C4VetteLS1

I see alot of turbo cars with EGT gauges, but ive never really known how to interpret them, can someone give me a rundown about different EGT temps and whats to lean and whats not? what do look for at different boost levels..?

Rob Raymer

Depends on where you locate the EGT probe and what type of fuel you are using.
The probe should "ideally" be located within 1-2" of the turbo inlet (Hot side). If you locate it after the turbo outlet, temps will be a lot lower, therefore allowing you to tune for much higher peak temps...make sense?

So lets assume the probe is located "ideally". If you are using pump gas, I never like to see more than 1500 degrees at peak on the EGT. I shoot for 1400-1450 with an AF of about 11:1 on pump gas.
With race gas (typical 110 octane), you can get away with a little more. When running race gas only, I will tune it for 1500-1550 at peak, and about 11.5-12.0:1 max AF. If during a run at the track, or on the street, I see it hit 1600 on the EGT, I let out of it. Some people run C16 (118 octane) at even higher EGT temps. I've even heard of some Turbo Buick guys that will actually tune for 1700-1800+ degrees on C16! But personally, I think that's a little too risky. FWIW, on straight C16 I'll shoot for 1650 max.

Hope that helps.

HUGGER ORANGE SS

iTrader: (2)

I have my EGT sensor on the Driver side Y pipe right around where the cat should go.. I think I have it too far away from the header for it to be any use.. The highest I have seen it go up to was almost 1300 deg F at WOT and a long pull in 4th gear. On a blower type of aplication where should the sensor go?? Clint

lbz34

iTrader: (3)

We typically run Japaneese gauges. Greddy is the cheapest of the "good" gauges. I like to see no more that 900 deg C. Usually we like to keep it around 800 under WOT. They are th most accurate 1 inch from the head in each runner is etremely expensive and accurate. In lieu of that I would go with the leanest cylinder. Maybe #2??

LASTLS1

iTrader: (7)

I would think anyone is NUTS to put the temps going to the turbo in excess of 1250 F. You risk your impeller blades flying off going into your motor! Aluminum starts to fatigue at 1300 f. I have burnt up many pistons at 1350 F. If your installing probes coming out of your cylinder It should be 6-8 inches from your piston skirt. Call egt for exact probe location. If there in the wrong location you my as well not even install them. Good luck with your set up.

y2khawk

iTrader: (5)

first, turbine blades aren't aluminum. Second they are after the motor, so no flying in that way

At work, 1700° about 2 inches from each port was the bogie to shoot for.

I had an autometer EGT gauge in the "collector" of my short incon manifold and it was basically useless. Full gauge was 1600 and it would peg anytime at WOT.

I've got an 8 channel EGT setup going in for each runner, and will continue to use 1700 to 1750 as my bogie.

LASTLS1

iTrader: (7)

Rob, where do you locate the probes to run that type of exhaust temps? I've never heard of such high temps. The motor just sticks before you even get to 1400 f. And that was running C16. It was on a two cycle engine, but aluminum shouldn't know the difference. I know you are the turbo guy, but I would love to know. Thanks.

LASTLS1

iTrader: (7)

Well don't listen to me, I guess my application is different than yours. BTW I thought the impeller blades on the intake side were aluminum. I wasn't refering to the exhaust impeller. Oh well I would call EGT and ask them. They were right on, on my application.

y2khawk

iTrader: (5)

Not to be an ***, but EGT is Exhaust Gas Temperature.

Not sure who the EGT you're refering to is, but the EGT here is exhaust. And FWIW, if any one ever saw 1200° on the compressor side of a turbo they would have more things to worry about

red ws6 99

The EGT should be located 1 to 2" from each exhuast port, one on each cylinder like harlan stated. It should be used to determine cylinder to cylinder variations, which knowing the AFR on each bank of cylinders you can then infer a rich or lean condition. Its not meant to be an indication of AFR directly. This is how only way they can be used and is the same way they are used on airplane engines.

Putting an EGT in the collector before the turbo will give very high temperatures and won't tell you much at all.

Gary

Whistler

iTrader: (46)

I'll just have to call EGT myself and get the real scoop. I dont want to melt my turbo blades.

LASTLS1

iTrader: (7)

EGT, Exhaust Gas Technologies , the company that makes the product in CA!

Jammer

iTrader: (1)

What product do they make...sensors? gauges?
Is there a scanmaster type product ...Harlen...how do you read your egts... not 8 seperate gauges...whats the instrimantation you use?

y2khawk

iTrader: (5)

My own

8 analog inputs and 8 k-type TC inputs per little box. 1Mbit CAN link between the boxes and the Laptop. Yes, i'm a geek

Jammer

iTrader: (1)

So...short answer is, forget all the gauges, have the laptop...if thats the case I am onto something as a venture company at a local polytechnic institute is installing a "computer" in my daily driver (for e-faxing, printing remotely, internet, gps, mpegs etc.) This cpu can do everthing a laptop can, but utilizes the flip up screen head unit...Your givin me expensive ideas.