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Discussion Starter #1
Just came in from first drive with Blackwing installed. I did not put many miles on it, maybe 30. The feeling when driving is that the engine spools up faster than before, I am not sure when I should see a hp difference. I was told 50 miles. I am not feeling a loss of power at all. Trying to get back to the Dyno.
 

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Hey 02!
When you do get your Z to the dyno, I'll be very interested to see what kind of numbers you get. I put the Black Wing on my '02 with 28 miles on it, and now have about 180 miles on the car. I've been worried about the reported hp loss ever since I heard about it.(about an hour after I got the thing installed) Supposedly the loss is above 5800rpm. Let me know what you find out.
Thanks.
 

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30lb injectors

You will lose about 20 horsepower up top, that was the first mod i did to my car, best mph with the blackwing 114.75(12.54)-with the stock box 118.87(12.35). The LTFT will go up to 15-20% and the injectors are too small to compensate. The car will run lean by 15-20% under normal conditions then 15-20%rich at the top end. The backwing is a awesome piece it's just that these 02's are so tweaked you upset the balance of the car with small changes. The best thing to do is add 30lb SVO injectors( about $220)-this will bring your LTFT's to 0 and you will gain 20hp up top over stock. Cut a hole in your shroud under the blackwing to allow some cool air in-this will lower your air temps by about 20 degrees giving you more timing also-you don't need the cold air box to see this benefit-enough air flows through under the rad cavity and no need to worry about water ingestion.
 

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Discussion Starter #4
Thanks for the info. I am still holding out that this is only a selective problem, but it doesn't look good. Is this occuring only at top end or the entire hp curve? Do you gain any power below 5,800 rpm? I will not see those kind of r's on street use.:-?
 

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LTFT's

This is something I learned from TeamZr1. The donaldson flows so much air that the LTFT's go from 0 to 15-20 which it figures out during mostly city driving. the injectors are too small on these 02's to bring them back to 0. So when we go ito full throttle the computer multiply's 15-20% of the LTFT's to the WOT map and you have a pig rich condition. Yes this will also affect city driving or areas under he curve as timing is reduced when the LTFT's go past 0 to 15-20%. with the 30's the LTFT's will go to zero and if you use the maft you can fine tune the final wot map to get almost 32 degrees total timing on top. The track is done for me up here but as soon as April rolls around I will be testing this and fully expect to run 12.0'[email protected] on the factory radials. Now if I can only get my 60fts down to 1.8's this thing should run in the 11's. 118-119 mph are Viper territory and that's even faster than the 415 horse 911 turbo. It took me a while to figure this out but Jim said a long time ago that these injectors are undersized.
 

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Vortech,
Where did you buy your injectors? That sounds like a good fix. How tough are they to put in? I don't want to mess with the MAFT (I have no lap top and am an idiot!:lol: ) so down the road when I get my headers, X-pipe and PRT's put on, I was going to have my computer done. What do you think of the aftermarket MAF's out there, can they help this situation if you don't want to get into all the MAFT stuff? Thanks for the great advice!!:cheers: I'll cut out the shroud this weekend!!
Take Care,
 

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I was under the impression that the MAFT could correct for this. But I guess if the injectors have run out of steam, that won't be the case.

My copy of EASE PC arrived tonight. But still no Z06.. :lol:
 

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Z06 Tom

You can pick up the injectors almost anywhere they sell mustang parts-pick up any musclemustangs and fast fords magazine and there will be about a million venders selling them for around $220. They are a sinch to install-go to the corvetteforum.com and look in the tech tips-you'll find a install article or check out vetteguru.com as well. If you can talk to me on this board then you can use a autotap or scanease no problem. This will be instrumental to getting your car to peak perfromance. The MAFT rocks-you can adjust it anytime you make changes without sending your computer away for an expensive retune-those in my opinion are for big cams and stroker motors or when you've added say another 100 horse over stock. Good luck!
 

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vortech ,

Do they make a different MAFT for the Z06 , or is it just the regular LS1 version? I thought that the Z06 MAF was wired differently than the regular LS1 MAF.
 

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MAFT

No they don't make a Z06 specific MAFT yet. I haven't bought one yet as I will be putting the car away in a few weeks. we have to use the MAFT from the LS1's and hardwire it in-meaning cut and splice. I don't want to cut my MAF harness yet so I am waiting to see if they will come out with a unit with the right plugs for our car. If they don't well then in the name of more power I will cut it.
 

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I think SLP offers the Z06 MAF for the F-bodies and it comes with a harness that allows you to plug the Z06 MAF right in. I wonder if you could just use two of those harnesses (one on each end of the MAFT) and then be able to plug the MAFT in on our cars. I would prefer not to cut up the wires on my car too.
 

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I don't think it will work

Butcher I seen the SLP piece but it will only work going into the MAFT and going back ito the factory harness-also we need to wire up the IAT sensor as it is seperate on the older MAF. By the way those are awesome times buddy! 117.61 mph makes me even wonder if a aftermarket setup would improve on this-have you checked your LTFT's with the K&N. With my cut stock box they are about 4-5% which means my car is about 4-5% rich on WOT.
 

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Vortech,
If I go with the 30lb injectors alone, will this negate the hp loss with the "Black Wing"? I will get into the MAFT in the spring, but for now I just don't want to loose 20hp right off the bat. :-? I'm going to cut out my shroud as you suggest, would you cut the hole the same size and in the same location as the "Black Wing"? I had been kicking around the idea of putting a screen over the hole I cut to filter out some road crap and keep the air filter cleaner. I thought I would just use window screen. What do you think of this idea? Thanks for your input!:cheers:
Take Care,
 

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Good idea!

the 30lb's alone should negate the loss with the blackwing as they should push your LTFT's to 0 versus 15-20%. The MAFT just enables us to finely tune the combo and get a more aggressive timing table for a few extra ponies. It also helps at a later date when you say add headers or a off road pipe. You can keep adjusting for the changes with the MAFT instead of sending the ecm for a reprogram. The idea of the window screen is excellent-it will trap any bugs and road debris that try to get in-just lookm at the rad. Another thing to consider is getting a 01 MAF with the screen. There is no loss in power with the screen and the screen does enable to MAF to get a more accurate reading. I can get the 01 meter's for about $100-call your dealer to find out part#25318411.
 

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vortech ,

I checked my LTFT's and they are at +5-6. My car ran very rich when it was completely stock. I've got a Halltech T1 on the way , so I was going to order a set of 30# injectors. Then it hit me , has anyone dynoed their car with this condition before and after they installed the injectors? Not only to check for HP gain or loss , but also to check the air/fuel ratio. I'm curious because I think that the computer is programmed to run the car at a certain air/fuel ratio. If you install 30# injectors the LTFT's will go back to zero , but you now have bigger injectors that will inject more fuel at the same pulse width and pressure. Whether it's +5-10% with the stock injectors or 0% with the 30#'s , it's still the same amount of fuel over all. Right? Maybe I'm wrong , but I think that unless you change the computer program or fool the computer into thinking that the car is running too rich , nothing will change.
 

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Discussion Starter #16
Check out the the transscripts of the teamZR1 chat about all these things, MAFT, injectors and Ease computer. I read them last night and got a crash course. I feel informed enough to make the corrections and understand the whole MAFT, lean\rich problems. Wether you go with the Halltech or the BW, the MAFT and the injectors will benefit you greatly. The idea behind the injectors is that they will not have to work as hard to get the proper AFR. The more air to your engine the leaner it will become, thus the stock injector has to work @90% duty to try to even out 0. anyway if you give me your email address I can send you the transscripts, I learned a lot. Last time I tuned an engine HEI was the biggest thing and heads, cam and compression where all it was.
 

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30lb injectors

02Z06 is right-these injectors are just too small to compensate. i beleive the 0xygen sensors in these cars adjust pulsewidth of the injectors and insure the car is running clean. Right now butcher you probably won't gain too much from the swap to 30's-the MAFT is probably all you need-once the T-1 goes on I bet the LTFT's go up to about 15-this is when the 30's will help. I wish I could see a bone stock 02's LTFT's i bet that they are around 2-looks like GM made the car run lean under normal conditions and then rich under WOT so we don't melt pistons. I never would of thought the K&N flowed more than the stock filter-especially when it's cut open. I wish I lived in Texas or Florida so I could test all year round-I have to wait until April to see what the 30's MAFT and the blackwing or T-1 will do. A while back there was a problem oabout surging on a 01 car with the tric-check out what TeamZr1 did to fix it. It should still be on of the pages in this pit road forum.
 
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Good to see people really starting to think about tuning and understanding they do have a path to correct AFRs that are detuning their performance.

For one, my '99 was ill tuned with some custom PCM code,
car was running +10 ( which means lean) LTFTs and that was in winter weather.

With the SVO 30s, MAFT and the Ease scanner, my before dyno at rear wheels were 385 HP at 360 lf/lbs torque. These results repeated on another dyno day a month later.

Lean condition drove ping, which lowered WOT timing, which kills torque.

After installing SVO 30, tuning via MAFT, on the same dyno machine, after results are 410 HP at 400 ft/lbs. these results also repeated on another dyno day about 6 weeks later.

By proper tuning AFR to meet my conditions ( biased tuning to be ping less at WOT) took WOT timing from about 23 to 28 fegrees, which is a good kick in the butt for torque.

Your using about the same amount of fuel ( got a bit better MPG with SVO 30s) but your tuning PCM to pretty well stay around perfect LTFT so PCM is not fighting a lean condition all the time and forcing longer injector pulse widths and also focing coils to be pushed at their high end.

Remember, even if your C5 is stock ( esp 01 and 02 MY) the PCM is biased to EPA/CAFE and AFR tends to be on the lean side, thus to tune using stock injectors ( worse for those of us with '99 and 02s with smallest stock injectors of C5s) you have to force PCMs to go even longer pulse widths, richer means less timing.
Thus by going with the larger injectors, you are now biased rich and are dialing in with a MAFT to tell PCM to go leaner, less load, higher WOT timing.

PCMs were designed for emission watchdogging, not to do some automatic performance tuning on its own.

butcher said:
vortech ,

I checked my LTFT's and they are at +5-6. My car ran very rich when it was completely stock. I've got a Halltech T1 on the way , so I was going to order a set of 30# injectors. Then it hit me , has anyone dynoed their car with this condition before and after they installed the injectors? Not only to check for HP gain or loss , but also to check the air/fuel ratio. I'm curious because I think that the computer is programmed to run the car at a certain air/fuel ratio. If you install 30# injectors the LTFT's will go back to zero , but you now have bigger injectors that will inject more fuel at the same pulse width and pressure. Whether it's +5-10% with the stock injectors or 0% with the 30#'s , it's still the same amount of fuel over all. Right? Maybe I'm wrong , but I think that unless you change the computer program or fool the computer into thinking that the car is running too rich , nothing will change.
 
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