Performance Upgrades

[ralph92ZR1]

Not wanting to be foolish with some Xmas monies but no better place to spend than the ZR-1 so here goes [2 ] questions :icon_ques :icon_ques for the group on upgrades for my '92 ZR-1:
1. In Carlisle with the "hoods up" I saw several with the triple air intakes with high flow K&N filters. A manufacturer states up to 20 HP gain depending on application. Thoughts Please.
2. In the forums, which by the way are fantastic, and offer so much information I have noted many using the Haibeck performance chip. I did a little research and all the info seems well documented. My question is really on the "knock" sensing or reducing false knocks by 50 %. Over time I am told that engine knock can really do damage. I would like to hear some comments on this aspect of the upgrade [engine calibration] by members who have upgraded to such a chip.

I read the threads on porting, etc. and those options are out of my budget anyway $$$.
Thanks and Happy Holidays !!!

[A1990]

The chip is a pretty good investment and Haibeck is one of the best. Most don't invest in the triple intake, most go with K&N and possibly an open lid. You should also make sure that your air duct is not collapsing. Older stock ducts tend to do this under WOT.

The 20HP gain, well that is marketing. You would have to couple that will other mods to get that kind of gain. A free-flowing cat back exhaust is your best bet for quick bolt on HP gains.

Look for group buys on B&B or Corsa and if you can do the work yourself, a chip the open lid and a good exhaust should be worth 20-30 rwhp

[secondchance]

by members who have upgraded to such a chip.

It is my understanding that knock sensor mistakes shifting as engine knock - henceforth "false knock".
Haibeck chip in essence eliminates this misinterpretation.

This may help.

http://www.zr1specialist.com/HAT%20Web/presentations/Calibrations.pdf

For further discussion, you might give him a call.

FYI. I switched to his chip about a month ago and the car runs cooler and stronger not to mention annoying 1-4 shift light being turned off and never having to worry about not having the power key turned on when encountering pesky wannabes!:mrgreen:

[Paul Workman]

Marc Hiabeck's web page contains a good amount of info, w/ regard to what performance gains can be had and approximately the order that might make the most sense, especially if doing it in a staged approach:

http://www.zr1specialist.com/HAT%20Web/products/major%20engine%20upgrades.htm

Note especially the top end porting at the bottom of this page (C-link). I point this out because this is a big performance item that you may want to consider doing yourself. Coupled with Marc's chip also provides cooling fan control, the Full Power is always on, the knock sensor modification, anti-backfire thru headers, a slight timing increase, the CAGS 1-4 shift is gone; optimizing for 93 octane, and additional fueling to accommodate the mods and hp. Mine seems to do all that.

Headers (Stainless Works is about the only one making them for the ZR-1 now), and an open exhaust system and you will pick up some serious power. As for that tri-thingy I had one on my LT1, and aside from looking spiffy, it didn't do a thing more than a cut lid intake.

Anyway, Marc's web page pretty well spells out the "real deal" as far as what to expect from the various mods that really DO improve performance.

P.

[Locobob]

You won't get anywhere near 20hp from an air intake, from one of my old Corvette Forum posts......


Today myself and forum member/dyno owner TJ Wong set out to find the truth regarding C4 air intakes. We dyno tested 3 different air intakes on my Lingenfelter 368cid LT5. Tested today were: stock with paper element, stock with K&N element and a cut lid, and finally SLP's "claw" tri-cone filter design. All dyno pulls were made with starting coolant temps at 195 degrees F. Here are the results.

Stock with paper, two identical pulls: 477rwhp. Avg. peak HP 477

Stock with K&N and cut lid, three pulls: 471, 475, 480rwhp. Avg. peak HP 475.3

SLP tri-cone "claw", three pulls: 477, 478, 481rwhp. Avg. peak HP 478.7

It would appear that the naysayers are mostly correct about C4 air intakes, not much to be gained here. Both Tom and I were rather suprised with the results. We had expected to see some small but visible gains with the cut-lid and SLP, instead we got a bunch of tests with peak numbers being basically the same or well within normal dyno pull to pull variation. The SLP unit does seem to have a small advantage over the others but suprisingly it's in mid range power not peak (see dyno graph average power #'s).


http://www.pnwzr1.net/Robert/368dynoairintakecomp.jpg
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[bobbyhi]

Very interesting Bob.................

[Jason 91]

I have always wondered about the gains on the various air filter options given the claims. Currently, I have a K & N and that is probably the most I will do at this point after reading this.

Thanks,

Jason

[Zr1 Destroyer]

I have always wondered about the gains on the various air filter options given the claims. Currently, I have a K & N and that is probably the most I will do at this point after reading this.

Thanks,

JasonJason, did you also modify your filter lid?

[Jason 91]

Not yet. That is the one thing I will probably add to the K & N in the near future.

Jason

[Aurora40]

FWIW, I compared the stock box with a cut lid and paper filter to the SLP intake. I measured the pressure drop at low rpm WOT vs max rpm WOT as fed back by the MAP sensor. I made three runs in 3rd gear with each.

I noticed on average about a 1 1/2 kPa difference in terms of average drop, with the SLP having less pressure drop. Assuming the temp and such of the air is the same, that would maybe be like 4hp at most? At that, the SLP still drops about 2kPa from low rpm to max rpm. I'd guess that this would happen with no air filter, that there would be some increased pressure drop as the rpms get higher no matter what.

There certainly aren't huge gains to be made in the intake. But the SLP is a nice unit, looks nice, and is easier to take in and out. I sorta wish someone made paper cone filters though, as I hate cleaning K&N filters.