OLDS Dx build

[olds307 and 403]

The blocks are cheap because of how horrible of diesel motors they were. Using 4 torque to yield cylinder head bolts is suicide on a 22.5 to 1 diesel motor along with no water/fuel seperator, all for the performance of an Olds 260. The 4.3 V6 is still a turd but the extra head bolt per cylinder much improved head gasket issues. Supposedly the FWD aluminum heads had issues with them. Add on too short of main cap bolts and have a motor to destroy the diesel car market for years.

 

[Nitro442]

Until this thread, I'd never knew the DX (diesel) block is preferred for anything. I know that engine platform can accurately be described as non-preferred. But these blocks appear to have a very large bore spacing that is made up with ALOT of material. So is it safe to infer that these are very very very stable bores? I'll answer/guess yes.

What is the deck height? Bore and stroke? Are these 5 main blocks? Are there any stock dimensional forged rotating assemblies or crank options available through the aftermarket? What heads fit them (aluminum)?

The reason for the questions is that a big bore spaced block is what is found in the aftermarket for blocks, i.e Dart, Brodix, etc. I do understand about increasing the cubes with a 425 crank, but a lower rod to stroke ratio is much easier to make more power with in a non NA build. And by easier, I'm implying cheaper. This is becoming more and more prevalant in the world of boost and boosted x275 cars.

Just curious and interested as these blocks, despite not being readily available, are relatively inexpensive when found/available.

Last time I was at one of the yards off I-25 near Colorado National Speedway there were 2 or 3 Olds 350 Diesels in there! The only thing that keeps me from building one is not the cost of acquiring the core but the machine work and parts and up until now finding a 425 crank (The 330 crank with spacers works but then you're leaving a lot of Cubes on the table). IMHO There's no point in doing a DX build for anything other than Big CI and an all out build. I'd say you're probably looking at $10K in parts and Machine Work unless you get really creative or have parts laying around. The cost is probably the biggest reason you don't see DX builds often, you can build a decent SBO 350 for 1/2 the money (but probably 1/2 the power too LOL).

unfortunetly I don’t have any other blocks laying around...but I’m up for being different and I like my olds... I see lots of guys with ls motors... that won’t be me...I’m up for building a big cuBe sbo.

 

[fleming442]

Check your lifter bores. I thought some were .921? .842s and you're golden.

 

[Nitro442]

Check your lifter bores. I thought some were .921? .842s and you're golden.

The dx blocks I have are .921 lifter bores. The d block I have is .842 lifter bore. But the mains in the dx block are almost a half inch deeper than the d block

 

[303'505rollin]

I go/ used to go alot to that pull yard but after the old man died his son hits you hard for everything but if you go up the road to Elliott's he's way more reasonable and still has/knows to keep the old stuff

 

[rogue_ryder]

I go/ used to go alot to that pull yard but after the old man died his son hits you hard for everything but if you go up the road to Elliott's he's way more reasonable and still has/knows to keep the old stuff

Yeah Speedway is the place I went to and he did charge way too much but he had the brackets I needed. I'll try Elliotts up the road next time I'm on the hunt for used stuff!

 

[303'505rollin]

Idk where you're located but on 85 between Ft lupton and Brighton on the right hand side going south there is 7sons(sevensons) they have 88 and older too, there entrance is small but the yard is big it drops from sight when driving by bye so it's hard to tell if it's there

 

[64nailhead]

Less cubes+more beef=high revs+more boost

Usually an easier balance job as well. By easier I'm implying cheaper lol.

 

[303'505rollin]

At speedway there is a diesel cutlass way in the back near the 50s cars it's dark blue buy a dead tree it's all there motor wise, shoot I think there's even 3 complete wagons not touched on that side. I haven't been there since may but much doesn't change there. I'll be back in CO in a few weeks I'll do a walk thru if I can depending on weather I'm down in NM right now