I would like your input on which turbo will help me reach my goal of 600hp? I would like an all around turbo but can't decide which turbo.

 

for 600whp you will need something bigger then the hta 35r. as it is smaller then the regular 35r just the blade is billet. the hta3586 may get close but that is also a stretch. the 6765 is a good turbo for 600hp but will be a bit laggy compared to a hta type turbo.

 

Do you think a pt6765 is laggier than a t66? cause thats what I have now

 

for 600 SAE rw rotary hp you need 80 lbs of air per minute.

the GT3586 may put out 70-75 pounds. there is no compressor map but the turbo output can be reverse calculated from various piston dyno sheets.

the PT6765 is a 67 mm turbo w enhanced delivery due to it's billet compressor. a normal 67 mm turbo makes 73 pounds at slightly over 29 psi... that's 550 SAE rotary. based on piston dyno sheets the 6765 probably makes 10% more air but at high boost levels.

FWIW, my objective is 600 rw and after examining all my options i chose the GT4094r.

assuming the HTA3586 does make 73 pounds of air i would be concerned that is still retains the smallish turbine wheel that is on the GT3582r.

cold side compressor area is 6.839 sq inches
hotside is a small for the output 5.171 or 75%.

not really great for the rotary. higher backpressure and EGTs.

hc

 

a 6765 should spool the same a t66 maybe a touch better if you get the billet.

 

hey howard... what about a comparison between the s366(xl) and the gt4094 turbo?

 

When I talked to pte, they rated the billet 6765 at 90 lbs/min.

 

Howard I greatly appreciate your input. So the gt4094r would me the best choice. It would be great if some people on the forums chime in on how they like there gt4094r.

 

I find that hard to believe.

 

You haven't seen this video Rich? http://www.youtube.com/watch?v=Bb6T12yhDv0

That is 92 lbs/min right there. I wasn't joking when I told yah the turbo pulled the same if not harder at 16 PSi then the 500R-SP felt at 20 PSi.

thewird

 

yea i was a non believer as well until i saw some videos and spoke to pte myself. i was told the 6265 which i plan on picking up soon flows 75lbs. i wouldnt doubt the 67 flowing 90.

 

So I am guessing the pt6765 would be better than the gt4094r to help me reach my goal?

 

Why is your HP goal so high? 2 rotor wankels are not know for elevated HP levels and longevity. I hope you have lots of money and patients. Good Luck on your quest.

 

i am running the 6765 with the H housing. i have a street port that consists of exhaust porting ( advanced) and the primary port matched to secondary's. i have a v mount intercooler set up with my turbo on a long runner manifold and its not laggy at all. granted its not a billet wheel but that's more icing on the cake. PTE turbos are awesome and make great power, not saying garret doesn't but PTE is the the bang for the buck. and yea i think they will make more power than a gt35r

 

Think he is comparing it to the gt4094r to the billet 6765. The 35R will not make 600 rwhp. From all the available information, I'd say the billet 6765 would definitely be the better choice.

thewird

 

I think PTE6765 Dbb .96a a/r FTW

 

It should be right around 89-91lb/min.


Definitely. The 4094R just wont cut it. You would be working the turbo too hard all the time to make consistent and reliable power.

 

how come these evos can push more power out the turbos than what its rated at? Makes me think

 

the evo can run 900psi of boost so that helps. ha no in all honesty they run 40-50psi on these turbos. most strong rx7s run mid 30's. the evo's just love boost i run my stock turbo on my evo at 30psi

 

i do agree w most of what has been posted above...

one of the more interesting aspects of the recent (at least recent for non pro racers) billet wave actually comes from Garrett. after putting out a BS piece comparing two compressor wheels that were identical except one was cast and one was billet and finding no diff as to output, shazam, a few months late they roll out their billet line and surprise, they published comparative compressor maps that if accurate are mind blowing.

for example at two pressure ratios (14.7 psi) the GTX4294R does 80 V the old GT4294R at 70!

one of the reasons i didn't go w the billet 6765 is that the crazy top end hp it has produced was above 40 psi. i have zero interest in running above 30 psi and i will be very close to 80 pounds at 24-25 w my GT4094r.

OTOH, the new Garrett billet compressor maps show HUGE advantage for their billet wheels at rotor motor friendly boost levels.

can you imagine if you could duplicate their GTX4294r flow advantage to the compact GT35r footprint. you'd have a turbo that could sit alongside the motor rather than infront of it and produce a legitimate (80/70) 73 pounds of air for 550 rw rotary hp swinging a modest 6.8 sq inch compressor.

Garrett has to be ramping it for SEMA, my bet. of course it would need a larger hotside than the current GT35r.

" s366(xl) and the gt4094 turbo?"

there are so many BW tags... i believe you are referring to what i have as the BW S366SX.

cold side 66.1 X 91.4 or 7.743 sq inches
hot is 73.4 X 79.8 or 7.151 nice size for the rotary at 92.3% of the compressor
78 pounds per minute at 40 (!) psi
69 pounds at 14.7
between 4088 & 4094

"So the gt4094r would me the best choice"
it was for me but there were other considerations such as my perceived build quality and the package size for my new CPR engineered manifold as well as my lack of interest in running anything more than mid 20s boost. all purely subjective on my part and non-binding on others.


"35R will not make 600 rwhp"
correct if you believe the compressor map.

"It should be right around 89-91lb/min."
correct based on a number of legitimate dyno runs and quarter mile performance. the question for me is how does it work in the lower boost areas... probably quite well but like many of us, i am waiting to see the rotary SAE dyno charts.

"The 4094R just wont cut it. You would be working the turbo too hard all the time to make consistent and reliable power."

disagree unless you are saying that i am looking to make 600 rwhp "all the time." where would you do that? my car is dual purpose. street, road racing where i will run just enough to blow people off (probably 450) and the 600 is just for the Texas Mile which is 30 seconds at 600 hp and will be run using nothing but methanol. if you are looking to make 600 hp all the time...

i look at billets as a step forward and will be just as interested as you all to see some actual dyno sheets. i also look forward to Garrett filling out it's billet line.
\
howard

 

Every engine is different and 4G63 or for example ECOTECs are exceptional engines in terms of combustion efficiency...

 

just not fair lol. I would like to run 30psi all day long but can't. What is the efficiency of the pt6765 at what boost levels. please chime in

 

I just heard today that a lot of the bigger Precision billet turbos are breaking their compressor wheels. Something about being too thin... scary

 

The piece that Garrett released was comparing cast vs billet compressor wheels of a nearly identical spec. The purpose was to show many that its not the material that makes the difference(many nay-sayers were under the impression everyone was being duped into buying a BS product). Garrett has a few large frame compressors, like the 91mm, that are produced in cast and billet versions.

The Garrett compressors are designed more for mass flow than increased pressure, whereas the Precisions are designed for very high pressure while still being efficient.

The S366XL is a 66mm compressor that was paired with an 83mm(if I remember correctly) turbine wheel for class racing. There is also now a BW S400SX 67mm, which uses a new compressor and the 83mm turbine wheel, the turbo is designed for class racing as well.

What I meant by working the turbo hard all the time, is if he were trying to make 600whp, the 4094R would be at the ragged edge and could be over spun rather easily, which over time will kill the turbo rather quickly.

Any idea if this has been verified? I dont really see it happening easily except in the case of compressor surge, but would be interested in seeing the aftermath.

 

at what psi will the gt4094r and the pt6765 reach 600hp?