kbracing96

iTrader: (26)

So about a week ago, I was wanting to see what I could get out of the mostly stock 4.8 in my truck with the E85, I must have got a little to greedy a little to fast. Was running really good at 11psi and 23.5* of time with no kr at all, but the 43lbs injectors where MAXED. So I put in the set of 60 I had and though I would bump it up to 14 lbs and see how it ran. Also added a second M15 meth nozzle and was really rich. Went to make a couple of tuning runs to dial in the AFR (pig rich, around 6:1 when should have been around 7-7.2) and got back to the house and it had pushed some coolant out the over-flow on the rad fill tank.

SO I turned it back down to 7 lbs and took it back out, and no coolant pushing, then 10lbs and seemed ok, so I thought I'd leave it there. And the saga continues as my meth pump dies on me 2 days later, lol. So I dial the tune in with out meth to 11 psi and 22.5* of timing and so far wasn't pushing any more coolant. I though I'd hit the dyno real quick to see where it was at on Friday before heading to the track and it made 513/500. Not bad since it was about 1/2 lbs of boost less and was hotter then last time.

Took it out to the track and got one run in, 12.72@107.5 with a 2.0 60', but it lifted the heads and pushed a bunch of coolant out so that was the end of that. Motor still runs fine on low boost and doesn't get hot so I think I will be able to drive it for a bit, but thing are in motion for a forged 5.7

I really thought the motor would take more then this, but I think the combination of the super rich E85, high boost and high timing was just too much cylinder pressure for the heads to hold down. I though I would have tranny problems before motor problem, oh well, on to bigger and better things

Here is the track vid

7845

iTrader: (1)

so do you think if you kept the E85 and meth working properly and tuned right that it could of lived longer and made good numbers? how did the SOTP feel when running like this? wonder if E85 is way to go with gas prices over 4 dolalrs

kbracing96

iTrader: (26)

I still like E85 for a cheep race gas, as I never had any problems with KR. I was always overly rich just got too high of cylinder pressure for stock gaskets and bolts. But I figured it out the other day and with the mileage difference, I get 10.5 on E-85 (3.08 a gal) and 14+ on gas (3.72 a gal for prem), so it cost me about 5 cents more per mile to run E85.

I really like the way it runs on E85, feels much stronger around town, but not worth the extra money for me right now since I have to drive 38 mile round trip to get it.

7845

iTrader: (1)

yea i noticed that with the non HP appications. the mileage vs price cancels out... but sheesh at over 4 bucks agallon its hard to not consider. Sheets are starting to pop everywhere and seems to be only place that has it. deffently a consideration

bud8fan

iTrader: (9)

wow...guess you found the limit of the head gaskets kyle....very good info thou...

7845

iTrader: (1)

so what wa duty cycle with the 60s and e85

XLR8NSS

iTrader: (4)

Maybe cut back on the timing some and just up the boost the next time.

kbracing96

iTrader: (26)

Well that's the other thing, the single 255 pump is out of steam too. At 6200 it starts to lean out a little, even when i command more fuel it just increases dc, but doesn't increase the afr. They are around 92-94% but thats all the pump can flow.

That might have been better looking back,

trever1t

iTrader: (14)

wow, sounds like you escaped without catastrophic damage luckily.

KySilverado

iTrader: (7)

Damn. The 4.8 that could. Don't know that I have read about anybody lifting the heads on a 4.8. Guess its because nobody attempts to push the little 4.8 to far