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Discussion Starter · #1 ·
Just fitted a bigger intercooler, had to do it the hard way...drain coolant remove radiator and create new fixing method for the air/con rad.

Took it out for a spin yesterday and noticed that my boost pressure has increased from 1.2bar-1.4bar.

Prior to fitting it would spool upto 1.2bar and level off at 1.1bar...now it will spool upto 1.2bar as before but instead of levelling downwards it will rise upto 1.4bar and stays there all the way to the red line.
I have only tried this in 3rd gear at the moment.

I am not complaining, I am enjoying the extra
I was just wondering if this was normal and if others had experienced the increase in boost pressure.

Steve
 

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interesting

what you have done is reduce detonation especially at higher air flows where the turbo is being less efficient and heating the air more normaly the apc will "pull it back"
the new i/c is taking that heat out and taking it away from detonation..this is the best case scenario
1.4 bar on a t 25 all the way to the redline is very very impressive you are talking about a major boost in hp...

watch your fuelling tho...
 

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Discussion Starter · #3 ·
Originally posted by ylee coyote:
[qb]1.4 bar on a t 25 all the way to the redline is very very impressive you are talking about a major boost in hp [/qb][/b]
Sorry should have said, changed the T25 last year now running a T28.

Steve
 

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Nice one Steve. Look forward to seeing the difference at the next RR day. So how did you fix the the air-con rad? I'm looking for inspiration.
 

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Steve, I noticed the same rise in boost pressure when I fitted a KJ 50 mm IC to my B234R. I think there are two principles involved here: flow and thermal efficiency, of which flow is probably the more predominant. The stock IC is known to have a large pressure drop associated with it, so most of the rise in boost pressure is due to this, I would think.
 

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Yup, I had exactly the same. You need to re-set your base boost pressure. Any IC has a pressure drop across it, the performance ones less so.

The lower intake temps will help peak boost, but the increase is primarily due to the reduction in resistance.
 

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Discussion Starter · #9 ·
Thanks chaps good to hear it's normal, will check base boost during the week, if I do need to change it I hope it needs changing down and not up as I only have half a turn left on the rod....I do have a spare shorter one though just in case

Aerogav
On the 9k there are 2 holes at the bottom either end of the ic...on the plastic part, with a similar setup on the air/con rad. These two are then bolted together at the bottom with locating pins on an L bracket for each at the top.


The hiflow ic does not have any holes at the bottom (mine hasn't)so you cannot fix the air/con rad to it.
For now I have just made a tempory fixing using some galvanised strapping that I had, fixing it to the holes at the bottom pulling the rad up into the locating hole at the top and screwing the ends behind the grill...2 torq screws located either side of the grill fixing screws. In doing so I have increased the spacing (airflow) at the bottom.
The permenent fixture will be two brackets at the bottom and a modified L bracket at the top bringing the air/con rad further forward increasing the space and airflow between the two.

P.S I have seen other posts here indicating that some people maybe thinking of fitting thicker ic's than 50mm, this woud not be easy as everything moves back i.e closer to the turbo I now only have 15mm clearance between turbo and plastic fan cowling...not yet melted
The a/con is not a problem as that will move forward, from what I noticed when fitting mine is that the 50mm is as far forward as possible to fit a thicker one you would have to do 1 of 2 things.

1. Move the locating pins to the back of the ic, for this to work the height of the ic would have to be less than standard (370mm)say 350mm or 355mm.

2. Modify locating pins and holes for the ic having it sit further forward and lower than the origional. "confused" the panel above the ic slopes forwards and down and would have to follow suit.

Just my thoughts on the 9k

Steve
 

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It is possible using the standard fittings with a 50 mm i/c
however there is lots of space in front so a bit of metal work/zip ties it should be possible to fit a thicker one

Plastic fan shroud ?
mine is steel (and rusting at the top !!)
turbo clearance is not much
it is a real squeeze with the gttb30 I would estimate aboout 5mm gap
 
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