What are we going to replace P4120534 with now that its dis-continued

I like the Rev N nator. My old Chrome box is my spare.

I like my Rev N ator too, but that's an entire system and not cheap. I have that in my Diplomat with the stroked 360.

Maybe the HiRev 7500? I bought one for my Power Wagon but haven't installed yet. Sounds good from what I read.

https://www.ebay.com/itm/JEGS-40805-HiRev-7500-0174-Ignition-Control-Unit/401591552120?

^ Internet picture.

R. Ehrenberg is a seller on ebay also if you would rather buy from him

That blue one looks reasonable for the money. Its all in the budget. Ehrenbergs price looks ok with free shpg.

https://www.ebay.com/itm/MOPAR-Hi-Po-ECU-Electronic-Ignition-Control-Box-B-Body-Charger-Satellite-GTX/323502461213?hash=item4b523fd11d:g:f7EAAOSwi0RXzdQB

I'd suggest a parts house or eBay 4 pinner (& a spare in the glove box).

I've run a Hi Rev 7500 on my Challenger for a couple of years now (about 15K miles). The car runs fine and I've had no issues with it.

Myself I've gone to GM HEI modules with the Ford TFI coil on the type of applications I used to use orange and chrome boxes on. Both the coil and the module together cost less than the Chrysler module alone, they wire right up to a Mopar distributor and produce a nice spark.

For the more performance oriented stuff, msd.

Not sure where you are pricing your stuff

Chrysler ICU - $13.88
GM ICU - $9.54
Ford TFI Coil - $8.66

Cheapest regular priced options at RA. Pretty sure I wouldn't use those options in any case, but the point it it's not really cheaper.

You price the high end and the GM/Ford combo is about twice the Mopar ICU cost.

Wells GM 4 pin module hidden in a 70s box gets it done lol

If I remember correctly, p4120534 was priced in the (ballpark) 80 range.

I'm quite familiar with these items as I ran them for decades and worked for the manufacturer who used to sell them.

For me, time for something different. For others maybe not.

Ok, didn't realize you were talking about buying MP stuff. Standard LX101 is under $40. Off brand equivalent is under $14, not sure I'd use that though or rhw later MP stuff for that matter.

the LX101 is a reasonable alternative but I don't consider it to be an absolute replacement for the chrome. I think the chrome is a better performance box. I use an FBO with the rev-limiter on one of my cars and like it, but it's a couple hundred bucks for the kit. my other car uses the LX101 without any issues.

I doubt most of the people running a chrome box actually need a chrome box. 7500rpm is a lot.

I'd suggest going to a yard & getting (2) OE 4 pin ECU's. OR (2) from a parts house (most are overseas made now), even the standard motor products LX101 (I believe). A high(er) dollar one might give more power but I ain't convinced but I cant say for sure. I like the HEI mounted under the dist on an alum plate (easy to make) or www.designed2drive.com has a nice alum tailor made one but it is pricey (dont forget the heat sink paste between it & the alum plate) & its a full 12V system so get an E coil or some full 12V coil. Dogdays had me get the furd TPI coil mentioned (yes dirt cheap from RA) & I put it on a DD truck with an OE HEI module & it was a new buildup then was sold quick all of a sudden so no actual before/actual exp but nothing jumped out at me about it but that setup is coming back to me in a trade so I will be trying it on something current. As I'm typing this I now remember that it did start instantly every time.

Right now, Rock Auto has a clearance sale on the Standard Motor Parts unit...$6.98 each.

^^^ (3) of em are $28.93 to my door. the LX101's are made in china now but I'd feel OK with 2 spares. All that is left is if they "pull" timing like some of the newer MP orange boxes reportedly do. All it is supposed to do (& nothing more) electronically is open the coil primary to collapse it when the dist pickup triggers it to do so & any electronic "delay" in that function pulls timing.

IMHO the reason any box "pulls" timing is that the engine speed is catching up with the transistor's speed. If you look at transistor catalogs you can see some interesting things.

R.