I'm Gonna Build A Dragster!

[48fordnut]

Bob W you did good. read the whole post.Afull suit in the sun is what you expect,get a towel over the top of the car for shade. works well. I sold my new /old fed 2 mos ago and miss it dearly. Keep up the good work. you are a great fabricator.

 

[The Spirit of 58]

I would love to build an Old Slingshot

 

[cornfield customs]

if you want a old slingshot, let me know i build replica chassis research frames

 

[The Spirit of 58]

Ill probably look into after the new year probably over the summer.
I don't have the cash currently.
Ill contact you though

 

[bob w]

After a year at the machine shop I got my slant 6 block and head back. The quality of work is excellent. This is not an all-out race engine. Just a mild hop up to check out the chassis and the driver.
The most notable mods are .100" milled off the deck and .050" off the head, for more compression. And a reground cam. The head has oversize valves and pocket porting. I'll be gasket matching the intake and exhaust ports.

 

[ratty 46]

If I can ask .... what took 1 year at the machine shop?? Did they cast the pieces themselves???

I love this build.

Just asking.

RATTY 46

 

[bob w]

Engine Cost, Questions Answered

Cornfield: I think your frames are outstanding. I have been doodling on how to make it NHRA legal.[S Because of my nature I'd have to build one myself. That's where the fun is for me.

ratty 46, my friend runs an auto parts business and machine shop. The shop work takes second place. And, I don't push him whereas other customers do. That means I keep getting pushed to the back of the line. He figures that "Bob won't care". I finally got a little impatient and he finished the work. Because of how long he took he cut the bill in half. Not what I wanted & I'll find a way to pay him in full.

I'm only a year behind schedule.

So here's the deal: I spent about $1,600 on the engine. No one thing was very expensive and it is far from a full racing engine. It probably has around 250 hp. An alternative would be to buy a used small block Chevy engine from Craigslist and have 300 hp for maybe $250. Could probably have 400 hp for the money I spent on the slant. Is the uniqueness of the slant six worth the expense? I don't know.

 

[bob w]

I got really tired of doing bodywork on my '40 Plymouth truck, which will be the tow car for this dragster. So I shifted gears and began assembling the new engine for the dragster.
I cleaned and recleaned the block, set the main bearing shells in place and dropped the crank in. It didn't turn well. I put the main caps on and torqued the bolts. It turned, but was very hard. The bearing clearance checks out at .0015" with Plastigage.
As you can see by the pic of the bearings the problem is in the dimension across the parting line of the block and main caps. See the shiny spots.
I filed a very small chamfer on the bearing edges, main cap edges and main journal edges in the block. Then I used Scotchbrite on the backs of the bearing shells and the main caps and main journals in the block.
After all this, the crank turns acceptably. But, I'm nervous. So I took the crank back to the shop to have it ground to the low limit of .0025" on both the mains and the rod journals. Hopefully that will keep this thing from spinning a bearing.
Any advice or opinions on this deal would be appreciated.

 

[rainman]

I didn't go back and look, but was the block align bored?

 

[bob w]

rainman, the block was not align bored. However, the engine was a runner and turned freely when I disassembled it. I'm going to borrow a telescoping gauge and a micrometer and measure the diameter across the parting line with and without the bearings. Hopefully that will be revealing. I'm suspecting the bearings are slightly out of wack.

 

[rainman]

That should tell you, I suspect you will find an align bore is needed!!
At least thats how I would read those bearings.
But I hope you're right and it's a bad set!!! Good Luck!! Let us know!

 

[bob w]

At long last, I started assembling the slant 6 engine for the dragster. This is not a "full race" engine as I couldn't afford to go all out. I think of it a sort of a training engine. If the car works out well and is fun to drive then a bigger engine will be built.
The crankshaft problem appears to be resolved with an extra half thousandth polished off and a little dressing of the bearings on the parting lines.
The chassis will go on a diet and I might revise the roll cage for a better appearance. This will be one of my winter projects as, even though it is warm and beautiful right now, it won't last much longer.
Let the winter building season begin.

 

[donsrods]

Bob, I just went back and reread all 9,000 pages of this build and it was fun all over again. With that new motor you are going to have even more fun in the future. Great job, bud. [cl

Don

 

[bigd4xman]

I'm into the dragsters as well, but I will be starting on a FED or "slingshot" in the spring. Working on gathering tools, getting the shop ready, buying a few parts here and there and getting the bugs worked out of my 65 F100 that will be the parts chaser and tow rig.

 

[bob w]

Occasionally an RRR member will mention being burned out on a project. Well, I need a break from the Fiat build. Since I fed turkey to a lot of family members yesterday, I asked their help in digging the dragster out of the back garage and pushing it around to the front garage. Kinda looks like a race shop now.
Don, you should get an award for reading this entire thread.
bigd, there's times I wish I had built a slingshot instead. Have looked at changing this one but would be easier to start over.

 

[bob w]

There's quite a few small changes I want to make this winter. First the front will be lowered 3". That causes an interference between the crossmember and the tie rod. Today I made a new, well perforated front crossmember. It will mount a little farther rearward & the yet to be built suicide perch will have to reach a bit farther. The uncut '34 Ford wishbone hangs very low in order to have 15 degrees of caster. It will be replaced with some home made split bones.

 

[rainman]

Have you ever figured where caster would be if you flipped the wishbones?
Thats the way I have them on my truck!

 

[bob w]

Here you can see how high the frame is in front. The rear of the wishbone is about 3" above the floor. It slightly hits the back of my trailer when loading and unloading. Plus it looks bad.

Good idea rainman. However, I have a young friend who is working on a traditional '34 Ford hot rod. He needs the wishbone so I'm donating it to him.

 

[hotrod preacher]

[dr......... never ceases to amaze me at all the cool projects you are working on..and all at once!

 

[rainman]

It had been a while since I had looked at you're dragster. Had not noticed they weren't split![P