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-   -   s4 213,000 miles dyno (https://www.rx7club.com/naturally-aspirated-performance-forum-220/s4-213-000-miles-dyno-986666/)

mario1386 02-06-12 08:11 PM

s4 213,000 miles dyno
 
1 Attachment(s)
ok my car has 213,xxx miles on the motor and chassis. I went to dyno meet on saturday and I decided to put the car on the dyno.

mods;
pacesetter header
obx-r 3in exhaust
emission removed
efans
11.7lb flywheel
exedy clutch
t2 drivetrain (tranny & diff)
k&n drop in filter

lastphaseofthis 02-06-12 09:52 PM


Originally Posted by mario1386 (Post 10968839)
ok my car has 213,xxx miles on the motor and chassis. I went to dyno meet on saturday and I decided to put the car on the dyno.

mods;
pacesetter header
obx-r 3in exhaust
emission removed
efans
11.7lb flywheel
exedy clutch
t2 drivetrain (tranny & diff)
k&n drop in filter

seems kinda high if you ask me... i'd like to see compression numbers from an engine with that many miles on it..

rotormind 02-07-12 10:35 AM

R u sure thats the original motor?

fidelity101 02-07-12 12:20 PM

Dynojets always read high

grantm3 02-07-12 04:00 PM


Originally Posted by fidelity101 (Post 10969681)
Dynojets always read high

Mustang dynos always read high... lol

rxspeed7 02-07-12 04:14 PM

^ your theory is wrong. Mustang dynos always read lower. Trust me, use one almost everyday. Usually dynajets figures are very close to flywheel hp.

mario1386 02-07-12 07:49 PM

Compression is at 110 psi all sides , and yes it is the original motor; i am the second owner of the car

mario1386 02-07-12 07:58 PM

Dynojets are inertia based, the computer knows exactly to the ounce what the dyno drum weighs, ours is a shade under 3000 lbs. Than it knows drum rpm vs. time. And takes a tach signal from the motor and instantly calculates the gear ratio. Knowing exactly what rpm the motor is at, exactly what the rpm vs. time the drum is at, and how quickly it accelerated that fixed mass (drum) it calculates Horsepower and Torque. This is how all Dynojets work. Now in the shop I have a brake that attaches to the dyno that can load the drum even higher to hit different map regions while tuning.


Most mustang dynos and the like use smaller much lighter drums. Load MUST be applied to do any dyno test. You must enter wheel size, estimate the weight, and other variables and program the dyno accordingly so it can apply load. Thats why they suck for repeatability. People will argue but it's true. If you want to do comparisons, you have hope the operator programs it exactly how it was previously. Every shop that DOESNT have a dynojet has to sit there and rationalize and explain how and why their dyno is better. Most even have sections of their website devoted to it. In the end, it's ET and other things that tell the true story. Dyno's are nothing but a tool, it's a big expensive torque wrench.

mario1386 02-07-12 08:00 PM

Dynojets are known to read about about 15% higher than most L&S, Mustang, DD dynos. 15% is about what most people use as a rough drivetrain loss. So a good estimate is that Dynojet numbers= flywheel hp. It doesnt matter what the number is, as long as you can see the change.

that depends who setup the Mustang or DD dynos. They vary operator to operator. Day in and day out we dyno brand new 2011-2012 Mustang GT's, they advertise 412 at the flywheel, and they ALL make about 360 (wheel) bone stock. GT500's advertised 500hp, and make 440-450 (wheel) day in and day out here. We had a 370z that made exactly what it was supposed to down to the single hp. We had a Powerstroke diesel truck that made 605/1070 on another dyno and 602/1081 on ours yesterday. We had a turbo 350z that made 10 LESS hp on our Dynojet than the Mustang dyno it was tuned on 2 weeks before. Bring me this car a month from now it'll read exactly the same hp. Thats why it's the industry standard. It's repeatable and accurate.

mario1386 02-07-12 08:02 PM

this was arguement that i had in my facebook cause some honda idiot didnt believe a 200,xxx mile motor still have that kind of power

farberio 02-19-12 12:20 AM


Originally Posted by rxspeed7 (Post 10969962)
^ your theory is wrong. Mustang dynos always read lower. Trust me, use one almost everyday. Usually dynajets figures are very close to flywheel hp.

I am pretty sure its because the dynajet dyno tries to spit out the flywheel hp, I believe it has a correction factor in order to do that.

Starfox07 02-20-12 10:24 AM

The torque curve falls off pretty hard after 6,000rpm. Are your 6 ports functioning?

mario1386 06-09-12 05:49 PM

^ i have the aux wired open

jorx7 06-09-12 06:56 PM

that power seems right, good for a motor with that type of mialage. just get a racing beat header! and junk that pacesalsa crap!

rx7freak13v 06-10-12 09:46 AM

ive been running a pacesetter header for quite some time now. i love it. the bends are more relaxed than the rb one and it is already collected. so i don't have to buy the collector or have one custom made. it's a really long tube header that i have, longer than the rb ones that i've seen, unsure if rb sells one as long as the pacesetter one i have? anyhow, i got it in a deal and am very happy with it. there is a reason why these guys are still around. however, my new engine is going to need much much much longer primary runners ;) so i thought about a custom one copying the pacesetter but with larger diameter. anyhow, the point is, is that the pacesetter isn't bad. i would buy another one, in fact i did buy a second for my brothers fc and have a third one sitting at my house chilling out lol. they are easy to find in good shape and really cheap.


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