programing fast for quick spool up

[Alaskabuick]

I have heard several different opionons on getting quick spool up.

Rich to spool the turbo as it builds boost seems to be a fairly common opinion.

How does one program the fast for this? To you set your af ratio at a richer level in the cells the would represent when the car is spooling up?

Or should it be done with the TPS or MAP rate of change inrichment ?

Thanks

Dennis

 

[TurboTerry87gn]

Spool

I use map a/e up to a limit of 10 psi and also richen the appropriate cells up to about 15 psi, I find no need to help spool the turbo past 15 psi on my car. At that point there's enough exhaust energy to do the rest. I also remove timing so the egts go up. If you have a egt meter you can use this to see the resulsts. What your doing is burning part of the mixture as it is leaving the exhaust post this is the reason for the high egt's.

 

[scot w.]

Can anyone post some pic's of there screens? Like the base VE table and the Map a/e table for some examples? That way us that have spool issues can see what your talking about, it makes it easyier.. Scot w.

 

[TurboTerry87gn]

Correction

Let me correct my self...

MAP A/E fuel up to 150 kpa ~ 7 psi and VE table added fuel up to 10 psi. No need after that on my car. On a Supra I tuned I pull alot of timing first, add a little back at the same time richening the fuel, the initial timing pull out is to get things moving. Use you'r looging to look at the angle "how steep" the logged psi or kpa graph is. On road race cars that use manual transmissions they pull crazy amounts of timing out when the diver pushes in the clutch, the mixture actually explodes out of the exhaust port keeping the turbo spooled with no motor load. Think of it as using the exhaust as the combustion chamber.... poor valve seats and vales. I imagine they run iconel valves for that.

I would like to hear other peoples idea's as these are techinques I learned from others and reading.

 

[KevinB]

On my Accel Gen7, I can bring the car up on the transbrake, then add fuel in the cell that it gets stuck in. It's pretty easy to do, I'm sure Fast is about the same. Retarding the timing in those cells works also.

Edit: I usually do this in the ve table and the a/f table also.

 

[norbs]

Kevin, you could use the launch config screen, that allows you to add or subtract fuel and timing while only on the brake. But your idea will work on the fast system as it works on yours. If you retard the timing before you get into boost the car will be lazy while trying to spool and increase spool time. I add alot of timing just to get past the converter "hump" to get to about 1 psi with about 12.7 a/f and then retard the timing maybe to 7 psi then bring it back to normal timing after that. I haven;t datalogged the spool times yet, but in theory it should help. I will find out soon once the 76gts in on hopefully. Converter selection is the key, if its too tight there's no easy fix..

 

[TurboTerry87gn]

Spool

I going to give that a try. Not pulling the timing out untill a little after 99 kpa then start pulling it out after that up to about 10 psi. It makes since to get it over the "hump". Thanks. The supra was a standard trans and it worked for that. I'm allways open to new ideas...

Just curious what is your A/F ratio during spool. and at what point do you stop adding fuel for your application.

 

[norbs]

Each combo is different but, my car likes around 12.2 ~12.5 a/f around 4 psi and up, but with the 76 i may have to try something up to 13.0 or leaner. You will have to do a datalog to start automatic logging based on rpm maybe and you will have to stab the throttle the same speed each time. Then compare the boost rise over time, from lets say 0 to 10 psi. Try diffrernt a/f each time and timing and see if you can improve it. The problem is the turbo should be hot , because when cold your results will be not consistant, and a hot housiung spool much better than a cold one. Don't do it too many times as you will put alot of heat into the converter. You can turn down your fuel cut off to about 110 kpa, see how it goes. Please post your results, others would like to know what works in your case.

 

[norbs]

I did some more testing, pulling the timing does not work well to help spool up, bump it to 38+ and run it about 12.2 ish seems to work best on my set up.

 

[Dusty Bradford]

I did some more testing, pulling the timing does not work well to help spool up, bump it to 38+ and run it about 12.2 ish seems to work best on my set up.

+1. Pulling timing out of an auto car WILL NOT help. It needs more timing. Each car is different, some will spool at 12.2 to 12.5, others will like 13.0-13.5 down low.

 

[UR50SLO]

I bought a TH400 from a great guy in FL. It was in a stage2 car and it works fantastic. The converter is tight for my 109 block with lessCID and power than his. It's foot breaking at 2200 and rising slowly to 2800. I didn't have much ignition timing in it yet. I hope that will help the motor come up on RPM. Once I get that up to 3000rpm Boost comes up quick and it's fine.

If you guys are running 12-13 on spool up what's your AFR on WOT?
Great thread... This is exactly where I need help right now!!!!!!
Thanks for any help,
Scott~

 

[Dusty Bradford]

I bought a TH400 from a great guy in FL. It was in a stage2 car and it works fantastic. The converter is tight for my 109 block with lessCID and power than his. It's foot breaking at 2200 and rising slowly to 2800. I didn't have much ignition timing in it yet. I hope that will help the motor come up on RPM. Once I get that up to 3000rpm Boost comes up quick and it's fine.

If you guys are running 12-13 on spool up what's your AFR on WOT?
Great thread... This is exactly where I need help right now!!!!!!
Thanks for any help,
Scott~

Low timing makes the motor lazy on spool-up and does not work on auto cars. You need in the 36* range to help get the boost up.

AFR during spooling 12.5-13.0.

WOT will depend on the boost you make. You don't want 11.2 at 15# of boost.

 

[UR50SLO]

When It was my customers car (before I bought it as a rolling chassis) I had it steady at WOT 11.7AFR with 1-2% Correction through a pass. It seemed to like that alot. I'm starting safe with my setup and tuning from there. On my passes yesterday it was at 17psi and might have spiked at 18-19 during shift.

I put some more timing in it this morning so I'll try it again. I'll see if I can come up with any good or different results.

Several of my SY/Ty guy I talk with all the time run 12.0 AFR or leaner at WOT. I can't bring myself to go there.
Thanks for the advice!
Scott~