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ATT and KOJO tune for my 97

Yeeee Haaaaw!!!!!! I want to hear more! But first you got to wipe that silly grin off your face and remove the lead from your right foot. I know, I know, it's going to be hard to do for a while. But, I am interested in real world MPG figures.

What you just finished setting up is what I think I want. I want economy when I'm DDing my truck, and pulling power when towing my travel trailer. I really am interested in how things go for you.

Don
 
TMHark said:
ATT, FTB and boost fooler - Wow! A bit of smoke at take off and then you feel the boost build. The 5-10lb boost range pulls WAY harder than my GM8 set at 12 with TM. Bit of an exhaust haze until turbo spools up. Locked up in OD, this beast roars from 60 to 90+(ran out of road with more left in it!), it feels like like a carb with vacuum secondaries opening when you hit the sweet spot, like it suddenly has another gear at 70mph . Very impressed (and this with stock programming). If the KOJO (or Heath) tune can clean up the extra fuel down low, clear up the haze, and bring back some of the bottom end snap, I will be a VERY happy camper!:thumbsup:
Click to expand...

Sounds like I might end up drivers license challenged when I finally give in and make that order that has been on hold in my mind for an eternity. You say it really shines at 70+mph but I actually rarely see that kinds of speed, most of my time is spent at sub 50mph really. How is it at those speeds (3.73's)? But I guess the "extra gear" kicks in sooner while pulling a load right? Ironically I want it because of the extra power while towing, but I'm not sure the horses I'm pulling will appreciate the new exhaust note the way I will... ;)
 
More feedback

As turbo wears in, it is quicker to boost and actually maintains a couple pounds at highway speeds (65-ish). When it was new, it was much slower to boost and smokier, and would drop to almost no boost at cruise until it was revved back up.

I still had a pretty good haze, and EGT's that seemed a bit high, so KOJO and I conversed via PM (very quick to respond and helpful)

Since I am flowing a LOT more air, I thought it may be time to revisit the relatively small cone style air cleaner that came with my SSD intake kit. It was fine with the stock GM8 and programming, but Kirk is now yelling to Scotty for "a lot more pow'r!" :hihi:

I did have a couple parts left to rob from my old intercooler kit and built this:

air cleaner.jpg

It a factory style K&N I had laying around with some cobbed up, a-hem, I mean CUSTOM tubes to attach it. I threw together a quick heat shield and will likely box it all in.

So... now with an ample flow of air...
EGT's are much lower and slower to climb
Pulls my boat like it's not even there, 0 to 65mph quicker than most traffic accelerates
Downshifts to third actually shoot you forward, instead of just making noise
Can now hear turbo. Not a whistle like GM, but more of a building "whooosh" like a jet
Just did a run to 100mph and never saw 1100 degrees
And this is all with the 3" exhaust and hotrod muffled system!

Very happy with ATT and KOJO, and many thanks to Tim, KOJO, Dennis and all who have helped me out on this adventure :tiphat
 
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We cleared up some of the smoke and 1214 codes he was getting, I suspect operator error by tech that set up his IP initially not knowing Snap-On time set conventions don't work like the GM T2 does. When I got there with my MT2500 since I've a lot of been there done that with it , I found his base time to be @ 6.5 deg in time set, we readjusted it so that it was avg 3.8/4 which cleared the coding and the heavy smoke trail now you get a respectable puff @ WOT but clears quickly, TDCO also now @ -1.95 now.

One thing with the KOJO tune @ WOT you go to max fuel right away max EGT 1300F @ one point IIRC, which means with this re-flash you MUST RUN WITH GAUGE & MONITOR EGT. one caveat this was with open air box sucking direct under-hood air

The acceleration with Kojo vs the test Heath I'm running are on par, Heath program seems holds EGT back to 1100 which for towing IMO is a plus as there is some built in safety margin if one is not paying attention to EGT, Bill is in Bonneville so I need to talk to him some more when he comes back to town.
 
Turbine Doc said:
One thing with the KOJO tune @ WOT you go to max fuel right away max EGT 1300F @ one point IIRC, which means with this re-flash you MUST RUN WITH GAUGE & MONITOR EGT. one caveat this was with open air box sucking direct under-hood air

The acceleration with Kojo vs the test Heath I'm running are on par, Heath program seems holds EGT back to 1100 which for towing IMO is a plus as there is some built in safety margin if one is not paying attention to EGT, Bill is in Bonneville so I need to talk to him some more when he comes back to town.
Click to expand...

Is this actually true, or just what it seems like? Different trucks, differnt exhaust, different intakes. Seems like you can't really judge that. Did scanner actually go to 80mm3 off the line and yours it doesnt? Or did you try both on your own truck. Changing the program is simple, I wouldnt judge todays tune off of future ones.
 
True & verified with MT2500 scanner both trucks, I read before & after EGT's & fuel rates stock vs KOJO tune in Terry's truck.

I've been around enough trucks/programs to know it's more than a subjective feel, not saying anything wrong with the KOJO tune it requires more operator vigilance though as it really rolls the EGT quick.

One feature that is a difference is the 3" exhaust, which may allow for a more rapid building of EGT; we'd have to try a 4" to know if that is a component of what is going on.

I did not swap truck to truck as no theft deterrent to be learned in Terry's WT model truck my PCM would not work in Terry's truck, and I doubt his would have worked in mine for same reason, we did not have enough day for me to try it in mine as it is a 30-40 minute learn process if you don't have the GM T2 tool to do an instant theft deterrent module/code learn and I did not want to possibly upset what was working in both our trucks late in the day.

My Heath hits max fuel 80+mm off ht e line then backs out as truck comes up to speed with some neat shifting & TCC locking features, in comparison the KOJO stayed at max fuel according to my scanner until letting off the throttle in Terry's.

Buddy if you wish let's discuss further in the Heath tune thread in 6.5 performance rather than dilute Terry's thread any more with Heath vs KOJO
 
Exhaust OR WMI???

So I boxed in the air cleaner to only get air from the fender opening and my under-bumper super redneck ram air tube

Truck performs great, but no better/worse than before the boxing in of the air cleaner

EGT's still run up pretty good, 1200 on an empty high speed run, I think we caught a break at last testing due to cool moist ambient air helping keep them down

I know Buddy and others have mentioned a 4" exhaust as being a necessity, at this point I am considering WMI or doing a 4". I really like the sound of my already paid for exhaust that's on there... SO.... Exhaust OR WMI???
 
The larger exhaust will help the turbo spool faster and higher to get more air into the cylinder for lower EGTs. It is install it and forget it.

If I had a scanner I would compare timing, I am guessing that Terry might benefit from a little higher timing at 100% throttle.
 
Terry how's the truck running, ever get a chance to run by your mechanics to see what Snap On tool he's using and compare those numbers to the numbers I set your TDCO to with my MT-2500, or run open exhaust to see if it made a difference in the EGT rate/peak of climb?
 
Yes let us know if he used a Brick(MT2500) or a Solus. I am curious as well. FWIW My Heath tune hits 1300 no problem either with a GM8. 1300 egts=Bad. Aluminum melts at like 1250 or something.
 
No more testing until next weekend

More testing will have to wait till next weekend, as we have a family emergency in Florida (have to fly down last minute type of thing) and won't get back to NY until Thursday night

When I do get back I'll pop the exhaust back apart up by the downpipe and give her a few hard pulls and watch the EGT. I've noticed the 4 inch exhaust systems all have 3" downpipes that open up to 4" where the cat used to be. It really makes a difference opening up to 4" after all that exhaust has been restricted to 3" for three or four feet in the downpipe? Well, I guess it must, or why would everyone buy/recommend it

It's strange how it EGT's are inconsistent. Today I had to go to 95mph with foot to floor to get anywhere near 1200. But it is overcast and pleasant out. Other (hotter?) times it jumps right up there anytime you hold the loud petal down for more than a few seconds and ATT hits 10-11lbs. The cooling system works great, it rarely goes above 180 unless towing heavy, even with several high speed runs back to back. Scanner actually reads temp of 165 most times, so I don't believe it's cooling related

I know my big beast (7600lb empty!) is no dragster and maybe the weather conditions, weight, etc are the culprit in the changing EGT's, because I know it just can't be the amount of lead that has found its way into my right foot in the name of "testing" :rolleyes5:

Oh, and just so I don't get flamed for high speed runs with such a nimble vehicle, there is a very seldom used rural road with a giant straightaway that I use for these purposes. No traffic, police or anyone to get hurt if something goes astray. Might make some hamburger if the cows are near the fence :eek:
 
Well just got back from FLA today and it was 95+ degrees here in NY
Temps weren't low today!
Daughter has horse show tomorrow so it was right back to work
w horse trailer.jpg
Truck tows great, just drive by EGT
Had no trouble with this 6k (with two horses) nag hauler
Even schooled the Mrs - "1200 = BAD" and had her drive a bit
I'll see if "open header" (disconnect just past downpipe) makes a difference this weekend, but I can't leave it unmuffled around these skittish equines
 
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Open pipe "testing"

Ole Yeller and I took a rutted unplowed tractor path today to get out the snowmobile for an upcoming trip.

Well, it was way deeper than expected and although we did climb out of there unassisted, it did afford me the chance to test "open pipe" as the snow and ice chunks separated the muffler from the 3" pipe as it tried to high center us :o

So...

Way quicker to boost
Saw 15lbs boost for first time
Breaks tires loose at will (at take off and 1-2 shift)
Way lower EGTS, 95mph uphill WOT and didn't see 1100
But, since it's just dumping under the bed, crazy noisy, vibration, etc

Maybe I'll try replacing the muffler with a 3" straight piece...
:hihi:
 
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