Need some help new Combo not performing

R

rayjon

Venimus, Vidimus, Deus vi
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May 30, 2008
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I've just finished a 12v swap into a Chevy the truck is used mainly for work and towing. The doner was a 95 175hp truck cpl 1550. It is running a he351 with the waste gate moded and a #6 plate with stock injectors an some 3k governer springs. Given the truck weighs 8500lbs. It is still lazy. I am getting 30lbs of boost and it spools quick. Fuel pressure is good no issues runs smooth. I was hoping to keep the small injectors for mpg and lower egt when loaded heavy. But I may need to do some 215 or 5x12's to wake this thing up some...

Any ideas other than injectors , im going to check the timing this week.
 
What are your egts? Any smoke, and what color is the smoke? What is your timing at?
 
buckle the gate down a bit or put in a manual boost controller, if your egts are a bit hot. i bet they arent though
 
will double check when I get home out of town now.. the plate dont think its full forward if I remember we put it in the middle plus a little...

fuel pressure runs 24 at idle and about 14 under load, has a tork tech ofv in it.. running a stock pump with the gm 6.5 pump as a pusher.. (may want to take that out or replace it with something bigger)

a little black on spool up then it clears up no smoke on the top..

egts are low most I can get right now is about 800 pre turbo but I cant really load it down hard either.. need to take a run up the hill with a loaded trailer...

havent gotten to the timing yet stock should be 14.5 I will bump it when I check it to 17-18
 
^^^ What he said. Like alot! A new factory lift pump will have between 35 and 45 psi. You are low on fuel pressure. Bump timing.
 
More fuel pressure. More agressive plate and/or move it full forward. Theres more free power to be had out of the plate before you need to spend money on injectors.
 
I have a new pump in it with a ofv, didn't know the stock pump would put out 35 to 40 psi, I will look at the supply lines and figure out why it isn't... Thanks , thought I needed a pusher to get that much...

I will be home tomorrow and have Tuesday to work on it.. plan on fixing the fuel first.. moving the plate and then bumping the timing,

given I only have 20lbs of fuel I think I found my problem, time to pull the sender and get rid of the gm pusher pump....I already eliminated the fuel heater, new filter and pump last week.
 
I think a #6 plate was what I used at that level? you could try to score one used, or grind yours into a #100 plate. Sounds like you arent making much fuel up top. Not sure how far forward that plate is.
I had the stock LP with 25-35psi and it still made 410 on the dyno. so long as it doesnt go real low at WOT, Id guess thats ok.
 
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The #6 looks pretty agressive up top, just backed off on the bottom end. But either way I would still take it to a #100 and move it FF.
 
Well figured out the gm 6.5 lift pump is only rated for 30gal per hour and was causing a restriction. And the plate. Forward more helped, still have to pull the sending unit and check the filter on the bottom but the fuel pressure is better. Anyone found a stock type lift pump I could replace the gm one with to feed the cummins lift pump. Don't need a fass or air dog as I don't plan on major hp just want to help the stock list pump as my tank is at the rear and with a crew cab and 10ft bed it's a long ways at least 16-17 ft.... From the tank to the pump.
 
1.) Is your afc all the way forward?

2.) Have you done the afc mods? (If you're not sure, the answer is no.)
 
afc is full forward and not modded, wanted to get it base lined and working right before I started playing with that.. getting there made sure the run solenoid was the correct distance and eliminated the gm pump today.

Then it decided to rain and drop 20 deg, 45 degrees in Reno in June... is dam cold... it was 101 in Elko yesterday... and this beast doesn't fit in the shop... so I quit...will try some more tomorrow. want to clean the pickup in the tank and then recheck the fuel pressure under load...

thanks to everyone for the help. have been searching and learning for a couple of weeks on different stuff, just needed some help...
 
A truck with an un-modded afc will be relatively lazy in comparison. :kick:
 
I will get there..:kick:. it still has the stock clutch and I want to get it running good before I start adding fuel..

this motor sat for a while as the 6.5 didn't want to die, had blowby but kept running.. just want to get some miles on the 5.9 and make sure everything is ok before I throw fuel and hp to it..

plan is to swap a 14" clutch and a fuller once I get it all running good. then I will add some serious HP.. :rockwoot:

I dont want to do what I did to my dodge and have to start fixing drivelines and rearends due to alot of HP, i want the drivetrain to go with before I throw alot Hp at it.. I tow alot and a cummins will shred a nv4500 and 1410 u joints.. with a big trailer behind it... been there done that.. :doh::doh:

BTW is that your toy in your avatar, I have a few land cruisers.. its a bad habit..
 
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