EGT Noob, Please Help On Turbo

[TurboDragon]

Had my Dragon Turbo out for the first time today, ran good with the starting numbers but my EGT's hit like 1200-1300f at cruise 5300 rpm. 1/3 throttle, and the EGT gauge was flashing, so I thought must be too hot. Added fuel and bottom end got soft/laggy, got temps down to 850-950f though. Hard to keep temps under 950f and keep running crisp. where should I be at temp wise? a-f was around 12.5 as well. probe is about 2" past the y-pipe if it matters. Kinda ruined the day but didn't want to burn down the first day. BTW running almost straight VP C-12 (maybe 1/4 tank 93 premium was left in the tank if it matters). Kinda wish I had the EGT's when it was stock just so I would know what is normal. Thanks for any help.

Bud

btw it snowed about a foot or more today! crazy!

 

[rockinmranch]

What turbo are you running?

 

[pinit]

from what I have been told egts and turbos don't work very well together I think that the turbo causes extra pipe heat which makes the reading high.

I will help as much as I can. I have a buddy that ran an egt in his stock sled ran it in the 1250 degree area. He put a areo turbo now runs in the 1400 degree area.

how did it run at 1300 and was your a/f gage at 12.5 when your egts were at 1300. I have had many modded sleds ran them any where frm 1275-1350 never melted a piston yet. I would not recomend running a non turbo sled over 1350 that is very close to melt down. hope this helps Rodger

 

[mattymac]

Turbos can run warmer than NA sleds, I know of a few that actually run 1500 on their EGT's. I also have seen probes that bend from the extreme heat! What turbo are you running? (that makes a diffrence) Also WOT AF ratio should be in the mid to high 11's.

At part throttle you have all the ignition timing there thats why sleds run just as hot at 1/2 throttle than at WOT.

 

[TurboDragon]

Thanks for the advice, I guess I can run it a bit hotter then I was. I'm running the new Boondocker turbo. Using their numbers at wot my a/f was at 11.5 which is good I think, but once temp hit about 1000f I would let off, at idle it's around 16 a/f (is that o.k.?). at 1/3 throttle around 5300rpm it was around 1300f and I pulled over and adjusted fuel in that range thinking it was too hot. It was snappy though, the flashing egt gauge just freaked me out I guess. Pulled a plug and it was brown and clean? Thanks for the posts.

Bud

 

[speeddemon]

Thanks for the advice, I guess I can run it a bit hotter then I was. I'm running the new Boondocker turbo. Using their numbers at wot my a/f was at 11.5 which is good I think, but once temp hit about 1000f I would let off, at idle it's around 16 a/f (is that o.k.?). at 1/3 throttle around 5300rpm it was around 1300f and I pulled over and adjusted fuel in that range thinking it was too hot. It was snappy though, the flashing egt gauge just freaked me out I guess. Pulled a plug and it was brown and clean? Thanks for the posts.

Bud

well on my TM7 BDkit . 1325 is max on egt's before ur gettin to lean 1300 is perfect on a hard pull thats where u make max HP. 1050-1100 on the trail is not to bad cruzing . if u feather ur throttle did they come down at all? and the a/f guage at idle is 14.5 and 12-12.5 at cruzing speed and on a hard pull 11.3-11.5 is perfect any highr on boost ur gonna play with DETO!!! not sure if the dragon is simaler im sure it would be close though
mike

 

[turbo800]

I dont have my a/f guage on yet, but from my egts you can be either rich or lean and have high egts. With a turbo 2 stroke you can actually be pushing unburned fuel into the exhaust. That extra fuel burning in the exhuast can cause high readings. Havng both EGTs and A/F guage is optiumum. You can always do it the old fashioned way and check plugs to confirm these two.

 

[F-Bomb]

http://www.f-bombracing.com

Go to my website and read up on the DIGATRON TECH page. Read up and follow those instructions exactly and you will be good to go plus have a better understanding of how EGT reports relate to your application and engines in general.

With time you will get comfortable with tying the EGT reports to your AF lamda readings at various RPM's and heat soak rates and even get a more accurate understanding of your state of tune.

 

[TurboDragon]

Thanks to all that posted, I have a much better understanding on where I should be running. And to F-Bomb for the tech writeup, I'm feeling a lot better about tuning my sled now. I can't wait to get back on the snow and dial this sled in, thanks again