Infini IV

Anyone running a .81 turbine A/R with a Q-trim wheel on a streetported 13b? This, on the HKS cast manifold.

I'm trying to decide between the above and the .96 P-trim... The .96 P-trim has been used plenty of times on the HKS cast with good results in the top end I believe, but I'm curious to know how a smaller housing and larger wheel would do.

Carl Byck

I'll be running a TO4R .81 Q trim, but it will be about 30 days before the car is done, I would choose it over the p trim (obviously).

mark57

I changed from a 0.96 to a 0.81 on a stock port and that helped tremendously on the low end. A streetport may do well down low on the 0.96. I am P trim.

IAN

iTrader: (3)

How much of a difference will it be for a .81a/r. Can anybody say they were producing X number of hp at 3500?opposed to the .96 at the same rpm?

I was told that that was to small so I want with a .96a/r. At the time everybody was recomending 1.00a/r ratios.

I prefer street power but I am street ported.

jgtcspec7

iTrader: (19)

I have a HKS TO4R with the .81, and the stainless divided manifold. Not sure if it's the Ptrim or the Qtrim. I've read conflicting posts on the forum about this matter.

The TO4E HKs sells has a .84 a/r. I can't see the E making more power than the R. Maybe I will give HKS a call, and find out if it's a Qtrim or a Ptrim.

Anyways I still have to break in the new street ported engine. I will quickly put 1000 miles on and post dyno sheets soon. Should have the car back on Tuesday.

Infini IV

I wouldn't think a .81 Q-trim would be too small (maybe a P-trim)... but I'm not too knowledgeable on the differences turbine housings and wheels would make.

It just seems that a .81 could offer greater power at a lower RPM without suffocating top end too greatly (although boost response would/should suffer).