FWIW: Don Cruz has been 173+mph at 3460# with an 88 turbo and Champion heads, so I would say they are getting close
For the record. I do realize that if I were to bolt on a better set of heads (Stage II), it would be a quick and easy 400 bhp or so. I'm just waiting for the Stage I head technology to get to a point where it is even with or surpasses the capabilities of the Stage II head. That way I don't have to change my manifolding. If you know what I mean. :biggrin:
Exactly. For example, we have flowed a set of decent Stage 2 heads that topped out at 340cfm. A good set of conventional heads have been 320 on the same bench. The port size of the conventional is much smaller than the stage head and the engine is noticeably more torquey down low.
I'm confused. What heads exactly are you running? Stage I style or Stage II style? Above you stated Stage. What does that mean?Im curious at what boost level you think you would have to be at to make a quick and easy 400 hp more with just a head change. For the record A Na motor would gain nowhere near 400 hp with just a head change so i dont see how a turbo motor would gain that. Years ago Cal ran heads that flowed 250 cfm and dave and I ran our stage heads all three of us ran the pte88 turbo guess what, we all ran 159 mph the only difference was that Dave and I did it with 5# less boost.
Is this some kind of trick statement?For the record A Na motor would gain nowhere near 400 hp with just a head change so i dont see how a turbo motor would gain that.
I'm confused. What heads exactly are you running? Stage I style or Stage II style? Above you stated Stage. What does that mean?
Is TSO limited on manifolding and turbine size? What kind of ex/int pressure ratio is TSO seeing?I was running old school Champion heads and Tony and Dave were running Stage 2 heads. We all three were running the same the same turbo, etc.. We all had nearly identical performance.
I tune on Fiscus, Gomes and Cruz's cars, and based on what I am seeing so far, I still haven't seen a dramatic hp increase with the Stage heads in TSO trim. Not dealing in theory, basing it on personal experience.
BSFC is around 1.15.Don, what is your backpressure at your peak boost? Also how much fuel are you using?
I was running old school Champion heads and Tony and Dave were running Stage 2 heads. We all three were running the same the same turbo, etc.. We all had nearly identical performance.
I tune on Fiscus, Gomes and Cruz's cars, and based on what I am seeing so far, I still haven't seen a dramatic hp increase with the Stage heads in TSO trim. Not dealing in theory, basing it on personal experience.
Is TSO limited on manifolding and turbine size? What kind of ex/int pressure ratio is TSO seeing?
They are a small part of a TOTAL package. But the heads are still an important part if the package is right. For instance, my package has outgrown my heads.BINGO, real world experience!!! heads are a part of the puzzle on a turbo car its a smaller part.
Either Stage I or Stage II heads are legal in TSO?
Either Stage I or Stage II heads are legal in TSO?
They are limited to a maximum turbine exducer diameter of 93mm/3.66". Most racers are running smaller than that. The pressure ratio varies slightly based on engine combination, but a good rule of thumb is around 1.8:1 on the faster cars.
They are a small part of a TOTAL package. But the heads are still an important part if the package is right. For instance, my package has outgrown my heads.
So some are choosing to push some big boost numbers.
