Saabscene Saab Forum - Saab Technical Information Resource banner
1 - 20 of 31 Posts

·
Registered
Joined
·
563 Posts
Discussion Starter · #1 ·
Recently there have been some topics about T7 running lean after fitting a bigger/better intercooler.

After fitting the big Elksport intercooler on my NG900, bhp has gone up from 270 to 286. This is very close to the limit of the B204L fuelsystem. 290 bhp seems to be the maximum for the stock fuelsystem (injectors, FPR, fuelpump).
The Hirsch Performance ECU is mapped for the 270 bhp hardware.

How will T5 cope with this?

Does it adjust the amount of fuel that's injected when it notices the engine is running leaner than before?

Will there be a CEL when the engine is running (too) lean?

 

·
Registered
Joined
·
8,216 Posts
You're getting more air into the engine so T5 will measure a greater air mass and inject the correct amount of fuel for that air mass. Up to the limit of the fuel system, there will be no problem.

Beyond the limit, assuming it's the same as the 9000 with T5, you will not get any warning of lean running.
 

·
Registered
Joined
·
348 Posts
Hi Rob,

to get 270, he was running the same mods as you are: 3" DP, 3" Cat Back, Viggen IC. But he has a Hirsch Custom ECU.

Yours,

Philip

P.S. @ Maarten: C U tomorrow !!!
 

·
Registered
Joined
·
4,895 Posts
Running a lot of cooling mods, such as an uprated IC, cold air intake will reduce detonation significantly by keeping the cylinder temps down. Witness Mark in Irelands 9000 Carlsson which was making 340bhp+ on the standard injectors, I also know of a T8 c900 that is producing in excess of 200bhp and that has a large FMIC fitted*. So I wouldn't assume that because you have an extra 16bhp that you are that much closer to the point at which detonation will occur.


*Keep your eyes peeled for another Midlands RR day and hopefully we'll be able to verify the power/torque and boost of this particular car.
 

·
Registered
Joined
·
563 Posts
Discussion Starter · #7 ·
Philip is right, main mods include 3" JT turboback, crossflow intercooler and the remapped ECU. The TD04HL-15T-5 turbo added some bhp as well. The complete list of modifications can be found on my Cardomain website.
 

·
Registered
Joined
·
390 Posts
Maarteen

Very interesting good website.

I still have the standard T25 turbo !!!

Having seen the Elkparts IC on a car im very impressed esp with increased power !!!

How come we always want more !!!

Rob
 

·
Registered
Joined
·
1,086 Posts
Sounds like it is doing great, Maarten! I think you should be ok, considering, with similar mods, Maptun shows up to about 290 hp on their site, or at least they used to. Anyways, I will have the same concerns once I get my MP intercooler installed and maybe an upgraded turbocharger.
 

·
Registered
Joined
·
1,086 Posts
Oh yeah, I was also going to recommend finding a dyno with wideband O2 capabilities just to be on the safe side though.
 

·
Registered
Joined
·
563 Posts
Discussion Starter · #11 ·
Originally posted by Rob12:
[qb]I still have the standard T25 turbo ![/qb][/b]
Don't change the turbo unless it's broken. When Eric had his 9-3 mapped by Hirsch, specs were almost the same as on my car exept for the turbo. Eric had a Garrett T25, I had a Mitsu TD04. IIRC it made a 10bhp difference.

/john's car is a good example of how far you can push a T25. He's using the Elksport intercooler, 3" downpipe and a Hirsch catback exhaust.
 

·
Registered
Joined
·
390 Posts
Maarten

Yep seen Johns car its very quick and the intercooler is the size of my house !!!!!!!!!!!!!

I doubt I would change it until it blows up !!

Rob
 

·
Registered
Joined
·
1,044 Posts
Witness Mark in Irelands 9000 Carlsson which was making 340bhp+ on the standard injectors,  [/b]
That was also with the standard intercooler, however I now have a full size 70mm thick one which Allards made for me and I have left my old intercooler with them to assist anyone else who wants a bespoked cooler making.
Mine cost £420 all in including postage and its a nice job too....just don't have the time to fit it
With regards to the T25 turbo, I reckon they can last as long as the boost is kept to about 1.4 bar max, I ran 1.6 but the 4 wrecked turbos on my bench is testimony to the reduced life span.
 

·
Registered
Joined
·
11 Posts
Are you running water injection,also i think you may need bigger injectors as i've had to change to t7 ecu and now pushing 326 bhp.
 

·
Registered
Joined
·
1,448 Posts
Originally posted by Maarten (900 Hirsch):
[QB]Recently there have been some topics about T7 running lean after fitting a bigger/better intercooler.[/b]
I don't see any reason why you should run lean. I recently discovered that T5 is a freak amongst MAP sensor fuelling systems; it doesn't measure static pressure like all other MAP sensor'd cars do. The MAP sensor in the T5 throttle body faces "into the wind" so to speak. That means it measures total pressure instead. At any given total pressure and temperature of air through a fixed size throttle body, the mass-flow is constant. The same cannot be said for other MAP systems which use static pressure.

If there is an increase in airflow from better VE or drop in intake temps, even though the "boost pressure" (static pressure in disguise) remains the same, the MAP sensor will sense the increase in airflow and fuel accordingly.

It's rather ingenius actually and I'm suprised more other manufacturers haven't caught on.


Adrian W~
 

·
Registered
Joined
·
288 Posts
A tuner who has played around with these cars alot told me that T5 cars do generally run leaner after IC change. He could not give a specific reaon why this happens, but it does.
Might be worth to get the car tested after mods just to be sure.
 

·
Registered
Joined
·
11,343 Posts
I had the AFR checked on the rolling road after fitting my large intercooler. Car is a T5. AFR is absolutely fine.
 

·
Registered
Joined
·
8,948 Posts
Likewise, I've not had an IC yet (money...), but lots of other bits and mine is running a verry nice AFR down into the 10's

Andrew
 

·
Registered
Joined
·
1,086 Posts
...which it the reason I would think Maarten is coincerned with. I do remember Maptun's upgrades peaking at 290 hp before upgrading the fuel system. So if he is at 286 hp, he is pretty close to that.
 
1 - 20 of 31 Posts
Top