Crankshaft question

[VyperFox]

Hate to revive an old thread, so I thought I'd just make a new one.

Seeing how the 4g63, being either 6bolt or 7bolt, are identically the same block(to my knowing), if I have currently a 7 bolt, can't I just rebuild the block, drop in a 6bolt crank and 6bolt internals. Can I call it a 6bolt engine? Or is not possible? Being since there's a subtle difference between blocks?


Thanks in advance

 

[gorf]

won't fit don't know the details but they are different. The way they are held in place (journals) are even different, the 7 bolt has a saddle arrangement and the six bolt has journals caps.

 

[pauleyman]

are identically the same block(to my knowing)

Nope.

 

[jconcepcion4g63]

The main and rod journals on the crank and the main bores in the block are different. This is second hand knowledge to me so I could be wrong tho, I have never mic'd them to see for myself.

Why do you ask? If you do not mind sharing? have 6 bolt parts layin around trying to save some money or something?

 

[VyperFox]

Sure I don't mind sharing. No, not to save money. Seeing as how I'll be tearing down this dsm to the last bolt, and going overwith it, since it's been pissing me off for years, only ### it doesn't want to run correctly not matter what kind of repairs or fixes I do to it.

So with that being said, might as well rebuild the and turbo it while it out right. But I also read other posts out there, stating that a 6bolt is better than a 7bolt. Was planning just to use my current 7 bolt block, and dropping a 6bolt crank and 6 bolt internals, instead of buying either, the bare 6bolt block, or a complete used 6bolt engine and just rebuild that, with forged internals. So all in all I'll be attempting, a non turbo to turbo conversion with my dsm, all in an attempt to get rid it's phantom illness that I can't seem to find. But I'm also ruling out my options before I start this project, and I got a 5gallon drum of Chem that would like to see some action . Just need to get a decent welder and Ill be set, tool wise. I'll also be trying to hit atleast 200-400 whp while I do this mod. This dsm is just way too slow, kind sad when a moped can zoom right by you and you can't catch up. It's just that slow on speed and acceleration.

Any advice will be helpful

 

[force_feed]

You can make your 7 bolt motor just as powerful as a 6 bolt motor. The only "problem" with the 7 bolt is crank walk, and that is caused by excessive thrust bearing play (1000 AAQ - Terms).