Some recent dyno graphs

[Aurora40]

I dyno'ed the car this weekend on a SuperFlow dyno. Nothing changed since the last time, but I was interested to see it on the same dyno as I'd done other baselines.

Long story short, it peaked about 372hp. On the dynojet at Marc's it was 383hp.

Here's the gain from a ported top end and exhaust to adding headers and Marc tuned it:

http://hometown.aol.com/CorvetteZR11990/exhaust/headerdyno.jpg

The car always has some spark retard on the dyno because I don't get to WOT it on the way there much. If they did a few more pulls it probably would have gone away. That's what I see on the street/strip too, the first few have some KR, but it goes away. The gain at the peak was about 21hp.

Also we ran the car with the key off. Here's the full power vs normal power graph. The power peaks at about 225hp.

http://hometown.aol.com/CorvetteZR11990/misc/keyoff.jpg

[902066]

When most people say "ported top end" that usually includes porting the heads. That is not the case with these #ers is it?

[Kevin]

top end is plenum and injector housing in our ranks 90. Top end/heads is both

[HIZNHRZ]

Hey Bob, how's it going. Did you run your car on Tonys dyno? 370+ rwhp from stock displacement and headers is a heck of strong running ZR1!

I'm still going through ZR1 separation anxiety. Should be over it soon. I'm thinking I'll be heading out to Chicago in the next month or so...
If you remember, just after the new injectors I took my car to Marcs. I never did anything with the LT5 ODB scan tool you showed me. When I drive home I'd like to be able to baseline my cars performance. Would you mind giving me a list of what I'll need to have with me for when I get my car? If you have the time, would you mind going over with me how I'll need to go about hooking it up for the ride home?

Thanks.

[Zr1 Destroyer]

Not bad for just opening the plenum and IH's.......easy/free horse power in my book!:dancing

[Aurora40]

Yeah, "top end" means plenum and IH's. Not the heads.

Scott, yeah the dyno was at Tony's. That's where I'd had it dyno'd with just the porting, and then with the porting and exhaust. So I was curious to compare now with that vs the dynojet number in isolation. I'd be glad to help you out with the scanning. I don't have time right now, but I'll shoot you an email.

I thought the key-off run was interesting. I wonder how the curve compares to an L98. The hp peak seems similar, though the torque doesn't fall off as badly (but perhaps doesn't have as high to fall from).

[XfireZ51]

Not bad for just opening the plenum and IH's.......easy/free horse power in my book!:dancing

Having just finished porting 16 plenum runners, 16 IH runners and still staring at doing a minimum of 8 cylinder head ports, not sure how free and easy those extra ponies are. :sign10: However, I am sure they will be worth every hour!

[bradslt5]

what exhaust did you have behind the headers ? running these cars on ther dyno allways send chills down my back as they sound so sweet at 6-7k . now the 410 gears and the fidanza flywheel .gets one even more fun

[Paul Workman]

Very interesting!! the increased area under the curve is what is really impressing me, along with how flat that torque curve got! Hp is climbing all the way to the "edge of the map" - which makes me wonder how much more might be had if the rev limiter was pushed out a couple more ks.

Bottom line...The changes didn't just result in some peaky "improvement" (of the kind we usually get treated to when someone is selling 'bolt on horsepower'), but real across the band increase and coupled with flattening too is just so much frosting on the cake.

I'm REALLY stoked now! I've waited all winter (still waiting, actually) to drive my "new" Z, but my project for next winter will be a "PHASE I" - top end, headers and Pete's B&B type exhaust, 4.10s, and a Mark H. tune. Mebby I'll do the heads the following winter.

Thanks for the graphs. That seals it!

P.

[XfireZ51]

Too bad you didn't have a WB O2 hooked up. Interesting how the torque peak was extended to ~5500rpm and HP ~ 7000rpm. Anybody know if they'll have a dyno at The Gathering?

[Aurora40]

what exhaust did you have behind the headers ? running these cars on ther dyno allways send chills down my back as they sound so sweet at 6-7k . now the 410 gears and the fidanza flywheel .gets one even more fun
Exhaust is stock pipes, LT4 resonator, and Dynomax 3" Ultraflow SS mufflers. I thought it was neat to hear it driving from the outside. A nice sound, not too obnoxious. Too bad it's so resonating on the inside...

Too bad you didn't have a WB O2 hooked up. Interesting how the torque peak was extended to ~5500rpm and HP ~ 7000rpm. Anybody know if they'll have a dyno at The Gathering?
There was a wideband hooked up. It just makes the graph look odd. I'll post up a picture with it.

Edit: here's the picture:

http://hometown.aol.com/CorvetteZR11990/misc/dynowb.jpg

[XfireZ51]

Interesting that even with headers WOT is rich. You could get some more hp by bringing the AFR up into the high 12's from what I've been told.

[bradslt5]

wow the afrs are way rich .comared to both my cars .the callaway which i just did which is ported snat 475 . i dont know how agressive it is . but pete (who'd know ) said it was mild .did 372.84 rwhp and 353.64 tq the air fuel started at 12.9 @2500 and went slowly to 12.7 @6600. do you still have the factory injectors ?. or was you knock sensor pulling out timing ? that could be the reason for the spikes .. there is a way to really take a bite out of the resonance .heres what i did i got some sheet aluminium and and made a shield for the mufflers . if you have a fax i could draw what i did . i no longer need advil; for my headache . i know what you mean about hereing her on the dyno . just plain music to my ears . only trouble is ya got the mod bug now . i think petes ported stk blk makes 450 rwhp . thats just about right without having to go nuts money wise .have fun . get some extra toothpaste for this :mrgreen:

[ZR1Vette]

Anybody have a dyno run on a total OEM set up ZR? Mine is stock except a Haibeck chip and be curious to compare. I will be taking mine up to Tony's sometime this year to do a run or two...
Michael

[Kevin]

if you have a dyno of your car Michael it'll be close enough to stock. the chip doesn't add that much to the car that it will vastly alter the output

[A1990]

wow the afrs are way rich .comared to both my cars .the callaway which i just did which is ported snat 475 . i dont know how agressive it is . but pete (who'd know ) said it was mild .did 372.84 rwhp and 353.64 tq the air fuel started at 12.9 @2500 and went slowly to 12.7 @6600. do you still have the factory injectors ?. or was you knock sensor pulling out timing ? that could be the reason for the spikes .. there is a way to really take a bite out of the resonance .heres what i did i got some sheet aluminium and and made a shield for the mufflers . if you have a fax i could draw what i did . i no longer need advil; for my headache . i know what you mean about hereing her on the dyno . just plain music to my ears . only trouble is ya got the mod bug now . i think petes ported stk blk makes 450 rwhp . thats just about right without having to go nuts money wise .have fun . get some extra toothpaste for this :mrgreen:

Take a picture and post it.

[Aurora40]

do you still have the factory injectors ?. or was you knock sensor pulling out timing ? that could be the reason for the spikes ..
The injectors are new Delphi '93+ injectors. Yes some timing was pulled. I mentioned that in my first post. The car seems to carbon up easy, and the first few hard pulls tend to have KR. You can see it in the graph. It was worse in the 1st run. It probably would have been gone if they did a third pull. I see this at the dragstrip too.

Michael, here's one of my car all stock but ported on the top end. I didn't dyno it when it was stock. Phil dyno'd his stocker, though he has a '94.

The bottom line is the just ported one:

http://members.aol.com/corvettezr11990/exhaust/dynocompare.JPG

[karterdon]

Dyno pulls will be avail at BG 8,9 &10 - You need to register. They will also ues a WB 02 sensor - but that is extra.

[XfireZ51]

Dyno pulls will be avail at BG 8,9 &10 - You need to register. They will also ues a WB 02 sensor - but that is extra.

Don,

Hope to have my own WB hooked up by then.