Hey guys, Im doing t he best I can trying to learn about these old cars but there is a lot to learn. I have been working on 60's Mustangs for the last 6 years or so and Im looking to build my first hotrod... This will hopefully be a father son project (im the son), just looking for something for my dad to get involved in and say he has built a car/truck. I have been reading for the last few hours but havent seen answers to many questions...most regaurd frame building, ride height and suspension. We are planning a 30-38 truck cab but we are going to run a mechanical injected cummins 12vmotor. Its a damn heavy motor but Im confident stock style stuff will hold up just fine...it will be a cruiser, no racing, no crazy stuff. I have seen a few cummins later model trucks on 5lugs and they are doing fine. I want to base the frame off an 'A' frame, with 2x6 3/16"... I want a low truck (the cab will be channeled but probably not chopped...dad is 6'2") but I dont want anything crazy where we wont be able to go over speedbumps and stuff... a daily driveable height. From what I have seen, I was sorta planning a 10" kickup in the rear but no clue for the front to match... Im going to get a speedway front mount kit (or is the rear mount better?) with a 4" drop axle... will I need to Z the front to keep it in perportion? The speedway front end said it holds up to 2500lbs so it should be plenty. Last question (as of now ) is on the frame, does the cab mount on the frame behind the taper in the front? Im thinking that the firewall is right behind the bend inwards. Thanks guys
I think you would be bettere off with 2x3 or 2x4 .125 wall tubing for your frame. Did you look in the tech section and do searches for what your looking for.
yes, I have been reading for the past 2 hours trying to find ride height stuff and I have spent weeks looking over just about every tech article. There is lots of frame fab stuff but no measurements, just a how to... nothing really on determining a good ride height, just what they wanted I guess. I was origionally thinking 2x4 box but im really worrying about strength... A cummins 6bt weighs in at 1100lbs fully dressed... I might be able to shave off a bit of the weight but its not going to be much just losing power steering pump/ a/c compressor and stuff like that. Its gotta be 3/16" steel, heck I was almost thinking 1/4" to be safe. Id rather overbuild than underbuild
12V 6BT 5.9 Cummins??? Man that is HEAVY. They do make a 4BT 3.9 liter that is the 4 cylinder version. Would still be plenty motor for a lightweight truck. You can find them in chevy box vans with a chevy bellhousing pattern among other places. THe 6bt is ~800 pounds depending on trim and the 4bt is ~600. Still a heavy engine. Both are very TALL. Not discouraging you, I think it would be SWEET when done! Love that whistling sound!
my goal is big motor, little truck Its only 200lbs, why not go 6bt?? I can get ahold of a 6bt/nv4500 a lot easier
Well hell yeah then!!! You gotta send some pix! I wanted a GE H turbine in my truck the first time I saw one but 536,000 horsepower was a bit much...
WOW! I bet you can find motor mounts & an adapter kit at the local parts house. Just be persistant until they come up with the parts for you! Gary 4T950 Chevy Guy
That would be awesome if you could...i have looked nd looked and never seen a cummins in an old truck.
Aw hell, you still set on that Cummins? For what you could sell that Cummins you could probably finance a lot of other stuff for the project.
couple thoughts on this thing. ~1100 pounds for engine alone is ALOT. especially right over the front tires. You may want to think about some power steering. I would also suggest moving the engine as far back as possible. all that weight in the front and none in the rear will not make it fun to drive. what were you thinking style wise. like just the cab like a modified type setup or an actual truck with bed? with just the cab you will be able to nicely balance the weight. I would think 4x2 3/16 tubing would work ok. with the amount you want to lower the truck you are going to have the motor sticking WAY up over the frame rails. that cummins is TALLLLLLLLL he won't see over it in a channelled/kicked up truck. I don't know how high on the motor the mounts are on a cummins but I would think you have a pretty large motor mount that needs to be built for this as well
I can pickup a used cummins/tranny for $2000 or so...not to bad...Im sure by the time I sourced a flathead and got it going again, Id be over that amount...and its different Motor mounts are no worries for me, I like welding and cutting. The mounts will be made of 1/4" plate. The motor isnt much taller than say a ford 351w with a carb and cleaner on it. I measured the motor in my dodge and its 35" tall if I recall, 36" long from crank pulley to trans mounting surface and 24" wide. Its bit but not as big as everyone make it out to be. found these dimensions on another site for a 6bt length w/o mech fan 34" length with mech fan 38" height 32" width 30" (to outside of the turbo)
You're pretty much in unchartered waters here. I'd say, get the engine and block it up on the floor at the height you want it to be in the finished vehicle taking ground clearance into consideration. Set the cab behind the engine and block it up to the height that you want it on the finished vehicle. Get the wheels and tires you want to use (or at least appropriately sized mock up wheels and tires) and place them where you want them in relation to the engine and cab considering wheel base and track width. Now start taking some measurements and making some diagrams on where the frame needs to be to keep the proportions of the main components where you placed them. It's important to do this on the ground and in an area where you can get 30 - 40 feet away from the vehicle to see how the stance and proportions of everything look.
HERES ONE THING TO LOOK AT... YOU SAID YOU WANTED TO RUN A 4" DROPPED AXLE..... I CAN TELL YOU THAT 1100lb ENGINE WILL EVENTUALLY DROP THAT OLD FORD DROPPED AXLE ALL THE WAY TO THE GROUND. AND IN A FAIRLY SHORT TIME, EVEN THE NEW DROPPED AXLE ARENT BUILT TO HANDLE THAT KIND OF WEIGHT ... NOT TO MENTION THE SPRING RATE FOR EARLY FORD FRONT ENDS. IF YOU REALLY WANT TO USE THAT ENGINE, I SUGGEST USEING A LATER TRUCK LIKE '42 & LATER WITH PARALLEL FRONT LEAFS. JUST SOMTHING TO THINK ABOUT .. 1100lbs IS A HEAVY ENGINE IN THE FRONT OF A LIGHT CAR.
yeah..i was sorta worried about it. My only possible defense would be how much would a blown hemi weigh in at?? Or something like that. Speedways site said it can do up to 2500lbs, I might need to contact them and talk with them
a friend of mine ran an olds motor in his 33 sedan in the 50's and he said he wore out shackle bushings pretty quick with that in there... never mentioned any axle problems...but thats only 600-700lbs? i dont know for sure... good luck in any case Zach
As far as establishing ride height, you really need to get the parts you're going to use in front of you and mock it up. Even if you're using the same components as someone else did on their build, there's so many different variables you need decide on and "build in" as you're actually putting the thing together. I think this is why you're not finding a "written in stone" example of getting a certain ride height. Pick up a few books on building hot rod chassis, that'll get you started. Sounds like you have a good idea of what you want to do, and seems pretty cool to me. Speaking of overbuilding though, I think I'd use a parallel leaf front end with that setup! Cheap insurance! Good luck!
THANKS FOR THE ADVICE!! Im really thinkin the parallel leaf is becoming the only way to go now that I look at it. I think it with a Z'd frame up front will get it closer to where I want..just not a pretty. Any suggestions on a book to pick up?
found another site that lists a cummins at 908lbs without the accessories. so really that's not quite as far off as we thought. solid ford I beam (say 32 ford heavy beam) would be PLENTY stout for that. (olds and hemi motors are in the 740lb range stock) I think your biggest concern will be a beefier spring in the front.
motor placement matters, as does spring arrangement. I CERTAINLY would not use a suicide front, I'd use parallel leaves, or at the least a spring over arrangement with HD shackles, larger mounting hardware. Placing the motor towards the back will relieve a lot of the stress over the front and help it handle better.
I have been reading more and more today and found that a 331hemi is pretty close to the same weight... Here is a thread where they were sayin you can run a Poise HD front spring. Only accessory I plan on running is an alternator...no a/c, no power steering, no emissions stuff... http://www.jalopyjournal.com/forum/showthread.php?t=127631&highlight=parallel+leaf and I have to point this thread out because the car is beautiful...running a buggy spring with a 331 hemi http://www.jalopyjournal.com/forum/showthread.php?t=112151&highlight=stefan
I agree..I want to move it back but its sorta long... I plan on stretching the frame about 8-10" over stock for a little more room and it will be back about 1/2" to 1" from the firewall. Theres no way I'd do a suicide front..heck, the name scares me anyways I like a spring over (its the one that sits under the crossmember correct?)
You might what to rip off Jay Leno. I know he didn't build it, but I can't remember who did. You wouldn't have to have as good of metal shaping as this to pull it off.
That car is called the "Blastolene Special", I think the motor was from a tank. Heres a link of the build. Got some good shots of the frame etc. http://www.blastolene.com/The_Special/index.htm
Is this to be an open engine rod? Man, I hate to steal your thunder, but for a first hot rod, you are taking on some design aspects that might not lead you to the asthetics or performance you really want. Building one takes a lot of discipline to see through it even when its tried and true methods and design. I understand wanting to stand out with something different. As already said, your frame and suspension will need to be heavier than most rods. Have you drawn out what you are picturing? That helped me a lot. At least you aren't building a frying pan!
LOL...the frying pan was... interesting Its my first hotrod but I have been workin on cars for a while. Not really lookin for performance, just something different and fun. Its not a question is it gonna happen, its a matter of time.
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