1990 #2180 Dyno pull

[ghlkal]

If these numbers are accurate, I'm a happy camper :-D

RWHP 337
"corrected for temp/humidity/pressure" = 353

RWTQ 320
"corrected" = 335

(both at a whopping 5500 RPM or so)

They had some issues loading it on the dyno and by the time they were ready, the car was already pretty hot. I tried to convince him that redline was a little higher too ...

There was only one useful pull, and here are the sheets

http://i517.photobucket.com/albums/u331/NaturalCowgirl/ZR-1/dyno1_zps0d504fa4.jpg


http://i517.photobucket.com/albums/u331/NaturalCowgirl/ZR-1/dyno2_zps19f93688.jpg

http://i517.photobucket.com/albums/u331/NaturalCowgirl/ZR-1/ZR-1Dyno4746_zpsdf4fc2ad.jpg

The techs hadn't seen an LT5 in person, although several knew about it.

The only "mods" I have are Corsa exhaust and SLP claw intake. The engine runs great after I replaced the fuel injectors.

OK, gurus ... let me know your thoughts. Is this thing really 400HP at the crank?

[LGAFF]

yep, corrected thats 400-410 crank

[PhillipsLT5]

HP was still climbing at 5653 RPM

[ZZZZZR1]

HP was still climbing at 5653 RPM

I agree.... He heard the LT-5 roar and got scared!

shame he didn't take it further.

David

[Karl]

That's the same type of dyno (at least the website on the printout) that I ran my '92 on. The operator took my LT5 to the same rpm before shutdown.

Good numbers. With headers and a chip I would guess you will hit 370whp no problem!

[LGAFF]

Time to get headers and a ported top end....

[ghlkal]

I agree.... He heard the LT-5 roar and got scared!


:thumbsup:

Yup ... it got a little loud in there

http://s517.photobucket.com/user/NaturalCowgirl/media/ZR-1/Dynopull4745_zps99caacb0.mp4.html

(I haven't hosted a video on photobucket before, so I'm not sure this will work)

[XfireZ51]

My thoughts exactly. Power peak is too low. The WCF means With Correction Factor, but which one? SAE, Standard?

[Paul Workman]

Strong numbers, to be sure.

Researching dyno calibration specs a bit, it appears (cutting to the chase) that a 4% variance exists between STD & SAE correction factors, stemming from the fact that SAE normalizes to 77ºF whereas STD normalizes to 60ºF

Also, the SAE 1349 spec requires correction for torque, relative to the mechanical efficiency (ME), or estimated at 85% at peak torque ONLY.

It is still a little vague (to me) how ME is affected when the engine is producing other than peak torque, but intuition tells me as counter rotational force (drive train inertia) diminishes, ME increases. The result would be a reduction in calculated hp at those non-peak torque regions of the rpm band.

In any case, the dyno operator was obviously conditioned to lift when his ear told him he'd reached the limit of conventional pushrod motors. The sound of the LT5 screaming past 5500 on its way to 7k+ scares the crap outta some operators, and the unaccustomed as well.

Well...Now that the hook is set, it is time for some FBI top end porting...and then...and then... Yeah, speed is addicting! ;)

P.

[LGAFF]

put it on the real world dyno(track) and see how she does....

[efnfast]

Damn, the girls (at Mercruiser) built you a strong one. I had to do headers, K&N, exhaust and a chip to get to 353 RWHP on my 90.

[ghlkal]

That's the same type of dyno (at least the website on the printout) that I ran my '92 on. The operator took my LT5 to the same rpm before shutdown.


Yup. When I saw your numbers pushrod, I thought "wow, those are good numbers coming from a (conservative) Mustang dyno"


HP was still climbing at 5653 RPM

I agree.... He heard the LT-5 roar and got scared!

shame he didn't take it further.


I told him to look at the tach and notice where the redline was ... but anyway.

I'm happy with the numbers and they might even be a little higher :dancing

[ghlkal]

Time to get headers and a ported top end....

That's the next step. My ultimate goal is to get 400rwhp. It looks like headers, porting the top end and good tune should get me there.


Strong numbers, to be sure.

Researching dyno calibration specs a bit, it appears (cutting to the chase) that a 4% variance exists between STD & SAE correction factors, stemming from the fact that SAE normalizes to 77ºF whereas STD normalizes to 60ºF

Also, the SAE 1349 spec requires correction for torque, relative to the mechanical efficiency (ME), or estimated at 85% at peak torque ONLY.

It is still a little vague (to me) how ME is affected when the engine is producing other than peak torque, but intuition tells me as counter rotational force (drive train inertia) diminishes, ME increases. The result would be a reduction in calculated hp at those non-peak torque regions of the rpm band.

In any case, the dyno operator was obviously conditioned to lift when his ear told him he'd reached the limit of conventional pushrod motors. The sound of the LT5 screaming past 5500 on its way to 7k+ scares the crap outta some operators, and the unaccustomed as well.

Well...Now that the hook is set, it is time for some FBI top end porting...and then...and then... Yeah, speed is addicting! ;)

P.

Good info Paul. I _think_ the Mustang dyno directly measures Torque and then "infers" HP from that.

I'm hoping Pete is still "for hire" when I want to get the porting done.

With 400 to the wheels, I think that puts the Z in line with the C7.


Damn, the girls (at Mercruiser) built you a strong one. I had to do headers, K&N, exhaust and a chip to get to 353 RWHP on my 90.

Yup, I wish I knew who to thank!

What we all wouldn't give to get our hands on the original runs for each of our engines!