I would like to know what track times people are getting with the ZZ502 and and what elevation the track is.

I'm very dissipointed with our ZZ502 so far and I'm wondering if I was expecting too much or something. The best so far is 13.11 @104 with 1.8 60' foot times. I was expecting low 12's @110 plus.

My 5800lb Yukon 4x4 runs 13.6 @100 at the same track.

Thanks,

Lee

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1967 ZZ502 Camaro <A HREF="http://www.1967camaro.net
1970" TARGET=_blank>http://www.1967camaro.net
1970</A> ZZ502 Chevelle http://www.1970chevelle.net

Well, that isnt too good of a mph, looks like its just not making the hp. Whats your timing set at, or do yout have the Holley EFI on it too, I couldnt help you there, I'm sure you know more about that then I do. What about the exhaust? People seem to choke alot of bigblocks on the street! You will need 2" header plus a 3 1/2" system with some good high flowing mufflers, Atleast a 3" system. I use the Hooker 3 1/2" aerochambers with an H-pipe, they are way quieter then flowmasters. What about traction? But even if you were spinning you should have pulled some near 120mph. My engine wasnt a crate so I cant tell you what it should run, but 500hp should pull around 120mph in a street car. What kind of stall do you have? Something is just out of wak, its either the timing, fuel or exhaust. If its carburated you should have a 850cfm or bigger. Let me know what you think it is, look the car over http://www.camaros.net/forum/smile.gif Oh yea, I think someone around here has a couple of 502 crate cars, I'll try to find out what they run, I would think atleast high 11s even in a chevelle.

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67RS STREET CAR, 502 PUMPGAS, HYD. ROLLER, TH350 w/ATI 10" 12-BOLT w/373 - 10.92@125.2 ON MOTOR, ET-STREETs w/MUFFLERS

[This message has been edited by 67RS502 (edited 08-09-2001).]

67RS - The timing started off at 36 but the last run I bumped it to 39, I picked up et but not mph.

I do have the Holley EFI.

I have hooker super comp 2" w/3.5"collector down to 3" with H pipe into the hooker aero chambers and 3" all the way back. BTW, the aerochambers are real loud and was thinking about changing them!

Very little tire spin noticed, with a 1.8 60' time.

The stall is tight at 2400, I wanted good street manors and mileage. The rear gears are 3.73 with 28" slicks.

Drag2000 was predicting 12.0's at 111.

My O2 readings are from .780 to .840, .820 to .840 through 3rd gear. So I think that the fuel mixture is correct.

Thanks,

Lee



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1967 ZZ502 Camaro <A HREF="http://www.1967camaro.net
1970" TARGET=_blank>http://www.1967camaro.net
1970</A> ZZ502 Chevelle http://www.1970chevelle.net

Well dual 3" exhaust is good for 450HP so it should be OK. Your not going to find a quieter good muffler, the only one I can think of is the Dynomax, but it make 2~180 degree turns inside - so its not the best design. Do you have a mandrel bent exhaust system? If is a cheap kinked up POS - you need to fix that first!
Timing seems a little high, these big torque monsters dont like alot of timing. Try 34 or 35. My car made its best pass with only 34 total. If its computer controled can you see where it is @ WOT?
Your stall and gear are fine, Thats all I run is 373 and a 2500 stall, these thing dont need alot of gear ether = street car right!
Also it should 60' better, like low 1.60s Do you have any suspension work?
Just to give you an example, (I think I've posted this before) My buddy's got a sweet 70 chevelle, it a real SS car, its all stock/original - except for the engine and exhaust. Its got a 454, solid roller 250s duration, oval port heads, RPM intake , 850 Holley, 2" headers - 3" exhaust, 10" TCI 3500 stall, 373 gears. Its 3900lbs with him in it and has gone 11.50s @ 115 so far, and we're not done yet, shooting for low 11s.

I say put a cam in it http://www.camaros.net/forum/biggrin.gif That will pick up the HP and MPH!

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67RS STREET CAR, 502 PUMPGAS, HYD. ROLLER, TH350 w/ATI 10" 12-BOLT w/373 - 10.92@125.2 ON MOTOR, ET-STREETs w/MUFFLERS

67RS - The exhaust is from Torquetech and is mandrel bent.

The timing is computer controlled, so what I see should be what I get. Even if the timing is off a few degrees it wouldnt make up for a 1 second et loss!

The 1.8 60' is just stabbing it off idle. Now, I have to let you know this is my wifes car and she is doing the driving. We can record the entire run on a computer so I can see the rpm, throttle setting, O2's everything and she's shifting almost always at 5700RPM and it the 5800 rev limiter a few times. She has only made 8 runs at two events and has a lot of learning to do so I'm sure she can get the 60' down a little.

Most people keep telling me to add timing, but at this stage I will pull timing to try and figure it out.

Our elevation is 4400 feet, am I expecting too much at this altitude?

Lee

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1967 ZZ502 Camaro <A HREF="http://www.1967camaro.net
1970" TARGET=_blank>http://www.1967camaro.net
1970</A> ZZ502 Chevelle http://www.1970chevelle.net

I think changing the timing(pulling it back) and changing your launch will get you into the twelves...

I'd go with 34-35 degrees @ WOT like someone suggested already.

As for your launch, if your running slicks, and your heating them up properly first, I would say try stalling up the converter and launching @ 2400rpm instead of off-idle. *IF* the car hooks, it will pull better 60 ft times.

Oh, and the altitude is affecting things as well. I would think those times are good for atleast mid-twelves at sealevel. So for a rookie driver, she's not doing too bad.

Good Luck,
Joe

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92' Laser RS-T- 14.2@103mph
79' Z28 Camaro- coming soon :)
Boycott Lapeer Dragway

I want to know how your Yukon is running 13.60's at 4000' (or sea level for that matter). That must be one heavily modified truck!

Jody

CAMCOJB - Just a blown 350, here is a link with some movies running 13.9.
http://www.blown4x4.com

Since then I'm now in the mid 13's using 4x4 mode when launching with 1.9 60'. I installed an MSD RPM activated swith so that at 3500 RPM it turnes off the 4x4 mode! Works like a charm..

Lee

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1967 ZZ502 Camaro <A HREF="http://www.1967camaro.net
1970" TARGET=_blank>http://www.1967camaro.net
1970</A> ZZ502 Chevelle http://www.1970chevelle.net

That is too cool!!!!!!!

Jody

Which vehicle are you refering to...the Camaro or Chevelle? also what is your race weight with driver and track elevation?

Also, 3" exhaust is more than plenty for that engine HP. I run 3" pipes with 3" Straightline Performance mufflers and they do not slow my car down one bit...60's, 330's, 1/8th, 1/4 mile & mph were all the same with and without mufflers. This is with an ~580-600HP bbc.

I would venture to guess the stall might your problem. Is your converter an 10" or 11"? What does the converter flash to rolling at 5 mpg in high gear (then stomp it)? A cheap converter that slips a bunch or isn't tailored to the engines torque curve can really kill performance a bunch. I picked up 4 to 5 tenths with a converter change alone.

------------------
Malibumotorsports (http://www.Malibumotorsports.cjb.net)
79 Malibu, 414 ci BBC, 3550 lbs.
10.92 @ 122 mph, 1/4 mile
6.93 @ 99 mph, 1/8 mile
1.55 60'

[This message has been edited by Slowazzbu (edited 08-09-2001).]

Slowazzbu - I have the exact same setup for both the camaro and chevelle. The camaro is the only one done though so we are talking the camaro for now.

I got the 700R4 from bowtie overdrive and the owner convinced me to go a slighly looser then stock converter, so it's stock size and 2400 stall.

Looking at the data the Holley EFI shows, we either have a little tire spin exactly the every time or it actually stalls to about 2900 RPM, on every run the graph shows the RPM jumping to 2900 then taper a little then climb from there to the shift point.

We havent weighed the car yet but it's pretty much stock with a roll bar and traction bars, so i've estimated about 3800 with driver. The elevation here is a little more then 4200 feet, the temp was about 90, 30% humidity and about a 30 barometer.

Thanks for your help,

Lee

------------------
1967 ZZ502 Camaro
<A HREF="http://www.1967camaro.net
" TARGET=_blank>http://www.1967camaro.net
</A>
ZZ502 Chevelle
http://www.1970chevelle.net
13 Second Yukon 4x4
<A HREF="http://www.blown4x4.com
" TARGET=_blank>http://www.blown4x4.com
</A>

Your times of 13.11 @ 104 mph at 4200' elevation correct to 12.43 @ 109.7 mph at sea level. Altitude correction factors are available at www.prestage.com, (http://www.prestage.com,) car math section, NHRA correction factor link.

Also using Prestage.com's calculators...based on 3800lbs w/driver and 502 HP, the combination "should" be capable of a 13.00 @ 104.8 mph at 4200' elevation (figuring on 20% driveline loss = 400 RWHP). Their calculators have a +/- 5% accuracy. They also state that these calculations are most accurate when figuring on a drag type car with a well matched combination and no tire slip. Mild gears, tigh converters, etc, will produce slower times than predicted.

--------------
Malibumotorsports (http://www.Malibumotorsports.cjb.net)
79 Malibu, 414 ci BBC, 3550 lbs.
10.92 @ 122 mph, 1/4 mile
6.93 @ 99 mph, 1/8 mile
1.55 60'

[This message has been edited by Slowazzbu (edited 08-09-2001).]

[This message has been edited by Slowazzbu (edited 08-09-2001).]

[This message has been edited by Slowazzbu (edited 08-09-2001).]

Slowazzbu - The only real question/concern is why does my 5800 pound truck run mid thirteens? I have dynoed at 385 rwhp in 2nd gear, a third gear run should have netted 410-420 but the operator wouldnt run it in 3rd because of the tire ratings. Based on the rwhp I should have 525-550 at the crank. When I put the data in dyno2000/drag2000 the output is darn near exactly what I run in the qtr. So I drop the weight down to 3800 pounds to simulate the camaro and it predicts mid 11's. I then take off 50HP for the 502 and it predicts high 11's to low 12's.

There is a new dyno shop in town, I guees the only way to figure out what's going on is to do a wide band O2 test while on the dyno...

Thanks,

Lee

------------------
1967 ZZ502 Camaro
<A HREF="http://www.1967camaro.net
" TARGET=_blank>http://www.1967camaro.net
</A>
ZZ502 Chevelle
http://www.1970chevelle.net
13 Second Yukon 4x4
<A HREF="http://www.blown4x4.com
" TARGET=_blank>http://www.blown4x4.com
</A>

I read somewhere about a 502 that ran best with only 32 degrees total timing. As others stated, 39 degrees will be way too much. If I advance my 383 too much, my trap speeds drop (my little stroker mouse likes 33 - 34 total). With too little advance 60' times increase. Just watch the two and try moving your timing 2 degrees at a time until you find the sweet spot.

Also, a tight torque converter might hold you back more than you think. I improved from 12.8's to 12.4's just by changing my converter from a 2000 to a 3000 RPM stall.

Trying different tires may help too. You should be down in the 1.6's in the 60' times IMO.

------------------
68 Camaro, 383 small block with TH350 trans. 12.4's and never trailered.

I have noticed a few people telling you to go to a looser stall. I dont think you should do that, just look at our cars :
Both are 67 camaros, 502, 2500 stall, 373 gears, street cars! If any thing you would think my car would need move stall, but it didnt like it. I had a tight ATI 8" 3500 stall and the car 60' was 155, it was a little too much stall for a street car, so I went with a ATI 10" 2500 stall - 60' = 1.55 . It didnt help it 60' any better. I love my 2500 stall for the street. The only thing I would consider if I were you is the brand (quility) of your convertor! Is it made to take that much power? Is the tranny?

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67RS STREET CAR, 502 PUMPGAS, HYD. ROLLER, TH350 w/ATI 10" 12-BOLT w/373 - 10.92@125.2 ON MOTOR, ET-STREETs w/MUFFLERS

Glad to have you around here Todd!! http://www.camaros.net/forum/smile.gif

I believe Bowtie Overdrives uses TCS (not to be confused with TCI) converters. I have never found any info on them on the web. Todd or anyone have any knowledge on TCS?

------------------
...Dennis
'69 RS Convertible w/SS trim (http://www.camaroslimited.com/memberscars/den.htm)
'96 Z28SS #1679 of 2410 (http://www.camaroslimited.com/graphics/memcars/96ss.jpg)
"The Club" (http://camaroslimited.com)

Eric68 - I will certainly try lower timing since I've only tried adding timing.

I've been reading a lot about rotor phasing and it looks like this could certainly be a determining factor. It appears that I should turn the crank to 20 BTDC, align the reluctor in the distributor so that it's barely going past the center of the post and then look at the relation of the rotor post to the cap lug. When I do this the rotor is halfway to the next cap lug!

There was two articles that said if it's out of phase it could either backfire out the intake at high RPM's or just lay flat on power, I dont backfire so I'm hoping that this is the problem. I just picked up an MSD adapt-a-cap but the posts are different then I have now so the wires wont work :-( So I have to buy new ends and redo the wires.

Does anyone have any info on rotor phasing?

Thanks,

Lee

------------------
1967 ZZ502 Camaro
<A HREF="http://www.1967camaro.net
" TARGET=_blank>http://www.1967camaro.net
</A>
ZZ502 Chevelle
http://www.1970chevelle.net
13 Second Yukon 4x4
<A HREF="http://www.blown4x4.com
" TARGET=_blank>http://www.blown4x4.com
</A>

I did some searching and really coulndn't find anything about rotor phasing. I do remember a discussion about the topic though. If I recall there is really nothing to do with a factory distributor, unless something broke loose or has been messed with.

Anything you can find by "Ignitionman" might be pretty good. Here's a post about altitude and effects on an engine.
http://www.camaros.net/forum/Forum4/HTML/000718.html

Lee,
To correctly phase your rotor with your EFI system, do the following:
1) Synchronize the timing. Make sure that the timing on the laptop is exactly what is measured with a timing light.
2) Turn the crank so that it is about 30 degrees BTDC. Adjust the phaseable cap so that the rotor is lined exactly up with the #1 pole on the cap. Some people will drill a hole in the cap and look at it with a timing light to make sure it is correct to.

Again, make sure your ignition reference angle is AT LEAST 10 more than your peak timing. Change this BEFORE you do the steps above.

If you do these steps you should be good.

Doug