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dyno results on the super nat 475.....

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bradslt5

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stopped by a buddies shop so we strapped the wifes just bought callaway super nat 475 zr1 on it to she what she did. made 3 pulls ,first one 289.rwhp and 300 tq . wtf , opps forgot the power key (crs) and the next 2 were 373.84 rwhp and353.64 tq. car is as delivered from callaway except for corsa exhaust . if someone who can post the sheet for me also has a fax number give me the number and i will send it to you to post for me . know i got to find a set of headers. deb was pleasenly surprised at the power .but is too preggers to drive . oh well guess i will just have to drive her around :chuckle
 
373 at the wheels is about 450 hp at the flywheel, IF the rear wheel figure is SAE Net.

So, you're down about 25 hp from where it should be. How many miles are on the engine since Callaway did the conversion?

You should be in the 390s, if that engine is performing to its original intent.
 
hib there is 40k miles on her . i kinda wonder about the injectors if they are getting ugly .prevoius owner replaced one injector and 1 plug wire . the other 2 zr1s i have didnt really run right until i replaced the injectors with rcs . i have ordered a set for this car also . plus in cking last night when i got home there is a secondary vaccume leak under the plenum . kinda thought there was due to the second run made power alot earlier but was about the same hp . something else interesting is the cross counts on my scanner while cruizin on the freeway are very slow could be the o2 sensors seem slow so i may need these also . although i dont think they effect wot. this car also doesnt seem to activate the knock sensor llike the other 2 cars . could be bowlshaping during the porting process at callaway or the knock sensor is too tight .but having only owned the car for a week I am sure i will find things here and there . but with twins on the way moving into our new house and grass starting to grow on the course ,and teaching the golf team, i need an extra 10 hrs a day . all in all she is in pretty darn good shape and the price was right also . soon as i can get my wayward adopted son to come over i will get picks for you guys .if someone can give me a fax number i can send the dyno sheet so they could post for me .
 
on the milage since the converson there wasnt any milage on the callaway invoice . it was dated july 8 1993 and going from the other dealer invoices for other things right after that . the conversion was done at aprox 11200 miles . so there is about 29k on the conversion . the air fuel on the dyno was about 12.5 which might be a little fat . plan on doing a plenum pull this next week to fix vaccume and ck out everything else under there .
 
If the secondary vacuum leak is preventing one or both secondary actuators from going full-open, that would, of course, decrease power. But, since you're going to pull the plenum, you can actually test for that with a hand vacuum pump like a Mityvac.

Restricted injectors could do that as well, but since you've got a new set of RC Engineering injectors coming, I'd not worry about that. Just put the RCs in. If you've not replaced the fuel filter within the last 25000 miles, I'd do that.

Lazy O2Ses should not impact power at WOT but they will decrease gas mileage, degrade throttle response and mess-up driveability. If you replace them, use Densos not Bosch or Delphi.

As for the knock sensor, what's your scan tester telling you as far as KR near peak torque?

Also, LT5s like about 95-oct to keep them out of detonation. What kind of gas were you running in the chassis dyno? Were you taking scan data at the time?

Leave your AFR at 12.5. Yes, it's a tiny bit fat, but that's good for cat protection. You won't gain much power going to 12.7 or 12.8 but you will gain exhaust temp.

Was the dyno data you posted SAE-corrected or standard-corrected?
 
deb was pleasenly surprised at the power .but is too preggers to drive . oh well guess i will just have to drive her around :chuckle


I can't help with your dyno numbers, but you are in good hands w/ Hib, for sure! :upthumbs

What I can tell you is that when my wife was 8.5 mos pregnant, I took her on Skyline Drive with about 130 other Corvettes. The Callaway SuperNatural held its own, and my wife ALMOST had her water break, or so she thought :ohnoes She felt contractions and everything. I say it was a Vetgasm, not early birth ;LOL

...she'd kill me if I posted the pics of her in the car, with child. Good luck with yours! :beer
 
SOMETIMES CALLAWAY USES HIGHER FLOW INJECTERS!
GIVE THEM A CALL JUST TO MAKE SURE!
 
the dyno was a dyno jet. it says uncorrected 29.87 in-hg, humidity 24%runtemp68.94. hib thanx for the heads up on those items . dumb me totally forgot about the fuel filter . also i have 2 sets of msd wires .so one can go on her . i have allways used bosch 02s but i think i will try the densos . what do you like better about them .. we did have the scanner on during and it never hit the knock sensor once . usually going uphill from ridgecrest i get 25-30 hits on the knock sensor doesnt take more than 1 deg out though . this car it only had 3 knock events . gas i used was shell premium unleaded . its that or chevron is all i use unless i go to the drag strip . then i try to mix 100 oct unleaded on a 50/50 deal . it will be interesting to see how its ported compares to the blk car that corey henderson ported . does any one know if this pkg is just a top end pkg or do they put in stronger rods pistons and low tension rings ? htanx for the help . i am going to staples tonight to try to get something to post pics and the dyno sheet . but then i have to figure out how to use it :D
 
Well, if the data was uncorrected, it's, for the most part, irrlevant.

I'd contact the dyno facility and ask them to use WinPep (Dynojet's software) to generate some results that are SAE corrected. If that pup is working well, you ought to be somewhere in the area of 390 SAE corrected. For reference, the Auto Masters Street Skinner engine I have in my 95 was up around 410-412 SAE corrected (on a Dynojet) which works to about 500hp at the flywheel.

The Denso O2S is a better design. I think, elsewhere on the CAC, is a product review. Also there's a similar discussion on a Camaro site at http://www.camarohomepage.com/project/part3.htm

When I run on the chassis dyno with my ZR1, I mix pump 91-oct with Rockett Brand 100 unleaded at 2:1. That's always been sufficient to keep the motor out of detonation.

I'm not a Callaway expert, but my guess is the Supernatural 475 was a 350 with a stock bottom end.

I'm surprised up in the Owens Valley your getting any knock retard. Clearly, whomever was calibrating Callaway's chips put a pretty aggessive spark schedule in there.
 
we get that junk winter gas . starting in april it changes . so says a friend that owns the local chevron .the dyno run was done in bakersfield / well actually buttonwillow raceway @ just 7s racing. on the top of the sheet it does say winpepbut says uncorrected . will call tomarrow and see if i can get corrected results . are the denso o2 sensor avail at most of the auto part stores . i,ll try to take some picks of the porting when i pull the plenum. whats a good digital camera to buy ? thanx again for the help:upthumbs
 
i,ll try to take some picks of the porting when i pull the plenum. whats a good digital camera to buy ? thanx again for the help:upthumbs


Re: cameras, most point and shoot digital cameras are easy enough now to use. 5-7megapixel camreas are the norm now. Best to look for ease of use and user firendly features for transferring your pics to your pc.

Once stored on the pc, you can follow this link on how to make them an attachment in your post. I hope this helps :beer

Link: http://www.corvetteactioncenter.com/forums/showthread.php?t=92568
 
thankyou somuch for the info we will know soon if i am a complete dummy!hehe
 
big john where can i go to find out what they did ? this is going to be fun learning about this car a the work callaway did . thnkyou for the info.

THE DIFERANCE BETWEEN A SN475 AND SN490 IS THE BIG CALLAWAY HEADERS.
MAYBE "89X2" (CHRIS) CAN LOAD THE CATALOG PAGES FOR CALLAWAY LT5.
:ugh
 
thanx for the info , boy i am really enjoying this car . but I am getting dirty looks from my bride , i did buy it for her . so i guess its time to mod the suspension in my black zr1 . the super natural pkg is very well thought out and a great used car buy. and the guys on this site ,very helpfull,and nice too a new guy. i might just have to look for another one , but i have dreams about a 415 zr1 .
 
If that pup is working well, you ought to be somewhere in the area of 390 SAE corrected.
FWIW, I believe Callaway dyno's their packages on an engine dyno, not in the car. I'm not sure anyone really knows what flywheel numbers should work out to what at the wheels. Perhaps 475hp = 375 on a dynojet. Or perhaps his car isn't running 100%. Or perhaps the 475 was generous. Who knows.

It would be nice to have some body of numbers from these cars. Though I can't recall seeing any dyno nor 1/4 mile numbers for any Callaway ZR-1's, except those published by magazines. It would be especially interesting to know what these cars throw down on the rear-wheel dyno because they have engine dyno sheets.

The links Chris put up, as well as ones that describe the whole package, are great reading. Callaway did touch the bottom end, though the cars are still 350ci motors.

This basically describes the package. The 475 package was this but without the header/cats and supernatural exhaust. I believe everything else was included (engine work, flywheel):

http://callawayownersgroup.com/Images/supernatural/s2.jpg

I'd imagine they used stock injectors, because they flow enough to make way more than 490hp. Though I have never owned one and don't know that for sure. But on my car which makes about the same whp, the injector duty cycle at WOT at 7k rpm is only like 55%. They have a lot of room.
 

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