SStrokerAce

BIG SHAFE....

I'm sorry man but Denny is dead on, you give the motor what it wants not what you think it wants. The A/F ratio that makes the most peak TQ or peak HP can be all over the place. It's generally in a range but it can be much leaner than 12.7:1.

Why? Well there is a number of reasons, could be the injector timing, not how long it's open but when it's opened in the iduction cycle. Wet Flow, the intake/head can easily be dropping the fuel out of suspension. That will leave you with a larger amount of unburned fuel in the cylinder and showing a richer A/F ratio than what is actually being burned. Remember A/F ratio monitors are the tail wagging the dog, and a monitor to tell you that you are close. Nothing is dead on unless the dyno says so, and even then the acceleration rates of the dyno and the motor going down the track are usually drastically different.

Bret

Denny McLain

That's why I backed away from this thread a little irritated as frankly I could car less what the ratio comes out. Whatever the car wants.....is what the car wants and some like it a little leaner and some a little richer! In the tuning process you get the car to a certain point of confidence in timing and air/fuel and then play with it some more to see what works best.

I read things too like Dittwhiller (sp?whatever) paper presented to the SAE on fuel/air ratio but it's not been my real world experience that LTx cars making max power fall into an exact ratio. What could or can I say except what I've seen??

Tuff to deal with someone hasn't done it, but knows it all. Not into the mean spirited stuff, but damn.....give me a break.

lt1chevelle

i think he said 47lb injectors. isent that kinda over kill i have le2 heads and a gm847 cam with 1.6 rr and all supporting mods and LE said to run 37lbs.

BIG SHAFE

See something like this makes more sense to me. Not you (Danny) saying "dumb kid", "you only know books", "medical field experience", "my friend Bob Norwood", etc. All you did was skirt around the topic and basically try to belittle me. No examples, no explanations, just B.S.

Thanks Brett for the informative reply, I never thought about those things and it makes sense to me. Hopefully next year I will be doing some in car tuning and let you guys know what it likes.

mdacton

Denny McLain

Sometimes you get what you pay for.

You were more interesting in trying to be cute and difficult challenging my tuning skills and experience than learning anything. You knew it all. I called BS on your experience to make such a challenge as clearly you were quoting someone else’s work with none of your own and you were out of line with your approach.

The people I associate with have asked me point blank to not give out exact tuning methods or exact fuel/air just like I don't give out Bret's cam specs. Professional respect and courtesy. Like how much "free" do you expect to do when you start doing this for a living??

In the case of tuning there really isn't a set figure that I could give you anyway, but a normal divergence leaner than you were talking about and that the gods truth as I know it. There was nothing to, or I could debate. You were getting bad information in the regard to LTx cars. Know exactly how to tune one of these cars to max power but every now and then something surprises me. If you don’t grow as an individual, you go and I always keep a very open mind. You were not.

Worked on cars with Bob Norwood and in the past has let me drive his personal Ferrari and I value that experience. Bob is an absolute hoot, incredibly gifted and some of the stuff he comes up with blows me away. Always been a standup individual at everything and if I can help someone in any way. I do. Sometimes good things do come back.

BIG SHAFE

Not once did you say you did tuning, that was the first thing I was trying to find out. All I got out of you was that you've seen lots of pulls and you've worked with people. If you would have said point blank you tune these cars, know how to tune I would have said "ok, you know what you are talking about and I'm wrong".

The first impression I got from you is you've been around dyno's, don't tune, and that I'm wrong.

I understand professional courtesy, no problem there.

Tell me how I should have approached it? You say nothing in the beginning about you, yourself tuning cars. Tell me where to go next.

How am I supposed to learn or accept what you say when you call it a wifes tale and basically say books mean little compared to experience? Is that really a counter arguement?

I'm not being sarcastic here, I want to know how to argue/comment better so this doesn't happen. Back to the drawing board I guess since my logic doesn't seem to work.

stereomandan

Back on topic, the dyno numbers look fine to me especialy with 1.52 rockers. I would guess that you are giving up about 15 rwhp right there. Don't see any break-up up top and the curve is nice and smooth.

Dan

STAYBG87Z

dont put the th400 in unless your running a bigger c.i. motor,it will just hurt your performance,if your gonna go that route you should get a th350,it takes less power to turn!i would opt for the 4l60e but beef it up and youll be fine.