He's going the distance, he's going for SPEED

[WeathermanShawn]

Yea, I have it in one of my previous attachments (from a prior thread) I will find it and reload the dyno sheets shortly.

..WeathermanShawn..

[kwhiteside]

I'd rather have a strong running car making ~98% of it's power potential that I can drive aggressively and not have to worry about engine failure VS a car that pushes the ~102% threshold at the cost of longevity.

I'm with you there. I would be very happy with 98%. I doubt I'm close. I really wont know until I figure out where too far is. I'm pretty sure the dyno guys push to that point and then back off a bit. That is where my mind is.

Guess this thread wasn't a good idea.

[WeathermanShawn]

That was the thread I posted my dyno sheet. I also added an Excel printout. I had one of the dyno's that computed HP vs engine speed, instead of RPM. So I converted it and took their STD numbers 'down' to SAE.

In any case, the combo of a 110+2 cam and the smaller intake runners of those 'Terminator' Heads (200cc) gave a healthy low-upper middle Rpms TQ curve. Remember I lose some of that HP at this altitude, so this was my recipe to combat that loss of throttle response that occurs up here in the thin air.

[GMPX]

And now I have that song by Cake stuck in my head thanks to your thread title!

[SSpdDmon]

SSDmon, I am kinda embarrassed by my ineptness in downloading attachments.

I got through all the tuning myself, but always had the wife help with some of the technical skills with the computer (hey I just being honest).

That was the thread I posted my dyno sheet. I also added an Excel printout. I had one of the dyno's that computed HP vs engine speed, instead of RPM. So I converted it and took their STD numbers 'down' to SAE.

If you know how to re-attach them, please do. And don't laugh to hard..I have not conquered the 'attachment' skills yet...


http://forum.efilive.com/showthread....7294#post97294

In any case, the combo of a 110+2 cam and the smaller intake runners of those 'Terminator' Heads (200cc) gave a healthy low-upper middle Rpms TQ curve. Remember I lose some of that HP at this altitude, so this was my recipe to combat that loss of throttle response that occurs up here in the thin air.

Let me know if there is a problem in viewing those attachments via the thread link.

Click on the picture in the attachment. This will darken the screen and give a preview. Click on the preview picture. This will take you to a new window. Right click and save picture as to your hard drive (desktop is easiest). Then, you can attach the saved file (.jpg) in a new thread.

I love that combo you have....and it looks like you're still on stock 28# injectors. It must be a blast to drive.

And now I have that song by Cake stuck in my head thanks to your thread title!

Bwahahahahaha....

[WeathermanShawn]

Thanks for the compliment. It took about a year before deciding on that combo. It took some work adjusting the spark..with that setup it does not take long to build up some cylinder pressure. I have a pretty steep 'ramp down' in spark past .32 g/cy..ending up at ~22 at WOT.

Yea, it is a blast on the street. As far as the injectors, yes still stock. I am only saved by the altitude. I hit about 80-85% 'capacity' at 5400'. If I go down to 3000' I need more injector.

Thanks for the quick tutorial on attachments. I have used a lot of your idle tutorial and built my spark curve(s) on some of your tunes. I ended up playing with a little more advance in the air cylinder airflow values.

I also ended up doing the MAF calibration tuning (closed-loop hybrid MAF/VE tune). But, overall the +12% I ended up adding to the MAF, could have been easily handled by the IFR adjustments you recommended. I just had to remember to lower the VE Table by the same amount to keep consistent airflow values. It actually did work..I just ended up back to this tune. But I do not think anybody has proven you 'wrong' on the concept.

To the original OP..don't be sorry you posted. We are probably just more conservative than you. If you are looking for the maximum..try 12.9-13.1 AFR at WOT, and slowly bump your timing up to 25-28 degrees past .60 g/cy.

Maybe your car will respond accordingly. The shop might be also leaning conservative.

[SSpdDmon]

Thanks for the compliment. It took about a year before deciding on that combo. It took some work adjusting the spark..with that setup it does not take long to build up some cylinder pressure. I have a pretty steep 'ramp down' in spark past .32 g/cy..ending up at ~22 at WOT.

Yea, it is a blast on the street. As far as the injectors, yes still stock. I am only saved by the altitude. I hit about 80-85% 'capacity' at 5400'. If I go down to 3000' I need more injector.

Thanks for the quick tutorial on attachments. I have used a lot of your idle tutorial and built my spark curve(s) on some of your tunes. I ended up playing with a little more advance in the air cylinder airflow values.

I also ended up doing the MAF calibration tuning (closed-loop hybrid MAF/VE tune). But, overall the +12% I ended up adding to the MAF, could have been easily handled by the IFR adjustments you recommended. I just had to remember to lower the VE Table by the same amount to keep consistent airflow values. It actually did work..I just ended up back to this tune. But I do not think anybody has proven you 'wrong' on the concept.

So thanks.

To the original OP..don't be sorry you posted. We are probably just more conservative than you. If you are looking for the maximum..try 12.9-13.1 AFR at WOT, and slowly bump your timing up to 25-28 degrees past .60 g/cy.

Maybe your car will respond accordingly. The shop might be also leaning conservative. Good luck.

..WeathermanShawn..

Nice work. I take it that was the tune in it while on the dyno? Does it knock any if you flat-lined WOT @ 24* or 25* advance? I just ask because that's probably what I would have set it up for as a baseline (with a 12.5:1 AFR target in the mid range) . It might also get rid of that slight dip in torque/power at 4K RPM.

[kwhiteside]

I also run 'only' 22 degrees of timing at WOT. I put it up on the dyno and we saw no gain taking it up to 25-28 degrees. All it did was knock.

You got me thinking when you said that. I know my tune and there was absolutely no way I had 22 degrees at full throttle. If I did, I can see why you would think I was getting very greedy and wreckless. (BTW, I noticed in the hijacked thread part that you guys are doing 24-25 degrees) Notice this new pick backed up just a little. This is full throttle @ 19 degrees, very conservative guys. The first pic showing 22 degrees was going down a hill with me letting off the throttle. Yes I picked up speed even letting off throttle. I'm not the maniac you think I am, it gets real scary heading into a 90degree turn at 135mph.

So please reconsider your comments based on the reality here. I'm only getting 19 degrees at full throttle and I want to know the process of getting more. Nothing maniac like 24 or 25 degrees, but as much as I can get to the point just before it starts knocking. That is SAFE to me.

[SSpdDmon]

You got me thinking when you said that. I know my tune and there was absolutely no way I had 22 degrees at full throttle. If I did, I can see why you would think I was getting very greedy and wreckless. (BTW, I noticed in the hijacked thread part that you guys are doing 24-25 degrees) Notice this new pick backed up just a little. This is full throttle @ 19 degrees, very conservative guys. The first pic showing 22 degrees was going down a hill with me letting off the throttle. Yes I picked up speed even letting off throttle. I'm not the maniac you think I am, it gets real scary heading into a 90degree turn at 135mph.

So please reconsider your comments based on the reality here. I'm only getting 19 degrees at full throttle and I want to know the process of getting more. Nothing maniac like 24 or 25 degrees, but as much as I can get to the point just before it starts knocking. That is SAFE to me.

Aftermarket cams and the stock LS6 cam perform a little different. For example, my stock '02 Camaro only liked about 19* of timing at 4500rpm before it would knock. However, throw a 232/236 cam in there and I could flat-line WOT timing at 27* from 3Krpm on up. If you're still running stock timing, I'd suggest bumping it up 2 degrees from about 3500rpm on up. Keep an eye out for KR. If you don't get any, then you could try another 2*. But once again, you need to do this on a dyno to make sure the extra timing is making a difference. Once you find the sweet spot, start leaning it out some (again watching for KR). Since you race on a road course, I wouldn't suggest going much leaner than 12.7:1 or 12.8:1.

[WeathermanShawn]

Kwhiteside:

Sorry for the HJ. Sometimes just the nature of a thread. A lot of people stay on the sidelines just reading the threads, and sometimes they can learn even more when the topic expands.

Specifically on your situation. Whether spark or fueling it is always hard to know whether to follow an arbitrary number or as Jeff stated find your 'sweet spot'. Granted 19 degrees of timing sounds low. Also from your log, your ECT and IAT were pretty hot. I do not know how you have those spark tables setup, but it is getting close to spark retard anyway.

On the broader topic, Jeff hope this will answer your question. That dyno run was done on 28 degrees of timing on 93 Octane gas in Lubbock TX. I would pick up knock once it got warm. I repeated a dyno session out here in Denver. It could sometimes take 24-25 degrees, but I actually picked up an additional 7-8Hp by going down to 22 degrees. On the street it would 'ping' at 25 degrees. At 22 degrees it performs flawlessly. I have since gotten rid of that 'spark hump'.

So, Whiteside..by all means try to find that sweet spot. As Jeff will tell you, even after leaving a dyno, sometimes you find yourself readjusting the AFR and spark on the street. For me, that meant more fuel and less spark.