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mackin
12-10-2002, 21:53
Is there any reason to see higher boost levels with nippy air???Denser,heavier?

Maybe I've just been out of my truck to long but it seems the last two days chilly temps I'm seeing higher boost levels.....Climbing a moderate to light long grade 70ish light peddle pressure 23 PSI,Level 3 Hot Juice,just me, no cargo.....Seems higher then normal....Temps were in the 20 yesterday when I noticed......But it was running good!!!!! Complete Opposite on EGT'S ,no explanation necessary.....

MAC

[ 12-10-2002: Message edited by: mackin ]</p>

GM Smitty
12-10-2002, 22:14
Hey mac, it's funny you bring this up. Yesterday I was on the PA Turnpike (a very straight and relatively flat road) and I noticed my boost #'s were higher than I remember them being the last time I was on that section of the turmpike (which was when it was much warmer). They were probably 5-10 psi higher than before. I cleaned my amsoil air filter today thinking I might have let it go too long. See how she runs tomorrow.

Josh

Maverick
12-10-2002, 23:11
I run 23-24 psi year round. Right at freezing today and some snow. What did you run all summer Mack?

mackin
12-11-2002, 05:22
Mav

20 LBS or under I believe.....In the same area.....Where are you pulling boost reading from?And I's wastegate gutted......Just seeing if there may be a difference.....EGT'S were a good buck buck and a half cooler,do to the lack of bumper cover and inter cooler get a breath of fresh air .....

MAC

Allison Jettester
12-11-2002, 12:40
Mac, Yes it is because cold air is more dense. Jet engines make more thrust (compressor discharge pressure is higher) with cold air and conversely, make less with hot air. The Allison TF-41 made a lot of thrust in cold air, but was minimal when temps rose above 90. It was so bad that they installed a box that raised the temp limit for two minutes so the airplane (A-7E Corsair II) could get off the ground with full load on a hot day. The turbo is basically the same thing as a jet engine compressor.

Joe

mackin
12-11-2002, 19:54
Joe

Thanks .....

I knew I wasn't seeing things....Just a tad bit more boost in most situations,that wasn't there before....

MAC :D

Maverick
12-11-2002, 22:59
Mac,
I t-eed into the wastegate hose as per the More Power install article. I ran 19 in stock form. I have seen swings up to 26 already but it usually caps at 23-24 on level 1. I understand that this is when the wastegate is suppose to open to let excess boost go. I don't get a chance to play on #4 very often. The trailer is always in tow.

[ 12-11-2002: Message edited by: Maverick ]</p>