Started building something a bit different earlier this year and i thought i would share it with you guys. Its a 26/27 RPU on a home made chassis, beam axle with parallel leaves front & rear. 130" wheelbase, running a 454 which will be fitted with 6 carb cross ram once its finished. Front end is just tacked in place to get ride height right but you'll get the idea. Its a bit different but its progressed enough you can get an idea of what it will look like. Hoping to be on the road in a few months time, which unfortunately is too late for our summer!
Its very rare, an Edelbrock X4 for rectangular port BB chev. Its drilled for the six holley94/stromberg 97's but i suspect they left the factory with the top blank and undrilled for racers to drill to suit. I have never seen another one anywhere! I knew of this one for about 10 years and in a chance converstaion the owner said they were looking for a 4 carb intake for their A RPU, and i offered the complete setup off my old T as a swap, as it was just gathering dust. You can get a Weiand 4 carb intake a lot easier than the X4.
Very cool; one suggestion: Before the self appointed "Scrub Radius Police" show up, bolt a bare wheel on one front corner,set it on the ground, and take a pic.
Yes,I guess "scrub radius" is used two ways, one relates to steering geometry and wheel offset, I was thinking of the other which relates to ground clearance with a flat tire. The logic being, the frame shouldn't touch the ground if you have a flat tire. Common complaint with the anti-underslug crowd. Scottyknuckles caught a bunch of unnecessary static for that.
Just figured out how to use photobucket and post pic's properly here so i thought i would go back a few steps and post some earlier progress shots. Basically theres about 7 months work in this to date and hoping ot have it going/driving if not legal in April. These are from April/May 08, got the body, played around mocking up to get a vague "feel" for it. Engine & trans a few months later (need to save the $$)
Bought a heap of 75x50x4 rhs and cut up a chassis. I have had the plan for this for a few years and had drawn it all up. rear end is a complete 8" unit from unit a Jap import and chassis was built to accept it complete with stock leaves, shocks etc which should make for easy maint later on. Chassis was also built to suit the body cut & lengthen that was planned.
I'm planning on driving the wheels off this once it's going so loud pipes full time were out. The plan is for headers that i can un-cap when i want but be able to run quieter for daily use. With this in mind i wanted to run a decent exhaust under the car which given the planned ride height if 5" or so would take a bit of thought. First problem was trans cross member. I notched the RHS, ran a peice of 50mmx10mm full length, welde the ends, plug welded it in the middle and boxed the nothced area, nice & tidy and room for pipes, if a bit different. For the engine mounts i used some leaf srping bushes and had some pipe machined to suit, and made the mounts out of 5mm plate. End result is an engine that is virtually solid mounted but the bushes should take a bit of the vibes out??
For the headers i had a local bike shop roll me up some megaphone cones, 2" to 4", 24" long, bought a 2" u bend, a couple of feet of pipe and after a lot of procrastinating started drilling 2" holes and welding it all together. Passengers side taking shape The tricky part is making the other side look the same! Drivers side sits out from the body a little more to make room for cowl steering. Almost done
The plan is to run a full 3" system which was never going to fit under/thru the trans crossmember, so i notched it to allow clearance for something a bit different. I cut a peice of 2" lengthwise and added 4 1/2 inches to it to give me a big oval pipe which will run thru the notch. The flexible "bellows" at the front allow the exhaust beyond it to be solid mounted so everything can run real close and not rattle or hit anything drill some 3" holes in the headers and join the bits together and it all fits in there nice!
Yep. It sure is wild, adds another 8" of height over the stock one thats on there. Got some nice old Cal Custom rocker covers to go with it too, should look good once they are all on.
Working out how low the front end was going to sit and how to mount it? Temp leaf spring mounts tacked in place so it was all rolling, and i could get a feel for how much the front springs were going to drop etc. Looks good like this, nice & low! Looks good from the rear as well, the body had just been cut in this shot and widened 4 1/2" at the rear
Long & low, with the leaf springs front & rear the wheel base gets pushed out a lot. Its right on 130" as it sits, should be nice & stable, and predictable if/when the rear moves around under aceleration!
I figured with a six carbs 454 and 4.11 gears i would be going through a bit of fuel, so i got a tank from a light truck which fits nice in the back. Made up a cradle to hold it from some 30x60x1.6mm rhs i had. 17 closely spaced cuts with the grinder, bend it round, weld it up and grind it up and it looks OK, follows curve of the tank just right Tank holds about 110 litres, or about 29 US Gallons, which should keep it going for a while! Tank cradle will also serve to mount the exhaust tail pipes
Hi,that front end is a bit"avante Garde" isn't it? How does it work and where did you get the design from?
hey man wicked biuld ive got 2 suggestions for ya 1 on the rear suspention you might find it an idea to put a panhard bar or triagulate pan hard bar set up cuz i dont care who says it but even leaf spring rear ends move around it would stop it from movin on decel.also something that would REALLY make that intake of your pop is a set of scott tops for the strombergs and there a guy on E-bay who make repro's of them and sells em cheap. wicked job so far my 2 cents
I love underslungs,and I think your build is cool.This thing should ride like a caddilac and corner like a scalded cat.
Underslung idea was around from the 20's, popular with the "sports cars" of the era. With mine i have designed it myself, had the front srpings made to suit, they are a bit shorter than i would have liked but any longer would have pushe the wheelbase even more. There has been a few changes since these pic's, the temporary mounts were a bit "agricultural" and it looks a lot better now. Will post some more pic's tonight.
The weight of 29 gal of petrol held up by only the ends worries me a tiny bit - maybe consider adding a strap or two in the middle of the gas tank? 'Twould suck indeed to bend /rupture your tank from hitting a bump with a full tank.
Because the Panhard Bar swings through an arc, you would risk creating a bind, depending on the amount of travel. The only factory parallel leaf suspension to run a Panhard Bar was some shit box Chrysler Mini Van.
I know what underslung is,i have worked on cars such as a Veteran called an "American Underslung" and Prewar 'Singers' From the UK, but I wouldn't be happy with the way he has designed that. I a was asking where he got the actual design from. I don't know if you have ever seen (as an example) the front leaf suspernsion of a 1938 Chev . They had one shakle on one side designed to allow suspension variation while attempt tp maintain castor angles. In his design he has very long shackles which will give very long spring travel. This may work on a rear end but we are dealing with a solid front which is going to be pulling up wards . The Possibility of geometry changes is going to be a very real one causing castor changes,something which can be difficult to drive with at speed. What are your thoughts on this?
Cheerrs Gudgyz,see my reply to Unkl Ian above. regarding your tank,those mounts are way stronger than my daily has. It has a 120 liter tank and the mounts are two little 10 mm bolts on the back and 1 each side. it's designed to send the tank out of the car in the event of a rear ender. It's factory and if Mercedes can do it this way it must be OK.
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