new pulley installed....got boost?

[cheftjpeck]

Had my smaller pulley installed today...and without changing my tune 100% yet (doing that tonight) I am definitely getting some more boost. I did not think I would notice going from the 3.8 to 3.6 but I do....the Saleen also seems to whine alot more than it did...I barely got into it yet as I still have the tune when it had the 3.8 pulley. Albeit Jim from JDM said that the tune for 3.8 is about the same as the 3.6. Which I found as odd...anyhow, I have the new tunes as my Tuner just came back from JDM with the tunes loaded..going to bring her to the local dyno guy to get my numbers (More importantly my A/F ratio) with the new tunes...probably next Tuesday. then going to get a custom dyno tune. the only thing I found out with my 3.8 pulley when a SCT guy was trying to custom dyno tune it he said that JDM was pretty much on the money and had did a very good tune for a daily driver. he said he could have made it a little more extreme...but that JDM pretty much squeezed out all they could without going too crazy on the timing. well...I am excited about it...I did find it weird that Jim stated that their tune for a 3.8 pulley was really no different than the tune for a 3.6? You would think that a 3.6 would require more fuel at WOT to keep the AF right...am I correct in that?? I was getting 11.5 AF at WOT before with the 3.8 tune. dont know yet with the 3.6 pulley or tune yet...will find out soon...GOTTA LOVE THAT BOOST

 

[thump_rrr]

The fuel is determined by the airflow. More air more fuel.

 

[cheftjpeck]

The fuel is determined by the airflow. More air more fuel.

\thx thump...so would he be right that the tune for a 3.8 pulley would be about the same as a 3.6 pulley??

 

[cekim]

\thx thump...so would he be right that the tune for a 3.8 pulley would be about the same as a 3.6 pulley??

2 things to think about:

1. if your tune/setup was marginal (i.e. pushing the limits of MAF/fuel flow/timing) - then a little more boost might be all that is needed to throw you over the edge into detonation as you have increased the cylinder pressure.

2. I have heard from multiple tuners that provided #1 is not a problem, then 2-4PSI change is typically not a problem and does not require significant changes to the tune (if any at all)...

#1 is a big problem though - particularly starting from any Saleen setup that tends to be lean for emissions purposes... Be careful...

 

[cheftjpeck]

2 things to think about:

1. if your tune/setup was marginal (i.e. pushing the limits of MAF/fuel flow/timing) - then a little more boost might be all that is needed to throw you over the edge into detonation as you have increased the cylinder pressure.

2. I have heard from multiple tuners that provided #1 is not a problem, then 2-4PSI change is typically not a problem and does not require significant changes to the tune (if any at all)...

#1 is a big problem though - particularly starting from any Saleen setup that tends to be lean for emissions purposes... Be careful...

no mine is not a SALEEN tune from the company per say. and My AF is 11-5 at WOT...I thought considering thats from a tail sniffer (After the cats) thats actually a little rich. so if I am at 11.5 is that not ok...TJ

 

[cekim]

no mine is not a SALEEN tune from the company per say. and My AF is 11-5 at WOT...I thought considering thats from a tail sniffer (After the cats) thats actually a little rich. so if I am at 11.5 is that not ok...TJ

So long as it stays that way to the top seems fine...

As thump said, within limits, the VE/load/air flow measurements/calculations in the tune will adjust the fuel as needed over a wide range of boost (as the car sees a wide range normally)...

It depends on how the tune is written of course...

 

[don_w]

2-4PSI change is typically not a problem and does not require significant changes to the tune (if any at all)...

+1

I run the same tune for 8-12psi. But, it was tuned on the 12# pulley for pump gas, and works fine at lower boost.

 

[MikeVistaBlue06]

Are you interested in selling your 3.8" Saleen pulley? That way, I can buy Doc's 3.6" pulley and decide which'un I will install!

Or have the good folks at HPP do me dyno tunes for either pulley.

Thx,

Mike

 

[cheftjpeck]

Are you interested in selling your 3.8" Saleen pulley? That way, I can buy Doc's 3.6" pulley and decide which'un I will install!

Or have the good folks at HPP do me dyno tunes for either pulley.

Thx,

Mike

sure...how much...it was only used for 1 week....make an offer...actually no scratches or anything...