Thinking of updating my dragster from 7.50 to 6.0 cert and before buying the cert to realize i'm wasting my time, i figured i'd see if the drr crowd can give me a little detail before wasting my time.

I know the foot box needs X'd. It currently has a 7/8 diagonal.

the floor is not x'd, not sure it needs it? diagonals are 7/8

top frame rail is 1-1/2 and steps down at the foot box to 1-3/8. Pretty sure the spec says where the cage hoop welds to the top frame rail it has to be sleeved/stepped and rosette welded. Someone told me an alternative is has a gusset coming off the cage hoop to the top frame rail. Is that accurate?

Are there more diagonals needed? I'm sure location of uprights determine what can and can not be done.

I know i'm asking a loaded question but any ensight before i spend the massive amount of money ($38 bucks :P) on the spec is greatly appreciated.

One of the most important is the upper cage thickness and diameter also. I just texted one of my close friends. He is an inspector. His RED is a 7.50 car but the issue is with his is the main rail thickness and hoop thickness. Too thin. He stated he has all the specs on his comp but he is out shopping. Either run the 7.50 chassis as is or look for a 6.0 chassis. I can see if he can email me the 6.0 specs specifically. I know when they cert my 6.0, they paste and read,the hoop assmy, Upper frame rails
Cage area, lower frame rails Cage area. Just do a visual on the foot box for the diagonal/x brace. His problem is its an old MW 7.50 car.

Screen name just kills me. LMAO

This message has been edited. Last edited by: TD3550,

Thanks td. I made the screen name well before I bought the car lol

I measured the cage main hoop and it’s 1-1/2 I assume .058 or .065. The top frame rail is 1-1/2 with a 1-3/8 so I assume .058 or .065. Not sure you can cram 1-3/8 in 1-1/2 .065 with tolerances or not.

If your buddy has time to take a look at the spec that would be wonderful. If not no problem I appreciate the info thus far.

Once he is done out shopping with his bride spending his money looking for "Shoes". If he sends me the PDF, I will send you a PM for the Email Addy.

Ya mine. Both sides. 6.0 chassis..



Re squared the car. Slip tube and back in business. Most stressed area there and directly at the back of the seat area. Right before the balancer. HT car. Been a great car tho.

This message has been edited. Last edited by: TD3550,

That looks like a fun repair!

I was told the upper frame tube had to be changed from 1-1/2 to 1-3/4 from the foot box all the way around back to the foot box.

Couldn't find a builder that would do it.....

I have the cert at shop can get it tomorrow but I know I have no 1 3/4 in my chassis

quote:

Originally posted by imakehp:
I was told the upper frame tube had to be changed from 1-1/2 to 1-3/4 from the foot box all the way around back to the foot box.

Couldn't find a builder that would do it.....

That's incorrect. It can be 1 1/2 but it needs to be .058" wall tubing. Frame rails can be 1.3/8, .058 tubing. Cage itself can be 1 1/2, .058 up to 18" tall.. Higher than that must be 1 5/8, .058. I've done this conversion on a 7.50 dragster, it's not that bad but can be a lot of work. Best thing is to spend the $40ish it takes to buy the SFI spec book and read through it. I did, best money I've ever spent. It's been several years since they issued the last change, and I'm guessing it might be a few more before any additional.....

Are you planning on going faster then 7.50? If not it kind of pointless.

that's the whole point of updating it

try to sell what you have, take what you can get for it and start over. Way too much $ and effort to put into an old dragster that if done is still an old dragster.

Ed that would depend on if it actually needs anything I know a few cars that only were carted to 7.50 that would cert to 6.0 but owners didn’t want to spend extra money and the 6.0 cert used to only be good for 2 years

But you are correct if it needs a bunch of tubes upgraded easier to sell and update

I ended up getting a copy from a local that was missing a few pages, so once i get the full spec in the coming days i'll know for sure.