Mario Kart Update (aka DuroPower)

[Denny]

Glad I could help you out. Fun fact: When the Ramhargers drag racing team (Group of Chrysler engineers backed by the factory) was first starting out they ran a megaphone exhaust on their first car. They were hoping for better exhaust gas scavenging. Kind of like a reverse supercharging. It worked, only too well. At speed it not only sucked out the exhaust gasses but part of the intake charge also. These are the guys we have to thank for tunnel rams and 426 hemi engines

 

[snowjob]

That is awesome. He is gonna love that history connection as he is already planning a project car El Camino with a blower sticking up through the hood.

 

[madprofessor]

So impressed that I forgot and overlooked the hand controls.
Time will tell how it goes, but I'd bet my bottom dollar you'll end up wanting at the very least some kind of heel rest to keep your feet planted while turning and bouncing and etc.
Maybe slide-adjustable for different kids and adults?

 

[madprofessor]

Just saw your post Denny, and oh Denny! A fellow Mopar fan! And Hemi buff at that! Lifelong Mopar addiction for me.
Just saw the Plymouth pic too, and I can imagine the excess vacuuming on the exhaust. Thing is, all the old gassers were running their headers out of the same place. Wonder now if it was costing the Mopars some power............

 

[Denny]

Nope Tom Hover and the boys figured it out pretty quick. Oh yea they gave us the science for tuned headers. Actually I am a GM guy who hung around with a lot of Mopar guys and knew a few Chrysler and GM engineers who drag raced a El Camino, 63 straight axle Nove ss who happened to own a 67 Plymouth Belvedere, and a 1970 Plymouth GTX b5 blue, air grabber and white interior.

 

[madprofessor]

I'd shave my butt with a chainsaw to get just a stock '70 GTX.
Factory 440ci on a Torqueflite automatic, sweet as factory candy gets.
To this day my favorite ride was my 1973 Plymouth Barracuda, even with the stock 318ci (my favorite factory motor, have had 3).
Its rear end was the best looking of any of the pony cars, except for that 1970 GTX. That thing's slicker'n a skint di_k with sunglasses.

 

[snowjob]

You crazy Mopar guys. I worked for one back in college who had a bunch of old Power Wagons in his yard. I recall him finding a 1955 Imperial with the original 392 (I think) hemi for $1000 and helping him resurrect it and drive it home. It had a fresh oil change and then sat parked for 10-20 years. We blew out the fuel line, fired it up and I got to drive it back to his house. That car was massive! He mentioned lying on the rear deck during family trips. I also think it had push button transmission.

Back to our build, look what arrived yesterday.......



I have a few days off coming up so hopefully we can get the exhaust fully built.

 

[snowjob]

Oooh, I almost forgot. The Boy says if the vacuum effect from the cones does pull the intake charge all the way through, we are obligated to install spark plugs in the exhaust system

 

[madprofessor]

Uh huh, I know what he wants, the little showoff. If he wants it to be a flame spitter, might as well put an oversize main jet in it to get more raw gas into the exhaust.
Assuming those cones are painted sheet metal. How are you going to treat the seams? I see the small gaps.

 

[snowjob]

I plan to weld the seams using a copper back plate. That should allow me to grind the outside flush when done.........or I could use this as a chance to try my TIG welder (bad idea, but very tempting). They are just plain mild steel, as is all the tubing. Just plan to polish them up and leave them unfinished other than a coating of WD40. Just don't ride in the rain.

 

[madprofessor]

Copper backing plate............do you mean soldering the seam flat and sanding smooth, or actual welding with that bead to grind down?

 

[snowjob]

MIG welding using copper on the backside of the seem. This keeps the bead from entering into the cone, which would be harder to grind down. Then I can grind the bead on the outside relatively flat. The copper is only used while welding.

 

[Denny]

Snow job I like the way you’re kid thinks. So many kids nowadays can’t think straight.

 

[madprofessor]

Wanted to try my TIG function also, make some real pretty joins, and the add-on kit for my 120v. Klutch stick welder is only $100.
Unfortunately the required Argon regulator/flowmeter is another $85-$120, and the initial exchange bottle deposit is about $175.
Want to learn the skill, not willing to sacrifice my firstborn child for it.

 

[snowjob]

Yeah, getting my TIG rig ready has been a long, slow, super-expensive march. I picked up a Lincoln 175 a very long time ago, had to re-buy a tank/gas due to an overseas move and get 220V run to my garage. That only took 10 years and lots of Benjamins. If it weren't for a broken back three years ago slowing me down, I would have started using it by now. It's just that each project comes up and the MIG is so quick and easy, I just keep putting it off. I am nearly out of gas on the MIG and it needs a new regulator, maybe that will finally push me over the edge to start TIG.

And my son has been scoping out his next project already:

 

[madprofessor]

Spent lots of Benjamins? Hah! Better get a Benjamins printing press if restoring that piece of a car.
About that Imperial...........
Granddaddy always had Chrysler Imperials since when I was a little kid. Even way back then, the technology was amazing for the time...........
By the earliest 1970's his Imperial had auto-dimming headlights, temp-set A/C-heat climate control, and a squeezable steering wheel that would blow the horn wherever you were holding it. And oh yeah, neck-snapping acceleration.

 

[snowjob]

I knew we would have air cleaner space problems, but it is close enough that I think we need to sort it before fabbing exhaust. Any ideas on downdraft carb or elbows before or after carb?

 

[Denny]

Impala, Impala, I have a 67 Impala SS327 convertible, marina blue poly with medium blue bucket seat console interior. My best advise is get the most complete car you can. Especially for a first car. Parts ain’t that easy to find for them.

 

[Denny]

You could make an elbow to turn the carb.

 

[madprofessor]

Can't see the intake adapter well enough to tell if it's flat-faced or a curved venturi, but believe me it really matters a lot.
Seems that a flat-face adapter with all the turbulence it creates even from a direct-to-it airflow would react poorly to coming at it from an angle as with an elbow on it.
It makes sense that a venturi-face with its thin leading edge would sustain a less turbulent airflow than the flat-face if you have to put an elbow on it to clear the exhaust. The less turbulence under negative pressure, the greater the volume of airflow, ie; more hp. for you.
BMI sells a black "PKT clone aluminum filter adapter" for $17.95 (#TDKM190) that's correct, and not to be confused with one they have with "tapered inlet", that one's still flat-faced garbage.
If you've got or get the right one (all Predators really should have them and a hi-flow filter), you'll have to craft an elbow. Just make it as huge as you can.
One exception: If you look around for pics of Mikuni carb upgrades for Predators, the best answer I've seen is a 90-degree curved version of their common "velocity stack" adapter.