unioncarpenter84

iTrader: (22)

got a lt1 heres the specs the problem is tht im getting some engine knock pcm for less decesotized my knock sensor still getting some knock

whats the advantages and disadvantages of 100 octane

will the 100 octance fuel help???

Lt1 350 bored to a 355
Heads ported and polished (flows: intake 278, exhaust 197)
CC Cam 230/242, .510 lift,113 lobe separation
Comp Cams Pro Magnum 1.6 roller rockers w/7/16" studs
Comp Cams 987 Dual Valve Springs
SI Silverline Series Valves,(2.00" intake and 1.57 Exhaust)
Eagle H beem connecting rods
JE Forged Nitrous Pistons
Crane Hardened Push Rods

noice

Yea it will help, I ran 104 octane since they sell it at a pump near me. The problem with doing that is that you aren't finding out the problem, your're just masking it. I found I had a bad coil and a vacuum leak was causing the engine knock retard. Check your ignition system.

unioncarpenter84

iTrader: (22)

whats the disadvantages with tht fuel??

unioncarpenter84

iTrader: (22)

will the knock doing anything besides rob ur hp

OnyxY2KSS

Knock=detonation=possibility for catastrophic engine failure. If it is true knock then you need to see about finding the source.

unioncarpenter84

iTrader: (22)

ya have no clue on cool nights at wot theres none at all then on some hot days there three to four

OnyxY2KSS

Hot air is less dense and requires less timing. I assume that that LT1s have intake air temperature sensors and should pull timing as intake air temperature rises.

joelster

What if it is picking up some other noises and thinking that is knock? The higher octane fuel may do nothing in that case.

unioncarpenter84

iTrader: (22)

ya thts what im thinking it may be false knock unsure

fex77k

iTrader: (2)

My scanmaster would pull around 4 (I'm not sure if that actual knock or a rattle causing it) on a hot day if it was cool out I wouldn't see any, when running 104 I knew that I had a larger safety margin.
No disadvantage on running higher octane, well cost is about it. You will have to experiment to find what your car needs.

Atomic

iTrader: (37)

Thats actually backwards; less dense requires more timing. Which is why the low load/vacuum portion of a spark map has such high timing and why boosted engines dont need as much. The air temp sensors pull timing because hot air is far more likely to detonate than cool air.

unioncarpenter84

iTrader: (22)

so ur still running it like tht?? is it holding together

fex77k

iTrader: (2)

It's in the 68 in my sig now, the compression is very good, and it ran a 9.6 on a cam only slightly larger than yours. It was a combination of a vacuum leak and a me destroying my MSD opti and coil. I think what you are trying to do is put a band-aid on the underlying problem.
This is the thread.

bufmatmuslepants

iTrader: (3)

You have GOT to quit trying to hide this problem and solve it. There is no reason that your 11:1 compression engine should be having a knock unless there is a legitimate problem. You keep hiding it, you could destroy your engine.

gregrob

iTrader: (8)

Get a real tune

unioncarpenter84

iTrader: (22)

i called my pcmforless he said its right on soooo......................

there is no exhaust hitting off floor or anything..
no check engine lights so i have no idea

LilJayV10

iTrader: (39)

I agree.

Either the OP has more compression than he thinks or there is something else going on.

LilJayV10

iTrader: (39)

Acutally I don't see where he lists his compression ratio, head gasket thickness, quench...

bufmatmuslepants

iTrader: (3)

He did in another thread that it was around 11:1, he also bought the car already built, from a guy who built the car to run a big hit of nitrous, and supposodly never ran nitrous through it.

You need to see if you can find someone who knows LT1s in your Pittsburg/Morgantown area and have them take a look, or your going to have to suck it up and take it to a mechanic. I would also take it to another tuner and have them take a look at what its doing, and see if they can fix it on the dyno. There is something seriously wrong if your car, which sounds like it should be making around 370-390 to the tires, cant trap more than a bolton only LT1.

Like was said in a few other threads you have started, PUT THE THING ON THE DYNO, at a shop that knows how to tune LT1s.

ZFreie

Even a dyno run with a wide band might give some more insight as to whats going on.

Also, have you run any higher octane through it to see if its false knock?