Rapom's Rocket - just another Duster build thread

[72bluNblu]

Thanks guys. Although the page views show plenty of interest it has pretty much just been me and the crickets... I thought there would be more questions?

Eh, sometimes it takes a few pages before people here start to notice. I know my Duster thread went the same way, I only had a comment or two besides mine until I was a good 3 or 4 pages in.

The work you're doing looks great, I like the triangulated 4 link. One of these days I may have to do that on at least one of my cars. Do you have all the dimensions and tube lengths?

 

[rapom65]

This suspension is based on FABO member MADDART's '67 Dart project. He put together his own components package based upon the design of RMS's Street Lynx system with mods and material upgrades to handle a twin turbo drag application. It is seriously stout, probably over kill for even a road race application. He sent me "the list" which I then modified (longer link bars to move axle back, ect). I can provide the components /where purchased to anyone who would like it. The Tri 4 link gets poo-pooed as a handling suspension on some of the cornering boards as there are better designs if you are really serious about competing. I decided on this route before I delved deep into handling theory but I'm still confident it will work just fine. I have approx $1k in the whole thing: $500 in the links/rod ends/bushings/plates/cross bar. Maybe another $50 in plate steel. The shock package was $386 thru Summit. The RideTech lower shock mounts and axle brackets $140ish thru Summit. $43 for Strange poly bushings if you don't want to run bearings.

 

[rapom65]

Next on the agenda is the installation of a hydraulic clutch. I have all the parts of a stock Z bar but I've always considered it a bit Rube Goldberg-ish (look it up on the web). After extensive research I settled on a master cylinder/pull slave system which, IMO, is the best option in a self fabricated hydraulic clutch setup. For a discussion of this reasoning and an exploration of the different systems folks have devised take a look at this thread:

Anyone running a hydraulic clutch with their 833? (

1 2 3 4 5 6

The best prices I found on the major components for my system was through Speedway. Pics of the master cylinder kit and pull slave cylinder. Most have settled on 7/8" bore sizes but others have had luck with 3/4". Just make sure the MC stroke and fluid volume matches the needs of the slave cylinder or you will either under stroke (not enough clutch movement) or over stroke (without a pedal stop to limit travel you will blow the seals out of the slave).

 

[rapom65]

As part of the transmission hump conversion I swapped out the auto pedal assy for a clutch pedal assy which I had first cleaned, painted, lubed, and added new shaft bushings and foot pads to. Before ordering anything an examination of the engine and interior sides of the firewall, to find a suitable location for mounting the master cylinder, identified the following issues: parking brake assy, cable and mounting bracket on the interior. Brake booster, booster support bracket and a big enough flat spot in the sheet metal on the engine side. There seems to be a fair amount of differences over the years in the A body pertaining to the location of the parking brake and stiffing ridges formed in the sheet metal. Some have no problems and others, like me, a lot to deal with. Only one spot on the fire wall had a flat spot big enough for the MC mount pad and that was right at the top of the hole for the parking brake cable pass thru. All the issues above looked like they were going to be in play.

 

[rapom65]

During my research I had looked at quite a few hydraulic clutch setups but they were all used in conjunction with manual brakes. Being me I had to be different and have power brakes. Getting this to work with a booster in the way was going to be uncharted territory. Because the MC has to be offset from the clutch pedal a link needed to be fabricated to connect the MC push rod to the clutch pedal. This link has to intersect the pedal no more than 2" below the pivot point of the pedal. This has been shown to be the sweet spot for proper geometry and full stroke of the MC. Some preliminary measurements and a few educated guesses latter it looked like the parking brake mechanism and bracketry would just clear my selected MC mounting point and that the push rod would be right at the magic 2" point. Yeah, I got lucky... I made a paper template of the mounting pad of the MC and used it to mark the fire wall for the best fit and the 1.5" hole saw to come. After the center hole was cut I stuck the MC in place to verify everything would clear before drilling the holes for the two mounting bolts.

 

[rapom65]

A backing plate needs to be incorporated into the design because the sheet metal of the fire wall is not strong enough to take the flexing forces of the MC for very long before cracking sets in. I decided to permanently attach my plate to the pedal box and turn the mounting bolts into studs to make assembly easier. Because I didn't have any 1/8" plate I had to sandwich some sheet metal together thus the strange spot welds.

 

[H20loo]

Rapon- there are a lot of us that follow threads like this and it makes us feel like students- watch and learn! Keep up the good work! I wish I had time, like in the old days for me, that guys would drop by my shop or we would go out and see what some other shop was doing after hours. Now we drop in through your pictures and we lose the social side.
I really need a beer to go with all this chat>

 

[rapom65]

I agree whole heartily. FABO and the "Corners are best" forum on Moparts have become my social outlet since moving 4 years ago. My thread subscription list is two pages long! I left behind my two car buds, and we stay in touch, but we don't get together to work on each others cars anymore due to the distance. We've been regulars at MATS for 6 years running but this year I'm out due to FINALLY starting a new job. I enjoy documenting what I do and sharing it with others. While I love the high dollar builds it's just not me. I like to figure out how things work, how to modify it for better performance and then build it in my shop. You can get awesome results with some forethought on parts combos, thinking outside the box and then making it yourself. I hope I'm helping the guys strapped for cash see how it can be done cheaply and on their own. All it takes is a commitment of time. It does not require a huge investment in tools either. Besides basic hand tools my fab equipment consist of a 110 volt MIG welder, a Harbor Freight drill press, a 4.5" grinder and a now busted 14" chop saw for bigger metal cutting.

I'll second the beer(s)! :drinkers:

 

[rapom65]

MC bolted into place.

 

[rapom65]

This pic shows the 2" (between arrows) I was talking about. I doesn't have to be exact but I wouldn't stray too far away from that distance. Normally it will fall in the center of the square that is formed by the 4 spot welds that join the clutch pedal to the linkage arm.

I rummaged through my nut and bolt box and found a full length threaded bolt and a couple of long nuts that I tacked together to make a bushing. Along with the heim bearing and a couple of washers this makes up the stand off. I did recess the hole with a small hole saw because the bushing wouldn't sit flush on the pedal which cocked the whole thing off alignment. Thought it was quicker than trying to cut the bushing on the correct angle. Easy peasy.

I left the linkage/return spring bracket attached so I have the Z bar set up available just in case this idea doesn't pan out. If the hyd does work I'll cut it off the pedal at a later date.

 

[rapom65]

Bolting the booster back on showed that my calculations were off a smidge. The band clamp and bleed nipple are hella close but it doesn't touch.

 

[rapom65]

The stock booster had two support brackets, a horizontal one to the inner fender top and a long vertical one to the bottom of the fire wall. Since I removed both the booster would wiggle just enough to rub on the MC bleed nipple. I took the lower support bracket, cut it in half, and bent it up in my vice to form two new brackets which lock the booster down like it was welded in place. A spare fender bolt, a nut welded to the underside of the bracket and a hole drilled through the pinch weld at the top of the fire wall complete securing the top bracket. The stock fender brace bolt attaches the lower bracket. Problem solved with zero cost and a little ingenuity.

After the clutch is bled and everything is working I'll replace the bleed nipple with a plug cuz I just don't like the way it looks. Yes I'm anal...

 

[rapom65]

The US Brake MC kit I used for the clutch came with two sizes of reservoirs which can sit directly on top of the MC or on a remote mount and cap arrangement. Due to the booster hogging space again my only option was to use the remote mount. I wanted to attach it to the fire wall but there really wasn't a suitable spot. So plan B was put into action and a bracket was made to attach the remote mount to two of the brake MC studs protruding from the booster. That completed the MC side of the clutch set up. The slave cylinder fab will have to wait until the engine and trans are reinstalled. Although not 100% satisfied with this arrangement it was good enough to continue on with the next area of attention which is circled in red on the last pic.

 

[rapom65]

Went out to the shop today to get a interior side shot of the clutch linkage before we move on to another area. I need to come up with a little bracket or brace to lock the brake cable in place as the sleeve moves around with the cable when setting and releasing the parking brake .

View attachment IMG_2294.JPG

 

[rapom65]

Just wanted to give you all an idea of the stance. I set the wheels at the ride height I built the suspension to. I'm guessing it will sit maybe an inch lower when the full weight is on the springs and everything is adjusted.

 

[/6 Matt]

I'm digging this build! You got some mad fab skills.:glasses7:

 

[rapom65]

Thanks Matt, glad your digging it. Skills? I don't know about that but MAD??? Absolutely!

 

[rapom65]

I don't know how deep I want to get into explaining the planned electrical system changes. Some times these things get so complicated that it's hard to document and even harder to follow. Maybe I'll list the mods and then do a little blurb on each and then see if there is interest for a deeper dive into any.

Plans:
Eliminate side marker lights
Eliminate fender top turn signal indicators
Eliminate "Fuel Pacer" system
Disable "Seat belt interlock" system and remove as much as possible
Replace stock ignition with HEI
Rewire car for trunk mounted battery and cut off switch
Eliminate redundant wiring where applicable
Bypass ammeter and install volt gauge

The marker lights were easy. Unplug and remove the marker lights at all four corners. Make filler panels out of same gauge metal (my old trunk lid lives again!) and weld in. Use appropriate techniques to NOT warp your fenders/quarters, grind smooth & finish during body work. I left the wiring in the rear wiring harness alone.

The "Fuel Pacer" was an option in '74 and later cars. It was a vacuum operated switch that turned on the driver's side fender top turn signal indicator (indicators were another option). A high vacuum signal would turn on the light...the idea was keep the light off (ie."your foot out of the throttle") = low vacuum = light out. An over reaction to the "Gas Crunch" era.

Another great idea was the Seat Belt Interlock which was a system that killed the ignition if the front seat belts weren't fastened. Government "Safety Nazis" at work. A means to bypass it was quickly devised.

This thread will explain all the above: Need help identifying these please

 

[adiffrentcity]

Snowflake wheels look pretty good on there! I've been eyeing a set here in TN but wondered how they look on a later a body. I know now! Keep up the great work, as was said before a lot of us are more comfortable lurking and just enjoying the pics and your progress. Rest assured we are paying attention.

 

[rapom65]

I actually borrowed that wheel off my '65 Barracuda for the pic as it was the widest thing I had access to in a 15". Those are 15 x 10 Centerline Auto Drags in back and the two white boxes by the front bumper have two new 15 x 7 Auto Drag copies in them. Because of the dearth of performance tires in 15" sizes I will eventually step up to 17s, 18s or 19s. Right now I'm torn between wearing out the supply of 15" tires I have on hand or spend the $ on modern wheels from the get go.

 

[rapom65]

Damned if I didn't have bad luck I'd have no luck at all! Haven't had so much as a sniffle the last couple of years and now on my 3rd day at my new job and I'm sicker than a dog. Had to take the day off... what a way to start. May be a few days before I post again, got to go to bed and rest up. Later.

 

[rapom65]

Sorry for the delay in updating the thread. Been working at a new job and fighting some kind of virus all week so my web time has been severely limited. Yeah I know... Boo-Hoo crybaby.

Let's get on with it... The next thing on the list was changing over to a HEI ignition system from the stock ballast/ignition. Why you ask? Mainly because all my current equipment was quite old and needed to be replaced/upgraded, the engine compartment wiring harness was in sad shape and the generally happy results posted on several member's HEI threads. I consider myself a semi-purist, ie. I believe a Mopar power train should be in a Mopar chassis, Ferd in Ferd, Shovey in Shovey, ect. however I have no issue with mixing and matching other things to achieve a better result, especially if it can be done at a lower cost, over using stock parts. Flame on... your wasting your breath, or, finger tips in this case.

The stock distributor went with the motor donated to my friend's son's project so while perusing the swap meet at MATS I bought a really nice core electronic distributor with the idea of doing a rebuild/recurve for the car. Walking through the vendor isles later that day I came upon the Mancini booth and they had brought with them a handful of brand new distributors, built with all the good parts and a performance curve, for $100 bucks. A C note lighter in the wallet but one less project ahead... well worth it.

The rest of the ignition I had on hand was a questionable stock ballast resistor and a very old but serviceable Orange Box ignition. The coil was missing and most of the harness wires were brittle and cracked at the engine connections where the heat, oil and gas had taken their toll. Wow, lots of little things to fix and replace. That prompted the search for an ignition upgrade. I've had MSD stuff before and while not cheap that was were I was headed until I started reading about the HEI guys were trying out. Many were getting their components out of junk yards for super cheap, right up my ally. After a trip to the local self help yards I had no luck in finding good serviceable parts. They were in sad shape or pulled along with the engine. New parts were purchased thru Summit and Rock Auto for reasonable cost so all was good in the end. I cut the tatty wire wrap off the engine harness and proceeded to strip out the wires for the following: L & R marker lights, L & R fender top indicators, the funky "Fuel Pacer" components & wiring, the seat belt interlock relay (yellow leads spliced), the coil and distributor wires, the altenator wire to the bulkhead and the remaining wiring for the ballast resistor and ignition box. All this was not needed or was going to be replaced/rerouted in the HEI conversion and rewire for the trunk mount battery. I do not recommend the average "Joe" try this without adequate knowledge and ability to trace wiring using schematics in the Factory Service Manuals (FSM's). You could easily leave all this wiring in place, just disconnect and tape/terminate the ends properly. I printed out the complete wiring diagram for the car, taped it together, then spent hours and hours tracing wiring. This was a lot to take on at one time and I have an extensive aircraft maintenance background. Hopefully it works!!

Here are the parts and info for my ignition:
"E" core coil and heat sink mounting bracket, Summit PN ALL81230
Standard Motor Products Ignition Control Module, Rock Auto PN LX301
ACDelco Ignition Control Module Heat Sink, Rock Auto PN 10474510

View attachment IMG_2214.jpg

 

[rapom65]

And all put together into one little package. Sorry for the blurry photos, my camera doesn't take great closeups and is sensitive to movement during close shots, plus I just plain suck at photography.

I made a little bracket with a 90* bend to mount the heat sink/module to the back of the coil. The finned silver heat sink is for the HEI module which gets really hot and needs a way to keep cool or it will fry very quickly. There are lots of ways to do this from directly mounting it to firewall, inner fender, using the ACDelco heat sink made for that purpose or even computer heat sinks. Just don't forget the heat transfer paste that comes with the module. That little black module is equivalent to a factory ignition box and puts out a very healthy spark. Two leads go to the coil +/-, and the other two go to the distributor. I used the factory distributor wires I stripped out of my engine harness, shortened them up and crimped/soldered on female Packard 56 spade connectors and covers harvested from some scrap harnesses I keep around for such occasions. The black connector with the yellow, blue, red and black wires is to a relay to power the module. I took the power directly off the starter relay power stud with a 10 gauge wire as the module needs a steady 14 volts to work properly. That is just how I did it, there are many ways to accomplish the same thing. This is where the wiring mods start to get complicated to document and follow as I changed so much at one time. Try to follow the best you can.

I'm mounting the coil/module/relay on the flat of the firewall next to the windshield wiper motor (red circle). The white arrow is pointing to the relay which I conveniently covered with the red circle . This is close to the distributor and existing wire harness for routing purposes, is out of the way and may be a good spot for airflow for cooling too.

The last pic is the best HEI wiring schematic I've ever seen. I don't know who to give credit to as I copied it a long time ago during my research, but whoever you are cudos for a professional job! The only thing I would add to this is a ground wire from the B-C side mounting screw to ensure the module is grounded to a very good source.

 

[rapom65]

Wire connections left to right routed under coil:
Yellow = power lead from relay (87) to coil +
Dark Brown = power lead from coil + to module pin B
Black/Yellow tracer = ground lead from coil - to module pin C
Light Brown = tachometer lead from coil -

 

[rapom65]

As you may remember I was not entirely happy with my clutch reservior mounting solution. It seemed to me it would be prone to trapping air in the line and difficult to bleed since I couldn't find a spot to mount it higher on the firewall. Deleting the ballast resistor and orange box opened up a much better spot to mount the reservior so it was repositioned there. Now the reservior is the high point in the system and the oil line does not have the big curving dip in it like before. I may have to do a relief to the underside bracing of the hood for reservior clearance but that is no big deal.