Guess' ????
TECH Regular
Joined: Sep 2013
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Okay, I have read most of your recent posts so figure responding here will do.
You say that the thing is 'popping' which means a lean condition. I am going to give you some sound advice as I have a lot of experience running A/F meters in cars full time, including turbo cars that I used to tune with aftermarket EFI management.
You cannot read that at WOT on the street/track that high 12's is rich, in real-world driving conditions this is not rich. On a chassis dyno you might find the reading to be in the high 12's which may be optimum, the same tune up when you drive it off the rollers and down the street can easily then read in the low 12's which is fine as generally the engine is not loaded up like it is on the dyno.
You need to add some jetting, get the mixtures in the low 12's because not all cylinders are going to be running the same A/F ratio, some will be leaner than others. But right now, your engine is bordering on a lean condition, and all changing timing will do is confuse matters further.
Put the pipes back on, run timing at 32* max and work on jetting up the carb, and don't worry about cruise A/F ratio's either, rich or whatever at cruise doesn't matter at this stage for what you are trying to achieve.
You say that the thing is 'popping' which means a lean condition. I am going to give you some sound advice as I have a lot of experience running A/F meters in cars full time, including turbo cars that I used to tune with aftermarket EFI management.
You cannot read that at WOT on the street/track that high 12's is rich, in real-world driving conditions this is not rich. On a chassis dyno you might find the reading to be in the high 12's which may be optimum, the same tune up when you drive it off the rollers and down the street can easily then read in the low 12's which is fine as generally the engine is not loaded up like it is on the dyno.
You need to add some jetting, get the mixtures in the low 12's because not all cylinders are going to be running the same A/F ratio, some will be leaner than others. But right now, your engine is bordering on a lean condition, and all changing timing will do is confuse matters further.
Put the pipes back on, run timing at 32* max and work on jetting up the carb, and don't worry about cruise A/F ratio's either, rich or whatever at cruise doesn't matter at this stage for what you are trying to achieve.
Doug you need to start a dedicated Doug G LSX thread where we can all refer back to all your car's details. I know I want to help you as do many others, and none of us want you to give up.
I find that I forget some of your combo's details so it makes it harder to try understand the whole combo's dynamic and give good advice
Barrett
I find that I forget some of your combo's details so it makes it harder to try understand the whole combo's dynamic and give good advice
Barrett
Thread Starter
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Joined: Aug 2010
Posts: 4,467
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From: Harford Co. Maryland
32* IS what it was at and the popping I'm sure was due to the fuel level.
Was only stating what the AFR meter read.... not hung up on A number.
I was testing the "theory" of my 2.5" system and/or Flow Masters being a restriction. Seems they're not. (As I was told .1-.2 maybe)
Yes, the exhaust is going back on.....for now.
Sitting back, drinking a beer or 12 for now....need to make a plan on where to start that doesn't include taking out the rev limiter and seeing how high and for how long it would go
Was only stating what the AFR meter read.... not hung up on A number.
I was testing the "theory" of my 2.5" system and/or Flow Masters being a restriction. Seems they're not. (As I was told .1-.2 maybe)
Yes, the exhaust is going back on.....for now.
Sitting back, drinking a beer or 12 for now....need to make a plan on where to start that doesn't include taking out the rev limiter and seeing how high and for how long it would go
TECH Regular
Joined: Sep 2013
Posts: 410
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Don't worry about theories on things that are based for guys who are already running good times and are looking for an edge to bump off a tenth or two, you are not at that stage at the moment.
The thing is running lean, and your setup is down on power. You need to add fuel to pick up power, then fine tune from there.
The thing is running lean, and your setup is down on power. You need to add fuel to pick up power, then fine tune from there.
When I installed that cam in my car, I used a degree wheel and had to advance the cam 4 degrees to make the ICL numbers come in correct. So if you didn't degree the cam, it might be a good idea. Eric L
what is the combo? if it is a 6.0, your true dual 2.5 with flowmasters IS a restriction. 3" dual with some kind of straight through muffler IMO
what valve springs. my engine popped when i lost an exhaust valve spring. went from 7.32 @ 95 to 6.86 @ 101 with virtually no other changes other than new springs.
what valve springs. my engine popped when i lost an exhaust valve spring. went from 7.32 @ 95 to 6.86 @ 101 with virtually no other changes other than new springs.
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Verdad Gallardo Thread Starter
10 Second Club
Joined: Aug 2010
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From: Harford Co. Maryland
It may not be a bad idea to re-check. Since I'll have the valve covers off I'll check the springs.
I'm looking at 3Pedals build (23X/26X cam) and see how high spun it on the dyno....I'd like to try shift at a lower 6500rpm and "see" if that changes anything.
I did shift at a few different points back in October and don't have that info now
As for the springs...they're a .660 lift dual spring, I'd have to dig that info up.
Last edited by Doug G; Jun 27, 2014 at 10:25 AM.
1st pass 11.80 @ 113....wtf ???
add 2* timing across the board....36* from 1000-8000rpm flat lined....change shift point from 7000 to 6500.
1.555 60' 11.33 @ 117.71....now we're getting somewhere
Change shifts to 6800 and timing is now 38* flat lined....11.327 @ 116.79 with a best ever 1.546 60'
happier, but feels like it's nosing over at top end of shift rpms.
Changed to 6600 shift and at half track get hit by a wind gust...butt hole pucked and I got out of it
Ended my day, and went home. I think I'm going to drop the timing to 37* for next time out.
Feels good lifting the tires again
More work to do.
add 2* timing across the board....36* from 1000-8000rpm flat lined....change shift point from 7000 to 6500.
1.555 60' 11.33 @ 117.71....now we're getting somewhere
Change shifts to 6800 and timing is now 38* flat lined....11.327 @ 116.79 with a best ever 1.546 60'
happier, but feels like it's nosing over at top end of shift rpms.Changed to 6600 shift and at half track get hit by a wind gust...butt hole pucked and I got out of it
Ended my day, and went home. I think I'm going to drop the timing to 37* for next time out.
Feels good lifting the tires again
More work to do.
I keep a timeslip anthology on a spread sheet complete with notes on each change and weather condition. I refer back to it often. It may even make an interesting thread someday.
Thread Starter
10 Second Club
Joined: Aug 2010
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From: Harford Co. Maryland
Well, texting a racer buddy who's really into this stuff and he ran some numbers for me.
Looks like my converter slip is fairly high...17% ...Have to see who will freshen it up.
Quench could be a little tighter
Dial in the fuel a little better
This equals about maybe .5 better and then add some good air.....
She'll have to do for now.
Looks like my converter slip is fairly high...17% ...Have to see who will freshen it up.
Quench could be a little tighter
Dial in the fuel a little better
This equals about maybe .5 better and then add some good air.....
She'll have to do for now.
I cant wait to hear how the cam degree checks out.
if you've never had a cam degree issue, you dont realize how much a couple degrees can hurt you. - from zero to hero - ESPECIALLY WITH SQUAREPORT LS3 HEADS
if you've never had a cam degree issue, you dont realize how much a couple degrees can hurt you. - from zero to hero - ESPECIALLY WITH SQUAREPORT LS3 HEADS