Ok, I know I should put it on a dyno to get the real answer.

But maybe some of you have the experience I to tell me sth.
I think my zz502 could be a bit stronger then it is at the moment.

When it´s warmer outside and I let it roll in 1st gear at low speed, and then stomp on it, rear wheels spin and rpm rises crazy.
I have a M21 close ration with a very long 1st gear, rear is 3,7.
So i can pull 1st gear around 45mph. Well because of spinning I shift earlyer. In 2nd gear, wheels are close to spin, but they don´t really do it, speed is then around 60mph. (Tyres are BFG 225mm)
I get them to spin in 2nd only on smooth roads and race tracks which are usually very smooth.

Y this engine gets lazy when it hits 5000rpm. Says everybody, but this is not so important for me, I like the lower rpm and torque settings.

When it´s cold outside, around 15°C the engine feels Feels like 10% more power, and throttle response is awesome.

Maybe I am expecting too much, or I have adapted to the power.

This 502 has of course a lot more power than my 454 LS5 had. Would say feels like 150hp more, and at least 100 more then a L68 (400 SAE HP but old and not restored) from a friend.

So I would be interesed until which speed you can spin the wheels on a sticky road, without spoiling the wheel spin with the clutch, just using the torque of the engine.

 

a well tuned 502 should boil the tires and the car should only go about 10 ft by the time you shift to third if its running correctly

in my experience

your question is not about traction so something is wrong

 

Well I can do this if I want to, from a standing start.
But the question was not about burning rubber. You can do this even with a normal small block.

The main question is, until which speed should there be wheelspin during acceleration. So you can not fully press the pedal.

 

WAY to many variables to answer that question. Road condition, surface (asphalt, concrete, etc.), tire compound, humidity, surface temperature, air pressure, throttle control, on and on and on...

 

it should run 1-8-4-3-6-5-7-2

 

like a raped ape?

 

Twice as good as a 251?

Scott

 

More of what Ibenaz540 said. There is even different mixes of blacktop mix from region to region. Even concrete has different "rakes" or broom surfaces...this makes a huge difference in how your car will hook up. I wouldn't give this or "tire spin" much creedance.

Maybe you could find a vacant strip of road, start taking some notes in a notebook on temp,air density, performance on the SAME road and see what you come up with after tuning or chassis-tire changes.

Good luck!

 

After seeing some of your acceleration runs on the racetrack videos I'm surprised to see you post this thread. Your car sure looked impressive and certainly left everyone behind coming out of a corner at one point.

Have you checked your timing and taken a vacuum reading? Do you have any problems or just a feeling that the car should be faster?

If you are not running the rpm up high, I'd consider getting some wider/stickier rubber under the car, so you can utilize the engine's power down low to the maximum extent. That way you would be extending the engine's useful operating range.

And you do get used to the power after a while and what impressed you on the first ride may not seem all that crazy in time. Do you have access to a dyno? That's going to tell you where you are. Do you still have 1 Max-Flow and the other side equipped with a lesser flowing insert?

 

I think thats the problem (maybe). Sometimes I think "this engine is rated at 500hp - shouldn´t it feel like more?"

Some weeks ago I beated a new Porsche Boxster S from a stoplight.
The Porsche is rated 5,1s from 0-60mph. So my Vette should be a bit faster.

As I wrote in my first sentence, I have to put it on a dyno.

 

I've driven a few ZZ502's and I may get flamed for this...but I was way less than impressed. Now that's not because my 555 makes 870+HP...it's because it just didn't seem to run like the sum of the parts indicated. I sold a buddy my old '68 SS/RS Camaro and he wanted to save $$ and not take my old 427. He went through a couple of mild 454's and finally installed a ZZ502. All I can say is the old 427 would have spanked it all day long even though it had about 10.0 compression, pocket ported iron GM oval ports with stock 2.06 valves and a relatively mild solid flat tappet cam. The car had 3.73's in it at the time with a 3600 stall converter. The ZZ502 would come up to RPM quickly but after 5000 it was like you said..out of steam. That's just not enough RPM to work with.

The best thing I've ever seen for one is a cam change. The rest of the parts are fine.


JIM

 

I had one in my 72 for a while..........it would roast the tires for sure , it seemed to lack the low end stump pulling torque I thought it should have too. as far as hitting second gear........one of the very few times I ran it really hard , i hit 2nd and did a quick 540 spin. some of that could be chalked up to driver inexperience but most was just lighting up the rear tires at about 35-40 mph

 

Zuendler
is your engine properly tuned? i mean advance and carb jetting

searching the net i found this report about zz502 :

Car Craft ran a dyno test story on a ZZ502/502 crate engine back in their May '99 issue. I was just looking at this issue a few days ago. Here is what they found on the dyno, including some jetting changes they did which might help you out:

GM Crate Engine ZZ502/502:

Dyno testing was done through 1 7/8" headers exiting through 5" truck mufflers rated at 400 HP apiece.
Carb was the GM supplied 850 Holley
HEI distributer
Actual compression ratio of this engine is 9.2:1 - GM says it's 9.6:1
Engine was found to not be knock-sensitive on 92 octane pump gas no matter how much total timing was used during testing.
With the stock 850 Holley atop the GM dual plane intake using the GM-recommended 36° total timing, the 502 made 582.7 lb/ft @ 4000 RPM and 518.6 HP @ 5500 RPM. They noted the stock jetting was lean, so they bumped up the jetting from the stock #78 primary #82 secondary to #84 primary and # 86 secondary which produced the best power of all the runs at 586.3 lb/ft and 528.1 HP.