Of course it's 'laggier', but that's not what you said:

This makes absolutely no sense. Go grab two compressor maps, say for a GT2871R (as that should be close to the stock turbo), and a GT3076R. Calculate the mass flow rate of air for the pressure ratio Joe was running at 7k rpms, and see where that falls on the compressor maps of the 2871 and 3076. Then you'll understand why the stock turbo falls on it's face and the GT30 does not (the equations are on the garrett turbo website).

 

So why did you use the Megan manifold?

 

Turbo lag has very little to with how late the torque peaks, unless the turbo doesn't spool until after peak VE is reached. Power is going to fall off at some point on any engine, and that has nothing to do with the turbo, it's the VE of the engine.

The ability to hold BOOST(not torque) to redline is a combination of compressor wheel and turbine wheel efficiency.

 

What is your rpm range when tracking your car? The cars makes more whp/ trq from just beyond 4500 rpm to redline and substantially more higher up. I'm not sure what Joe revs his to, but I go to 8k and that would give him 3500 rpm of power advantage over stock. When would you ever drop below 4500 rpm on a road course?

It looks like his new turbo would spank his stoker on the track. On the street, loosing that low end would be noticed, but not on a road course.

 

Joe,
You have obviously shown great patience and did this comparative test on your own dime. I for one have been confused by all of the negative press regarding the ATP kit from the non users when the majority of the users had positive things to say. I would hope that ATP reads this thread and appreciates the time you have taken to attempt to show an apples to apples comparison. BTW, it is a good thing this worked out, the internally gated GT30R and GT35R turbine housing are very expensive!!!!!!

 

He used it because of the way the runners kind of bend into the weird hotside. If he hadn't used it there would be more of an abrupt change from the stock manifold to the hotside. It would have to take a sudden turn, whereas with this one it doesn't appear so. It's more gradual. That probably helped spool some compared to a stock manifold.

 

Its nice to see another ATP kit perform as well as mine did, good job and good write-up.
Now all the ATP haters with zero experience can STFU, but probably not.....

 

 

Nice number!!Congrats on your new finding.

 

I thought thats what I said.....this would be better on a road course as oppossed to an auto-x course. I did not think I could be any clearer.

Lets not lose sight of the fact that Smokin did this on a Evo IX with MIVEC. When the Mivec was off, his spool was even crappier. So...he admits this freely. I think the past results of ATP kits on the Evo VIII models still stands. Anyone disagree with this?

 

Ok I am very new here but I have to say one thing... Why would people not beleive that ATP can make power. I mean its absurd. I have read numerous threads which are more than 8 pages each with people who are using ATP products saying that they luv it and still people who have no experience with the kits are so adamant to make them feel otherwise...

Did i mention I am putting one on my car soon ... No offense to anyone... All in good fun...

 

Nope not agreed, an 8 with good cam setup and cam gears will yield very similar results.

 

I think there could be some truth to that. Logically it makes sense, too However, the real difference is the cam timing can be continually adjusted on the IX, where on the VIII its a static number. This may or may not impact top end performance.

Someone has touched on a good point that I've yet to hear before - and that if you have a VIII - work the cam timing to build up cylinder pressure. B/c it appears a signigicant amount spool gain can be achieved.

Someone also said that with the Mivec off - the spool was crappy. Not so, the spool only mirrored Sam's GT3076R spool rate on his Vishnu kit. With an .82 ar, its expected.


Just because a company like ATP, DB or Vishnu built the kit - doesnt mean that you cant make it better by dissecting the components and adding complimentary parts. Like the Megan header. It was a cheap upgrade that I felt gave the exhaust the correct transition to the housing.

 

i disagree...25 psi i did 440whp with the exact same atp kit on EVO8. but whatever lag is generated from this kit is caused by the custom hot side. I Will be swaping out the atp hotside with a new t3 Vband 3inch out side from atp matted with a PEakboost T3 manifold but will be keepng the 3037 turbo. This should hopefully spool faster and give more top end...this swap should happen in about three weeks.

 

What does your curve look like - not just peak.

Tuning the engine makes a HUGE impact. I didnt break 400hp until the 8th or 9th dyno run. Keeping the boost the same the entire time.

The right tune could make or break the performance.