Actually I did some digging through Dyno4mances website, and it appears the owner of the car in this thread actually just has a lot of lag...interestingly here is a car with the same size turbo on the same dyno. Vishnu Stage 3 car on same dyno and here is a stock turboed car on the same dyno just to give you guys/the owner an idea of how laggy it is Stock Turbo Car on dyno4mance DD .

Hope this helps, and to the starter of this thread, check for exhaust leaks pre turbo.

Scorke

 

I was thinking the same thing DD dynos are great dynos, but they do read low. That 441 would probably be around 475+ on a dynojet IMO.

About the lag, the dyno never loads the motor the same way it's loaded on the street. You also don't really know at what RPM they hit the gas at. When going for peak dyno numbers, there is really no need to start a low rpm pull and heatsoak the motor more. As long as you are into full boost before the peak power point it works. One should absolutely never use a dyno graph to try to determine the boost threshold, way too many variables, even with charts from the same dyno, IMO. What he sees on his boost gauge/tach is much more accurate and reliable, but even better is a data log.

 

It is not any laggier than any of the other 3076 turbos I've seen, so that is a moot point. The fact that it hit 441whp on Andrew's dyno is very impressive, so impressive that I don't believe that it was only boosting 25psi. Remember, that would be 495whp on a dynojet, and 30R turbos usually take a few more pounds of boost to reach that number. That is a great running car nevertheless.

Like someone else said, it would be nice to see the boost and afr graph.

 

Actually, those numbers work out to ~507whp / 427 ft/lbs on a Dynojet.

This is on 110 oct unleaded, and the Autronic PnP board uses no knock sensor. AFAIK however, maximum advance was kept to around 14 deg.

 

TedB/Smogrunner/Kjewer did you guys look at the links I provided in my post, compaired to other cars on the same dyno with the same turbo his car is substantially laggier, pointing out the fact that maybe the dyno does not skew spool as much as we think....Goto www.dyno4mance.com for yourself and take a peak at the mitsu graphs.


Scorke

 

I certainly did, and that is why I made it a point to say that there are still too many variables, even on the same dyno Looking at multiple dyno runs from my car from the same day/same dyno, what would be interpreted as boost threshold is all over the place. It's not worth arguing this information against readings from the tach and boost guage, there is no comparison in accuracy and reliability/repeatability. And to reiterate, I try to get all boost threshold data for all of my various setups I've run from a datalog, which is even better, especially since I started logging boost (DSMlink).

 

Keep in mind that I can demonstrate significantly different spool characteristics on the same car, just with a twist of cam gears. Take two different cars with the same turbo, but with different cams and whatever else, and there can be significant differences. Just take into account the fact that the torque curve for the car in this thread peaks some 300rpm higher than the car in the link you quoted, which can be attributed to something as simple as different cams. Naturally, the car with the higher rpm torque peak (all else being relatively equal) stands to make greater peak hp, at the expense of some spool time.

 

I hear ya ted however if you take a peak at dyno4mances site they do a very good job of recording what mods cars do and do not have. Personally after looking through lots of there sheets, I have come the the conclusion that this turbo IS laggy, to me there are too many instances of cars with similar turbos(two other cars there with vishnu stage2/3) along with countless stock tuboed cars with all similar plots, to make me believe that THAT big of a variance can be held down to the dyno, and not the car....

Scorke

 

FYI:

The only Stage 3 charts on Dyno4mance's site are 3037s, not 3076s. The one you pointed to was done back in Feb, 2004 (over two years ago), so think about how far thinking has come since then. HKS 280s were not even available back then, and neither was an IC comparable to a Nisei, so we know said car had smaller cams, smaller turbo, and a lesser IC. This being the case, we can hardly compare these cars as being equal. We do know that the present 3076 car makes a lot more power.

The only other 3037 car on the Dyno4mance website used 100 octane and made a lot less power as well, but we cannot realistically compare spool characteristics from two different turbos as being equal - they aren't. We don't know what else was in that car either.

Keep in mind that Noize's 3071R made 409whp on that same DD dyno, which is more than either of the 3037 cars on the Dyno4mance website. But we can't realistically compare spool characteristics of the 3071R as being equivalent as well - it isn't.

What we can do is remark about how we tend to see more power from smaller turbos these days, which attests to the maturation of the performance market and a better understanding as to what works.

 

First thanks for conversing, I like threads where things actually get discussed!!!!!

What is the difference between a 3037 and a 3076 ,AFAIK and from what everbody else has said/been told the 3037 is just a rebadged 3076...... 401 whp is that far off 441, granted its a difference its not huge by any means.

Scorke

 

Several different versions of the GT3037 and GT3076 are the same. This particular car looks like it is using a GT3076-13 or a GT3076-15 due to its higher power output and extra lag. My GT3076-12 spooled alot faster, but would have a hard time making more then 450whp on a Dynojet.

 

A 3037 is not just a rebadged 3076R. My understanding (AFAIK & FWIW) is as follows:

- 3071R has a 71mm / 56 trim compressor and a 60mm / 84 trim turbine.

- 3037 is an HKS hybrid of a Garrett GT37 76mm / 52 trim compressor with a 60mm / 84 trim turbine, so it is essentially a 3071R with a GT37 compressor.

- 3076R is a Garrett GT35R 76mm / 56 trim compressor with a 60mm / 84 trim turbine, so it is essentially the same turbine as the 3071R and 3037, but with yet a different compressor.

- GT35R is a 82mm / 64 trim compressor with a 68mm / 84 trim turbine.

 

Great posts guys.

Ted:

I thought a 3076R was a 76.2mm 56 trim compressor with a 60mm / 84 trim turbine?

 

Ah, you may be right. After all, why would it be called a 3076 otherwise? LOL

If that's correct, the only difference between a 3037 and a 3076R is as follows:

3037 - 76mm / 52 trim compressor

3076R - 76mm / 56 trim compressor

Confusing innit?

 

Yes, quite confusing haha, ok, so even though the 3076R and 3037 are slightly different, how much power is in that difference?

Scorke