Steel VS Cromoly rollbar?
#1
Steel VS Cromoly rollbar?
I picked up a used Wolfe 6pt rollbar at a good price this winter.
I have not installed it yet, I'm starting to wonder if maybe Cromoly would have been a wiser choice.
So $685 for a new rollbar (weld-in, jig notched, over the seat + shipping)
Looks like a difference of 45lbs (85 VS 130)
45lbs is significant; but then again, my car is a pig anyhow.
I could probably get $200 out of the old bar if I sold it.
Thoughts?
I have not installed it yet, I'm starting to wonder if maybe Cromoly would have been a wiser choice.
So $685 for a new rollbar (weld-in, jig notched, over the seat + shipping)
Looks like a difference of 45lbs (85 VS 130)
45lbs is significant; but then again, my car is a pig anyhow.
I could probably get $200 out of the old bar if I sold it.
Thoughts?
#2
I don't hear of ANYONE using mild steel, almost everything is Chromoly since its adds so much weight to begin with, most people who race want that penalty to be as low as possible.
#3
A lot of people use mild steel. I don't because I'm concerned about weight, and tig welding looks so much nicer. Some don't think it is worth the cost difference, some do. A lot of cars come through here with mild steel roll bars.
#4
I don't think there is that much weight difference in a 6pt bar set-up unless the MS tube wall was overly thick.
Bird in hand, its there use it.
I went to school for physics and honestly MS is the better material to use in pretty much anything over 2700lbs. There is a reason why every major sanctioning body that deals with door-style cars do not allow chromoly to be used in the rollcage portion of the cars. Chromoly is brittle compared to MS and when you weld chromoly it becomes even more brittle. Chromoly is very difficult to weld correctly as well.
If you ever get to inspect a bad accident involving a chromoly car you will see lots of broken tubing generally before or after the welds, whereas if you look at a nascar wreck all you see is bent tubing.
Bird in hand, its there use it.
I went to school for physics and honestly MS is the better material to use in pretty much anything over 2700lbs. There is a reason why every major sanctioning body that deals with door-style cars do not allow chromoly to be used in the rollcage portion of the cars. Chromoly is brittle compared to MS and when you weld chromoly it becomes even more brittle. Chromoly is very difficult to weld correctly as well.
If you ever get to inspect a bad accident involving a chromoly car you will see lots of broken tubing generally before or after the welds, whereas if you look at a nascar wreck all you see is bent tubing.
#7
I think your mistaken. NHRA does allow cm for roll cages. My SS car is certified to go 8.50, most of my friends have full cages and are certified to 7.50, those are also NHRA Super Stock and Comp Eliminator cars. Pro Stockers are cm also, but only have to weigh about 2350. All full cm tubing. Tig welded and anealed properly, there are no problems.
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#8
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I think your mistaken. NHRA does allow cm for roll cages. My SS car is certified to go 8.50, most of my friends have full cages and are certified to 7.50, those are also NHRA Super Stock and Comp Eliminator cars. Pro Stockers are cm also, but only have to weigh about 2350. All full cm tubing. Tig welded and anealed properly, there are no problems.
#9
i just bit the bullet and installed a 10pt chromoly. Yes it cost a few hundred more, and yes my car was already a pig..almost 3900 lbs. I figured i should cut weight where i could and not regret it later. IMO buy a choromoly.
45lbs seems like a lot, maybe a 10pt? 6pt difference i dont think is that much?
45lbs seems like a lot, maybe a 10pt? 6pt difference i dont think is that much?
#11
Ed I meant to type other than NHRA/IHRA drag racing.
SFI Foundation gets their chromoly destructive testing info from the airplane industry thats directly related to drag racing right??
Chromoly does have its place in the drag racing world and I'm sure nothing I say or type will change that however I've done the math and seen the results first hand on the heavier stuff and the lost the life of a good guy/friend (Ian Landies Sr.) with improperly welded CM by a supposid professional chassis shop.
James Montigny, why can't you add swing outs to your mildsteel bar? Plenty of bars have been retro-fitted with swingouts
SFI Foundation gets their chromoly destructive testing info from the airplane industry thats directly related to drag racing right??
Chromoly does have its place in the drag racing world and I'm sure nothing I say or type will change that however I've done the math and seen the results first hand on the heavier stuff and the lost the life of a good guy/friend (Ian Landies Sr.) with improperly welded CM by a supposid professional chassis shop.
James Montigny, why can't you add swing outs to your mildsteel bar? Plenty of bars have been retro-fitted with swingouts
#12
I just had a Wolfe CM 6 point installed and it weighed in at under 65lbs out of the car. I got the Wolfe swingouts but I would advise against that, they are very intrusive at the pivot, look like crap, and use small pins. My fabricator later told me he uses Chris Alston swingouts and I would have much rather had them. If I were you I would try to find a semi local shop with a good rep to do a custom install. It will fit alot better and probably won't cost much more, if any at all.
Larry
Larry
#13
I just got a wolfe 6point notched cromoly and the shipping "bundle" is 57.77#s
I have a wolfe bolt in MS. thats I'll weight if I get a chance. But just a box I put all the 3/8th plate bolts/washers/nuts,(24 of them) and the 4 big 1/2 bar hardware, and the under floor 1/8 6x6 plates. That box is like 12-15#s right there.
I have a wolfe bolt in MS. thats I'll weight if I get a chance. But just a box I put all the 3/8th plate bolts/washers/nuts,(24 of them) and the 4 big 1/2 bar hardware, and the under floor 1/8 6x6 plates. That box is like 12-15#s right there.
#16
I have nothing to confirm or argue those numbers.
I shouldn't need a 10pt anytime soon. I'm looking at low 11s N/A
Although, you never know what the next season will bring
I just had a Wolfe CM 6 point installed and it weighed in at under 65lbs out of the car. I got the Wolfe swingouts but I would advise against that, they are very intrusive at the pivot, look like crap, and use small pins. My fabricator later told me he uses Chris Alston swingouts and I would have much rather had them. If I were you I would try to find a semi local shop with a good rep to do a custom install. It will fit alot better and probably won't cost much more, if any at all.
Larry
Larry
I talked to the gentleman who sold me the rollbar (and who would be installing it) today and
he said he could fab me up a CM rollbar, so that makes the decision much easier.
I'll have to prod him for a price and timeline when I get the car back from being tuned this month.
Or rather that it would be difficult to remove, yes.
#17
I would go molly, if you sell the car or ever want to upgrade you can allways add on with the molly but past a 10 point I don't know anyone that would add on a 25.X to a 10 point, they pretty much allways want to cut them out and start over.
My notched molly WOLFE 10 point for my last car had a shipping weight of like 72 pounds and I really think the mounting plates weighed a good 20 pounds
#18
At that point, I'd just buy a rolling chassis I didn't have any emotional
attachment to and start hacking away at it.
#20
ill be puttin in a 10pt soon and we'll probably be goin with a MS cage just because the money but id love to save the weight with CM. ill probably be usin a chris alston kit that doesnt go through the dash. if i could afford it id use the CM so if you have the money do it.