SteveKen
February 4th, 2011, 15:05
OK, I've been thinking about this and the recent discussion of removing the aux radiators garners a separate discussion.
So the big question is how does extra HP affect the stock cooling system?
I'm hoping Mr. Balsen can chime in here, as I've seen him write that the limiting factor is cooling with the biturbo. Although, I've never seen any evidence of overheating at all, I also haven't seen anyone making gobs of HP over the stock amount.
If cooling isn't an issue, or doesn't seem to be one, then why hood vents and modifications to the belly pan? Could it be safe to say that underhood temperatures have no affect on the cooling and strictly affect IAT's?
I'm wondering if anyone knows at which HP mark does the cooling tradeoff occur? Improve IATs and IC efficiency by removing the aux rads and get more HP, but at what point will the stock cooling system be affected?
As, many of you know, I'm embarking on a manual conversion. This is somewhat related to this issue on a few fronts.
#1. The smaller transmission can free up space for bigger turbos.
#2. The manual trans can get away without being cooled, which is less taxing to the oil and water cooling.
Initial thoughts I had were to replace the stock radiator with one that doesn't have a trans cooling circuit. I don't think that running water through the trans circuit will help with water cooling as it would be too restrictive to the water pump.
Another thought was to run the trans cooling portion of the oil cooler in series with the oil lines to improve oil cooling. Basically making the entire unit a singe oil cooler.
FYI, my 4.2 S6 has an aux radiator and so do the 4.2 B6/7 S4s.
Also, the coolant after run pump. I've seen it removed on the 2.7T without any issues. With due diligence, could the same be done on the 4.2 biturbo?
Anyone have any thoughts or evidence that can lend to the discussion?
So the big question is how does extra HP affect the stock cooling system?
I'm hoping Mr. Balsen can chime in here, as I've seen him write that the limiting factor is cooling with the biturbo. Although, I've never seen any evidence of overheating at all, I also haven't seen anyone making gobs of HP over the stock amount.
If cooling isn't an issue, or doesn't seem to be one, then why hood vents and modifications to the belly pan? Could it be safe to say that underhood temperatures have no affect on the cooling and strictly affect IAT's?
I'm wondering if anyone knows at which HP mark does the cooling tradeoff occur? Improve IATs and IC efficiency by removing the aux rads and get more HP, but at what point will the stock cooling system be affected?
As, many of you know, I'm embarking on a manual conversion. This is somewhat related to this issue on a few fronts.
#1. The smaller transmission can free up space for bigger turbos.
#2. The manual trans can get away without being cooled, which is less taxing to the oil and water cooling.
Initial thoughts I had were to replace the stock radiator with one that doesn't have a trans cooling circuit. I don't think that running water through the trans circuit will help with water cooling as it would be too restrictive to the water pump.
Another thought was to run the trans cooling portion of the oil cooler in series with the oil lines to improve oil cooling. Basically making the entire unit a singe oil cooler.
FYI, my 4.2 S6 has an aux radiator and so do the 4.2 B6/7 S4s.
Also, the coolant after run pump. I've seen it removed on the 2.7T without any issues. With due diligence, could the same be done on the 4.2 biturbo?
Anyone have any thoughts or evidence that can lend to the discussion?