So about a year ago I decided to try the Dynamod HEI module that came with my DUI distributor. The Delco one that was in there was doing ok. But I read an article that said the some aftermarket "performance" ones were worth a little power at higher RPM. Didn't really notice anything (Yeah, I know...why was I not surprised?... lol). So I just left it in. Last few drives I started noticing power starting to fall off above ~4000 rpm. I knew the fueling was always right on the money, so I started back tracking what the latest things I did and realized the HEI module. Put the Delco one back in and voila... power came right back. Even the start up is snappier (guess it was degrading). I use this Arctic Silver thermal compound under the module and it was still nice and fluid, so I know the heat transfer is good. Must just be the same-ol' same ol' with these unreliable aftermarket stuff. Guess I'm glad it didn't fail outright and leave me stranded.
The old Delco stuff pretty good , if used correctly . Mine has been going good 20 years , never let me down.
This may sound goofy, but I've always trusted Accel for this part along with Accel HEI coils to work together. Best that I know of since modules are directly affected by heat....no way to really test those things
This reminds me... to put a new one in the glove box. I've been running the Skip White distributor since 2012, whatever module they use is what's in there. It seems fine, but you just never know.
That's odd. My first DUI distributor with their module ran in my small and big blocks for 10 years, and was not babied. The second owner has had it for almost 15 years, daily driven, never touched. My current DUI is going on 3 years now. I dont put on lots of miles anymore, but the ones I do are hard. This may sound naive of me, but DUI stuff has always seemed a cut above the garden variety aftermarket stuff. Not saying they can't fail, but I think they deserve better than to be written off in the same category as the cheap stuff.
O'Reilly's Has a tester in my area. They checked out my module in my 92 GMC Van. It gets hot. Burned the guys hand when he did the check.
That's how they test them sometimes, try to make them fail when hot. And for fun they'll hand it back to you and laugh when you yelp. I redid the ignition in my old pickup several years ago, figured 250k miles and 25 years with no changes, it was due. Autozone module left me on the road in two years. Put a BWD module in it from Advance, still going (knock on wood.) I notice on the 4th gens the module is on a big heat sink mounted on the head, might be worthwhile to relocate one like that?
Could be the outlier in this case, and you got the bad one, it happens to the best of them once in a while, and DUI does make some good stuff, and is a top quality company.
For the simplicity and functionality of a good HEI, hard to beat a full DUI setup. If you have an HEI to start, it's a no brainer. Starting from scratch, then the MSD's "good stuff" or the DUI's will do one well, pending on your needs. The MSD "street Fire" stuff, and some of there components are not what they used to be.