Sheets & Giggles

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Not a lot of progress to report. I've tacked in the crossmember/rear drive shaft safety hoop but am struggling with how I'm going to make this thing pass SFI Spec 10.3 now that I have the book. All the specs and diagrams they give are for modern round tube chassis. I am even thinking about going to left hand steer (Spec 10.4) but am not sure how I can put the mandated X into the frame and have it clear the transmission and driveshaft. The modern cars have a much lower bottom frame rail and the trans sits above it thus making the required crossmembers pass underneath.

If anyone has photos or ideas on how to satisfy the requirements I could really use your input.
 

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Thanks Bob. I have planned for this type of tunnel to fit into the driveshaft hoops front and rear. I have already tacked in the rear hoop as shown in the pictures I posted. The problem is putting in the "X" or "K" or diagonal crossmembers that are required as they would interfere with the driveshaft tunnel if I try to install them on the same plane as the lower frame rails.

I think I might see a solution now as I continue to study on the problem. Maybe this is just a case of to many trees in the way so I can't see the damn forest!
 
Can you go peek under some cars that are already compliant? See how the other kids do it. It seems to me that the hoops and tunnel will be considered part of the K, or X or whatever. However, I am no expert. Doesn't the $38 rule book have any examples? I guess not, or you wouldn't have to ask. Right? :D I always put pictures in the manuals I write. Mechanics like pictures.

I'll be interested to see how this works out also.
 
Can you go peek under some cars that are already compliant? See how the other kids do it. It seems to me that the hoops and tunnel will be considered part of the K, or X or whatever. However, I am no expert. Doesn't the $38 rule book have any examples? I guess not, or you wouldn't have to ask. Right? :D I always put pictures in the manuals I write. Mechanics like pictures.

I'll be interested to see how this works out also.

Unfortunately, no one around here has a car anything like this that would certify to run under 10 seconds. The local altereds and funny cars are late tube chassis cars and that is the only type I've had any experience with prior to starting this project. The drive shaft tunnel is an NHRA/IHRA rule and is not covered in the SFI specs. Any illustrations in their book are current tube chassis. There is very little reference to rectangular tubing other than in the material list which gives a minimum standard of 2" x 2" x .058" square tubing may be used for the lower frame rails. All round mild steel tubing must be minimum .118" wall thickness.

Anyway, with that said, I think I have figured out how to satisfy the rules and keep the project going.

By making the transmission crossmember out of 1 1/8" tubing and moving it forward to right behind the transmission mount I can do a "K" member from the middle of the trans crossmember back to the rear crossmember. I think I will then have room to mount the forward drive shaft hoop in the center of the "K" member. This means that the trans will have to be installed and removed from the top but I can make a quickly removable crossmember to mount the steering box and thus make the room needed for installing/removing the transmission.

I hope this explanation makes sense and hope even more that it will work. I'll find out this weekend and post pics if I'm successful.
 
Sometimes little things can make me quite happy! :D

Here is the steering box I picked up for the car. P-S Machine Products out of my buddy's funny car. He's upgrading but his cast off is plenty good enough for me - especially at less than 1/2 the price of new.

The steering will be very quick though with just over 1 1/2 turns lock to lock.
 

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Nice piece. Shold be worth 2 tenths.

Gee Bob. Is that all? I was hoping for at least 1/2 a second. :D Guess I'll need to get the coffee can mufflers and four square feet of decals to go that fast though.

Actually I really don't expect the car to be very fast .. mid 8's at best with the blown 383. I just hope it turns out to be fun and safe to drive. So far the build has been a lot of fun. I have high hopes to be bending some pipe this weekend but we'll see how it goes.
 
Shoulder bar

Got the shoulder bar made and positioned. Been a while since we used the bender but it all worked out good. Unfortunately the "joint jigger" was out of commission so we couldn't make all the uprights. Won't be able to do the roll bar until I finalize the seating position and know how tall it has to be.

Huge thanks to "Saxxon" for helping me today.
 

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Looking good so far. I worry about making a bad bend and wasting tubing.

I'm guessing mid 8's in a short wheelbase Altered will command your full attention. Looking forward to watching you run it at Byron.
 
Sure hope I make it to Meltdown but I might have to pick up the pace a little to make it with the T. The Scout and the Prefect are already registered so we'll be there for sure.

Made it into the shop today and got a transmission crossmember fitted. Didn't have time to do the "K" member I have planned - hopefully get that done tomorrow and also find the missing parts to get the joint jigger working and make easy work of the uprights.
 

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Got a bit more done on the chassis. Fishmouthing the tubes is a little more time consuming without the "joint jigger" but happily "Saxxon" was there to help. Here he is touching up one of the uprights. The work goes quicker and is more fun when there are willing hands there to help.

We got all the uprights made and tacked into place. Also got the "K" member fitted. There is lots of room inside the "K" for me to mount the front drive shaft hoop and the tunnel. Sure glad that worked out. :)
 

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Continuing to work on the chassis. Got the diagonals, seat back brace, seat front bar and the front driveshaft hoop fitted. Starting to look a little more like a race car. Should be able to finalize seat height and get the roll bars bent and fitted next weekend I hope.
 

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Not really a whole lot to show this week but I guess a little progress is better than none. It is now a dual rail chassis as required by SFI specs for 7.50 certification. I hope to put in the last diagonals tomorrow and the firewall and roll cage hoops soon.

I did get confirmation that my 80a pump will deliver enough fuel for the 383 / 671 blower / enderle bug catcher setup to run on alcohol so the appropriate pistons have been ordered. Should work out to about 10.5 - 11 to 1 static compression. I am going to limit the blower to 10% overdrive which should make 12 - 15 pounds of boost. This setup will be testing the limits of the factory 4 bolt block so it should be fun. :D
 

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You are moving along smartly on the build. The double rails look a lot more businesslike. You know, 7.50's is getting down there in Winged Express AA/FA territory.

I'll be using a double round tube frame for my Bantam body even though it will be built to 10.00 and have a passenger seat.
 
I don't expect to run in the 7's Bob but that is the certification break - there are certifications for 5.99 and quicker, 6.00 and slower, and 7.50 and slower. Slower than 9.99 does not need a certified chassis for NHRA but a roll bar is required for anything quicker than 11.49.

As I said before, I hope this thing will run a mid 8 but I won't know for sure until I get the timeslip. If it does perform close to what I hope it should make a decent show for the folks at Meltdown and thats all I'm really trying for. After all, it is being built just for "Sheets & Giggles". :D
 

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