Interesting post....
Phillip

 

I wonder if we can get some of the high dyno guys to tell us if they have ls6 maf's or maf ends.. Also I would like to know what their intake manifold pressure is at the higher rpms.. This might explain why some that have identical H/C packages dyno much lower than their counterparts who have maf ends or ls6 maf's..

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by LS1derfull:
<strong> Vince, i will explain pressure drop than you will understand about why maf ends will help make power, atmosperic pressure is free for us to use like a free supercharger, if you can get full 14.7 psi(at sea level) into engines cylinders, and keep it there as motor winds up in its power band. If you keep a stock screened maf in there anmd that causes pressure drop, you may only get like 13 psi into cylinders past maf. So you see its like losing free boost into motor. Now i feel its worth mentioning that real powerful LS1 motors can also start pulling vacuum(pressure drop) because of small intake plenum size and long runner lengths that LS1 style intakes are known for. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">100% correct. But it is great to get rid of the restrictions BEFORE the manifolds so the manifold can be assessed on it's own <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

That's whty I used the head and cam senario...some of our big inch stuff still runs into trouble. <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />

 

I just got a sweet deal on some CNC ported MAF ends, I'll be heading to the dyno to try alittle testing of my own. Report back in a couple of days.
Phillip

 

Keep us posted..

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by phil97svt:
<strong> I'll be heading to the dyno to try alittle testing of my own. Report back in a couple of days.
Phillip </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Where do you dyno at in Md? <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Thanks

John

PS - Sorry for the thread jacking Vince. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

 

Not a prob.. I want to see if he gains anything from the maf ends..

 

Vince make sure you are comparing apples to apples with MAF ends. Picking up power with MAF ends does not mean it came from using a different end. Unless the timing and A/F ratio are 100% the same between runs you couldn't draw any meaningful conclusion.

The item to look at is the MAP. 2-3 runs with stock ends. vs. 2-3 runs with ported ends.

Tim

 

Thanks Tim.. I need to find a Tech 2 to watch my MAP while I do some runs..

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Tim Sloper:
<strong> If you could eliminate the pressure drops in the intake tract the car would make more HP.

Tim </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Or install some sort of device that INCREASES pressure in the intake tract... HMMMMMMM why doesn't someone invent something like that??? ;-)

<---MASTER OF THE OBVIOUS!!

 

I dyno @ Tempest Racing in Waldorf, MD. This dyno session I am shooting for 450+RWHP.
Phillip

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">The only issues with SD tuning are that

1) While WOT tuning is pretty easy part throttle will take some time to get accurate (if you're concerned about it)

2) The PCM won't accomodate atmospheric changes well. This will require more attention to the tuning as weather changes.

I'd say if you have a track only car then go SD but if the car must be driven as a daily driver I'd sacrifice the HP and keep the car running as efficiently as possible.

</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Comes down to careful tuning - yeah SD is a lot harder to tune , but thats what I get paid for <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

Every load point has to be mapped rather than relying on the MAF to sort it out. Drivavilty and performance are great if done properly.Normally takes at least 2 days on the dyno to get it 90% right but it is so worth the effort on a cam/head package

 

What other things could I look at to check to see why my intake manifold pressure is dropping..? I want to take a look at it all b4 going back to the dyno.

 

Vince,
Here's something to consider. The TB opening on both the LS1 and LS6 factory intake manifolds necks-down to between 72 & 73mm before dumping into the plenum.
I'm going to stick my neck out and say that messing with the MAF will have minimal effect on MAP readings in the plenum unless this neck-down area is addressed as well.
It's this same neck-down area that I feel has caused people to doubt the usefullness of bigger throttlebodies on the LS1. How could a bigger TB add much power when the intake still chokes the air path?

 

Are you saying go with a aftermarket intake? Have you seen the prices of those things? Until one of our Vendors come up with better pricing and a intake that would produce more horsepower over the current ls6. I think we are stuck.. Unless there are other ways to keep 14.7 from dropping..