[nabit]

Ok this is after going from 2 flats to 4 flats and having 10lbs in the 12.5x28 m/t E.T. street drag tires with tubes on 15x10 rims. I flashed it from a little off idle and got a 1.62 60ft but I broke loose at half track. Let me know what you see in the launch and what I can do to make it better. It is a 496bbc with 4.30 9" and spool with caltracs and new multi leaf springs with rancho 9 ways on back set on 2 and 90/10 drag shocks with moroso trick springs up front and it also has subframe connectors, rest of suspension is stock. I list this so that it might be easier to tell me if you have all the info again.

I am planning next time to add 2 more flats and go up in pressure around 12-13lbs.
http://www.youtube.com/watch?v=KX8lfyLBExY

 

[tbills66]

Looks like it is seperating the rear too quickly. Looks like you might need to move the bar to another position and slow the rebound on the rear shocks. It also looks like the air pressure is too low and walking on the back tires. It's kind of hard to tell the tires from the video.

 

[bowtie0069]

I would add about 3 or 4 psi to the tires. Where is the pinion angle? Mine won't hook with less than 4° down; and I run the full 8 flats and use the top hole. I have QA-1's on full soft, but I know Calvert likes his car hard as a rock. With 100 lbs. in the trunk mine will stand on the bumper. How much travel do you have up front--it didn't look like it rose much before it fell back down. Got the snubbers trimmed? Everything nice and loose in front?

 

[71SS454]

It dosen't look like you're getting much body seperation at all in the rear. Are you using the top hole or the bottom hole? Also, I'd try stiffining up the rear shocks to try to keep it from unloading in second gear, also agree more tire pressure. JMO.

 

[NOVACA1N]

Problem is in the front..

 

[nabit]

I am running 4.5degrees down for pinion angle. I am in the top hole with 4 flats. I am running the rancho 9 way shocks on the 2nd setting which is 2nd to softest. I have 5.25 front travel on stock suspension with moroso trick springs and 3 way adjustable shocks on 90/10. No sway bar and the snubbers are cut down some already. Stock rubber bushings every were.

I noticed that the body seperates some and then the tires start to spin what will correct that, more flats?

Suggestions so far are: go to 6 flats, 13lbs in tires, softest setting for rear shocks.

Novacain you mentioned the problem is up front, what do you see that can help that?

 

[NOVACA1N]

Steel head or aluminum head on the 496?

IMHO..

The rear shocks are currently on 2, and the thing is already porpoising pretty badly...Why would you want to go softer on the shock? I would tighten it if anything, to keep the tire planted. When I start to tune out a new combo, I start in the middle or at least close to it and work either way. Not sure why you're running so much preload in the top hole..Your nose heavy car might like the lower hole better anyway. There is no way you have over 5" travel with how high your car sits in the front..Did you measure correctly? Upper control arm snubbers should be removed completely, not just cut down. And the million dollar question..

I noticed that the body seperates some and then the tires start to spin what will correct that, more flats?

Pitch rotation! Unfortunately, with stock rubber bushings up front and an improperly setup rear suspension, this will not happen. You have a nose heavy car with a small tire...The idea is to get the car up on the tire quickly and efficiently. The stock stuff binds pretty badly, and if those Moroso springs are more then 6 months old they're probably junk already.

I'm not excited about your front shock selection, but they will work for you and at this point in time a better shock won't do much of anything for you. I advise replacing your front bushings with some sore of bind-free bushing i.e. AFCO/Global West, just stay away from polyurethane JUNK!

In conclusion..
-Better bushings
-Lower front/more travel
-Tighter rear shock
-Play with top/bottom hole, I advise the stop bar just touching the spring with driver weight in the car

It drives me nuts when I see people misinforming others on message forums. People spend countless hours/dollars on their rear suspension chasing traction issues, when the problem is usually in the front. The car very well MAY work on a good track...But an efficient 60 foot is something you will NOT have, and on a marginal track on a hot summer day, you are dead!

Joe

 

[nabit]

Thanks Joe I appreciate it!!

It is a iron head 496.
I have the shocks on 2 because that is what the caltrac guy told me to start at when I first run the car. I never changed it because I have had so many mechanical issue with the tanny and stuff that I never even had a change to tune the suspension yet.

The front has been like that for a few years and was all put together on a budget. The bushings and springs were already there when I bought it. I want to step up in the near future but I have to due it piece by piece.

I appreciate the info and I will try some of it out for sure and piece together the rest.
thanks,
nathan

 

[levisnteeshirt]

hmm

very nasty sounding car :devil:

I think i would try less gear with that beast, at least at this point working with drag radials. I'd let the torque of that bruiser 496 and converter do the work. I think i'd look at a set of sliders to help the car hook up.

After watching the video at least 10 times , I'm wondering if it has a cage in it and if its tied to the frame connectors or front and rear subframe ??? If it isn't i would. Looks like you have one helluva engine and now the effort will go forward working on the suspension and frame.

 

[NOVACA1N]

very nasty sounding car :devil:

I think i would try less gear with that beast, at least at this point working with drag radials. I'd let the torque of that bruiser 496 and converter do the work. I think i'd look at a set of sliders to help the car hook up.

Sliders are a waste of money and will NOT help his problem. Less gear won't help either..:no:

 

[levisnteeshirt]

Sliders are a waste of money and will NOT help his problem. Less gear won't help either..:no:

So your saying this car is having a hard time with traction , it has a 496 that prolly makes a ton of bottom end torque , 4.30 gear with a 28 inch tire ,, So your saying it needs more gear ??? Is the inverse true in this situation ??

I'd limit the front end travel myself , but i know how some of you wizards on here think a drag car is suppose to look like a monster truck going down the track.

Limit the front wheel travel , then the Caltracs will exert more downward force to increase the traction because now they're working against the full weight of the car and not getting asistance from the front springs to transfer weight, then he could add some air to the tires because now the suspension will now be working harder , and sliders will help create this situation even more by freeing up the rear axle to apply more torque to the chassis, it will be 10 times easier to drive because the energy in the body will be under control

 

[NOVACA1N]

So your saying this car is having a hard time with traction , it has a 496 that prolly makes a ton of bottom end torque , 4.30 gear with a 28 inch tire ,, So your saying it needs more gear ??? Is the inverse true in this situation ??

I'd limit the front end travel myself , but i know how some of you wizards on here think a drag car is suppose to look like a monster truck going down the track.

Limit the front wheel travel , then the Caltracs will exert more downward force to increase the traction because now they're working against the full weight of the car and not getting asistance from the front springs to transfer weight, then he could add some air to the tires because now the suspension will now be working harder , and sliders will help create this situation even more by freeing up the rear axle to apply more torque to the chassis, it will be 10 times easier to drive because the energy in the body will be under control

I'd leave the gear alone. So let me get this straight...You want to limit the front end travel in a car that does NOT hook? That will only make his problems worse. Your theory on how to properly and efficiently launch a small tire nose heavy car is very wrong. You need to get the car up on the tire i.e. pitch rotation therefore front end travel and its ability to be a full extension quickly is crucial, until you get to the point where it starts to wheelie too hard which will not happen with the car in question.

But what do I know about getting a car to hook..

My 3400lb+ car only 60 foots 1.33 leaving at 1600 off the footbrake. My car does NOT have sliders, and has almost 6" front end travel. I am on a radial too...I'm willing to bet my 93 octane burning naturally aspirated small block makes more torque than his big block.

Here's only a small portion of my resume guy...Where's yours? I'm no "wizard", but I am doing far more with much less compared to the majority of the racing community..

 

[nabit]

Hey thanks guys for all the help and advice..I didn't mean to start any fights...

Joe I went back and looked at my book that has my measurements in it and I am actually at 4 7/8 of front in travel measured with the car on the ground by a reference point and then using the same point and raising the car until the tires are off the ground.

I will try setting the shocks harder first and see were I go along with adding more tire pressure to see what happens.

I did try the bottom hole and went from no preload to 4 flats and all I did was spin so i went to the top hole and every flat of preload I add causes the car to spin less and less.

I went from spinning past the 60ft in the bottom to were it is now.

Oh and I am not on drag radials I am on bias et street 28x12.5.

As far as power I am in the 650+hp range and 625+tq range based on other engines dynod like me but I have more cam, heads, compression and different intake then they had...I know no engine is the same and I can't compare them completly but that is as close as I can get..

When I get some funds in I will go to different bushings. Can the sluminum ones you use last on the street or do they wear out fast?

 

[Eddie Wilson]

front end travel

Looks to me that the front is very limited in travel. also a possiblity of too much preload in the Caltracs.. Also with the bigblock, the weight bias prob is not idea, So getting the weight to transfer is a must.
I'm just throwing out a few ideas.

The aluminum bushings I used to have with the caltracs had a steel sleeve, so they would not wear out.

 

[nabit]

Looks to me that the front is very limited in travel. also a possiblity of too much preload in the Caltracs.. Also with the bigblock, the weight bias prob is not idea, So getting the weight to transfer is a must.
I'm just throwing out a few ideas.

The aluminum bushings I used to have with the caltracs had a steel sleeve, so they would not wear out.

Sorry I didn't state that well, I was talking about the front bushings.

If I go with less preload I spin but then that could be do to the rear shocks being so soft. I will try them at 5 out of 9 instead of 2 and see if that helps.

I appreciate all the info everyone, thanks!!

 

[Eddie Wilson]

Sorry I didn't state that well, I was talking about the front bushings.

If I go with less preload I spin but then that could be do to the rear shocks being so soft. I will try them at 5 out of 9 instead of 2 and see if that helps.

I appreciate all the info everyone, thanks!!

If my memory serves me correct. When I ran the Rancho/ Caltrac set up. I had the rear shocks set the softest in compression and hardest to seperate. This aided in helping the car rotate yet not let the rear seperate and bottom out the shocks. There is alot of tricks you can do the the front A arms to free them up.
Good luck!
EWW

 

[nabit]

If my memory serves me correct. When I ran the Rancho/ Caltrac set up. I had the rear shocks set the softest in compression and hardest to seperate. This aided in helping the car rotate yet not let the rear seperate and bottom out the shocks. There is alot of tricks you can do the the front A arms to free them up.
Good luck!
EWW

My ranchos 9000 only have 1 adjustment but 9 settings? your ranchos were double adjustable? what kind are they?

 

[Eddie Wilson]

My ranchos 9000 only have 1 adjustment but 9 settings? your ranchos were double adjustable? what kind are they?

Sorry, I had the 9000 shocks like you. The adjustment is for compression? correct? Its been years since i fooled with leafs.

 

[tbills66]

One way I was told to check the front springs was that you should be able to lift the front end of the car to the stops manually, with no jack and it doesn't take an extreme amount of effort. I was also told that those springs are replaced at least once a season.

novacain sounds and looks like he knows what he is talking about. Proof of performance is always a good thing.

 

[nabit]

What are good springs Joe? I didn't see anything mentioned about a brand for those only the bushings.
thanks!!