sub-optimal or improper shock tuning then anything else. In practice, I felt like I needed more gear to over come the following disadvantages.

1) Can't hit the tire as hard launching in 2nd off the foot brake as you can in 1st. The mere moments the engine spends before the converter reaches its flash stall point at the power you're pushing is what I'm talking about. I was hoping to get some of that "hit" back by the gear switch (and it did help)

2) After you lose out on the magical tq multiplication effect of the converter, that mid range to top range going up to the 2-3 shift was a little flat even with 100% nitrous ramped in by that point on my setup. I felt like I could put more mechincal tq to the ground so another reason why I wanted to try 3.09.

3) If you tune the 1-2 shift a certain way, you can get somewhat of a slingshot effect from it which can give a slightly momentary bump in acceleration. Launching in 2nd gear, you lose that opportunity.

The tire change was because most of the classes I've been in do not have a tire size restriction. Why not go bigger like so many others have? Joining the dark side in that regard. It does feel dirty, but I like it.

Side note, it's not just the gear and tire change that helped me hit that 1.22 60'. There were a combination of shock related adjustments and changes that I had been working on since my last trip out a couple months ago. I'll be able to validate when I try all this on a 275 pro tire so stay tuned for that.

 

[zhc]

I believe the 2nd gear start is easier on the drive train and with a good stall and nitrous off the line should settle the car down compared to launching in first gear where the gear ratio is so aggressive , I believe @zhc runs a2.62 (correct me if I’m wrong )
I wonder if a 3.09 might perform better, at my power I don’t believe 2nd gear starts will help but where y’all guys are it’s different @Marc W i think your change to the 400 was a wise decision because of durability,but @zhc he is doing amazing things with the charger and has changed the game ,2nd gear starts will definitely improve traction going from a 4.71 to a3.14 ratio on the launch is a lot ,also the 2nd to 3rd shift is much smoother transaction then 1st to 2nd and tends to unsettle the car

From the driver seat, it certainly feels like it's easier on the car. Just ultra smooth compared to most of my more aggressive 1st gear launch attempts. One big downside though is, when the tire lets go, I can't recover as quickly as I do in 1st so it basically kills my chances of winning a race when it breaks loose.

 

[DMNkilr]

I did indeed switched to a 3.09 gear and 315 pro tire combo. I've been testing my theory behind launching in 2nd gear for a couple months now and it showed promise. It has been easier to tune for because it slowed everything down and was more consistent. I could still blow the tires off launching in 2nd but I think that had more to do with sub-optimal or improper shock tuning then anything else. In practice, I felt like I needed more gear to over come the following disadvantages.

1) Can't hit the tire as hard launching in 2nd off the foot brake as you can in 1st. The mere moments the engine spends before the converter reaches its flash stall point at the power you're pushing is what I'm talking about. I was hoping to get some of that "hit" back by the gear switch (and it did help)

2) After you lose out on the magical tq multiplication effect of the converter, that mid range to top range going up to the 2-3 shift was a little flat even with 100% nitrous ramped in by that point on my setup. I felt like I could put more mechincal tq to the ground so another reason why I wanted to try 3.09.

3) If you tune the 1-2 shift a certain way, you can get somewhat of a slingshot effect from it which can give a slightly momentary bump in acceleration. Launching in 2nd gear, you lose that opportunity.

The tire change was because most of the classes I've been in do not have a tire size restriction. Why not go bigger like so many others have? Joining the dark side in that regard. It does feel dirty, but I like it.

Side note, it's not just the gear and tire change that helped me hit that 1.22 60'. There were a combination of shock related adjustments and changes that I had been working on since my last trip out a couple months ago. I'll be able to validate when I try all this on a 275 pro tire so stay tuned for that.

Thanks for your posts, a lot of good information there and a few new things to think about

 

[Marc W]

Thanks for sharing! The one thing I noticed after switching to the 400 is exactly what you’re saying about the launch being smooth compared to the A8 first gear. I ran a 1.26 best and it’s just a long smooth push from behind. All this is good info for anybody making too much power for the track. Give it a try!

 

[cole3986]

I launched a few times in 2nd, cat run slower, so I stopped doing it. Is Z saying is has a 60 foot of 1.22 launching in 2nd in a A8? I am hearing this correctly?

 

[hellno]

Cole with nitrous and enough power you can
At our level wexx xx will run slower

 

[Linda's Hell Cat]

Here’s one of many kickers, I’m using a 2nd hand modified stock converter done 2-3 years ago by Paramount. If you could go back in time and imagine where converters were at back then for this platform, all you had were opinions on what should you do. Do I want a tighter converter? A looser converter? Harder hitting or soft? Billet options weren’t even a mention back. Are things any different today in this space?

I will NEVER buy anything from Paramount
He is a Thief!
Linda