mlcrycc

When you went to Forced Induction, did you note the necessity to let your car warm up quite a bit better than before? Anyone have an issue with leaving on a very cold start, and have issues with feeling like you were loading up on fuel?????

Thx,
Mike

Stkjock

None for me, are you running the Vortech tune? mine was custom tunned, the Vortech tune is known to be pig rich

mlcrycc

No, running the Brenspeed tune....

After it is up to operating temp, it is killer.......

forper1

I let all my car to warm for 30-60 seconds before driving. And get to full temp before getting on it. I did it once, started and hammered on it and I got oil blow by(white smoke)

mygt500

I did but I think it was the 60lb injectors that needed some "break in" -Also the tuner left the car pig rich and the A/F ratio at WOT was 10.9....too rich for the Whipple! I now have the car with an A/F ratio across the board of 11.3-11.5 and gained 10 RWHP on 19 degrees of timing (max) and this is the less efficient Gen 1 S/C. My bet is your tune is a bit rich (esp at start up). I read something stating that we have a closed loop system when cold and open loop system when warm. The closed loop system usually opens shortly after warm up (how long I have no idea). Now I maybe wrong in stating this but if I was rich when the car was warm then I bet it is safe to say that the closed loop system is even richer until warm and when open it is a variable system to regulate the operation of the motor smoothly.
So based off this I got the car back on the dyno and gained HP and fine tuned the A/F ratio and the "start up" issues were resolved!

I have bigger injectors and we (tuner and I) factored in the fact that when cold they are "quirky" and way too rich (along with the closed loop start up)....over time (different for everyone) it seems they are not as quirky and I can start the car and go (maybe 1 or 2 mins later-never WOT until at operating temp for me). Next set of injectors I will get flow tested and matched !!!! (less issues then)

Hope it helps and do you have gauges? can you datalog? Would help to see and save and send to Brenspeed. Oh and I never threw any codes....

HaneyMotorsport.Com

Mike this may or may not help...... Re-clock the MAF housing so the sensor is more at a 90 / horizontal position.

Casey

67fire

I start mine and go. Wait until it is warm, before going over 3,500 rpm.
It gives the bearings some time to get ready.

Eric

modaddict

Sometimes - the fuel trims are too high or too low for the car when cold.

once quick fix is to set your rpm idle a little higher and the car will 'clean out' quicker when cold.

The quickest fix When the car is cold is to just try holding the rpm's at around 2200-2500 for a minute and then you should be good to go.

mlcrycc

Guys,

Thanks for all this input. This is some of the best info I have gotten thus far....When bone cold, and if I start out, to me it feels as though the car is....flooded....as a matter of fact, I have had it actually backfire a couple of times, after which it does seem to "clear out" . Modaddict, you hit the nail right on the head with that term, as that is exactly what it feels like. If I let the car just sit and idle until operating temp is met, then it runs like a fricken raped ape from the git go......
GT500...Excellent info, and yes, you too have hit the nail on the head as far as the impression of the car when cold...
Casey,
Thanks for dropping in as well. The Vortech instructions clearly specify clocking to the 10 o clock position. Seth had me re-clock to the 7 o clock position. Perhaps I should try the 9 o clock as well....
Now, let's talk fuel delivery...I am using a KB BAP. Hard wired to on all the time, running full on rich.....Because I suspect this is a fuel issue, I asked the question if I could dial it back. I was told I could dial it back to 30 from 50, without risking lack of fuel. This morning I took it back to 40, but, I had already warmed the car. So, I should be able to tell after work if this made any impact.....
It just feels as though the car is loading up when cold, but killer when warm.....
Thanks again, you guys are giving excellent advice and suggestions...and it is appreciated.....

Mike

mygt500

This was exactly what mine did and modaddict's trick works for me too and I believe in time as long as no codes are thrown you will notice improvement in the cold start issues.