top gun said:Ok, you just spewed a bunch of useless garbage......now what kind of times does your 275 twin turbo run and which intercooler?
You're a mean bastard aren't you......
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SignUp Now!top gun said:Ok, you just spewed a bunch of useless garbage......now what kind of times does your 275 twin turbo run and which intercooler?
Ok, you just spewed a bunch of useless garbage......now what kind of times does your 275 twin turbo run and which intercooler?
Postal, If my turbo is out of its range at 22#s on a 76,What is the range on a 71 turbo? <But by what you are posting My GTS 76 Turbo is good for 800 Horsepower? And the one Ted had also???
postal said:There are a couple of people that this IC is flat out not working for. They have concluded that its a P.O.S for thier application. I need to ask some serious questions and then make a decision. Ted and Otto ran a GN-1 / 76 turbo combo, Andy's combo will be Stage 2 heads / 88 turbo. If I ran a relatively low boost 9.50 with the S2/88 combo will this IC work good, or will it still be a P.O.S. Mainly and most importantly I would like to know a few details of thier set ups to help me make my decision.
Otto and Ted:
There are people out there building up stage motors for the first time, some like myself may already have a Cotton FM sitting there. I can't speak for them but I know if you guys took the time to answere those few questions in my previous post it will help me make my final decision on wether I should keep or sell this IC.
Thanks in advance: Jason
postal said:Jack Cotton and his IC have both been singled out
postal said:Laz, Otto, and Ted to answere these questions that I can think of:
1. what brand and size radiator
2. what brand and size cooling fan set up
3. fan shroud set up
4. a/c condensor or not
5. any special IC scoop or airflow deflectors
6. method of cleaning the IC core and last time it was cleaned
7. whats the gap spacing between the IC and the radiator
Jason
Then how do we really know it's not "Evil Otto" signed on?LV GN said:Sorry i just saw i was signed on Lens Name.But its nice out here in Vegas
You can't stay off the computer for one day can you? I won't be there till' tomorrow. Be sure to let us know how paul and glen calahan do with the car.LV GN said:1 Custom aluminum 2 1" cores 31x19
2 Ramcharger fan ( enoigh tro keep car at 160 all the time)in 100* weather (BPG)
3 part of fan assembly(not sure what electric fan doesnt have a integral shroud)
4 No A?C condensor
5 no scoop, But intercooler was boxed on the sides
6 nevercleaned intercooler, Air filter does a fine job job there(Never had turbo failure, so no oil or foriegn material would be present)If your speaking of the frontal area, i have blown it out,and washed it out.Not sure of another way that would make it cleaner,
7 Not quite sure but intercooler is mointed in location specified by intercooler builder. radiator in stock location.
Hope this helps
Otto
Sorry i just saw i was signed on Lens Name.But its nice out here in Vegas
325DR said:top gun - which off the shelf intercooler do you recommend based on the intlet temperatures? TIA
Cheeseburger said:Maybe Ted can make a pass and swap intercoolers with you and do some back to back testing, same day/temp/track/altitude etc? I know, i know p.i.t.a!
I just bought a Cotton's front mount at BG this year and have ZERO miles on it and it was not mentioned to me about a more efficient design coming out soon........
Or maybe i got it backwards, the higher the mph the more heatsoak.........i'm going to bed,lol.
postal said:A 76 turbo's peak efficiency island is below 22.5#'s of boost and below around 650hp. It has a pretty good compressor efficiency all the way up to about 32#'s and approx 800hp. It has a decent efficieny up to about 39#'s and approx 850 hp. This easily shows why a V8 guy would say that they suck at high boost, where as a V6 guy may say it did fine. The V8 guys will have to keep the boost moderate. If the V8 starts turning up the boost, the HP level will climb to high, and the 76 compressor will get real inefficient trying to pump that much air at that higher boost. Turbos should not be selected for a HP level or a boost level. The proper way to select a turbo is to determine how much HP you're going to make AT a selected boost level.
If you guys are at 27 psi and over about 750 or 800 hp at that boost level then the 76 isn't working at a high efficiency. Ted's turbo test measured after the IC. Even it Ted would have measured at the turbo outlet there would not have been a big temp difference unless he's a good bit over 800 hp. Its getting late so I'm to tired to do the math right now. If ether of you had a real good guess of what HP level you're at I could do the compressor efficiency calculations for you. Also keep in mind that if you get your IC outlet temps inline the compressor section will have to pump even more air at the 27#'s. That can be calculated also if you're curious.
Jason
TurboJim said:I get what you're saying Jason. A car capable of flowing 700hp of air and still able to push enough excess air to generate 27psi, may be being overworked and generating heat, whereas a 700hp car, making 22psi will be flowing substantially less air, and heating it that much less. Actually, turbo efficiency has nothing to do with "boost" it is all about airflow thru the housing as I understand it. At 40000rpm the turbo will surge as there isnt enough flow to keep the wheel spinning, at 80000rpm it may flow whatever, 1000cfm, in My car that would be say 35psi, but in Ottos car might be 20psi, and at 100000rpm, it is flowing say 1500cfm, again, in my car 45psi but Ottos might be 30psi. My car will heat the air more due to compressing the air in the intake (45psi vs 30psi), but we will both need more IC since the turbo is getting hotter to flow the same amount of air in both cases, I will just need MORE IC. I'd think this is why the v8 guy at 30psi is different than a V6 guy at 30psi. The V8 will naturally be flowing more air (2 extra cyls) and the turbo will have to work that much more to build 30psi in the manifold, pushing the turbo out of its efficiency area.
I think the best test, would be back to back as Otto said he was planning on. Change nothing, sorry Bruce, dont touch the tune, dont touch the boost, simply swap IC's and see what changes.
But since you guys are WAY over my head, maybe I should just STFU