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-   -   how much power from stock internals (https://www.rx7club.com/1st-generation-specific-1979-1985-18/how-much-power-stock-internals-94829/)

moremazda 07-10-02 05:42 PM


Originally posted by REVHED
Now for a little rant. :) When are you guys going to realise that dyno numbers are not the be it and end all?

So are you saing that you believe him, when he says someone pulled 170hp out of a stock port 12a? Mabey if he were in Antarctica, in the winter!!!!

I will agree with you on the point that dyno numbers are not the end all say all for performance modifications. However, real numbers, especially a before and after comparison, will do justice to the fact that a part either helps or does not.

To support Revhed's position, Rotorhead reports that he hit 117hp with a DHLA, I hit 112hp with a stock Nikki. Now we all know that a side draft is usually worth more than 5hp over the stocker. Different altitude, ambient temp, yadda yadda.

But when person "A" out of the blue says that they are seeing 20 hp more than person "B" with the same setup, "PUT-UP or SHUT-UP"

The Dyno is the "put up" of the "put up or shut up" phrase. Most of us not being able to compare side by side on the back roads can use these numbers generated by others to determine which mods are right for our individual needs. I will stop believing in dyno numbers when I see that different people in different areas are no longer getting similar results from similar mods!

170 hp, sorry I must do I again:D
:bsflag:

Directfreak 07-10-02 05:48 PM


Originally posted by moremazda
170 hp, sorry I must do I again:D

Hold up...

Let me get it on the Dyno, and let you know guys know
for sure..

No fucking around - the real deal,


































The Bullshit Dyno
http://thelittlebaby.dhs.org/kenny/sweet/bsmeter.gif

Yep. It's 170HP worth of Bullshit allright..

rotorhead 07-10-02 06:26 PM

no peejay, but i wish i had.... i think that damn thing is holding back at least a couple more hp! not a prob though, welding together a RB header for it later this summer, with a rb presilencer, not sure on the muff yet.... maybe dynomax. whatever makes my wallet scream less

REVHED 07-10-02 08:45 PM


Originally posted by mar3
load cell type dyno = chassis dyno ???
Yeah, the chassis dyno's we use over here are of the load cell type.

Load cell dyno's allow you to adjust the load and speed of the dyno which is very benificial. On a turbocharged car for example you can hold the engine at a fixed rpm and gradually increase the load on the dyno which allows you to tune at different boost pressures. You can also hold the engine at a certain rpm and boost, adjust the ignition timing and see the immediate effects on power and torque.

Dynojet dyno's on the other hand simply calculate power by measuring the effort it takes to accelerate the rollers during a run. You don't get any of the benifits of being able to perform steady state tuning like with the load cell dyno's.

Barwick 07-10-02 10:41 PM


Originally posted by moremazda


Leason number one kids, how to say BULLSHIT, with the flag.

:bsflag:

I'm calling your bluff, bust out with dyno sheet!!

Do you want me to have him scan the dyno charts for me and upload them?

This dude doesn't screw around. It's a complete rebuild using all stock parts (race legal specs.. he might be able to use a different material for the seals, I'm not sure, I doubt it) and he tunes it to whatever he can do. His own custom exhaust, own (Heintz Bros) intake, rejetted carb (or holley, I don't know what one he uses), custom ignition, whatever pullies for the water pump to handle the RPM, the whole works. This setup as I understand it costs at least $3500 for the whole full rebuild, dyno time, labor, etc.

You don't understand.. if you shift the powerband up a few grand (these engines run up to 9 grand so I hear), and make the same torque that you did before at a lower RPM.. If you make 110 ft-lbs of torque at 5252 RPM, you get 110 hp. If you make 110 ft-lbs of torque at 8000 RPM (entirely possible if done correctly) then you make 167 hp. Or better yet, make 100 ft-lbs at 9000 RPM and make 171 hp.

Rotaries torque curve is like Kansas flat. Shifting it up can't be that hard if done properly.

Barwick 07-10-02 10:50 PM

By the way it's not a chassis dyno. It's flywheel horsepower. You're trying to tell me that people getting 150 at the flywheel can't squeeze another 20 out of the engine by enough screwing with the flows, timing, and whatever else?

Barwick 07-10-02 10:57 PM

ok I just sent an eMail to him and I'll call when they open up tomorrow.

Directfreak 07-10-02 10:57 PM


Originally posted by REVHED
Yeah, the chassis dyno's we use over here are of the load cell type.

Load cell dyno's allow you to adjust the load and speed of the dyno which is very benificial. On a turbocharged car for example you can hold the engine at a fixed rpm and gradually increase the load on the dyno which allows you to tune at different boost pressures. You can also hold the engine at a certain rpm and boost, adjust the ignition timing and see the immediate effects on power and torque.

Dynojet dyno's on the other hand simply calculate power by measuring the effort it takes to accelerate the rollers during a run. You don't get any of the benifits of being able to perform steady state tuning like with the load cell dyno's.

You are absolutely correct. however some dynojets (as an option) have air brakes which they can adjust via dial, therfore causing more resistance / load.

One of the local tuners here uses the load/brake for tuning his own personal race car, to do exactly that which you stated above. Most people in the states don't use it, because it would result in lower (percieved) horsepower. Over here it's a numbers game.:rolleyes:

RXcetera 07-10-02 11:06 PM


By the way it's not a chassis dyno. It's flywheel horsepower. You're trying to tell me that people getting 150 at the flywheel can't squeeze another 20 out of the engine by enough screwing with the flows, timing, and whatever else?
LOL! You make it sound so easy... Do you have any idea how much "squeezing" it takes to get to 150hp on a stock port 12A?? 150 is the limit... it's a figure that can be reached by optimizing EVERYTHING. Where do you plan on finding this extra 20hp?

Directfreak 07-10-02 11:14 PM


Originally posted by RXcetera


LOL! You make it sound so easy... Do you have any idea how much "squeezing" it takes to get to 150hp on a stock port 12A?? 150 is the limit... it's a figure that can be reached by optimizing EVERYTHING. Where do you plan on finding this extra 20hp?

I know how. The Baby Bottle.

He did it with NOS!
https://www.rx7club.com/forum/attach...&postid=832166
Oops.. sorry.. with a Nitrous Oxide System:wink:

Barwick 07-10-02 11:25 PM

Ok, you say whatever you want, I'll get the dyno from him and get his story straight tomorrow ok? I'm just going on what I heard, and all the racers swear by this guy.

Directfreak 07-10-02 11:31 PM


Originally posted by Barwick
Ok, you say whatever you want, I'll get the dyno from him and get his story straight tomorrow ok? I'm just going on what I heard, and all the racers swear by this guy.
I messin with ya man..:peace:

Rotor13B 07-10-02 11:41 PM

speaking of Ari Yallon, i spoke with him and Steve Kan on and off for a few hours last Sunday at the import drags. I even got a few tips and will let you know how they work out. :)

Barwick 07-11-02 11:33 AM

I just got off the phone with him, I was mistaken, they just got ITA legal 12A's running around 163 hp.

Now, their E-production 12A cars (you can street port 'em) are running around 230 something, fastest in the country.

moremazda 07-11-02 04:23 PM


Originally posted by Barwick
I just got off the phone with him, I was mistaken, they just got ITA legal 12A's running around 163 hp.

Dyno sheets any one?:D

How are they making this number I really want to know!!

nimrodTT 07-11-02 04:33 PM


Originally posted by moremazda
How are they making this number I really want to know!!
Do you expect them to release all their trade secrets to the public?

moremazda 07-11-02 05:02 PM

It's spec racing! Either they are cheating or they have figured out a way to break the laws of physics. They claim to be producing more HP than anyone ever has in the last thirty years. Thirty years of countless R&D projects, thirty years of tunning race cars. Granted this might be a mile stone, but ONE claim with no proof, and no explanation. Come on.

I'm not going to believe this untill I see the tear down!!

Ryan

Barwick 07-11-02 05:41 PM

If you've got the money to buy one, go to www.sdjmotorsports.com and call up, ask for Stan. Talk to him and have him rebuild your core into an ITA motor. Then go to his shop and watch as he runs your motor on the dyno.

Zulu 07-12-02 01:31 AM

K&N on CAI, Racing Beat Header & exhaust
Methinks a streetport (not confirmed)
on an '85 GSL-SE w/ working 5th and 6th ports :)

Can walk my buddies mkiii supra turbo w/ hks downpipe and 3" exhaust from a 3rd gear highway roll, steady pulling until we shut it down, and slaughter him from a dig. :)

RXcetera 07-12-02 10:41 AM

Those Mk3's are sllloooooowwww....

peejay 07-12-02 12:00 PM


Originally posted by REVHED
Yeah, the chassis dyno's we use over here are of the load cell type.

Load cell dyno's allow you to adjust the load and speed of the dyno which is very benificial. On a turbocharged car for example you can hold the engine at a fixed rpm and gradually increase the load on the dyno which allows you to tune at different boost pressures. You can also hold the engine at a certain rpm and boost, adjust the ignition timing and see the immediate effects on power and torque.

Dynojet dyno's on the other hand simply calculate power by measuring the effort it takes to accelerate the rollers during a run. You don't get any of the benifits of being able to perform steady state tuning like with the load cell dyno's.

I'mn trusting the numbers on Yaw's site mainly because there was no chassis dyno bullshit... the engines were dynoed on a proper ENGINE dyno. The way it should be.

peejay 07-12-02 12:02 PM


Originally posted by RXcetera


LOL! You make it sound so easy... Do you have any idea how much "squeezing" it takes to get to 150hp on a stock port 12A?? 150 is the limit... it's a figure that can be reached by optimizing EVERYTHING. Where do you plan on finding this extra 20hp?


And after you get 170hp you just adjust timing and the fuel mixtures some more and then get 190hp. And then do it again, etc. Pretty soon you have a 430hp stock port stock carb engine :)

mar3 07-12-02 12:15 PM

And then you add a non-intercooled Super Charger to hit the 780 HP mark just like the twin turbo F&F Supra's...;)

RXcetera 07-12-02 12:21 PM

Dude, you forgot the Nawsss :(.

David88vert 07-12-02 01:29 PM

I will say this. I have not dynoed my cousin's 85 GSL yet. Might never do it. But he has only made 2 modifications to his 180K mile 12a motor. One is a custom exhaust just like mine. The other is he put on the dual Rotary Performance intake with the Dual Weber 36's. That's it. Everything else is stock.
I put down 156.3rwhp/127.1rwtq on my 85 GSL-SE. He is pretty close to me. Definately safe to say that he has about 150 or more bhp.

If you want to call BS on me - race me first. :-)


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