What time do you think my car will run as it is right now?

[CHRIS.O]

Re: What time do you think my car will run as it is right no

Wish I could find the video of my buddies 79 Malibu with a 7.5. It ran low 12's and pulled the front left tire just enough to see light under it. Before the malibu it was in a 84 monte that ran similar times, then after all that it went into my 461 Olds. It is still out there floating around not broken and shattered.

 

[dogsht]

Re: What time do you think my car will run as it is right no

With the 28 spline axles welded tubes and a support cover the 7.5 ain't bad.

Cnuk, Do you have a street car or a drag car? Like current tags & insurance drive it to the track etc. "They" almost always make recommendations for a track car. You might be happier with the result of that $400 going from a rated 2,200 stall to 3,000 that will likely flash at 32/3300 than having something thats a tenth quicker but that you don't like to drive. Food for thought only.

If this is the stock crate 502/502 cam that has a peak HP rating at 5,200 per GM ads & your post and you hit the line at 5,600 as you say.. your about as perfect on your gearing as you can get. Most drag racers find the quickest times going across the stripe about 300 to 400 rpms past peak HP. Not that the motor is done pulling at that point but you ain't going any quicker just spinning your motor harder.

My 509 Cutty ran 110 mph with a 3.42 and 28" drag radial the only time I ever got it to the track.

 

[jimmyp618]

Re: What time do you think my car will run as it is right no

G/N moser axles with a stock 7 5/8 3.42 rear out of a JY s-10 lol

Heres an older vid of a 12.18 on the 7.5. Ill see if i can get one uploaded of one of em under 12.
"http://www.facebook.com/v/1342215030575"

That's impressive and even more so with a 7.5 posi. Is it an Eaton or Auburn posi?.

 

[dogsht]

Re: What time do you think my car will run as it is right no

Junk Yard S-10 would be a factory Eaton with the S clip?

 

[Crazcnuk]

Re: What time do you think my car will run as it is right no

With the 28 spline axles welded tubes and a support cover the 7.5 ain't bad.

Cnuk, Do you have a street car or a drag car? Like current tags & insurance drive it to the track etc. "They" almost always make recommendations for a track car. You might be happier with the result of that $400 going from a rated 2,200 stall to 3,000 that will likely flash at 32/3300 than having something thats a tenth quicker but that you don't like to drive. Food for thought only.

If this is the stock crate 502/502 cam that has a peak HP rating at 5,200 per GM ads & your post and you hit the line at 5,600 as you say.. your about as perfect on your gearing as you can get. Most drag racers find the quickest times going across the stripe about 300 to 400 rpms past peak HP. Not that the motor is done pulling at that point but you ain't going any quicker just spinning your motor harder.

My 509 Cutty ran 110 mph with a 3.42 and 28" drag radial the only time I ever got it to the track.

The Monte is mostly street. The suspension is more roadrace than drag, but it works. From what I understand it will make no difference what stall I use on the street, just have to keep in mind what happens if I put the pedal to the metal! The stall only comes into play if you hammer the throttle.

When I built this car I followed a book that was written by a bracket racer in the 1990's who specialized in 11 second, rear wheel drive, intermediate size cars and after extensive dyno and track testing he found that 3.73 gears work best with a 26" tall tire.

I am only trying to pick up a 1/2 second or so,

 

[dogsht]

Re: What time do you think my car will run as it is right no

I hope you are not getting annoyed with me. That's just it. It will make a difference what stall you use on the street. Ask any converter shop. The difference is if your stall is higher than your cruise rpm than you have constant converter slippage ie megga heat which burns up transmissions. Not on a bracket car but on a street car. Also if your transmission fluid is cooled through your radiator it taxes the rest of your cooling system. It also means she consumes even more fuel your mileage drops and the motor spins more wasted rpm because of the slippage. Food for thought it may not be worth the potential extra tenth.

What book? Are you building a bracket car or an 11 second street car? Peak HP rpm, gearing, tire height, and distance, are math not voodoo. See my last post but try it if you have it as sometimes variables come into play you cannot account for. That said it will most likely just spin your motor harder and go the about the same et. Ok I will stop giving unsolicited help now. I wish you the best and very much respect your car and build. Gbodys are a great platform for a real driven home built hot rod.

Edit Oh hell I lost track of this thread and I am repeating myself. Sorry. BTW 1/2 second is a lot without major changes or a blue bottle.

 

[Crazcnuk]

Re: What time do you think my car will run as it is right no

No, the conversation is interestng. I understand what you are saying, but it is predicated on the fact that my car was already going as fast as it could, which it wasn't.

Basically, it was running 'out of the box' so to speak, and I had no reason to do any more. Now all I am doing is the final tuning that one would usually do.

My freind was 5 time champion in Super comp, and he has been helping me. In between working on mine we tinker on his alcohol roadster.

The converter shouldn't be slipping at cruise speeds as you are not making enough torque to overcome the converter. A lock-up converter would be ideal. I am running an external transmission cooler, filter and thermostatic control valve to deal with any excess heat. As I mentioned, though, I don't plan to change the converter, unless I have to, and I will figure out what I need at that time.

Here is a picture of my launch you can see that, at 14psi, I wasn't getting any 'wrinkle' action happening, but any less pressure and I would tear the tubes. With the lower tire and the rim locks I can drop the pressure, and get the tires to work better to bring down the 60' times which are 1.8-1.9 right now. Tuning the suspension will also help.

As for spinning the motor, 6000rpm was always my finish line target, but as I mentioned I was never supposed to run the 28x10.5 slicks.

 

[dogsht]

Re: What time do you think my car will run as it is right no

I didn't think your current motor etc combo is maxed out. Not that its not running good. It obviously is. I just don't think there is as much left left in the 3500 over a 3,000 for your cam & goals and in the shorter tire as you hope. And that for a driver the last bit might not be worth it.

You may be right the 3,500 may not slip that bad at cruise. My buddies 3,500 stall BBC 462 66 Chevelle did as did my other buddies 3,500 stall Pontiac 467 Judge. Two different converters. Both healthy motors with the chevy having more HP and the Pontiac more torque. I had a 3,000 lock up converter behind my 509 and it was the shitt for a driver. As was the overdrive trans. But I am sure my milder cam more cubes and longer 4.3" stroke brought more torque in sooner. Also you are talking a slick which won't slip on the track and has more tire growth as it spins than the drag radials I am used to working with. Good job on having a separate trans cooler and thermostatic control valve. I didn't assume that. Cheers

 

[pontiacgp]

Re: What time do you think my car will run as it is right no

The converter shouldn't be slipping at cruise speeds as you are not making enough torque to overcome the converter.

torque converters always slip unless your in lock-up mode

 

[Crazcnuk]

Re: What time do you think my car will run as it is right no

The converter shouldn't be slipping at cruise speeds as you are not making enough torque to overcome the converter.

torque converters always slip unless your in lock-up mode

Yes, ALL, meaning no matter what the stall is. I just meant that it won't be slipping any more than usual.