Dauntless Dizzy And Fi Project Vs Gm Hei Question

Looking at options for our new to us 71 cj5 renII.
It's all stock now with CA smog . I just got through an ordering fiasco for tune-up parts for a prestolite (from 2 part stores and 3 online vendors). I decided to check options.
I see there is a drop in extended distributor available from DUI p/n DUI-63720-EXT found under their amc listing in a pulldown<-Click. Appears that the shaft is extended so manifold grinding is n/a.
Howell efi has a kit for tbi that seems may work. Howell tbi HB225 Kit <-Click
If I do this swap all the factory stuff will be removed, cleaned and stored properly.
Removing the air pump will provide room for the extended dist. I assume the hei dist will trigger the howell tbi events (from reading other threads here).
Now to revert. Will a gm hei dist "fit with manifold grinding under the stock air pump?

 

Here are some pics that I hope shows what I'm dealing with. driver side - pass side - top
dindt think bottom would show anything helpful

 

Can someone that has a 66-71 225 delco oddfire dist measure the overall height and diameter of the dist and post it here?
I'd like to explore the option of using this dist with the pertronix.
The height dimension should be from the top of dist cap (less wire lead terminals) to the top surface of the base. With this I can check overall installed height and diameter for clearance.
I can only assume the pertronix was used in CA (other states?) to clear the smog pump.
More and more that looks to need to be shed.
Option is to stock up on tune-up components for the prestolite.

 

I'm useing a DUI distributor with the extended shaft. I didn't need to grind the intake but I did replace the regular hex head bolt with a button head bolt.

 

I don't understand why you would want to retain the air pump. Your 1971 is CA smog exempt. Ditch that pump and increase your options. I run HEI and highly recommend it.

 

The jeep is essentially factory complete renegade II save for consumables. Intent is to get it running and then decide options. If pertronix made a kit for the prestolite I would not be exploring options. Right now, I have everything to do a tune up (except spark plugs to be sourced locally) using all factory components.
I *may* opt to remove, clean and box up all the emission stuff for posterity. I had not laid eyes on a complete early emission jeep for many years. Two of my 3 early emission vehicles (68, 70 1nd 71) retain all the factory components, shields, solenoids, lines, etc. Part of the decision to purchase these vehicles was their originality.

 

I'm using the older DUI dist and a Powerjection FI. My only advice for you would be do the dist. first and get it running well, then do the FI. I did them both at the same tie and it drove me crazy troubleshooting the system after.

 

JMO - These engines also used the Delco points distributor, for which parts are widely available (see 1964 Buick Special 225). If I had to keep the air pump, I would abandon the HEI idea and use a Delco points distributor to trigger a MSD module. This will give you at least as strong a spark as the hot coil in the HEI cap, and allow you to use the original cap and wires. The points (or the Pertronix) will trigger the MSD module just as well as a magnetic trigger, and the points will last a loooong time when relieved of switching the coil. No other changes are needed, since the Howell EFI is not controlling spark. You'll have the same (uneven) tach signal as the factory engine, and that should work fine for the Howell EFI (check with Howell).

There is also a short cap for a 6-cyl GM HEI distributor, for the 1977 K5 Blazer with the 250 engine. I have not tried it, but this cap should fit on the odd-fire HEI distributor. The internal wiring is a little different, since the coil must be outside the cap, but it should not be difficult to modify to this end. You could even buy the complete 225 even-fire distributor and modify it to work with odd-fire, as has been covered here and on other sites. This would help you with height, but not diameter. More Information for STANDARD MOTOR PRODUCTS DR446

 

not to change your mind . I still can get points and condenser , rotor , cap from oreilly's for the prestolite
but parts are there brand . you just have to look at computer at store or they will try and sell you delco points

 

I have a Pertronix setup in a Delco distributor, it's in a box because I just moved but I can try and dig it up and take a measurement. I'd even be willing to sell the unit to you. As for the Howell FI kit, my friend has one on his Chevy 350 in his CJ7 and it's awesome. Runs like it was from the factory. There seems to be some confusion on this site whenever FI conversations start up. TBI kits are really just glorified carburetors. They use sensor inputs to measure how much fuel to dispense. The engine load measurement is taken primarily from the TPS (throttle position sensor) not the engine RPM's. I installed the Holley kit on my 225 and it was just a static map of how much fuel does it deliver at any given voltage from the TPS, it didn't really take RPM's into account at all. There is no spark control in a TBI kit so your distributor doesn't matter as long as your Jeep is running well. I second what Posimoto said, get it running well first. Then all you are doing is changing the fuel delivery system. Pretty simple! Warloch is great at TBI kits on these V6's.

 

X2 on just leave the points and get it running as well as can be done with points. Then make a plan on what you want to do.

 

FIFY.

Actually, I think any kind of TBI does keep track of engine RPM via the tach signal (ignition coil negative terminal), or by a more fancy (and accurate) way like a toothed wheel on the crank. On an even fire engine, that's enough information to control spark advance as well as meter fuel. Howell chooses not to control spark, instead only controlling fuel. With an odd-fire engine, the uneven spark interval makes spark control more difficult. You would need a circuit that adjusts the trigger time synchronous with the firing order. Neither the GM ECU (used by Howell) nor the Megasquirt can do this without some added circuitry.

 

I'm not sure how to message you. I'm interested and also would like to know the dia and height of the dist.
I like this option as the delco was originally installed on a Dauntless and the pertronix will give me reliability. idk why (CA smog, year thing, amc?) Prestolites were installed on some Dauntless
I have converted two other point driven vehicles to the pertronix. Both were done years ago and have given me no issues.
twin2- I went through that exact excercise at Oreillys and Napa before I realized I had a prestolite (actually took a pic of the tag completely buried under the dist and air pump. had to use a point and shoot with supermacro enabled.
Daryl - moving in that direction

 

I think we're saying the same thing differently. Monitoring engine RPM's via a tach signal is not spark control. All the TBI systems I am familiar with just take a reading from the distributor in order to tell the computer if its on the idle map, or high RPM map. In my mind, spark control can advance timing etc. TBI systems don't do that on even or odd firing motors.

 

The GM model 1227747 ECM typically used for tbi and the model that Howell uses in the their Jeep application most definitely controls spark and timing in EVEN fire applications. You are correct with regard to ODD fire applications where it incapable of controlling spark and timing. This ECM was used in 1987 to 1991 C/K Truck, Van, 4.3L, 5.7L, 5.0L & 7.4L engines.