Sooo I have a 2000 Silverado ECSB with K&N intake, doug Thorley long tubes with NO cats, and flowmaster dual side exit. Iridium plugs and msd 8.5 wires with blackbear 91 tune.. Truck runs great and I hit 9.7 @ 76mph at IRWINDALE in the 1/8. Is it worth the switch to e85? I have a station locally and would love to run it.. Justin @ BBP said it would be a great option but not absolutely necessary at my 8:8.1 compression ratio..

Any ideas on what I should do?

Thanks!

 

no.

you don't have a wideband to know how far off your mixture is going.
your comp is to low to take advantage of it.
you don't self tune to be able to push timing.
your stock fuel system doesn't flow nearly enough to maintain the correct mixture even if you had the above three taken care of.

Spend money else where.

 

Why the 8.8-1 comp?

 

word with the comp i have seen this come up before... I thought the lowest comp in any stock LS engine is 9:6:1, like I think my 4.8 has

 

From doing research on the L20 4.8 it's at 8.8:1. Which kinda sucks.. I've thought about doing a top end rebuild (145,000 miles so far) and doing rings, new .04 cometic head gasket and fly cutting the heads .04.. I have a good head guy we use for the Volkswagens (Performance Technology) and gives me a smokin deal.. To try and get the cr up to about 11:1 and possibly do a comp 220/220 cam or maybe 212/218?

 

4.8 is 9.5:1 like all the other motors

 

don't waste time building up a 4.8 for NA application.
Use that cash to get a 6.0 long block and bolt that bad boy in.

 

trapping 76 is damn good for a 4.8 excab

 

With stock compression I don't see E85 helping at all. I wouldn't.

 

An L20 is a 4.8 from a 2010-2014 application. It did indeed have 8.8:1 if some one swapped it in, But why???

If its a stock LR4 which was used from 99-07 classic in these trucks it would be a 9.5:1