camd01silv

Now on to the next problem... The thing has developed a nasty miss. Thought it might have been plugs or wires, so I replaced them, and it got worse. Before I tore into it, we were driving it a little and I noticed a little miss, but it seemed to go away once the truck was warmed up. Now that the cam is squared up and new plugs are in, it will barely rev past 1500 if you hold the gas and brakes because its missing so bad. I know it'll need a retune because of the cam and new turbo, but jeez I didn't think it would be this bad. Haven't done a comp test yet, going to do that tomorrow. Hopefully driving it around with the cam a tooth off didn't bend a valve or something... DAMN HOT RODS!! LoL

fastnblu

iTrader: (2)

I need to find this thread I think. For some laughs but sometimes u learn from others mistakes. In process, helps others who follow after.

Ok, so u found problem. But before u could see what smaller turbo did, u changed it... so u'll never know.

camd01silv

Yeah but that's ok. The turbo I put on has much more potential.

In other news, I finally got to drive the truck yesterday... Drives just fine until it starts to build boost, then it starts spittin sputterin poppin bangin... No misfire tho, which made me feel better. Should be fun once it gets a good tune.

boostedsl2

What us your timing and af? I made 340 whp on 6 psi only to find my buddy had me at like 12 degrees lol.

Cranked it up to 12 psi and put it at 19 degrees on 93. No knock and tge old butt dyno said I picked up a lot of power. You can really run out the timing quiet a bit on e85. Significantly more than pump. Rule of thumb in my world is 18 degrees at 18 psi. Maybe a little aggressive but you get the idea.

I've seen gobs of power (100+) on the dyo with a good tuner due really conservative tuning by a previous shop.

Af is worth a lot of Power too.

Your mistake isn't that bad. I installed a clutch disk wrong once lol. I also had a rag cover the whole side of an intercooler. That one was fun to figure out haha

camd01silv

Well I got a call from the tuner today. With the cam timing squared up, freshly cleaned injectors, and the air/fuel ratio set to an uncomfortable-for-forced-induction 13-13.5:1, as well as a jump in boost pressure from 15psi to 17psi, the truck made an even more disappointing 450-ish rwhp. So, with cam timing set dot to dot, the injectors cleaned, boost pressure up, and fuel mixture leaned way out, we lost 50-60rwhp. This is really pissing me off. Could the cam be ground wrong? I've heard if this but never had it happen to me. I'm at a loss as to what the **** is going on. Please someone help.

oakley6575

iTrader: (5)

Why would you tune it to 13.5:1? It's not going to make power there

camd01silv

Tuner said that setting it that lean was the only way it would make a clean run on the dyno. Any richer and it would start cutting out. I thought that maybe the rockers had loosened off... That happened the first couple cam swaps I did. Never checked rockers on this swap after a few heat cycles.

I guess I really need to bite the bullet and buy some tuning software and do it myself...

FFDP

iTrader: (2)

What kind of tuner would say that, doesnt he understand how dangerous a lean condition could be if you are making alot of power.

To me it seems that he isnt very well skilled, but I can't be for sure.

oakley6575

iTrader: (5)

Who is the quack doing the tuning? I wouldn't trust him with your truck anymore. Anyone who leans it out to that extent while in boost "to make a clean run" is not a tuner. Obviously there is an issue somewhere if it won't pull clean. Instead of putting your truck in a dangerous position to get a horsepower number, he should have tuned it correctly and figured out what was happening.

Sorry to be blunt but that is pretty shitty he would do that to someone else's vehicle

GMCtrk

iTrader: (27)

Holy ****. That is downright scary.

Your problem sounds like too large of a spark plug gap. Close it down to .025 and get the afr in the 11s and see how it does.