I'm Gonna Build A Dragster!

[sgtpontiac]

Makes perfect sense.....

An old trick on our roundy round cars was to make the exhaust long, 3 or 4 feet, run it hard then look were the discoloration on the pipe was!!
And cut it there! Theory was thats where the backpressure was neutral,
and where you'd get the best effect!
Not sure I explained this correctly but it really did work!!

I always had some header collector extensions around...could kind of tune it for the location....bolt on a shorty, longer longest....it worked....caught my floor board padding on fire (smoldering) one time...probably should have removed the carpet!!!..

 

[rainman]

I always had some header collector extensions around...could kind of tune it for the location....bolt on a shorty, longer longest....it worked....caught my floor board padding on fire (smoldering) one time...probably should have removed the carpet!!!..

Ha ha ha.....
Yep, right were the discoloration is is where the exhaust will flame!!
I haven't cought anything on fire, but have gotten some serious hot spots before!

 

[bob w]

Thanks for reminding me about how to determine collector length. Even though I am sicker than a dog, I cut up the sbc right side header. Had to make more cuts in order to use the tubes on the left side. The silver collector is from an old set of headers I built for my Anglia many years ago. Got to do some blacksmith work yet to change them from 4 into 1 to 3 into 1. Tomorrow I'll get the front collector switched out and get everything welded.

 

[rainman]

I wasn't sure I was going to like it, but it's looking pretty good!!
Looks lik all buiseness!! Squeeze everything you can out of the little slant 6!!
You plan to run them into one collector, or keep them seperated?

 

[rainman]

I do wonder what effect having those long pipes right off the head before it bends will have! I've never seen any headers like that before!

 

[48flatbed]

Headers

Looking good Bob! I would rekon the longer primary tubes would help in low end torque. Might be just the ticket to get off the line hard!
Jon

 

[bob w]

When I started I thought the header was going to be butt ugly. Now, I kinda like it. Lots of stuff to look at from this view.

Rainman, I'm far from an expert but I think bends in headers are to make them fit the application and to achieve equal length. There's no other performance advantage to having bends. The slant six configuration is what caused this unique arrangement.

The intake manifold and exhaust header are all one piece. Gonna be pretty unwieldy when removed. I might have to use an engine hoist to set it all back in place on the engine.

 

[rainman]

Yeah, you're right, but just as in port work in a head the flow can be changed to increase or decrease speed, with bends and different length tubing!! My guess is, (and it's only a guess)
that those straight sections comming out from the head will have some type of effect on flow!
It's gowing to be interesting to hear how the exhaust sounds when you get it done! You may have to give us a listen!![cl[cl

 

[bob w]

The header is done. Total cost: Zero. Ok, MIG wire & shielding gas. With the flanges on the collectors I'll be able to easily try different collector lengths.

There isn't much more I plan to do to the dragster this winter. I'll probably go through the transmission myself (no experience necessary, I hope) and put a shift kit in it. It is supposed to be rebuilt so mainly I'll be checking. Gotta get a high stall converter. Rebuild and plumb the carbs and it should be ready for spring Test and Tune. I forgot the main change; the new short block is almost completely assembled and the head is done. Guessing it will be around 200-225 HP.

rainman, it will be interesting to see what the headers do to performance. That's what building stuff yourself instead of buying components is all about. I really appreciate your interest in my dragster thread. Thankyou.

 

[rainman]

I love it, when (and if) I ever find time, I plan on building one myself!!
So Thank You for sharing!!

BTW One question, do you know the firing order of that engine??
That will have an affect on the sound also!!

 

[ronnysplymouth]

If your running a Torqueflite it requires a kickdown for throttle pressure or it will burn up.......a manual valve body will cure this

 

[bob w]

I cut these power rings out of 3/8" flat stock today using hole saws.

ronnysplymouth, I've talked to some guys that simply wire the kickdown lever to wide open. By some method, I need to raise/control the shift points to 5,500 rpm.

 

[Dr Crankenstein]

Power rings? For exhaust tuning?

 

[6PACKRAT]

I've talked to some guys that simply wire the kickdown lever to wide open. By some method, I need to raise/control the shift points to 5,500 rpm.[/QUOTE]

Try this and it won't shift. Been there--done that. I know they cost a few $, but you won't be satisfied with anything less than a full manual valve body. Bite the bullet and BUY IT NEW --not at a swap meet or from a friends brother-in-law who has a real "deal" on one. Lokar kickdown cable kits really suck on a MOPAR. Try a Turbo Action Cheetah. Make a shifter. I made one for this set-up out of a screwdriver once. They are foolproof.

 

[Paul_J]

What type of hole saws are you using? I can never get that clean of a result using bi-metal saws in a drill press.

 

[sgtpontiac]

Quote..I've talked to some guys that simply wire the kickdown lever to wide open. By some method, I need to raise/control the shift points to 5,500 rpm.

Only problem is that it throws the line pressure sky high in all positions, reverse is normally high enough 80 to 120lbs....but that would add about 30 to 50 lbs of line pressure making it about 160 to 175 in reverse....forwards normally run about 35 to 50lbs...so it will be running about 80 to 120lbs all the time...shifts hard but plays hell on overrunning clutch, planetarys and bands when it's maxed out all the time....not to mention the clutch plates
I'd suggest you talk to a trans guy who is really up on the 904s and 727s and see if there is a way to modify the governor to raise the shift points other than having the kick down tied back....full throttle shifts at all speeds is annoying and hard on the trans......any of them that use that throttle type kickdown....

 

[sgtpontiac]

Thats my take on it.....

Power rings? For exhaust tuning?

I guess it would work??[S

 

[bob w]

Picked up the intake/header from Jerry the Sandblaster today. Cut the 3/8" thick metal rings shown above in half and welded them to the intake tubes at the plemum wall....

 

[bob w]

So there would be enough meat to radius the entry into the tubes from the plenum. Should give the air/fuel mixture a better path into the engine.

Thanks for the info regarding the transmission. Still undecided about how to go at that aspect. I've been getting a lot of technical help from Don Dolmetch, an old guy/mad scientist with a slant 6 powered dragster in Canada. He's been building Mopar drag engines for 40 years.

Regarding the hole saws; the larger is a Lenox and the smaller is a "no name". I start with light pressure until an initial groove is established by the hole saw. Also, I use lots of cutting oil and stop to clean out the chips if I notice cutting efficiency drops off.

 

[sgtpontiac]

Well that make a bit more sense....lol

I think we were thinking you were putting them into the exhaust tubes....[S
Yeah, I'm no mopar expert....GM....different story....I got out of the dealership stuff right before the 4L60's came out....glorified 700r4 so can't be too much different....other than the solenoid and V/Body.....