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Re: exhaust manifold



Scott,


>You know the VW 1.8 had a forged crank?

 No I didn't, but thinking about it, it seems like a good idea, considering
that the 1.8 was a stroked 1.7
 and the 1.7 was a stroked 1.6 etc...

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>Those saab turbos are pretty small...Pat Dooley from the list has a VW
>truck we turbo'd and he is using the Saab turbo.  Spools up fast as hell,
>but even with an intercooler wont run more than 11psi cuz of detonation.
>I'm tryin to get him to go with a 2.3 compressor, as we have a freind that
>runs a 2.3 compressor on a saab exhaust housing in a Rabbit, which is
>pretty much the same setup except that he hasa G grind, and no
>intercooler.  that guy can run 14-15 without knock.  


That depends on WHICH Saab turbo...
There is the '78-80 Exhaust pressure regulated wastegate TB-305s with the
"little turbine"
and the 42 trim compressor, and large turbine housing.
What I refer to as the 42 trim is the same as the Carb 2.3 turbos the
Renault Fuego turbo(which has an interesting intercooler)

There is the '81-82.5 NON-APC T-03s with the familiar boost pressure
wastegate and 42 trim compressor.
The wastegate "pot" on these is set at 8-10 psi and they are not "staked" so
that they are ADJUSTABLE:-)
The 82.5-83 Turbo differed only in that because of the APC system the
wastegate was set to 4psi and non-adjustable.

And the 84- Saabs(last year of the single cam and first several years of 16V
Saabs) Garretts used the larger 55(?) trim compressor(same "Trim" as the 2.2
Dodges, and CIS injected Volvo's)

BTW ALL 16V Saab turbos were intercooled

The EFI turbo Fords use the 62 trim compressor.

If he is getting detonation at 11lbs nothing will be gained with a larger
compressor...

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>holy shit..must had some explosive bottom end:)

Actually far less bottom end than stock, the "weak link" in a Saab 900T is
the gearbox.
and it is torque that breaks those so I built the engine for power(top end)
lower compression takes away bottom end and allows more boost in the top end,
Ditto the long overlap N/A camshaft I used, Ditto again for retarding the
camshaft.
 The engine as stock produced peak torque of 160ft/lb@3500rpm  (8lbs)  with
the little TB-305
when I was done Peak torque was above 4600rpm at 17lbs without an
intercooler and no detonation
and I only got as far as the 55 trim compressor.

 Well I did grind nearly a pound off of and out of the aluminum cylinder
head too...
(and I have another that  I had metal added to(by welding) so I could remove
even more in the right places...

 The next thing I was going to try was the 62 trim compressor wheel in a
Nissan 300ZX  housing and the Factory intercooler for the 16V engine.
 I know I can get away with "bloody murder" on this setup because the 16v
engines are running 9.3:1 C/R
and 15+lbs of boost on a 55 trim compressor...

Theoretically at least I should be able to run 20-22lbs boost on pump fuel,
WITHOUT an intercooler!!! 
before detonation becomes a problem... (and I will use an intercooler:-)

 The only concern was sufficient fuel to prevent high speed lean-out, 
as the OE CIS mechanical injection is limited to 180-190HP,
but I have a Volvo fuel Distibutor that I'm going to use and these will
allow approx. 230hp before lean out.
(and I don't need that much anyway... How much power can you use in a FWD
car anyway?)

 I am building a Saab and have been gathering the parts for several years.

I'll tell you more about it if you are even slightly interested,

Allan
Walter De Groot  wdegroot@ptdprolog.net
610-377-8632   fax 610-377-9362
If you have my AOL address it is not working now