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A military rebuilt 6.5

Hi FT! No boost increase yet....I'm at 1300 miles right now. I'm going to get to 1500 then change the oil and filter, after then I'll start playing with the boost more.

As far as tune feedback....well.....I've found that I actually have LESS power at full throttle than I do at 3/4 throttle! I was playing the other day and found this out! It does raise the shift point at full throttle, and I've seen the throttle register 100% on Car Code so it doesn't seem to be a throttle pedal issue.

I called Bill Heath and talked to him about an hour regarding this. He looked at my tune while we were on the phone and he didn't see anything wrong with it. He of course questioned the turbo and the cam but didn't want to out and out blame them. He also thought my fuel pressure was too high. He suggested that I set it to 5 psi at idle. I tried that and it didn't solve the problem. It also didn't seem to run much different so I left it for a few days. One day I noticed my fuel pressure was at 1psi while accelerating so I bumped the pressure back up. I set it to 13psi at idle, but it has since crept up to nearly 15psi at idle! But you know what...it idles more smoothly now so I'm leaving it there.

On a whim I tried changing the compressor housing on the turbo because I had noticed that the new one had a smaller gap for the air coming off the compressor wheel (see pictures below). Interestingly it seemed to help the problem, but it is definitely still there. So I'm not sure what the problem is. I'm going to try some data logging with Car Code and try to see what the differences are in the fuel and timing between when it's pulling strongest and when I'm at full throttle so I can talk to Bill some more. I still feel like it's a tune issue, but I don't have the info to back it up. Otherwise I really like the tune, it pulls really nicely at all throttle positions other than full throttle.
HX40 Comp Gap.jpg JM HX40 Comp Gap.jpg
 
I do have another update. I was noticing that I had engine vibrations while driving down the road. With all of my other shaking problems I was feeling more and more that I had motor mount issues. So I bought the Energy Suspension inserts. I had purchased some new cheap motor mounts when I was buying parts for the Optimizer, but then found out they don't last long. So I gutted those and put the ES inserts in instead of the rubber. It took me just under 3 hours to swap the mounts, which I guess isn't too bad, but considering I could have done it in 5 minutes when the engine is out....it kind of disgusts me.

Anyhow, the moral of the story is that it's definitely smoother now!! I don't feel engine vibrations going down the road and it's much smoother at idle. I can still feel the engine at idle, but it's not obnoxious. All this time chasing this problem and it was intake tract and motor mounts. Ugh.

I hope somebody else doesn't make the same mistake I did. I thought my factory mounts were ok when I looked at them in the chassis, but apparently I didn't know what I was looking for. Once removed they are clearly bad. I was tired of spending money on the project, and I was afraid the ES mounts would be a little harsh so I thought I was making a smart move leaving the stock mounts in....the truck only has 144,000 miles on it so it's relatively low and I thought I was going to be ok on the factory mounts - NOPE. So I won't make that mistake again.

Little by little I'm getting this thing dialed in.....
Mount old1.jpg Mount old2.jpg Mount new1.jpg Mount new2.jpg Mount new3.jpg
 
n8in8or said:
I've found that I actually have LESS power at full throttle than I do at 3/4 throttle!. . . I called Bill Heath and talked to him about an hour regarding this. He looked at my tune while we were on the phone and he didn't see anything wrong with it. . . .
Click to expand...


Try swapping ECM's with a different tuner's tune.


I was told that my twitchy throttle coming off-idle was the something in truck and not the tune. Truck got a new motor & tranny and still had a twitchy throttle.

Swapped ECM's with a different tuner's tune and the twitchy throttle disappeared.

Ok sure, it is possible that was the physical ECM, but I have not bothered to pay for yet another tune to find out.


n8in8or said:
So I bought the Energy Suspension inserts. . . . it's definitely smoother now!!
Click to expand...

In case your motor now makes a 'thunk' at shutdown, this will go away.
 
Power up top could be that the fuel is tapered 'being pulled' by the program I think someone had mentioned that in relation to max rpm.

At 2.0 pressure ratio (29.4 actual & 14.7 @ boost gauge) your pumping lots of air probably 35/40 lbs with that compressor which is enough to feed 350 to 400 hp when calculated @ 10 hp per lb of air so perhaps there is not enough fuel.
 
I had mentioned the mounts awhile back.........

You can datalog what is happening @ WOT you will see right away of its fuel related or maybe IAT too high w/o CAC/IC I suspect that..

The compressor housings surely have different CFM capacities but the only compressors we have to compare to are Holsets if the the info is even in the public domain.
 
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JayTheCPA said:
Try swapping ECM's with a different tuner's tune.


I was told that my twitchy throttle coming off-idle was the something in truck and not the tune. Truck got a new motor & tranny and still had a twitchy throttle.

Swapped ECM's with a different tuner's tune and the twitchy throttle disappeared.

Ok sure, it is possible that was the physical ECM, but I have not bothered to pay for yet another tune to find out.




In case your motor now makes a 'thunk' at shutdown, this will go away.
Click to expand...

I tried my other Heath tune (just a straight Max-e-Tork tune) and the problem does go away. However that one isn't as strong at 3/4 throttle as the new tune is. My gut feel is the tune needs to be adjusted at full throttle, but since I've already talked to Bill about this problem I want to come back to him with some hard data to prove it.

Good to know on the mounts. Yeah it does do that...I was wondering if the mounts would "break in". In fact it has always done that since I've owned it and that was likely the bad old mounts all along.
 
FellowTraveler said:
Power up top could be that the fuel is tapered 'being pulled' by the program I think someone had mentioned that in relation to max rpm.

At 2.0 pressure ratio (29.4 actual & 14.7 @ boost gauge) your pumping lots of air probably 35/40 lbs with that compressor which is enough to feed 350 to 400 hp when calculated @ 10 hp per lb of air so perhaps there is not enough fuel.
Click to expand...

When I talked to Bill, he said that it wasn't tapered up top when he was looking at my tune, but we'll see what it shows on Car Code.

FellowTraveler said:
I had mentioned the mounts awhile back.........

You can datalog what is happening @ WOT you will see right away of its fuel related or maybe IAT too high w/o CAC/IC I suspect that..
Click to expand...

Yeah I remember that...Turbovanman did too. I wish I had listened to you guys sooner :(

I don't feel like it's an IAT problem....the power output changes as fast as I move the throttle pedal - at 3/4-ish throttle it's pulling nicely then as soon as I floor it the power drops some, and again as soon as I drop the pedal back to 3/4-ish the power picks back up. It seems tune related, but I've been wrong before (reference motor mounts for one, ha).
 
n8in8or said:
When I talked to Bill, he said that it wasn't tapered up top when he was looking at my tune, but we'll see what it shows on Car Code.



Yeah I remember that...Turbovanman did too. I wish I had listened to you guys sooner :(

I don't feel like it's an IAT problem....the power output changes as fast as I move the throttle pedal - at 3/4-ish throttle it's pulling nicely then as soon as I floor it the power drops some, and again as soon as I drop the pedal back to 3/4-ish the power picks back up. It seems tune related, but I've been wrong before (reference motor mounts for one, ha).
Click to expand...

IAT limits 50 to 194 deg f what is your data logger showing?
If you're at max fuel @ WOT then perhaps there is need for more fuel beyond what the DS4 can put out in relation to compressor pressure ratio a DB bull moose maybe needed.
 
FellowTraveler said:
IAT limits 50 to 194 deg f what is your data logger showing?
If you're at max fuel @ WOT then perhaps there is need for more fuel beyond what the DS4 can put out in relation to compressor pressure ratio a DB bull moose maybe needed.
Click to expand...
I don't know what the IAT is yet, but I will be sure to note it when I do the datalogging. I tried datalogging once but it didn't work. I think I know what I did wrong, but I haven't tried it again yet.
 
n8in8or said:
I don't know what the IAT is yet, but I will be sure to note it when I do the datalogging. I tried datalogging once but it didn't work. I think I know what I did wrong, but I haven't tried it again yet.
Click to expand...

When you open carcode "data" screen make sure it connects the IAT will show towards bottom of that screen.
 
Do not recall if Evans was put in the motor. If it was, consider getting the ECT's (as measured by the ECM's sending unit) while data logging and see if they are considerably cooler than the dash gauge.
 
JayTheCPA said:
Do not recall if Evans was put in the motor. If it was, consider getting the ECT's (as measured by the ECM's sending unit) while data logging and see if they are considerably cooler than the dash gauge.
Click to expand...
I put Rotella Ultra ELC in it. When I was doing the TDCO Relearn the readings were pretty much what the gauge was reading, but that was always just idling in my barn. I'll see what the temps do.
 
JayTheCPA said:
Do not recall if Evans was put in the motor. If it was, consider getting the ECT's (as measured by the ECM's sending unit) while data logging and see if they are considerably cooler than the dash gauge.
Click to expand...

I noticed via handheld temp sensor more even & stable temps across my 6.5td after the EVANS coolant install. I am borderline with radiator core size of 1" x 2 and considering a thicker core setup of 1.25" to 1.50" x 2.

Will know more after I get the thick core Ram Cummins CAC/IC installed and relocate the aux p/s, trans and crankcase oil coolers.
 
n8in8or said:
When I was doing the TDCO Relearn the [ECM - ECT temperature] readings were pretty much what the gauge was reading, but that was always just idling in my barn.
Click to expand...

FellowTraveler said:
I noticed via handheld temp sensor more even & stable temps across my 6.5td after the EVANS coolant install.
Click to expand...

Recommend to get ECT readings while running (as measured by the ECM).

At idle / stand-still, my dash gauge and ECM get close. When running empty, the ECM goes down and lately is ranging from the 150's to 170's while the dash shows a constant ~187.
 
JayTheCPA said:
Recommend to get ECT readings while running (as measured by the ECM).

At idle / stand-still, my dash gauge and ECM get close. When running empty, the ECM goes down and lately is ranging from the 150's to 170's while the dash shows a constant ~187.
Click to expand...
That's interesting....I'll check it out and report back.
 
JayTheCPA said:
Recommend to get ECT readings while running (as measured by the ECM).

At idle / stand-still, my dash gauge and ECM get close. When running empty, the ECM goes down and lately is ranging from the 150's to 170's while the dash shows a constant ~187.
Click to expand...
I'll pay some attention to this.
 
Ok, I took a quick video during lunch with my handheld OTC scanner. It only shows a couple things but I was curious what IAT and ECT were doing. It was 76*F with 60% humidity and rain while I filmed this. Yes, my IATs are getting over 200*F when I get on it for a bit. I'm not sure if that is contributing to anything or not, but I did still have the full throttle issue when my IATs were below 195, in fact you can hear me pedaling it some of the time because I'm playing around with the throttle position. I should take a video of my foot so you can hear the difference in the engine at the different positions. Anyway, I don't think this will show much, just something to share.

 
Oh and yes, I did notice a discrepancy between the dash gauge and the ECMs ECT reading. As much as 15*F sometimes. I'm not sure which is more important though to be honest.....since I'm assuming the temp in the crossover is the ECM temp and the temp in the cylinder head is the gauge temp. Is that right?
 
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