Projects Two gun guys build a front engine dragster

Long-time lurker and occasional poster but let me say the site is excellent and been a very big help.

I've been wanting to build a FED for a couple of years now and finally scraped up enough change to start on one after selling my mustang project (homebuilt turbo 5.0)

This is probably about as cheap as someone without a garage of speed parts could put one together so try not to laugh



Browsing ebay turns up the bugcatcher hat, found the 6-71 on craigslist some guy had on a boat, lower intake was a swap meet special.

So far more expensive than a lot of motors I've built and its only the top end



racingjunk find on the shorty powerglide, another craigslist deal on the 350 4-bolt longblock. $100 for the longblock and a stock alternator and starter . . . so far chevys are indeed cheaper



Finally make it to the shop . . . a guy I work with (we work for a firearms manufacturer) builds motorcycles on the side and has a full-blown fab shop. I had been bugging him for months to help me with a frame and he finally relented



Chalk line'd, craigslist 9" that appears to have been pulled from the bottom of a lake, some strange guts for that 9" . . .



Two steps forward, one step back for a couple of weeks . . . bought 95% of the tubing I needed from shapiro and only got the minimum wall thickness (.058) well the hossfeld bender said to heck with that and we crushed the first tube trying to get the bottom bends.

Finally went to a shop that had a hydraulic setup for their hossfeld and bumped up the tubing to .065" and no problems.

138" wheelbase.



We've got no blueprints or pre-made plans, only the SFI book and some printed off images from google . . . which might explain the frame for you actual dragster builders out there.



The future home of the meat in the seat.

Right now we are on the almost every saturday/sunday plan . . . hope to wrap up coping the existing bends and throw together the cage section.

I am a machinist at work so I've got a little work to do after hours machining two spacers for the spindles (apparently strange stilletto spindles and a s&w front axle don't use the same length king pin boss) and machine out a plug for the center section to line the motor up with a tube through the main caps.

Any words of advice . . . feel free to share them. I've never built a car from scratch let alone something I've never worked on like a FED but I've worked with an alcohol funny car if that counts

Guy I am working with used to work for Pat Patrick Racing, then for jackie howerton, then built midgets, then built motorcycles . . .

 

Wow! Very cool....

 

Looks like a good start. Keep us posted.

 

subscribed!

 

Hey Tyler - Awesome project.

 

I'm guessing the tubing is "Chromoly."

pages 20.20 thru 20.23
http://www.nhra.com/UserFiles/file/General_Regulations.pdf

 

Good start. Just a suggestion. After have driven a few RED's in the 60's, you have the engine and rear end too high in the chassis. If you try to sit in the car your legs would have a hard time going over the rear end. If you move the seat up, to help this out, your head will be over the roll bar. I would move the chassis up 3 to 5". Hope this helps. rj

 

lookin good!

 

I have a rear end bar if you need it! I am right near you. I sent you a PM. Later - J

 

If you do not mind get a set of Mark Williams plans (Believe you can purchase plans seperate) great shop and parts.

 

i have never scratch build one, but have worked on a some. it looks like your rear end and drive train is too high, and id look into the thickness of your tubing.

most cages must be .120 wall or .083. i know you're probably not concerned too much on nhra rules.

 

Interesting story... Subscribed!

 

I like the way this is going......cool build.

 

Ditto on driveline height. Cool project for sure...

 

Your top rail is too low, it need to be raised a good piece.
Mark williams sells the plans very reasonable, just get them to confirm the dimemsions are on the plans. I might be wrong, but i seem to remember that they sold the plans in two ways, if you buy thier kit the plans have dimensions and if you just buy the plans they forget to put the dimemsions on them.

 

very much so . . . SFI specs 1 3/8" x .058 as the minimum wall for the main tubes for chromoly (7.50 ET and slower), if mild its .118" I believe or something ridiculous like that.

We were worried about that . . . going to try and sort that out tomorrow as my builder worked on it last weekend while I was out of town.

Do you (and whomever else) use a table for a jig? The ground clearance is set in the 4" range under the bottom tubes and right now the pan is level with the bottom tubes (hence them both being on the table).

Are you saying bring the top tube down some and set the motor down?

Trying to get the dump angle I want, figure out ground clearance, and figure out the rear end height has been the hardest part of laying it out since we don't have actual plans to go on.

Looking again at some pictures (here in the FED thread and the mark williams plans) seems the notches for the motor plate are almost inline with the rear and judging from my pictures (shop is 30 min away from here) it looks to be 3" or so above the centerline of the axle tube.

My only questions are then: What do you guys run for ground clearance on the tubes and on the pan?

 

Three inchs of ground clearance , bottom of pan can't be lower than lower frame rail, I agree with eveyone on the rear height in the chassis, set up like that you would feel like you were sitting in a bucket, you want to keep your limbs in the frame rails looks like your knees would be exposed, looks like a great start Tim Jones

 

Tyler the more I look at your pics, it looks like the nose of the motor needs to go up, that should drop the rearend down maybe one of your square blocks , hope that made sense , still would need to raise your shoulder hoop up a bit

 

Yup, figure out what size wheel or more importantly tire height and mock it up. With that short of a WB you can get away with a few degrees motor dump. This will allow you to set your rear end at the correct chassis location. There are a couple build threads on the HAMB that address this process.

Look up "Front engine dragster how to build one" by Brian at King Chassis
http://www.jalopyjournal.com/forum/showthread.php?t=452462

Some very fine dragsters have been built using less sophisticated jigs/tables than you have. I struggled for a long time trying to figure out how everyone else did it (build in general) and for everyone I asked I got a different answer. Keep at it and you will get it done.
Expect that blown motor to be a handfull in that short of a car.

 

nice start. someday i hope to build a blower motor but not cheap as you found out. not even used parts.

 

It looks to me that you have sorted out the rear tire height and that is where the rear is situated, right? So that part cannot change, ok? to set the engine then its' oil pan cannot be lower than the bottom frame rail and you need the proper pan depth - i generally set the crankbolt at about 11", check that against what you have and you might nnot be able to get that low but you should be in that range.
The engine will run uphill into the rearend - do not set the engine level - both engine and rear end are fixed and the driveshaft is a solid coupler going into the rear.
Now you know where the rear is situated, where the engine is situated, where the lower tubes have to be so the only unknown is the upper tubes, right? Hop in it and the upper tubes should surround you just above midway between your elbow and shoulder with arms at your sides and it will continue to raise so that your shoulders rest against it when seated. Now you need to figure out your kneebar height, i set that one accordin to whether i want the far tire visible from the near side - the knee bar sets the height of the cowl panel, if it is too high the car will photograph as if it has just one tire and i prefer to have the hump of the 2nd tire.
You have to satisfy the purpose of the kneebar as well, it is intended to retain your legs inside the car in case of a mishap, it is also the bar most set the switches etc on use it as a dash panel. The steering box will be mounted to the hoop that supports the midplate, some people support the steering colum on the kneebar, i prefer not to as a properly mounted box will support its' own shaft with a column. then kneebar can be bolted and kinda hinged so that a couple bolts remove the steering, pull a kneebar bolt and the whole space opens up to pull tranny straight up.
To help you build this thing and really appreciate the job of building it find a funnycar guy esp a chassis builder, and go over it with a machinests' eye - the only real difference is where the drivers' ass is located. The engine and rear etc will be in about the same relationship, a fed you sit behind the rear with tranny in front of you and a funnycar you sit in front of the rear with a foot on either side of the clutchcan and tranny between your legs. Look closely at how refined and the layout of everything, those chassis evolved from the feds/alterds for 60years of improvement.

 

thats the only part I am not tracking on yet . . .

The constants are indeed set -

-The centerline of the rear axle in relation to the ground is fixed given tire height.
-The top tube must be in relation to driver's shoulder per SFI book.

The only things that can change are the angle at which the motor is at relative to the ground and the bottom tube.

What I don't understand is why the pan (other than safety reasons) can't sit under the bottom tube some? Seems like a lot of the 60s FEDs have the blower pulley/crank centerline somewhere in the middle of the top tube and bottom tube which seems like it would sit under the bottom tube some. And personally I would like to have the drain plug on the side sit under the tube so when I drain the oil it doesn't end up on the tube on the way out. Or I guess run some 90* petcock deal.

Going to mess with it some this afternoon . . . thanks for the help

 

First up, there is no requirement for the oil pan to be above the bottom of the lower frame rail. Under "Ground Clearance" the NHRA book states that there must be a minimum of 3" from the front of the car to a point 12" behind the front tire contact patch. That is to allow the timing system to work properly as the clocks start when the stage beam "makes" again as the car rolls forward. The rest of the car must have a "minimum of 2" clearance except oil pan and headers where permitted". That said, it is a good idea to keep the pan as high as is practical.
OJ suggested hanging the steering box from a hoop supporting the motor plate but the more common construction is to mount a crossmember a little further back and make it a bolt in. That way the entire steering package can be swung out of the way to allow the transmission to come out the top of the car. The "knee bar" needs to be high enough and far enough forward that you can get you legs under it as you slid into the seat but it can also be as small as 1/2" tubing and be legal. They say that a picture is worth 1000 words so here are a couple of examples.

Roo

 

Rooman, I stand corrected,( after looking through the rule book again) I thought I read that the oil pan on a dragster or funny Car had to be no lower than the bottom frame rail, But on most of the cars I had and worked on the lower rails got pretty beat up, I my self wouldn't want a pan full of oil hanging down where you could run the chance of grinding a hole in it, most tracks are smooth but the shutdowns and return roads can be alittle rough Talk to you later , Tim Jones

 

Again if you check out the pics of a dragster I drove and owned in the sixties you can see the oil pans are below the lower frame rail. We did have a 1/8" skid plate on the front oil pan. You can put a 3" block under the oil pan, then move the chassis up so the rear end just about sets on the lower frame rail. Then mock up a seat and sit in it puttng your legs over the rear end. You may have to move the seat up or down. Then check location for steering shaft and pedals.

 

Well plugging away at it . . .

Most of the frame is done and mike is getting super close on welding it all up.



My ugly mug



We did decide to move the top tube down 1.5" which effectively pulled the entire frame up 1.5" relative to the motor . . . and dropped the angle some on the motor giving the rear a much better location in the frame (and to me)



I had no clue how big a 5 gallon tank was until it showed up . . . time to get the band saw up and running.



How have you guys set the motor and rear in alignment? Been looking at pictures and the basic idea seems to be some tube with a welded on flange to bolt up to the center section housing. Sound about right?

 

Great build.

As to the alignment there is a jig that bolts to the mains in place of the crank and centers to the pinion on the rear. I built and placed the motor plate on mine without this jig, but my rear was already placed. With a combination of string line, laser level and finally sliding the coupler in and out of the female couple on the rear till it was aligned without much friction I located the block. It worked for me.

 

Tyler,
if you want to pay the shipping charges you can borrow one of my line up bars. If you are only planning to build one car it may be a little cheaper than buying one. Mark Williams gets $295 for his.

Roo

 

Awesome

Lock and Load guys, Nice start

 

Roo,

what size mains? . . . I'm using a SBC.

Let me know on the shipping to 30519

thanks!