To those of you who run rear leaf springs: Do you notice much difference between a stock-type multi-leaf rear spring vs. an aftermarket mono-leaf or split mono-leaf rear spring?

I see of course that Calvert Racing really promotes their mono-springs.

But what would be the disadvantage of using a stock, multi-leaf spring? Is it less responsive than a mono-leaf? Because the multiple leafs would need to slide over each other?

Would less unsprung weight help somehow?

Yes, I will call Calvert and ask them, but I seek unbiased answers as well. ;^)

Thanks!
T.

I can’t say I noticed a huge performance improvement when I switched from the stock multi-leafs to the Calvert split monos, but I think the theory is that the Caltrac bar can more easily influence and put more arch into a weaker spring.

I’ve been happy with them.

I think the split single leaf is a significant improvement over the stock multi leaf. Reason being, the stock multi leaf has nearly no "give". That was fine for the days when there were basically no traction devices. But if you want to have any degree of adjust ability, the single leaf is the way to go. Your shocks can't influence much, if the spring doesn't give up much in the first place. Take care. Tom Worthington

Best bang for the buck to improve traction and consistency on your truck is to add a weight bar to the back of the bed. About 75 lbs should do the trick.

The split monos are good but not going to make much difference.

The split mono allows for a very stiff front half and light back half. It also allows you to replace the front half when it is bent. I have not personally seen it but I have read where guys are bending the front half of the spring.

You can run muliti spring pack, Take out the over load springs, they are not wanted in a drag truck.

I did not have a positive experience going to the split monos on my car. I fought it for six months before eventually going back to my multileafs. With the multileafs I get alot of separation and comparing it with the split monos, I got very little. I feel like the springs they sent me were too stiff. I believe the spring rate was around 200 were the stock multileafs are around 150. Even with the shocks on full loose, the rear was very stiff. Calvert claim they sent me the correct springs and insisted they were not the problem. I tried everything I could think of with no luck. I would beware if your truck needs alot of suspension separation to work.

quote:

Originally posted by 1leg:
The split mono allows for a very stiff front half and light back half. It also allows you to replace the front half when it is bent. I have not personally seen it but I have read where guys are bending the front half of the spring.

You can run muliti spring pack, Take out the over load springs, they are not wanted in a drag truck.

That’s interesting to read. I’m getting close to 20 years since switching to the split mono. I’m still running the original front halves, but I’m on my 3rd set of rear halves.

quote:

Originally posted by Brktracer:
Best bang for the buck to improve traction and consistency on your truck is to add a weight bar to the back of the bed. About 75 lbs should do the trick.

The split monos are good but not going to make much difference.

Or you could pt the battery in the back.........

quote:

Originally posted by Curly1:

quote:

Originally posted by Brktracer:
Best bang for the buck to improve traction and consistency on your truck is to add a weight bar to the back of the bed. About 75 lbs should do the trick.

The split monos are good but not going to make much difference.

Or you could pt the battery in the back.........

Both. I don’t have a truck, but my trunk area contains 2 batteries, the fuel cell, and about 200 lbs of lead.

I just copied my response from the other thread as I think it applies same here.

If it was my car I would not use the sliders or spend much money on the stock type suspension.

I would run it as it is as long as possible and then when it comes time where you have to do something then go with good 4 link or ladder bar type suspension and coil overs.

I just do not see spending much money on it when eventually you are still going to have to change out rear suspension IMHO.

I have a friend he has plenty of money and asked a bunch of racers what to do with his racecar. Everyone of us told him to back half it with big tires. So he decides he is going with small tire and Caltracks and Caltrack springs. His tires do not last long and if track is not just perfect he can not get down the track. Now he is going to back half his car so he wasted all that time and money trying to work with stock type suspension. He probably spent almost as much money on the stock type suspension and still going to have to change. Now if you are racing stock class and required to run it then that is different but other than that I would just wait and back half it. My opinion.

quote:

Originally posted by Bad Nusz:
To those of you who run rear leaf springs: Do you notice much difference between a stock-type multi-leaf rear spring vs. an aftermarket mono-leaf or split mono-leaf rear spring?

I see of course that Calvert Racing really promotes their mono-springs.

But what would be the disadvantage of using a stock, multi-leaf spring? Is it less responsive than a mono-leaf? Because the multiple leafs would need to slide over each other?

Would less unsprung weight help somehow?

Yes, I will call Calvert and ask them, but I seek unbiased answers as well. ;^)

Thanks!
T.

Travis or John will guide you.. On a .05 tree ? If it helps.... Huge difference on my Camaro. Average before 1.45-1.50 rear wheel 60 vs 1.35-45. When I limited the wheelies it went 1.30-1.32. I had multi leaf and Calvert before. We now have Calvert mono leaf designed for the car. You will need weight bias/scales at some point to know where you are and going. My car has 7.5 front end travel and 54% front end. Are you flashing your converter or really pushing it? I flash mine from 2800-3200 with a 6100 stall. With my car race ready I run .050 between the roller and spring with me in the seat. Probably close to most stocker setups.

[/QUOTE]

That’s interesting to read. I’m getting close to 20 years since switching to the split mono. I’m still running the original front halves, but I’m on my 3rd set of rear halves.[/QUOTE]

You maybe right, its possible I have that backwords, but the info I was getting was from guys running about 1800+ HP with buggy springs and small tires.

quote:

Originally posted by banjo:
I did not have a positive experience going to the split monos on my car. I fought it for six months before eventually going back to my multileafs. With the multileafs I get alot of separation and comparing it with the split monos, I got very little. I feel like the springs they sent me were too stiff. I believe the spring rate was around 200 were the stock multileafs are around 150. Even with the shocks on full loose, the rear was very stiff. Calvert claim they sent me the correct springs and insisted they were not the problem. I tried everything I could think of with no luck. I would beware if your truck needs alot of suspension separation to work.

Banjo, I witnessed a very established racer having the same problems you were at the Team Finals last year. I spoke with him in the staging lanes to see why his car ran off & he explained he put split mono leafs on it. He swapped his multileafs back in that night and the next day his problem was solved. I’m not knocking splits because there are plenty of people using them with great results.

quote:

Originally posted by Curly1:
I just copied my response from the other thread as I think it applies same here.

If it was my car I would not use the sliders or spend much money on the stock type suspension.

I would run it as it is as long as possible and then when it comes time where you have to do something then go with good 4 link or ladder bar type suspension and coil overs.

I just do not see spending much money on it when eventually you are still going to have to change out rear suspension IMHO.

I have a friend he has plenty of money and asked a bunch of racers what to do with his racecar. Everyone of us told him to back half it with big tires. So he decides he is going with small tire and Caltracks and Caltrack springs. His tires do not last long and if track is not just perfect he can not get down the track. Now he is going to back half his car so he wasted all that time and money trying to work with stock type suspension. He probably spent almost as much money on the stock type suspension and still going to have to change. Now if you are racing stock class and required to run it then that is different but other than that I would just wait and back half it. My opinion.

Curly, what kind of vehicle & how fast was your friend running with the Caltracs? I’m only running in the 6.70 area, 1/8 mile, and have the exact opposite results as he was. I usually change my slicks after 300 runs or so because I feel guilty & when the track is not perfect I feel like I have an advantage. I think I read somewhere that the OP is a high 11 quarter mile truck, IMO a back 1/2 is a waste of time & money.

quote:

Originally posted by the rain maker:

quote:

Originally posted by banjo:
I did not have a positive experience going to the split monos on my car. I fought it for six months before eventually going back to my multileafs. With the multileafs I get alot of separation and comparing it with the split monos, I got very little. I feel like the springs they sent me were too stiff. I believe the spring rate was around 200 were the stock multileafs are around 150. Even with the shocks on full loose, the rear was very stiff. Calvert claim they sent me the correct springs and insisted they were not the problem. I tried everything I could think of with no luck. I would beware if your truck needs alot of suspension separation to work.

Banjo, I witnessed a very established racer having the same problems you were at the Team Finals last year. I spoke with him in the staging lanes to see why his car ran off & he explained he put split mono leafs on it. He swapped his multileafs back in that night and the next day his problem was solved. I’m not knocking splits because there are plenty of people using them with great results.

Agreed, not knocking them, but I could not get them to work with my car. I just think they gave me too stiff of a spring rate.

Rainmaker, My friend is running a 56 Chevy with a 9 x 28 tire and he said his car weighs like 3400? his best pass is 6.3X He bought the Caltrack, the leaf springs and the shocks. I think he said he is getting around 50 passes before sidewalls go away and his reaction times go away. His car looks good and works pretty good but he is working the tire hard. Your mileage may vary. I think if he could run a bigger tire, if his car was not as heavy or as fast the tires would last longer.
In any case he is now talking about back halfing it and going to a 14 x 32 tire. Which is what we all told him he will want to go faster and then he will wish he had back halfed it in the first place.

For you if you are getting 300 runs and the reaction times are not going away and car still hooks up good I would keep on doing what you are doing. Note, sometimes the reaction times start going away but the tire is still hooking good. If you are like most of us and always want to go faster then........

Also I like a larger tire for those times when track get hot and greasy or just not in top condition gives you a little more room for error. Once again if your stuff is working like you want then no reason to change. For the OP I think he is having issues and trying to resolve them. So my advice to him instead of keep putting Bandaids on a problem try to resolve it (If he can afford it)

Love the Calvert split mono's and bars. I have thousands of passes on the Firebirds setup and they have been on there about 20 yrs !! Same set !! Car weighs 3300lbs and has been 9.50's @ 142mph on a 10" tire , 1.35 60' I used the 1" drop springs, not sure of the rate. Never replaced front or rear halves

I like them so much I just build my new truck around them but using a big tire and an anti roll bar. Truck leaves and drives like a Cadillac, I am very pleased with it !!!

I have used and seen Caltracs with factory mono leafs and multi leaf on a few cars and they still seem to work well, but most of those cars were a bit slower.

I have not used rear slider yet and I don't feel the rear shackle is a limiting factor. Good bushings and solid shackles and no problems. I will be using sliders on a 69 Camaro I am building because it will simply be easier to fabricate the rear spring mount as a slider because there's nothing there for a typical shackle and I want to use leaf springs. We'll see how that goes .......

Anything to help a truck hook is money well spent in my opinion.

This message has been edited. Last edited by: HS professor,

quote:

I just copied my response from the other thread as I think it applies same here.

If it was my car I would not use the sliders or spend much money on the stock type suspension.

I would run it as it is as long as possible and then when it comes time where you have to do something then go with good 4 link or ladder bar type suspension and coil overs.

I just do not see spending much money on it when eventually you are still going to have to change out rear suspension IMHO.

I have a friend he has plenty of money and asked a bunch of racers what to do with his racecar. Everyone of us told him to back half it with big tires. So he decides he is going with small tire and Caltracks and Caltrack springs. His tires do not last long and if track is not just perfect he can not get down the track. Now he is going to back half his car so he wasted all that time and money trying to work with stock type suspension. He probably spent almost as much money on the stock type suspension and still going to have to change. Now if you are racing stock class and required to run it then that is different but other than that I would just wait and back half it. My opinion.

How fast is your friends car ???

That goes against my person experience. We get about 250 runs out of M/T 29.5x10.5 PBR's on the firebird and take them off and use them on slower cars. Tires literally need no smoke from a burnout. And we have about 125 runs on Hoosier 29.5x11.5W's on the truck, they are big. They are bias and Do6 compound I think. Not sure how far we can go with these but so far reaction time and consistency is still solid.

He is trying the Radials and maybe they will last better. His car runs 6.3x-6.40x in the 1/8.