Flapjack

We installed a ProCharger D1SC in a buddy's truck a few months back, but the tuner hasn't been able to figure out what is causing the hard starting he's experiencing.

He's using FAST 65lb injectors. They were a little too small, but we were able to get them to work with a set of aluminum spacers.

I'm guessing it has something to do with the injector values, but I'm still not sure. I was hoping someone here has seen the problem. Basically, the truck takes several seconds to turn over. It sounds terrible. Once in a blue moon, it'll start right up... but that is very rare.

Old Geezer

iTrader: (3)

NE data logs made?
Post the tune.

"It sounds terrible"..........As in?????
If the tuner can't modify the inj info, find another who can.
With the "info" you have posted so far, there's little help to be given...

Flapjack

He paid for the tune, so he doesn't have the tune. We can see if he can get it. I'm pretty sure the tuner used LS1 edit. My friend has a Diablo Trinity that he used back when the truck was N/A. What should he log? Is anything actually being logged that early in starting?

As for sounding terrible, it sounds like it's an old flooded carb or something. cranks for 4-5 seconds before starting... sometimes longer.

BLK02WS6

iTrader: (2)

What does injectors were a little too small, but we were able to get them to work with a set of aluminum spacers mean? And, it sounds like you need another tuner...

ATEURZO6

im lost on the spacer part????? sounds like you need a differant tuner ... Cars never leave untill the problem is figured out or the tune is right!!! End of story
Ls1 edit do people still use that??? lol jkn...

Try and get a log or the tune file and post it .. Im sure one of us can get you on the right track!

Flapjack

So... when we were trying to find the injectors, we got two different heights. It really seemed to depend on who we talked to, but we kept getting different specs. We eventually called GM to get the stock replacement part number, then looked up the specs on that, then ordered the injectors based on the height. They also looked similar to the stock ones in the truck (we didn't pull them out, though). At any rate, despite all that fuss, they were still too short. The aluminum spacers are roughly an inch long. They pop onto the bottom of the injectors to add length. My Mustang was down for the count, so we robbed them from my 105s (as the are short too) and he replaced them later. Here's a picture of them.

Try and get a log or the tune file and post it .. Im sure one of us can get you on the right track![/QUOTE]
Yeah, that may be exactly what he ends up doing. He's not too worried about it, but it has got to be killing the starter. At the very least, it's a bit embarrassing. The truck is an absolute monster, though!

BLK02WS6

iTrader: (2)

I would say those spacers are your problem... you can't pull the injector up out of the hole and expect it to spray the same... put the proper injectors in it and I bet it starts correctly.

ATEURZO6

we have all run into that car or truck that shouldve been a pretty striaght foward tune ... but turns out to be a PITA lol just try and post a log and tune file

ATEURZO6

and imo those spacers look like they would be used to convert from short style to long style ... ive heard in the past that those spacers effect the atomization of the fuel spray.. what is your intake and fuel rail set up?

Flapjack

I used to think that way, too... but I've also had zero problems running them myself (albeit in a Mustang). Even Jarad at Lethal Performance has said that the spacers do not make any appreciable difference. Besides, everything else is spot on when the truck is running. It is otherwise perfectly tuned. I'm pretty familiar with the cold start tables in the Ford PCM... but have never tuned a GM myself (which is why we brought it to a GM-based performance shop). The guy has a great reputation, so I'm stumped as to why he would've stumbled on what should be a pretty simple tune. Maybe it is the spacers. Maybe we should try moving them to the top of the injector instead, if that's not where they already are. Actually, now that I think about it, I'm pretty sure they are on the top of the injector. I'll have my friend check.

**EDIT**
The spacers are on the top. Nothing but straight fuel pressure up there.

He's working on it. We've been slammed at work the past few days, so have had no time to get ahold of the tuner and ask. I'll see if I can get it tomorrow.

They are used to convert short to long style, as despite all our careful research, we STILL got the wrong size injectors. The intake and fuel rail are stock. The injectors were the only part of the fuel system that was changed.