Rear wheel HP estimate

[Nacho_ZR1]

Greetings from Moscow! Quick question - realistically how much rwhp can I expect with ported heads/IH and Pete's cams. Also, what trap speeds and mph are ya'll running in the 1/4? Once i get back from my biz trip, I'll be taking my car to Corey so he can work his magic!

[LGAFF]

420-440rwhp; traps at 120-125, depending on how good a driver you are and tires you use

[Hib Halverson]

The Automasters "Street Skinner" engine in my 95 made 413 SAE-corrected at the wheels on a DynoJet with stock manifolds and cats.

If you add headers and cams to a 350 with head/housings/plenum work and cams I'd hope for at least 430 at the wheels. Anything less and I'd want my money back.

I'd say your speed in the quarter will be 120-130. As for the e.t? That will depend on your driving talent, axle ratio, rear tires and your suspension set-up.

[Fully Vetted]

I've got right at 420 to the wheels without cams. Pete did the port work and the SW headers. Have not been to a track.

[Hib Halverson]

420 at the wheels..SAE-corrected or standard-corrected?

[Fully Vetted]

Good question. Corey did the pull last month. I'll be picking the car up here pretty quick. I'll ask.

[Pete]

:)When i dyno'd that Z it made 425 SAE Corrected

I heard Corey got 428 out of it.

I think 430+ should be possible from that Z but then again every Dyno is different 420-430 is withen tolerance
Some shops have unfriendly dyno #'s till you drop some cash then they get you some friendly dyno #'s. [-X

This is why i always dyno'd at two different Dyno's just to compare.
Look up Dynojet tricks how they can play with Dyno #'s

What i have discovered at my 600ft elavation track and my Z with stock front wheel/tires.
370-380rwhp 115-117 1/4 MPH
390-410rwhp 117-119 1/4 MPH
415-430rwhp 119-121 1/4 MPH
435-450rwhp 121-123 1/4 MPH
465-475rwhp 128-129 1/4 MPH aluminum pullies half weight over stock saves 2.5lbs,ATI balancer minus 2lbs,flywheel/clutch set up saved a bunch
(200lbs overall total) :)

Pete

[XfireZ51]

Pete,

You've got the last 25 rwhp making a 5+ MPH trap speed?

[Pete]

Pete,

You've got the last 25 rwhp making a 5+ MPH trap speed?

Since then i re-ported my plenum/IH's a bit bigger i also mention i reduced rotational weight between pullies,ATI balancer,clutch/flywheel i'd say 25lbs maybe more and about 200lbs dead weight.

Pete

[Nacho_ZR1]

Since then i re-ported my plenum/IH's a bit bigger i also mention i reduced rotational weight between pullies,ATI balancer,clutch/flywheel i'd say 25lbs maybe more and about 200lbs dead weight.

Pete

Wow how'd you reduce 200lbs? Inquiring minds wanna know :-D

[Paul Workman]

420 at the wheels..SAE-corrected or standard-corrected?

Wel now... that IS the question.

It seems SAE standards evolved over time, introducing the oppotunity for different results for the same run, depending on which "standard" was applied. Add to that some calibration issues, and operator's attention to detail.... Makes for ambigeous results at best.

P.

[Fully Vetted]

:)When i dyno'd that Z it made 425 SAE Corrected

I heard Corey got 428 out of it.

I think 430+ should be possible from that Z but then again every Dyno is different 420-430 is withen tolerance...

Yeah, you've talked to him since I have. I'll have to update my sig!:-D

I'm still chasing Paul for power on stock cams, though.



Since then i re-ported my plenum/IH's a bit bigger i also mention i reduced rotational weight between pullies,ATI balancer,clutch/flywheel i'd say 25lbs maybe more and about 200lbs dead weight.

Pete, did you do the lightweight pullies on my car or is that something Michael did after you worked on it? I'm trying to determine if your 425 number was done before or after those were installed.

Wow how'd you reduce 200lbs? Inquiring minds wanna know :-D

Going from a steel flywheel to an aluminum one is most of it.

[Fully Vetted]

Wel now... that IS the question.

It seems SAE standards evolved over time, introducing the oppotunity for different results for the same run, depending on which "standard" was applied. Add to that some calibration issues, and operator's attention to detail.... Makes for ambigeous results at best.

P.

Paul, please explain the whole "SAE corrected and standard corrected" situation. I know corrections are made so that different pulls at different altitudes can be compared but that's about the extent of my knowledge on this. And I'm not even 100% confident I'm correct on that!

[Nacho_ZR1]

Going from a steel flywheel to an aluminum one is most of it.

The steel flywheel weighs that much??????

[Fully Vetted]

Paul, please explain the whole "SAE corrected and standard corrected" situation. I know corrections are made so that different pulls at different altitudes can be compared but that's about the extent of my knowledge on this. And I'm not even 100% confident I'm correct on that!

Actually, I'm sure several can explain this. The floor is open...

[Pete]

The steel flywheel weighs that much??????


Stock flywheel is 36 lbs, aluminum is 13.5lbs almost 23 right there.
Spare tire and tools 50lbs.

http://zr1specialist.com/HAT%20Web/Tech%20Info/Weight%20Reduction.htm


Pete

[Pete]

Pete, did you do the lightweight pullies on my car or is that something Michael did after you worked on it? I'm trying to determine if your 425 number was done before or after those were installed.



I think he did the pullies afterwards they are not my pulley design,the older pullies were a bit too heavy for my taste LOL

Don't chase dyno sheet #'s if that's all you want i can give one just tell me what #'s you want.LOL
Like i mentioned before all dyno's are different i used to go 3 different dyno's and all were different but withen 10rwhp one was way out there low about 30,i'm sure if i droped off a few stacks of cash they would get me 30 lol
This why i say 420-430 is withen tolerance.
My Z did 466 on one dyno and 474 on another which do i believe,of course i will post the higher # :-)
Dyno's are tuning device/tool.

Pete

[Paul Workman]

Stock flywheel is 36 lbs, aluminum is 13.5lbs almost 23 right there.
Spare tire and tools 50lbs.

http://zr1specialist.com/HAT%20Web/Tech%20Info/Weight%20Reduction.htm


Pete

Yep. The rotational mass difference has been demonstrated to be the equivelant of ~ 15 rwhp on an inertia dyno comparisons. Might be worth an tenth or so off the 60 foot times, ya think?

[Nacho_ZR1]

I think he did the pullies afterwards they are not my pulley design.Pete

So do you sell lightweight pulleys or have a source that does? I'd like a set:fahne:

[Hib Halverson]

Wel now... that IS the question.

It seems SAE standards evolved over time, introducing the oppotunity for different results for the same run, depending on which "standard" was applied. Add to that some calibration issues, and operator's attention to detail.... Makes for ambigeous results at best.

P.

That is not correct.

SAE Standard J1349 has existed for decades and is still used today. Virtually all chassis and engine dyno operating software corrects to both "standard" and SAE. Some also correct to various DIN standards, as well as the JIS standard.

The difference between "standard" and "SAE" is the atmospheric conditions to which the dyno data is corrected. The makers of aftermarket performance enhancments like "standard" corrected because it typically makes for "bigger" number. Engineers always use "SAE" corrected because the SAE J1349 standard specifies an atmospheric correction factor that is more "real world".

The executive summary of the two atmospheric corrections is: "standard" considers that the engine was run on a 60°F day with 0% humidity and a barometric pressure of 29.92 in-Hg. SAE J1349 considers the engine run on a 77°F (25°C) day with 0% humidity and a barometric pressure of 29.234 in-Hg (99 KPa).

How can these two standards affect dyno results., during a recent chassis dyno test I did with a 2012 Z06, if I correct the data to standard, the best of four passes was 473 at the wheels. If I correct the data to SAE J1349, it was 454.5 at the wheels.

[Pete]

So do you sell lightweight pulleys or have a source that does? I'd like a set:fahne:

Yes,i do sell them.
Email me if your interested petezr1@gmail.com

https://sites.google.com/site/peteszr1garage/


Pete