My buddies race in all the SCCA events at the Q, and the course didn't go over the drag strip, but they could have a new layout this year. racelegal.com is their website, and they should have all the dates. Warr, it's hard to explain the launch surface. The track is concrete i believe but they have pads of some type that you launch from, and i always thought it had something to do with the the portable tree setup.

 

Ok, so it's at least better than when we do ProSolo's and just have to launch off the regular surface. They do at least attempt to have a launch surface it seems, so that's cool. I was only cutting mid 1.7s on the concrete at the National ProSolo last year, which disappointed me, but it's a lot tougher to launch with -3.0 camber on concrete than regular camber on a drag surface. However, some guys still hit 1.6s in Subies, so it was still doable. I would expect to still get low 1.7s on this surface at the Q, but you never know until you do it.

Looking at the schedule, they are not open that weekend, and are open both weekends before and after. No dice.

 

Warr, Look in 1 of my previous posts for the barona website. It's possible they might be racing that weekend and it's roughly 25 minutes from the Q. Barona is blacktop, and they prep that track very well. I had a couple high 1.6's there versus 1.7's at qualcom.

 

I am getting a small amount of wheel spin off the line, but nothing too bad. The next event will be held on February 22nd. I plan on being there for that event, and will start the tire pressure at 28psi and work my way down. Yes, I need to work on my overall driving skills.

This event is held in the parking lot of Qualcomm Stadium. It is a concrete lot, and they do apply VHT to one side of the track. Unfortunately it is the side where they have only been letting people with slicks or DRs run on.

 

The rev limiter is currently set at 8200 RPMs, but I have been shifting around 8000 RPMs because the stock turbo is running out of steam and the horsepower is trailing off.

 

You should not be shifting anywhere near 8k rpm. You should shift NO LATER than 7k rpm. You said yourself that the turbo runs out of steam, which is correct, but it starts to die off BEFORE 7k rpm. 8k rpm shifts are absolutely ridiculous. That alone will help your times...

Milldog, that's still just crappy 1/8th-mile which really does nothing for me. I'll drive up to Fontana for the full 1/4 if I do anything at all. I was only considering the Q stuff, because I'll be right there on site anyway.

 

I agree with what Warr said^^. I was mislead when i bought my baby and always ran it to redline, but when i had it dynoed then i could really see the power curve and made the adjustments. I think my personal shift points are: 7200 1-2, and 7k 2-3, 3-4( for pump gas).
Warr, i Hate the 1/8 mile too, but it was close and still enjoyable, but i must say that everytime i went to fontana i would get 2 runs at best. DEPRESSING!!

 

I just had the car dyno'd this past Saturday and here is the dyno graph:



The guy operating the dyno wasn't familiar with the mods done, so he stopped at 7K like he did on most other Evos. I believe the power isn't falling off until 7500 or so. So long as the car isn't losing horsepower in the upper RPMs, I would think I'd want to shift at a higher RPM so that I will be at or close to full boost in the following gear. Also, if I shift at 7K I will end up hitting 4th before the end of the 1/8, and based on my experience thus far that last minute shift is costing me precious time.

 

Warr,

If you are going to be at the Q this Friday night I'd be happy to give you a chance to see what times you could get out of my wife's Evo.

Justin

 

You're a little confused here. You let off at 7k on the dyno, so you have no idea what power it makes at 8k. I am here to tell you that the stock turbo does NOT keep making power after 7k rpm. There is a steep dropoff after 7k. In your case, it's pretty flat from 6k-7k, which is good, but you should be right in that range in every gear (6k-7k) and should not be going over 7k except for maybe a few hundred rpm. All you have to do is look at dynographs of the thousands of other stock turbo'd Evos showing this same phenomenon. Plus, the part about being at full boost in every gear is WAYYYYYYYYY off. We hit full boost below 4000rpm, and then it tapers continually from there on. The higher you shift, the LESS boost you will see in every gear, because you're in RPMs that are out of the turbo's efficiency.

Just because you shift around 7k in other gears doesn't mean you have to shift to 4th. Again, this is just standard fare. In the 1/4, many people will shift at 7k on the 1-2/2-3/3-4 and then ride out 4th as far as they can. In your case, you could do the 1-2/2-3 at 7k and then ride out 3rd as far as you can. However, that's one of the problems with the 1/8th-mile. You WOULD shift to 4th before the 1/8th-mile on a 1/4-mile track, so trying to keep it in 3rd on the 1/8th just gives false readings. As one point of reference, on my 6spd, I would hit _5th_ before the 1000' mark, which is halfway between the 1/8th and 1/4.

I live in CO, so I will not be in San Diego until Mar 14-16 for the SCCA event and then in El Toro 2 weeks later for another SCCA event.

 

First off I appreciate you taking the time to share your experience and knowledge with me.

Yes, these three dyno pulls were cut-off at 7000 RPMs; however, when my friend is street tuning the car it is tuned to 8200 RPMs. I am looking at the DLL graph right now. Peak power was 374 @ 6188 and the power drops to 325 @8000. I do not have access to Photobucket here at work so I cannot post a link to this graph until later tonight. However, the part about the power dropping off after 7K is true. In fact, the power is actually dropping off after 6500. I believe the reason for this is based on the fact that the tune is on 91 octane, and you simply cannot put as much timing into it without the fear of knock and detonation. If I had it tuned on 93 octane I believe the power would hold a bit longer.

The next attempt in making more power will be exhaust cam gear tuning.

 

No, the reason is the turbo - it's the same for all stock turbo'd Evos. Actually, the 91 is keeping you from dropping off EARLIER, because you're not running much boost. This is evident when you look at how weak your torque and mid-range are. With 93 or higher, you'd be running higher boost, which would give a much higher torque peak, fatter mid-range, and then an earlier dropoff, because the turbo would hit its efficiency limit earlier.

 

I've commonly heard that it is timing that makes torque, and the more timing you can run in the upper powerband the longer you can sustain the torque. Boost alone isn't the driving factor behind what makes more power.

 

Timing assists in all manners of power delivery, but it's 100% sure that it's your boost level determining the relative torque peak. Just look at anyone running race gas or alky on the stock turbo. They get HUGE torque, because the turbo is efficient early in the rpm band at high boost, but it falls off drastically as RPMs increase. You've either been talking to the wrong people or not fully understanding what they're saying. For instance, you could run more timing with higher octane, but you could also run more boost. Both can attirbute to addition torque (and HP, of course), but boost is the primary factor, at least in terms of the stock turbo.

Yes, the more timing you run at higher rpms, the more power it will make, assuming there is no detonation, but that additional timing is to make UP for the loss of boost from the inefficiencies of the turbo.

Of course boost isn't the only driving factor. I was talking about peak torque. Here's my example:



The rpm readings were off on the 93oct runs, so I'm unable to show the torque readings, but you can imagine them based on the HP curve. Look at the 4 curves: 19psi (93oct), 24psi (93oct), 26psi (93+alky), 28psi (93+alky). Notice the diminishing marginal utility. As I increase the boost, I get a lot more peak torque and mid-range, but my top-end only increases marginally, and that margin diminishes as boost increases. In fact, my 28psi HP curve dipped below the 26psi curve at high rpm. The tunes were the same on the 19/24 and 26/28, but the fuel was different. You can easily see how much fatter the mid-range is thanks to all the extra boost. Also, the differences in peak torque were huge. Here are the numbers are I remember them (not exact):

19psi = 307whp/280wtq
24psi = 330whp/330wtq
26psi = 341whp/361wtq
28psi = 347whp/383wtq

Take those numbers and digest them, then go back and read my previous explanations. Next, take your power curve and compare it to my 4 curves. Which one does it most resemble? The 19psi one, right? A slow, linear increase, then a plateau that stays flat almost all the way to cutoff. That's due to running lower boost levels that don't reach efficiency limits until very high rpm. The more boost you run, the earlier you reach that limit. In my case, I was on the stock FMIC and stock IC piping, so my limits were reached very quickly at high boost. Your FMIC helps delay it, but the 91oct of course counteracts that.

Oh, and based off the detected inefficiency at 28psi, I elected to go with 26psi for 24/7 use. I didn't think it was worth the 6whp/20wtq to run the turbo ragged all the time. I have been running 26psi since that day over 2 years ago.

 

I understand and agree with all that you are stating. When we have been doing some road tuning, we have tried adding more timing up top but start getting a few knock counts. 93 or higher octane would have allowed for those minor timing increases. More torque was achieved with this increased timing, but I wasn't willing to risk a few knock counts which could possibly increase under different environments.