Author Topic: Modifying a chassis to meet spec  (Read 14984 times)

Offline andrewb

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Modifying a chassis to meet spec
« on: March 06, 2014, 09:46:52 AM »
I have a couple of questions regarding chassis modifications in order for it to meet the SFI 2.6A Spec, which I own a copy of (should be free if you ask me). I need to remove or replace several of the back half uprights as well as the expanded metal “seat”, that’s welded to the frame. I didn't find anywhere in the spec about grinding on the frame rails. I only plan on removing the welds but, you know, things happen and I could unintentionally hit the rails.

Unless it’s completely obvious, do they even ask or look for such things when inspected a car? Anyone here have any tips or advice getting this hot rod up to date?

Thanks,

Andrew

Offline janjon

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Re: Modifying a chassis to meet spec
« Reply #1 on: March 06, 2014, 10:25:26 AM »
You might want to survey the entire back half for wall thickness. that chassis looks to have been around long enough for possible corrosion from the inside... Do you have access to an ultrasonic thickness checker?
John
Just keep the same amount of stuff on the right
as there is on the left. Seeing straight ahead is highly overrated....

Offline andrewb

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Re: Modifying a chassis to meet spec
« Reply #2 on: March 06, 2014, 10:31:01 AM »
Ya, I planned on checking it out closer once I get it home. I know of someone with a ultrasonic thickness gauge, we used it in the past to check cylinder walls.

Andrew

Offline janjon

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Re: Modifying a chassis to meet spec
« Reply #3 on: March 06, 2014, 05:22:03 PM »
I haven't had a chassis certed, but it's my understanding the inspection will be pretty thorough .(And pretty expensive. $400.00 I think?) At the very least, if you find sub-wall thicknesses, your car doesn't look like it would be that hard to back-half partially or entirely. It's not a good feeling to realize you bought a car that won't pass, and there are umpteen flippin' uprights that would have to be cut loose from a shoulder hoop that checks .002 too thin, EVERY other piece of tubing checking to spec. Ask me how I know...
 Said shoulder hoop has a couple of grinding nicks from when I cut off the old cage, and has some small holes I suspect are snap-attachment upholstery way back when; I also suspect the existence of those holes permitted some (slight?) corrosion from the inside. My intent is tig them up and smooth them off for appearance. I forget where it prohibits grinding of structural welds, whether it's SFI or NHRA, but I don't see filling and filing a nick otherwise as a no-no.
 One thing's for sure, there are a good several knowledgeable and experienced chassis building pros and others on this site who will give guidance, tips and tricks of their trade to us folks who want to do this ourselves. Ask me how I know...
 Anyway, Welcome, Andrew. You'll find this site to be a gold mine.
John Williams
 
Just keep the same amount of stuff on the right
as there is on the left. Seeing straight ahead is highly overrated....

Offline masracingtd1167

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Re: Modifying a chassis to meet spec
« Reply #4 on: March 08, 2014, 10:46:25 AM »
I think my last re cert was 150.00 . As far as the chassis passing they only check the driver area . The only problem you might have is the tubing thickness . A lot of the old cars were made out of .049 and the newer cars are .058 

Offline janjon

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Re: Modifying a chassis to meet spec
« Reply #5 on: March 08, 2014, 11:39:19 AM »
I stand corrected, evidently, on the cert cost, see some recent references to $150, that's better than I thought...
 
Just keep the same amount of stuff on the right
as there is on the left. Seeing straight ahead is highly overrated....

Offline denverflatheader

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Re: Modifying a chassis to meet spec
« Reply #6 on: March 08, 2014, 04:09:27 PM »
janjon – actually depending on your situation, the chassis cert could cost more than $150.  A comparable chassis cert for TAD would be $750, not sure but top fuel is probably more.  Plus the nhra sfi tech can charge you mileage when he/she has to drive to your location.  Imagine if the closest tech was 400 miles away from you…   add the charge per mile to your/my $150.  Most tracks have a sfi tech day, one way to bypass the mileage charge.  DF

Offline janjon

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Re: Modifying a chassis to meet spec
« Reply #7 on: March 08, 2014, 05:20:14 PM »
My Div. director was in Conroe, TX last I checked, about 45 min away, so me dragging the carcass to him would be the way to go. My chassis won't cert anyway without the shoulder hoop replacement, which I'm not gonna do now anyway. Probably never, I could build an entirely new chassis for the same or less work with a better result.
Just keep the same amount of stuff on the right
as there is on the left. Seeing straight ahead is highly overrated....

Offline rooman

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Re: Modifying a chassis to meet spec
« Reply #8 on: March 11, 2014, 07:13:53 AM »
Andrew,
             you may find that it will be easier and cheaper to build a new frame rather than trying to update that one. As mentioned most of the older cars are "O too thin" and looking at your photo I see that a lot of tubes will probably need to be upsized. Another thing is that the motor appears to be way back in the car and if you have to move it forward to get a transmission to fit that will open a whole new can of worms. Several chassis builders have kits available as well as blueprints and bends.

Roo
Yeah, I am from the south--any further south and I would have been a bloody penguin.

dreracecar

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Re: Modifying a chassis to meet spec
« Reply #9 on: March 11, 2014, 09:04:50 AM »
What you have there is the beginnings of a cacklecar which does have good value "as is" to those that go that direction. Its not worth trying to update it if one has to replace 50% or more of the tubing and add more to whats left which happens to be really old tubing.
   Frames are the easiest parts to build, its all the other crap that goes on them that takes time and money to do and since you have to do that anyway, just start off with a new frame and sell that one for someone to restore

Offline andrewb

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Re: Modifying a chassis to meet spec
« Reply #10 on: March 11, 2014, 10:59:18 AM »
Maybe I'll put it on ebay, less the wheels, front axle, and steering box to see what I can get. I can't really afford to have a chassis made right now but I could work on getting this one updated over time.

Andrew

dreracecar

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Re: Modifying a chassis to meet spec
« Reply #11 on: March 11, 2014, 11:12:55 AM »
See what you can get for the whole package, Some people looking into a restoration are more aproachable with the less work and parts hunting the better. If you start picking it apart it becomes less valuble , visualy incomplete to the point that a potential buyer will pass because he cant see the finnished piece.

 
« Last Edit: March 11, 2014, 11:18:36 AM by dreracecar »

Offline andrewb

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Re: Modifying a chassis to meet spec
« Reply #12 on: March 11, 2014, 11:24:57 AM »
If I were to replace the front and rear wheels alone with something comparable, that would cost me at least 3k. I also haven't found a front axle as wide as this one (44") and I really like that look of a wide axle. I'm not so much interested in the rear end though, want to going with an 8 3/4.

Offline andrewb

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Re: Modifying a chassis to meet spec
« Reply #13 on: March 11, 2014, 11:27:59 AM »
What would be a reasonable price if I where to set a reserve for it on eBay, or this site for that matter. Front Borrani 17" wheels, rear Romeo Palamedes magnesium wheels, Old rear (don't know the ratio yet) with drum brakes. 141" wheelbase.

Andrew

dreracecar

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Re: Modifying a chassis to meet spec
« Reply #14 on: March 11, 2014, 01:34:31 PM »
You can buy new front wheels for about $700 and a pair of aluminum rears for the same amount. Going to need new tires anyway and you will kill the value of the rears when you add screws to the rim to keep the tires from spinning.
Front axles are just pieces of tube and I can build them up to the longest piece of tubeing available.

I paid $6800 for mine in simular condition,but it came with complete drivetrain and clutch, also had some history to it which is why I paid that amount. would have paid more but I did not buy the rear wheels because they were drilled for screws.

A few weeks ago on the HAMB board in the wanted classifieds someone was looking for a CC project. mine was too complete/finnished for what I think they wanted to spend