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What do I need to do on a rebuild to get a 6.5L to live at full throttle towing?

He had Heath High Output injectors and an ATT and was enjoying it, but went back to stock turbo injectors and the GM8 when the propane took them out.

What Buddy said!

Three of the marine injectors were not spraying, just squirting at 1,200, the tips were burnt. The other 5 were popping at around 1,500. The ATT made a big difference in performance but when used with the bad injectors something didn't feel right.

With all the fuel going in and easing into the throttle I had 2 big black clouds of fuel coming out the duals. Now hit the throttle hard and the thing would down shift, smoke is gone, and the ATT would spool up and the thing would take off very strong.

But with the stock injectors and the GM-8 I do feel as if I have lost 100 horsepower. But I still have the WMI and Propane injection. And it does get good milage, so far!

I know I have lost a lot of power because I can't power brake this engine anymore and get those big 265x19.5's duals spinning on black top and laying 4strips of rubber!!

635
 
The emissions test here is a smoke test. Floor it in neutral and hold it on the governor till we get a reading... :mad2: I will check the trans stuff out.


Just back it back out to like 2800rpm for the test, so it aint revving 35-3600rpm with no load on the engine. Its easy to get to.
 
I know I have lost a lot of power because I can't power brake this engine anymore and get those big 265x19.5's duals spinning on black top and laying 4strips of rubber!!

635

Intersting note, buddy mentioned in another post he could spin em with the GM-X and NOT the ATT.
 
Probably has more to do with the loss of the larger amount of fuel and having the turbomaster turned down to 15 pounds of boost from 23. But the ATT would set you back in the seat a lot more when it shifted. You could feel a lot more power was available.
 
Intersting note, buddy mentioned in another post he could spin em with the GM-X and NOT the ATT.

Small turbo = quick low end boost. Chokes up high (RPM)
Big turbo = no low end boost. Kicks on with high load but low restriction - will not choke. (Choke here is referring to the exhaust not overspeed.)

It is all a trade off.
 
635 also has some nice engine work that assists creating power faster with better air and exhaust flow; thats some stuff I'd like to do someday if the cost goes down. I have 3.42 gears and a few inch taller tires than stock, so spinning them is difficult, unless I brake torque it. I also have the smaller precups still.
 
Small turbo = quick low end boost. Chokes up high (RPM)
Big turbo = no low end boost. Kicks on with high load but low restriction - will not choke. (Choke here is referring to the exhaust not overspeed.)

It is all a trade off.

Aye, but by changing turbo's BACK to the GM-X Buddy reports he COULD spin the tires, (makes sense, quick low end boost), but 635 stated he only could do that with the ATT.

Rough Statement, alot is in play here..

4 tires vs 2, unsprung weight, 635 could have been visualizing running onver Ian and power braking it to 3k RPM!!!)

I really can't wait for the ATT. I live around some really nasty hills, and my engine is ALWAYS loaded....

After driving around with TM no chip, I don't push over 9 boost up hills. I have to feather the pedal up highway grades for it not easily go over 9 lbs... I just don't want to code (can't stand SES lights :) ... I know I'll reap every last benefit out of that ATT. Matt wants that 'Feel Good Feeling' Buddy described!

Even heavy as I am, with the 4:10 gears, she' s always super peppy at low speeds anyhow, so If I loose a touch of that (always a tradeoff as you said), Thats quite alright.
 
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