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-   -   Proof is in the Paper !! (https://www.rx7club.com/time-slips-dyno-121/proof-paper-373372/)

Wargasm 12-22-04 07:45 AM


Originally Posted by ronbros3
about the dyno sheet the cross over is 6250 rpm while most sheets use 5250 rpm as a std. math formula using torque and RPM to figure HP, explain please. RON in daytona

Torque and horsepower do cross at the right point, but the scales used are different, so they look like they don't.

See my explaination on a similar situation here:

https://www.rx7club.com/showpost.php...5&postcount=46

rob20rx7 12-22-04 08:51 AM

your right that is exactly true, and because diff dynos measure on diff scales they for some reason or another are not going to look all the same. The dyno where i specificaly dynoed my car is a dyno jet. and we have been told that the dyno jet doesnt even meassure TQ to convert to HP. It actually measures by Speed and the way you turn the drum. this is why there may be a diff between this reading and others.

BigAl... 12-22-04 10:11 AM

If you guys call DynoJet 702-399-1423 they will tell you that you can adjust the software to move the crossover point, but it absolutely does not change the hp or tq. Guys, I tuned the car, it is definetely on the conservative side we could easily run two or three more degs of timing and run it leaner and probably make another 20-25hp but we want it to stay together. This car is awsome to drive, with almost 400lbs of tq :bigeyes: it pegs the needle on the ass dyno.

For those of you that don't beleive the dyno sheet the phone number to the dynoshop is 305-769-0140 ask for Mark he drove the car on the dyno. If you still don't beleive then setup some dyno time and we'll show up with the car. This post is no BS, neither Robert nor I stand to gain anything! I beleive Robert's intentions with this post were to post his results and findings to try and help others. Thanks to those who appreciate the hard work and to the others :flipoff: enjoy your keyboard racing!

BigAl...

Fatman0203 12-23-04 10:35 AM

Hey Al hows the idle (does it surge or is it higher than usual) with the 850 primaries?

GoodfellaFD3S 12-23-04 12:53 PM


Originally Posted by Fatman0203
Hey Al hows the idle (does it surge or is it higher than usual) with the 850 primaries?

I have had 850cc primaries along with my power fc for like 3 years now. No idle problems whatsoever, never have had any.

speedx7 12-23-04 01:18 PM

those are some good numbers

rob20rx7 12-23-04 05:33 PM

idle is about 1150 and nice and even. if there is any way to host a video i have a small 20 second video that shows the idle and how it looks

GoodfellaFD3S 12-23-04 06:38 PM


Originally Posted by rob20rx7
idle is about 1150 and nice and even. if there is any way to host a video i have a small 20 second video that shows the idle and how it looks

why so high? Also, please hit the drag strip so that we can see what kind of trap speeds you are laying down :)

Fatman0203 12-24-04 06:24 PM

Rob if you decide to go to a test and tune night in Moroso let me know I can get a few 7s to head out and maybe some of my friends. You can woop us all up if it makes you feel better ;). BTW I think my dad bought the Tokiko shocks and RB Springs from you. So far so good btw.

rob20rx7 12-25-04 12:10 PM

sure man im down to hang out. just tell me when. or maybe we can set up to hang out at the tower shops this january. havent been out there with the car. would be nice to head up there with a bunch of other rx7s. and yeah i sold my shocks and springs to this guy that told me his son had a 7. real nice guy. never heard from him again though. hope all is well and merry Xmas to you and all your family and to all of you the Rotary Forums.!!!!

RICE RACING 12-26-04 06:24 PM

Nice numbers ;)

With 100% water injection (no Alcohol) you can run over 30+psi boost with low comp rotors & richer AFR than on that run, but you need CDI on leading plugs if you dont already have that ?

Imagine how many doubting replys you will get then LOL

Nice work :)

rob20rx7 12-26-04 08:11 PM

i do have an MSD on the leading and i will now be installing the HKS twin power pack. But i dont know about being able to go to 30lb just with water. Have you actually done this or is this hypothetical?

Please reply

Thanks!!

RICE RACING 12-27-04 05:00 PM

On low comp have run 23psi on pump fuel only.

With 10.5 to 10.2:1 AFR and WI ratio 20% to fuel you can run easily 30psi on pump fuel and not exceed auto ignition point of common gas. 8.5:1 rotors make a fair difference compared to 9.0:1 and higher as you know.

PM me for more specifics & examples. But for an idea have reliably run 26psi on high comp (9.0:1) with WI only and pump. Running water only makes a big difference compared to Alcohol mixtures which will not pull out as much heat in the small volumes relative to the base fuel. Alcohol as a stand alone fuel is great but you need lots of it (main supply) for it to work its magic.

GO pure water, you willl be amazed how far you can push it :)

GT1-20b 12-28-04 12:56 AM

Rob, & Al,
Fist, Happy Holydays.
Can't sleep tonight, so I desided to check out your thread.
Must say, I'm impressed by all the EXPERTS out there!!
I specially like your term " Keyboard Racing ", I think I'll use it some time.
Funny how no mater what one does, their's allways those who will knock it.
As for the " X over point " on You're dyno run, the " 5250 " is a (K) constant used to calculate power in a formula that goes something like this: Hp. = (T) tourque X RPM / (divided by) 5250.
Were by pluging in any 2 variables, & dividing or mult. by the (K), you can solve for the unknown.
Keep it up, Represent !

GT1-20b

ronbros3 01-02-05 05:17 PM

WOW (havent been on this thread) didnt mean to stir up a hornets nest here, but talked to 3 defferent dyno operators all said software calibration should be calibrated to the excepted norm 5250 but does not have to be, it could change readings , maybe as much as 15-20%, not sure nobodys tried the 6250 crossover. dynojet said they prefer the std. because it does not really measure torque but time to rpm, sofware figures it from there. anyway Rons RX-7 87TII 13B FD 3rd gen 9.0 rotors 2 mm atkins seals 2 pc. ,850 cc primaries, 1600 cc seconds.street port, extrude honed manis., HKS exhaust mani coated, TO4-S garrett 62-1 comp., 1.0 a/r turbine coated, P- wheel clipped and balanced, HKS w/g ported, MICROTECH LTX-8, techedge wideband AFR, 4 crane hi-output coils 2 crane DIS2 boxes, custom water to air I/C, 3.5 " exhaust turbo to end, nitto 555R, 2660 lbs. on calibrated scale no driver, 1/2 tank fuel. SMC alcohol injection 2 yrs. tuned by Rolo Lopez at CFT Orlando HEY we might meet at Orlando Dragway be a fun race! sorry aint got no A/C, but carry a bag of ice for intercooler. thanks your friend RON .

Fatman0203 01-05-05 01:46 PM


Originally Posted by rob20rx7
sure man im down to hang out. just tell me when. or maybe we can set up to hang out at the tower shops this january. havent been out there with the car. would be nice to head up there with a bunch of other rx7s. and yeah i sold my shocks and springs to this guy that told me his son had a 7. real nice guy. never heard from him again though. hope all is well and merry Xmas to you and all your family and to all of you the Rotary Forums.!!!!

That was us! lol small rotary world. Nah they worked great, we thought we had a problem with them but ended up being the weak stock sway bar mounts. So we had to replace them. PM me for my number we can chill at the races anytime you want Tuesdays and Thursday nights, usually always some nice cars to run. It'd be nice to see the Cobra's "try" to run you.
Merry Christmas to you too! and New Year. Keep up the good work with the car.

Snook 01-10-05 01:17 PM

wow great to know theres still some competition and something to aim for!
Nice work you are now my rx7club hero haha.

I also have injection and I use 50 distilled water and 50 denatured alc. What kind of pump lube do you use? I suppose that is a good idea never really thought of it, I thought water was a great lubricant. Also does yours come on progressivly or at a certain boost level with a pressure switch? You'de want it to come on full force right at max tq right? Does everyone else agree that just pure water is more benificial? I thought that water did the cooling and the alc was able to raise the octane.

Thanks
-Yanni

Jdot 01-10-05 03:39 PM

I think that your situation will determine what is more benificial. If it was my car I would try to use high octane in the tank https://www.rx7club.com/rotary-car-performance-77/what-kinda-octane-boost-do-u-use-toulene-xylene-etc-339648/ AND have water/alcohol injection. Its all good though Rob just showed us that we can use 100% alcohol injection as a seemingly reliable option, and options are a beautiful thing.


J


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