gfelber

Wow, I see that reading comprehension is not one of your strengths.

Did you miss the part about "I'm not saying these improvements aren't noteworthy"??? Where did I state that "cars putting down 450WHP are just running too small of a turbo"?

What I was speaking about related to the exhaust side for the 30R AND 35R vis-à-vis a rotary applications.

Garrett spends a lot of money on advertising and R&D to develop and produce very good products. Garrett has done much lately to affect market share lost to Japanese competitors and it shows (hence the use of "frenzy"). Turbocharger design has improved recently, but it's not enough to _vastly_ affect one's turbocharger selection. For example (again), compare HP results using differences of 5% in compressor efficiencies on a reasonably efficient intercooler and look at the results. Let us know what you find

My point is that a relatively cost effective approach can yield rewarding results. Older turbos (including Garrett designs) can work well. If you failed to make that conclusion then revisit the original post. Again. And again.

Gene

pluto

I agreed, the ratio is a good guideline for the beginners. I'm sure that you already knew there is more than just a ratio to go by when designing a turbo kit. flow characteristics, efficency, surge limit, runner length and diameter just to give a few.

On a side note regarding your "full boost" and "too small" comment. boost pressure and air flow are independently proportional to each other. Having a turbo that spools fast does not always mean it'll flow right at those level.

pluto

My engine is a 1/2 bridge. Full boost is relative and depends on what I considered full boost. I get around 28psi of boost at 5.5krpm w/o n2o and made 470rwtq and 570rwhp. A 75hp wet shot yields me full boost (28psi) at ~4.6krpm and 610rwtq (last dyno and unknown hp since i was getting break up above 630rwhp at around 6.6krpm). Based on my last 1/8' mph (6.4@114mph) and extrapolate my estimated 1/4' mph (somewhere around 145-146mph). My car is estimated to make around 730rwhp with a 2985lbs car. Don't ask me how I get more than 75hp out of a 75shot n2o, it does..... I'm taking out 200lbs, adding a bigger turbo and running more boost this year so we'll see how far I can go before it breaks.

razorback

wow..impressive numbers. now all i got to do is get my car started...do you happen to know anything about the apexi safc2?

pluto

The SAFC2 isn't much different than the older SAFC. They increased the # of tuneable datapoints from 8 to 12.

Zero R

iTrader: (1)

Right on, basically the same wheel in the GT40.
It's a great comp. wheel, but I like the 88mm wheel In the 40R just a little better.

Zero R

iTrader: (1)

Yes, all of these are very important. You may change to different wheels or ratios to help obtain the level of flow characteristics, efficiency, surge limit, runner length etc. that you're wanting. The ratios I provided are "guidelines" for good all around performance. And may not hold up entirely true when getting at the levels of modding we are at. But I prefer not to go too far out, when talking on here for the exact reason I stated above a lot of people poke around in here and grab things posted without fully understanding the how or why agreed?


Very true.

Zero R

iTrader: (1)

Thank you, this was exactly what I was refering to.

No more posting from me I'm starting to feel I've ruined Jason's and Gothams thread.

artguy

the conversations in here are exactly the reason that the single turbo section of the forum is by far the most intelligent and informative.

i appreciate the info guys.

thank you.


j