[s-cars] Ball bearing turbo

[Jim Green]

On 10/18/05, djdawson2 at aol.com <djdawson2 at aol.com> wrote:
>
> No... the GT30 has a 76.2mm (3 inch) major diameter on the compressor
> wheel. The 3071 has a 71mm major diameter. The advantage is a quicker spool
> up (lower threshold), and improved surge characteristics (higher PRs are OK
> at lower engine speeds). The cost is high end flow, resulting in a peak hp
> loss at high rpm. The gain in low and mid range power is really nice,
> however... more fun than RS2, as it seems to hit earlier than I remember the
> RS2 setup doing in my car.
>
> So... the comp housing is different, and so is the wheel. As such, you
> will require at least the CHRA, and the compressor housing. The turbine
> section is exactly the same as the GT30R, so you could probably swap your
> turbine section onto the 3071 CHRA.
> HTH,
> Dave
>
> Dave, good info. Sorry if you've already posted this, but how's the GT30R
act at Denver's altitude? I searched and found your post about the dyno, but
it looks like you may have had some ECU issues at the time. Have you or
anyone else ran a GT30R uncorked up here? If so do you have the uncorrected
dyno #'s? I thought Hap was going to run one, but I haven't heard anything
lately. Stuff like when does it hit full boost, how bad does it surge, or
does it when you step on the gas in 4th at lower rpms,
 I'm looking at going 20vt with a fully built block, mildly ported head, and
the full 034 manifold treatment. Basically Javad's motor, my 034EFI IIC ECU
and a GT30R with very little wastegate :)
 I'm looking to get a solid 450 uncorrected WHP hopefully on 91 octane and
water injection. 500 would be nice on race gas.
 Thanks!

--
Jim Green
'89 90tq
'89 80q
http://www.mswanson.com/~jgreen/car_home.html