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Why do I still not have power????

commander502

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Bixby, OK
So my 95 k2500 6.5 doesn't have much power. I can't even power brake it. It has 33" tires, 3.73 positrac, 4l80, Hx40 turbo, bosche injectors, pmd in bumper, new injection pump, lift pump works. I'm sure I'm forgetting some stuff, but with as much as I've done to it, I'd at least expect it to break the tires loose. Any thoughts?
 
Fill out your signature so we can see what you have. If it did break a year ago, what have you changed since then? Tires? Turbo?

i also don't see a chip listed; I doubt you are spinning your tires with a stock chip.
 
It was completely stock and ran like a champ. I spun a bearing and had a new engine installed. Never been the same since. Can a chip really make that big of a difference? If so, I was thinking ssdiesel for a tune.
 
Ssdiesel is meh. Better to call up slim shady or Leroy diesel. (Burning Oil) Really.

You have a much different turbo map than what Walt's (ssdiesel) tunes are for. Trust me; I know the guy who makes them for Walt.

Also willing to bet your timing is off.

when your tires last spun, were they 33"? And did you have the HX40 on there, with a stock tune?
 
The tires last spun fully stock. We had power problems after we got the new engine installed. Took it to a shop and they fixed some wiring. (Didn't seem to help) Had 31s last time, and did all my upgrades with the same tires before I got my 33s. Seemed to have as much trouble with the 31s as it does with 33s. I know for a fact that the injection pump timing is spot on.
 
Hmm. Timing is tricky to set on these, if the mech isn't familiar with them. That's why I asked. You should gave had the same performance with the new engine, if settings the same.

the hx40 won't spool properly with stock chip. Hard to get it to brake stand and light off without more fuel.

advise trying a tune
 
That was SOOO helpful. The thing is, it would break em loose no problem about a year ago, so could anyone give me some actual help?

Actually he's not kidding! You seriously need to re-consider the econo diesel MPG platform engine your working with and the turbo changes you made. Quite frankly it is cheaper and far more rewarding to use a gas guzzling 454 or modern, more HP and TQ than most know what to do with, diesel to just smoke the tires. This is immature wasteful stuff to most people on this 6.x platform as most would make a frugal person appear to be careless with their money. :rolleyes5:

The factory tune and SSdiesel tunes don't have a clue how to use the better turbo. There are several other better tunes out there that have been tried and tested with aftermarket turbo's.

A day at the dyno or track is a better way to measure your power and changes made to your power from upgrades, turbo's etc. Because after the giggles of the tires breaking loose the POS GM turbo is done now being a power sucking restriction and your HX40 is running it over in the higher RPM. You now have power in the higher RPM because you traded off the low RPM power with a bigger turbo. With an automatic and this High Speed Diesel engine you have useable power in the upper RPM with the better turbo and that is where the automatic transmission wants to put the engine for power. In other words quit thinking you can lug the engine with tire smoking low end and enjoy the power in the upper RPM when the turbo comes to life. Rather than lug and then roll over and struggle to get to redline and the next shift like the GM turbo did.

It's possible you have other lingering issues like a plugged converter, restriction in the intake like a fender snorkel, plugged air filter, timing off... It would be useful to know if the turbo was put on with the 'new' engine and when the taller tires were put on.

A 4.10 rear end or lower esp with the tall tires would be a start. $500+
A high stall triple disc converter, Yank will make one for $1000.

Beat up 454 tire smoker pickup $1500. Won't get double digit MPG ever. The 6.5 is good for ~14 MPG.

And $1500 for a 454 is likely what 'Big T' was thinking...

Edit:
Some questions answered while I was typing.
Did you put a 4" exhaust on the thing?
And No, breaking tires loose with a larger turbo is harder to do without a lot of smoke from the exhaust. My 1993 would start to break the rear tires loose with 4.10's stock. It doesn't do it with a larger ATT turbo. But it pulls like a raped ape all the way to the top end RPM where the IP cuts down the fuel to save the engine from overspeed.
 
This truck is my dd. The reason I changed the turbo was the gm4's bearings went out. The timing was set by the only mechanic I could find that knew the 6.5s. I couldn't afford a gas trucks mpg, and I sure as hell can't afford a Duramax. I've sank so much money into this truck, I just want it to run good. So the best bet would be a tune? Not wanting to run down a cummins, just keep up with it.
 
So I guess I never got a chance to see the "stock performance". When we got the engine installed the turbo was bad, along with bad injectors.
 
If you want to do one single mod just to lay patches on the road, yank the 4L80E and drop in a NV4500. Actually, make that two mods as changing the tranny will need a re-tune of the chip. Bonus is that you can then try to convince your insurance company that you have a new theft deterrent system seeing as nobody knows how to drive a stick anymore :hihi:

Oh, wait . . . Was I supposed to make a *helpful* suggestion . . .???? :D
 
That was SOOO helpful. The thing is, it would break em loose no problem about a year ago, so could anyone give me some actual help?

Well, the way you wrote your original post, what did you expect. The additional information about the before condition vs after condition sheds more light on the situation, but still not enough.
 
Thanks Josh. A lot of what you posted was imbedded in my snarky cryptic message. If I might add to that, the OP has a desire to "spin" his wheels, then goes on to say that he can't afford the mods, nor a 454 gasser, because this is his daily driver. A fatter wallet might fix that, but it's not often you can have it all in one package. I guess it's an age thing.
 
OK, you went from a stock engine/turbo that spools off idle and makes it's power below 2500 to a turbo that doesn't really spool up until 2000 or so. Of course your going to lose bottem end. Turbo swaps is a trade off. You gain top end, but lose bottom end. Also without knowing if your timing is set correctly, theres no way of knowing if your current engine is performing to it's potential. And are you running a 3 bar map or boost fooler to keep from coding? The HX40 is capable of making boost well outside of the 10-12 PSI that a stock tune defuels and shuts down at. A stock exhaust even with no cat is going to be CHOKING your HX40 turbo. You have alot of things working against you, and this is why having your sig filled out helps to tell us what you have at a glance. You need to MATCH your combo, not just throw a couple of performance parts at it, and expecting better power. Your stock exhaust without cat isn't going to compliment your HX40 turbo, the stock tune isn't going to spool it properly, and is probably defuleing when it does finally light off, and your timing could be way off without it coding. You must have either a TECH 1, TECH 1A, TECH 2 with OBD1 adapter, or GMTD scan tech to set the timing on a 94-95 truck. And with the range of timing that an OBD1 will allow without coding, setting your timing could be of a HUGE benefit. Just because it was set to not code and run, doesn't mean it's set for power.

Verify your timing is correct FIRST, then match your combo to work and you will pick up alot of performance. It may not break the tires loose from an idel, but once the turbo lights off you should see a night and day difference. Until you match your setup, you can expect LESS than stock performance from it.
 
The first questions I asked were trying to discover a timeline of events. In what order do the following things happen?

a- tires break loose
b- timing is set to -1.94 using a Tech-2 and correct procedure
c- 31" tires exchanged for 33" tires
d- GM-4 exchanged for HX-40
e- new motor installed
f- tires won't break loose
g- new injectors installed
h- miscellaneous other things done?
 
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