Cheuk in Seoul

I am running a RE Wing large street port with low compression rotors. APEXi RX6A (US kit), midpipe, cat back, underdrive pulleys, 1200 secondaries, E6K.. yes tuned by Matt aka "HITman", CWC intercooler. Those are the engine mods.

Yes, that was on 89 octane fuel (Korean premium... why I run low compression rotors) at 15 psi. My corrected number was 417 RWHP.

Eric Michel

QUOTE]How about I just add a section to the photo gallery for dyno sheets? You can upload the images and all the details of the run there. Same result, but no clutter that we get from all the stickies up top.[/QUOTE]

That would work, thankyou


I appreciate your honesty but have seen a few Dyno charts posted in other threads that did not get put on this one. I also know there are several individuals on this forum from my area alone that could post Dyno charts if they wanted too. Having all of these in one location will provide an excellent reference resource, and isn't that what this forum is all about?

carcrazy

Here is my dyno:

RX-7 Dyno

403 rwhp 329 torque at 14 psi and 91 pump...



Rick
1993 RX-7

2DoritosOnAStick

Nice numbers. Beautiful car!

Eric Michel

I agree thanks for sharing Rick. I am curious about that second dyno chart, different turbo/boost control?

carcrazy

The first dyno was when the motor had a little more 850 miles on it. The tuning was quite conservative with about 14 psi peak and normally running about 12 psi. We were intending this to be a "rough-tune" to better break-in the motor. The last tune was the final tune. No components were changed. The system was pressure checked and ran at 14 psi. The timing is still quite conservative. We were going to run a 9,000 rpm redline and 16 psi, however, we achieved the power levels we wanted at only running a 8100 rpm limit and 14 psi.

What a difference a little tuning will do. Take a look at the torque curve - amazing numbers with the radical porting we have and rather small T04E. We were making 12 psi at 3,000 rpm...

The car will be shown down in El Cajon at a large car show this Saturday.

Thank you guys for all the nice comments. This car was a result of the hard work of X S Engineering, Dynamic Motorsports, Redline Engineering and most important - feedback from this forum.

Rick Boyd
1993 RX-7 (wife's sports car)
2001 911 Turbo (my sports car)
2000 Acura TL (my daily driver)
2001 Lexus LX-470 (wife's daily driver)

AJC13B

Nice numbers car crazy.

You will find that most non BP or PP ported turbo engines will make peak power around the 7000-8000rpm range, no matter what boost is run

carcrazy

You have an impressive setup! Very cool web site.

Currently, my turbo is a little small for the porting of the motor. It is funny... I see the boost and hear the boost, it just does not seem to lite. At around 4,000 rpm is when the motor seems to breath and ... "we are off to the races!" From around 3,000 to 4,000 rpm, it does have enough power to be aware of.

Mine is making peak hp around 6200-6300 rpms, a little shy of the 7k-8k range.

We are happy!

Rick

AJC13B

Peak power is made at 6300rpm and boost kicks in at 4000rpm? You sure everything is working right??

With a .96 rear, even on an unopened motor, I would say boost would cut in a little earlier!

My turbo had a massive front and an even larger rear (73mm blade and 1.22 housing) and boost cut in at 5000rpm. Now I have a smaller housing and blade (68mm blade and 1.05 housing) the boost cuts in 500rpm earlier.

It just sounds strange that peak power is developed so low...2 friends have 3rd gen engines in their drag cars, one made 720fwhp and the other 526fwkw and both were made in the low 7000rpm range. The one with 720 has run a best of 8.881 @ 152 and the other 9.3 @ 144. Both have much larger turbos than even me....strange indeed

Oh, sweet car and love those brakes

Eric Michel

All of the turbos I have seen that spool fairly quick 3-4K seem to become restrictive around 6500 RPM on the higher boost levels. Did you data log your boost when making these runs?
I have a SMIC that runs very hot on a chassis dyno, the runs I posted were with no cool down, maybe 5 min between runs. The first run on a cold car always shows 15-25 more HP, just for fun I might try spraying some ice water on the IC/intake.
Rick, I would love to see a dyno chart on that Porsche

What happened to the Dyno sheet Photo gallery section?

Wargasm

You can see my car's latest numbers (ran out of fuel to try for 400+) here:

http://www.zeroglabs.com/rx7/dynoresults.htm

Keep in mind that I stopped my test at 6500 and was running only 12 psi. Target is 15 or 16 psi and 400+ rwhp.

Brian

SPOautos

Hey Rick, I noticed something wierd about that dyno chart. The hp and tq are suppose to cross at about 5250 and yours crosses at around 6750.

Anyway, just thought I'd point that out. Looks good though

STEPHEN

cyanide

yeah that dyno chart is inaccurate i think. hp and tq are supposed to be equal at 5252 rpm. that is becuase the formula for hp is:

horsepower = (torque * rpm) / 5252

matty

forgive me here but i am having trouble understanding the purpose of going single. Given the fact that you could make 350-360 with the stock twins and that most of you are making 390 with a single setup which costs an incredible amount of money to do right, i do not see the cost/reward there. Is it that you stock twins were shot so you went with a single? Dont flame me..just looking at the reasoning.

13BAce

Some people do it because their turbos were no good. Others like the simplicity. The stock twins are great, but they can't do too much more than 360. Most big singles, while making about 400 at 15-16 PSI, can make considerably more at higher boost levels.

richjackson7

no rats nest is why we do it

Eric Michel

His HP and Torgue graphs are not aligned, that is why it appears that they are crossing at a higher RPM. If you line the graphs up they do cross right around 5200 RPM.

Wargasm, your numbers look good but it looks like your boost leveled off around 10PSI from a little over 3K to 5.5K and then rose up to 12PSI. If you compare your graph to my 10/12PSI graph I think you will see what I mean. You may just need to adjust your boost controller gain, I am trying to get mine so it doesn't start dropping off in the higher RPM.
I like to see nice flat torque curves, that is why I was curious with the old Graph from carcrazy. His newer graph was not as smooth, I was trying to understand why. Since he didn't change anything accept for tunning I think it is just a matter of getting the boost control set properly. If you can get the boost/torque to hang in there through the higher RPM's thats worth some power. What do you guys think?

carcrazy

Good catch. In order for me to gain some more midrange punch for the wife, we increased the boost a little for just the midrange - this gives the slightly elevated torque readings starting at around 5000 to 6500 rpm (around there). Otherwise, the torque readings would read about the same as before.

regards

Rick

BOOSTD 7

Here is the URL for the Dyno Sheet gallery.

https://www.rx7club.com/photo/index.php?cat=549&thumb=1

As it says, make sure and enter all the info about the car when you post pics.

SPOautos

I dont think i follow what you guys are saying about Carcarzy's graph not being aligned? If you line them up to where the hp and tq crosses at 5252 then they show completely different numbers then what its currently showing.

Maybe I'm not following you guys.

STEPHEN

Eric Michel

The scale on the left is for HP, the one on the right is for torque. If the scales are aligned the 300HP scale position would be in the same vertical position as the 300 ft-lbs mark. On his graph 300 ft-lbs is at the same vertical position as 450 HP. If you re-scaled the torque graph so that 300 ft-lbs lined up with 300 HP the torque curve plot would move down and you would see the torque and HP cross at 5200.
If you look at the graphs I posted, some are aligned and some are not. You can select to align the graphs on the dyno computer if you remember. You need to be very conscious of the scales when reading dyno charts. You may have noticed that some charts look very different but most of the differences are due to different scales being used.

Eric Michel

Carcrazy, how did you adjust boost at different RPM? I think the AVRC has this feature? I know that adjusting the gain on my Profec-B will cause the boost to fluctuate at different RPM's but....

carcrazy

This was adjusted with the AVCR. I guess I need to request another dyno graph with the scales aligned - this would be interesting to note if they do cross at 5250 rpm.

regards

Rick

Eric Michel

No need if you look closely you can see that it does, at 5250 RPM you are seeing aprox. 300 HP, at that same RPM you have around 300 ft-lbs. The older graph shows the same cross over RPM only the HP/Torque are at 280.

Regards,

Eric

Wade

iTrader: (1)

School them Eric...

Wade