im running a 2.7 on the tvs with 7 gph meth nozzle, i used to be able to run 22-23 timing into it on top end before i did an engine rebuild, now im knocking at 19, ive knocked it all the way down to 18 which is way to low for meth, the only other thing i can think is i got a bad tank of gas. What ar others able to run for top end timing with a 2.7 pulley on the tvs.

whats also weird is i can do a 2nd gear pull and it will not knock, then do a 3rd gear and same cells detect knock

 

I was pulling 25* and running E85. Most cars I know can hold 23-24 easy on any setup with methanol or E85

 

Bad tank of gas, iat2s or tune is ****

 

Yah I'm really thinking it was bad gas as I hadno issues before and my maf is dialed in and timing map is smooth as it gets, unless I got crap methanol it is the bottom of my last jug. Iat 2 are low as well

 

Yeah could be the meth or gas. .. Hopefuly its not a ringland if it dont go away by the fill up after next and same with meth do a compression test

 

brand new pistons, and i just did a compression test to verify and got good compression

 

Did you check to make sure the meth pump is operating at full pressure?

 

Yah I thought of that today and did a check and I'm getting good flow and spray

 

Only 22-23*? I've got 28* on a 2.7 and E85, no meth.

I was going to suggest checking the meth, make sure it's working. Since you said it was, I'd wait it out for a tank or two and see what happens.

 

yah, its pissing me off, ive posted tune and log on hp tuners forum if people want to take a look, upper maf is not dialed in but is hard when it keeps knocking when trying to dial it in

 

I love posts like this!



Are you running the same CR on your new pistons?

 

it would think that it would knock in 3rd more than 2nd because its putting more load on the engine


this

 

yes, but i bought them from someone else that said they ordered 9-5 cr(brand new never installed), if they were 10-1 that would explain the issues

yah thats what i figured as well but with 100 %meth and knock at 6400rpm when it only calling for 18 timing it doestn make sense