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Discussion Starter · #1 ·
Okay, I've managed to do a deal and am getting a bespoked intercooler made, one thing I've stipulated is the inlet and outlet are 3" to match up with my turbo 3" intake and Ylee's 3" manifold intake pipe.
This contradicts Saab design where the flow path it reduced in diameter before and after the intercooler.
Anyone have any ideas if keeping a 3" flow path from intake to throttle body is the best approach.
 

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More of a theory than a statement I'm afraid Mark, but I look at your question in this manner.
If we assume (sorry, know) that hot gasses expand and cooler gasses contract their volumes for a given mass then the outlet of the intercooler need not be as big as the inlet. Since I know not of anyone who has fitted a larger (higher efficientcy) intercooler to their Saab (and rolling road tested it before and after this single change) I guess you'll just have to suck it and see. Can't see it doing to much harm though, except perhaps with throttle response / spool up of the turbo at the bottom end? Top end power should be better if this is the most restrictive thing. What other mods do you have Mark?
Nick.
 

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Originally posted by cdcarlsson:
[qb] Since I know not of anyone who has fitted a larger (higher efficientcy) intercooler to their Saab (and rolling road tested it before and after this single change) I guess you'll just have to suck it and see. [/qb][/b]
I have ...but not on a 9000. I have just done the "after" rolling road session on it today. I did a "before" prior to it being fitted. BIG difference


Mark - diameters of the IC in and out pipes were left standard, whereas core is significantly larger. Engineer was looking at enlarging the IC outlet side and the whole intake pipe up the the throttle body - but we have not done this yet.

Nick - we should meet half way for a pint of Harveys
 

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I think the reason for using 2" dia tube as stock is simply that it's easier and cheaper to get hold of.

I can't see any problem with using 3", after all it's going to lower the resistance (albeit very slightly).

I suspect that as it's such a short length of tubing, the bigger factor is how smooth the air flows from the inlet to the core and the core to the outlet. Any turbulence in these areas would give more resistance.
 

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Discussion Starter · #6 ·
What other mods do you have Mark?
 [/b]
Gas flowed head, water/methanol injection, different cams, 3" JT exhaust, no cat, GT28RS Ball bearing turbo, mbc plus the modded air intake which I made at work, tied to an ITT huge air filter.(thanks for the info on that Ylee)
Unichip say they can fit a piggy back ecu to sort out the boost and fuel mapping.....I don't know whether its me or Ylee who is first in the queue for that piece of kit!!
 

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Originally posted by Rob12:
[qb]John

How much of a difference ??
[/qb][/b]
10% increase in power recorded on rolling road session after having fitted the larger intercooler
 

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Originally posted by /john:
[qb] QUOTE
Originally posted by Rob12:
[qb] John

How much of a difference ??
[/qb][/b]
10% increase in power recorded on rolling road session after having fitted the larger intercooler [/qb][/b][/quote]Hi John

Do you think this is mainly down to better cooling or less resistance to the air trying to pass through the intercooler?

Kev
 

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I suspect the difference is down to more efficient reduction of inlet temperatures. High inlet temperatures can really sap the power, so reducing them helps get colder, denser air into the engine to realise more power.
 

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Mark,
I can see why you're looking at an upgrade to the intercooler . I'm still left pondering whether the effects of intake bore size on pickup / drivability verses top-end power are as valid for turbocharged engines as they are for normally aspirated ones? Perhaps you'll come back to us and let us know?
Nick.
 

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Originally posted by Rob12:
[qb]John

Thats impressive 10% of a lot is a fair amount, so what did the rolling road show you as putting out ? [/qb][/b]
Johns car was up from around 243 to 270bhp yesterday at the very conservative Emerald RR - my old 900 was up to 260bhp from 240 previously.
From experience these figures are down around 20bhp compared to Power Engineering.
Saying which rr is correct is mere speculation but i know for reference a TVR Chimiera 450 recorded 232 on the Emerald rollers not long ago.
Whichever way you look at it its a serious gain and its a lovely looking piece of kit - i know John was very happy


Pete.
 

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Hi Philip

In your case the gain comes not only from intercooler because you have installed in the same time the flowed head (and intake pipe?). Am i right? But around 10ps would be fine only from intercooler .

9-5 aero
 

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I find it's not always totally meaningful to talk in horsepower terms alone for mods like intercoolers and gas flowing of heads.

Having done both seperately on my 9000, I would say that the on the road driving difference appears to be more than the suggested 10-15hp.

In particular the intercooler was very noticable during the sumemr months, when it made the car feel more like it was the winter. Saturation is also less likely to occur.

Slightly more on topic, things like bigger dia intake pipes help in two ways. Firstly they reduce resistance and thus allow more air through for a given pressure. This alone doesn't make much difference on a T7 car as it is mass metered. However I would reckon that the reduction in resistance will help reduce spool up time and improve responsiveness.
 
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