Twin Turbo 928 fixed and back out there terrorizing the streets!
#196
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Location: Woodstock Ga.
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Those are awesome results! Big kudo's to you and John for building a 928 BEAST. Nothing like having a safe tune with those incredibale numbers! Enjoy the 928TT!
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#197
Nordschleife Master
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On the fuel cooler - it wasn't until I actually pulled one of mine off the car (replacing the AC o-rings) that I gained an appreciation for how much cooling effect it can provide. The internals of it are very "cool" for something that on first glance at it on the firewall makes you think "WTF is the point?" ![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
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#198
Race Director
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Is the fuel boiling a side effect of the higher flow pump? I would guess all the fuel running through the heated fuel lines, then back to the tank & back eventually heats all the fuel quite a bit?
Still impressive Dyno #'s.....all that torque down low must be a BLAST to drive..... I can just imagine what Bill would do with that![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
Still impressive Dyno #'s.....all that torque down low must be a BLAST to drive..... I can just imagine what Bill would do with that
![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
![burnout](https://rennlist.com/forums/graemlins/burnout.gif)
#199
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Congrats Tuomo! I've been following your build w/ interest on here and through Jim. Those are some great results! And it's only the first stab at tuning . . . wow. Really impressed by the low end spool. What are the specs on the turbos again? GT3071R wheel? What housing & A/R ratio?
#202
Nordschleife Master
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The car is begging for more boost in the top end. And for a dyno operator that doesn't chicken out at 6500 rpm...
Congrats Tuomo! I've been following your build w/ interest on here and through Jim. Those are some great results! And it's only the first stab at tuning . . . wow. Really impressed by the low end spool. What are the specs on the turbos again? GT3071R wheel? What housing & A/R ratio?
The turbos are the largest units that will ever be fitted in that location. They have a gt2871r compressor with a surgically altered compressor housing. The turbine has a gt30 wheel fitted inside a housing that has t25/t28 external dimensions.
Compressor and trubine maps below. The blue top line of the turbine map is what we have.
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![Name: gt3071rTurbine90Trim0p86AR.jpg
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#204
Captain Obvious
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#206
Drifting
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http://www.kuhnperformance.com/prices.php
I rode in Johns a few years back... amazing amount of power... rubber is the weak link in the equation.
#207
Nordschleife Master
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I am spending +Inf per month on the 928 stuff. That's mostly R&D and drunk-bidding on the ebay.
In terms of what's actually bolted on the car as of today, here's the breakdown:
The base '87 car in a very good condition: $16.5k
The rear fuel system upgrades: $1k
Spec 3+ clutch "upgrade": $1.5k all in and it still sucks
Twin turbo base system: $11.5k
System upgrades, exhaust, installation, etc.: $8.5k
Total: $39.5k
If I weren't planning to change the whole engine, the smart way of doing the same thing while getting the basically same results would have been:
The base '87 car in a very good condition: $16.5k
Some clutch upgrade: $1.5k
Twin turbo base system $11.5k
Installation: $1.5k
New exhaust: $2.5k
Total: $33.5k
I don't think John will ever make the base system for $11.5k + $1.5k for installation again, though. At least not when he does his cost accounting.
In terms of what's actually bolted on the car as of today, here's the breakdown:
The base '87 car in a very good condition: $16.5k
The rear fuel system upgrades: $1k
Spec 3+ clutch "upgrade": $1.5k all in and it still sucks
Twin turbo base system: $11.5k
System upgrades, exhaust, installation, etc.: $8.5k
Total: $39.5k
If I weren't planning to change the whole engine, the smart way of doing the same thing while getting the basically same results would have been:
The base '87 car in a very good condition: $16.5k
Some clutch upgrade: $1.5k
Twin turbo base system $11.5k
Installation: $1.5k
New exhaust: $2.5k
Total: $33.5k
I don't think John will ever make the base system for $11.5k + $1.5k for installation again, though. At least not when he does his cost accounting.
#208
Drifting
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Tuomo, check out Mike Simards hydraulic release bearing system with nascar type clutch. Might be able to hold more power.
http://www.simardracing.com/Flywheel.html
http://www.simardracing.com/Flywheel.html
#210
Drifting
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Tuomo, check out Mike Simards hydraulic release bearing system with nascar type clutch. Might be able to hold more power.
http://www.simardracing.com/Flywheel.html
http://www.simardracing.com/Flywheel.html