Saabscene Saab Forum - Saab Technical Information Resource banner
1 - 12 of 12 Posts

·
Registered
Joined
·
249 Posts
Discussion Starter · #1 ·
A friend fitted a boost gauge to my 9000 2.3 FPT, at the weekend. On full throttle it is showing 2.0 bar off boost, then tails of to 1.3 bar.

This is on a standard 165,000 mile car, is this normall ?

Since I am still waiting for the correct gear box, I have been driving with the close ratio non turbo 2.3 box, this makes the car super fast and very un-economical, but would this make the boost go this high ?
 

·
Registered
Joined
·
2,041 Posts
Your gearbox shouldn't affect your boost - at worst you would hit the rev limiter the same as you would in any car using too low a gear for the job. My modified GM900ST hits about 1.3 to 1.4bar and tails back to 1 bar. 2.0 bar seems a bit high - what does it read at idle/over run?

Mike
 

·
Registered
Joined
·
608 Posts
2.0 bar of boost/28psi ??

Wow that sounds very high for a standard car...my abbott ecu'd only hits around 18psi

It must go like stink with that level of boost...although I cant see it all last too long before it goes bang !
 

·
Registered
Joined
·
4,895 Posts
Thats very very high, people won't believe mine's standard and thats running about 1.6 BAR on overboost. Sounds like either the gauge is reading too high or your car is not detecting knock for whatever reason.
 

·
Registered
Joined
·
249 Posts
Discussion Starter · #6 ·
I thought it was the gauge, so I have tried 3 different gauges but they all read the same. The boost is very odd, most times it will peak to 2.0 bar on full throttle, but some days it will only peak to 1.5 bar.

DO you think the APC may be faulty, and that I need an MBC ?

Overboost occurs at about 2.2 bar, where it does the usual fuel cut off.

Yes the car is alot of fun, there is nothing better then making this list, 330 ci, CLK320 and TT225 move over to a J reg saab!!

but as much fun as it is, I am worried about the engine going bye bye !!
 

·
Registered
Joined
·
14,305 Posts
I'd say someone has played with it- there's no way overboost cutoff should not be coming in to 2.2 bar!! Normally it will be about 1.7-1.8 bar absolute max.

I'd also be very worried about potential damage. Your turbo won't be up to supplying that sort of boost long term, and I would expect that there is probably also some knock ocurring. It could be an APC fault.
 

·
Registered
Joined
·
1,219 Posts
APC is seeming to be sticking, as stock should be somewhere around the 1.4-1.5 mark i think... i dont like mbc's so i am not going to say get one, as that is up to you....
 

·
Registered
Joined
·
249 Posts
Discussion Starter · #9 ·
I just tried another gauge, this is the fourth one !just incase !! this one is in P.S.I and reads upto 20PSI, but the guage went of the scale, so that was no help.

I have just found a spare APC, so I will put that on and report back after testing.
 

·
Registered
Joined
·
8,216 Posts
Originally posted by Grentarc:
[qb]stock should be somewhere around the 1.4-1.5 mark i think...[/qb][/b]
Should be around 0.8 or 0.85 bar. 2.0 bar sounds too high even for a modified car. Those cars listed should move over for a lightly-modded 2.3 FPT.
 

·
Registered
Joined
·
1,219 Posts
i was wrong about the boost.. .sorry about that, its just i thought that it must have been around that mark to get the performance of them.. ahh well...
 
1 - 12 of 12 Posts
Top