magnum swap questions

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turboking15

turboking15

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I am putting together a 5.9 magnum that i will be swapping into my 87 conquest and have a couple of questions that i havent been able to find the answers to.

Some info: It will be carb'd, electric fuel pump, programable msd with magnum dizzy, and i will be doing the whole wiring harness from scratch. Already have an la timing cover and water pump.

First: is there a way to wire the magnum alternator to be used similar to a 1 wire setup? I have seen similar things done on the newer gm alternators where you jumper a few wires on the plug together and it is self exciting with no reg needed.

Second: If that can be done can i use a magnum water pump pulley on the la pump and run a serpentine belt with a heims tensioner on the alternator? The car will not have a/c or p/s. Also using the magnum balancer with integrated pulley.

Third: I have seen mention of this elsewhere, but figured id ask anyway. I am using an ax15 5 spd trans and a 5.2 neutral balance flywheel. I have already cut the tone ring off the mag flexplate in an attempt to sandwich it between the crank and flywheel. Does anybody see any issues with the spacing of the clutch disc on the input or any other issues? I understand there are flywheels out there that wont need this or i can drill the flywheel but like i said i have heard mention of this method being used and would like to here some discussion on it.

That should be it, keep in mind this is a very budget oriented build and i have way more time than money so trying to do this with what i have or can get cheap.

Thanks
 
IF it's carb'd, why dick with the tone ring and all that? Just run a small block distributor and MSD and be done with it. I'd only sweat the tone ring if you're going FI and need crank position sensing.

Also, why not run the full serpentine belt setup? Without the A/C or power steering, it's as compact as the LA stuff, and way more reliable. Automatic tensioner? Heck yes. The Magnum alternator hooks up identically to an A-body alternator, so similar mods would work, but the factory regulator circuit is so simple, I wouldn't be afraid of it.
 
And remember, the 5.9 is not balanced same as a 360. I have the diameter and depth of the holes written down somewhere, and they're clocked identically to 360, but are smaller.
 
no you can not run a 2 wire alternator same as a GM unit; they need to be externally regulated, stock the computer controls the (in magnum engine) but stock 2 wire voltage regulator will work fine
 
Im not worried about the tone ring, i cut it off the flexplate so i could snadwhich it between the neutral flywheel and crank, im just not sure if thats possible.

If you could post up the drill diagrams that would be amazing.
 
If I'm understanding this correctly, you want to essentially bolt a flexplate *and* a flywheel to the crank flange? I would guess that's not a good idea...can't you just get a correctly balanced manual flywheel for your 5.9?
 
txstang84 said:
If I'm understanding this correctly, you want to essentially bolt a flexplate *and* a flywheel to the crank flange? I would guess that's not a good idea...can't you just get a correctly balanced manual flywheel for your 5.9?
Click to expand...

There is a guy who claims to have done it that way and i wanted to see if anyone else had done it that way, if not ill rebalance the neutral fw i have now.
 
Pentastarnut said:
pics of motor in car, front frame section, and are you on SQC ?
Click to expand...

Havent dropped the motor in the car yet, still putting it together, just trying to address all the questions i have. And yes im on SQC, same user name.

Ive looked through every bit of olive and flatblack87's swap threads for info.
Flatblack87 is actually the one who claimed the sandwhiched flexplate would work but never verified.
 
thought i recognized your name, i am Olive8, let me know if you have any questions ;) it's been a fun build. i'm tearing it apart right now for paint/rebuild.
 
bringing this back, i finally have the motor in the car and running now i need to mount and wire the alternator. Does anybody have a diagram as to how i would wire the new alternator into an old style regulator and the rest of the system? btw the battery is in the trunk and i have 2g wire going from the alternator to the battery.
 
I think it was UOP that did this very swap.
 
Sounds, like a wicked swap. Had firsthand experience In a 88 TSI,these cars HANDLE. Subscribed.
 
Uop did it in a 3rd gen rx7, but same general idea. Got the alternator wiring figured out so it now runs the 136 amp bosch alternator with old style regulator. Measures 14.65 volts at alternator and 14.55 at the battery! Hoping to have the car running and driving soon just waiting on a driveshaft and we are finishing welding up the cage.

Here is a rundown on the setup:
01 5.9 mag, new bearings, rings, gaskets. Stone honed cylinders cleaned up deck surfaces
Home ported magnum heads, ls6 valve springs and retainers @1.7 ih, crane rocker stud conversion, 1.5 aluminum Chevy rockers, jomar stud girdles, 7.2" hardened pushrods, arp head bolts, 1121g head gaskets, oregon cam regrind 304/306 242/[email protected] .555/.556 110lsa, mopar m1 intake gasket matched and plenum cleaned up, 750hp holley, electric water pump, walbro 255hp440 with mallory 4307m reg, billet dist with msd programable 6 box, hand made 1-3/4" primary 3" collector headers, exhaust mounted crank evac, aem widebands, 16" collector extensions.

Also have a single stage of nitrous once i get the rest of the car sorted out.

If you have anymore questions feel free to ask, my goal with this car is to see just how far a stock magnum can be pushed and how fast i can get one down the 1320.
 
A well thought out combination. The kicker is that first turn after the quarter. Good luck.
 
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