StatoJase

Hi I have just run down the track with my 408 gt47 combo and pulled a 10.3 @ 132. Car felt good and I logged the run to have a look at what all the sensors were up to and noticed the iats had hit 155f at the end of the 1/4. But looking at the timing it had dropped to 6.5 degrees at the 155f mark and started pulling timing once iats hit 100f mark. Running 14psi boost and had 15deg timing before it started pulling.

I am starting to work out what my inefficiencies are that are causing the intake temp rise. I am upgrading the turbo in a few months to a gt55 on advice from a few people on here so could it just be the gt47 too small causing the rise or should I be testing my intercooler and efficiency stuff? A 90f rise through an intercooler is pretty large to me but I am still learning. Any thoughts?

Tally TransAm

iTrader: (17)

what intercooler and what were the iats when the run started?

StatoJase

After the skid the iats were hovering around 90f, ambient air at the track was 62f but it started at 82f before the skid. Intercooler is a 24x12x4 with 3" in and out no name cooler. maybe the sensor or engine bay is heatsoaking as the car sat for 15 mins between the 2 runs and I logged the second run.

StatoJase

So my run IAT starts with 90F, is at 155F at the end of the 1/4 run and eventually settled back to the 80F mark after idling the car back to the line up. with ambient air of 62F.

SPRAYED 01

iTrader: (22)

That sounds right. i have the same ic and mine get to 150 by the end. If i spray a single15 nozzle they go from 150 to 79

Tally TransAm

iTrader: (17)

really?

my cheapy cx racing one will go from ambient and only rise like 23-25 deg during a whole run.

WSLN 6

iTrader: (3)

With my Powerstroke ic, I go from ambient and end up with a 10-15 deg gain in a quarter run. At 132mph, your turbo should not be working that hard. What boost level?

Forcefed86

iTrader: (4)

Depends how much boost and the fuel your running. Nothing wrong with those iats On e85 IMO. I run the same cooler. Iats around 160 with ambient 84 degrees. Around 100 In the Burnout box. Thats at 20lbs. Timing sounds about right to me for pump gas. On e85 imo you shouldnt pull any timing at those iats.

Dont believe the bs claims that alky drops your iat that much either. The sensor itself gets saturated and the alky evaporates off it giving a false low reading. The air entering the motor is no where near as cool as the iat sensor claims.

StatoJase

I am running 98 pump fuel (in Australia), and the car is primarily a street car. 15psi boost on a forged 408 bottom end. Not really pushing the car hard yet as I want reliability. I have no real interest in meth injection just yet. I have been told many times now my gt4708 is too small for the cubes and will blow head gaskets and stuff so was wondering if this is the primary cause for the higher IATs. This gt4708 is a diesel unit with a 76mm inducer on the front. This diesel turbo was one I picked up for nothing and tried. Just think this combo is leaving alot behind if I only have 7 degrees of timing through the back half of the track.

CameronVic

iTrader: (5)

That's literally unbelievable. Lol. You're telling me your A2A is twice as efficient and my A2W with 30lbs of ice in the trunk. Quit making stories up. Unless your run is like 200' and your car is on 4psi, I'd bet money it's nowhere near what you say. Got a datalog? Cause I'll sell my a2w tomorrow and buy the inter cooler you have.

OP, sounds exactly like what my old A2A did. If its on E85, you don't have to worry about pulling timing till its above 200*. Not sure if its on 93 or corn though.

Edit: I see its on 98 octane, I don't have any experience with that so I can't give you any suggestions. Got room for an A2W? Lol. I picked up about 9-10% more power just getting the iats down 90-100*

StatoJase

98 unleaded is normally the higher than standard octane pump fuel available, No e85 available where I am at the pump. It may not be that detrimental with these iats but I am not really content leaving the grunt on the table because of it, considering I am not pushing my combo that hard in the scheme of things, 7 degrees of timing seems low for a forged low comp stroker. Since it was on a fairly mild night it can only get worse when summer hits if I just run it.

SPRAYED 01

iTrader: (22)

Maybe those who post results should add where their iat sensor is. Mine is 3inchs from the tb and the meth nozzle is 12 inchs from the iat sensor.

Forcefed, I don't doubt you are correct about false iat readings with meth. But have you done any actual testing to confirm? Like at iat sensor drilled into an intake runner right before it hits the valve.

Tally TransAm

iTrader: (17)

then you can LITERALLY sell your inefficient setup. if your air to water setup is twice as inefficient as this, you did it wrong. sensor is about 4" from the throttle body

14 psi, 93 octane.

before run 90 deg iat




post 10.39 @ 136, 113 degrees



thats 23 degrees for those not good at math


I can post another log if you want of the same intercooler on a 370 S480 car i built gaining a whole 11 degree's IAT during a 4th gear 800 rwhp 2500-6600 dyno pull in mid june 90 degree heat.

Realcanuk

I agree with Forcefed on this. I have been saying this for ages but no one listens. On a PD blower like mine, where the sensor is nearer the valves, the temps don't drop nearly as much with meth.
Spraying meth directly on the IAT sensor is like spraying cold water on a thermometer. It will read cooler, but the air outside is still the same temperature.

Forcefed86

iTrader: (4)

What CX racing unit was this? I'm not sure if I can get the boost that low, but it does seem to be doing a damn good job.

Thanks!

Tally TransAm

iTrader: (17)

the 31x12x4 one that cost like $150.

not saying there arent better intercoolers, but having used them on cars up to 800 rwhp, it gets the job done just fine

CameronVic

iTrader: (5)

You spraying nitrous and/or meth too? That's gotta be the slowest reacting IAT sensor on te earth because that A2A defies physics. Lol.

Tally TransAm

iTrader: (17)

youre right, the multiple cars that run these are wrong.

dont you have a few more motors to pop before you go preaching about physics?

i've run this same intercooler on 3 cars that display the same results. im sure theres others on here that have similar data. maybe you should keep your lol's to yourself and learn.

CameronVic

iTrader: (5)

I'm surprised it took you this many comments to make a stab at how many motors I've popped. Lol. I bet I learned more in those 3 junkyard motors than you'll ever know. And yes, I know that IAT sensor is wrong. Mine goes up 32* on an 8th mile pass (6.58, well faster than you I'm sure). If A2A's were more efficient than A2W, every X275, ODR, outlaw 10.5 etc would have them. I could show you a dyno of my car making 1000 WHP, doesn't mean that's what it makes. If your A2A really keeps the iats that low and your sensor is correct, you should hold onto that thing forever, because it's definitely one of a kind.

Tally TransAm

iTrader: (17)

i never said a2a was more efficient than a2w. its pretty common knowledge its not. i said yours is wrong/incorrect/flawed/whateveradjectiveyouwant if at a 6.58 power level your gaining 32 degrees over ambient over 660 feet. And with a tank big enough to hold 30#'s of ice . . . yeah . . .

hell ive built top mount whipple cars that dont gain that much and run in the 6's @ 4000#'s and those are well known for high iat's

why dont you show your a2a data that contradicts mine? i'd be interested in it. if you dont have any then all you're doing is arguing a moot point you have no evidence on.