3.4DOHC Mains

[Lyle's GTP]

Hey guys, I was just wondering about the mains caps on our engines. They don't use the cross-bolt oil pan thing like the 3400's, do they? I was wondering if you could? I think it would increase the bottom end strength signifigently.

Lyle

[Lyle's GTP]

Nobody out there has anything to say to this?

Lyle

[Mitch DOHC]

u mean the windage tray...the thing that bolts across all of the bottems of the man caps.... if that is what u r talking about they do have them.

[brian89gp]

The aluminum oil pans have a different bolt pattern.

[Streetrodder83]

I believe these blocks already have splayed mains. Really, this would be my smallest concern in the strength of the bottom end.

[Lyle's GTP]

Could you educate me on the term, "splayed mains"? Which cars had an aluminum oil pan?

Lyle

[brian89gp]

Could you educate me on the term, "splayed mains"? Which cars had an aluminum oil pan?

Lyle

The aluminum oil pan is the 3x00 cross bolted one you asked about in the first post.

Our blocks do not have splayed mains, that is where the main bolts are at an angle (not perpendicular) in the block.

[Lyle's GTP]

That's what I thought. But the question is; could you adapt the mains/oil pan from the 3X00's to our engines?

Lyle

[Lyle's GTP]

Anybody have any info on this idea? Especially some of you experienced types.

Lyle

[3.4Z24]

I was looking at using the splayed maincaps from GM's aluminum bowtie block. You just need the center three caps and any competent performance machinist can 'fit' them. That's if they are the same journal size and everything. I haven't fully researched the idea, yet.

[SappySE107]

http://www.60degreev6.com/forum/viewtopic.php?t=1597

Check that, the same applies to us.

[Lyle's GTP]

Has anybody figured out if the 3400 mains and pan will bolt up to our engine?

Lyle

[Fierobsessed]

bump... Im trying to figure out the same thing lyle is. I don't really care if the oil pan doesnt fit. If the mains do, then I can put a serious main girdle on this engine. I have a crate 3.4 DOHC thats being modified for an Eaton M112 SC, custom intake, liquid to air intercooler, custom forged pistons, 4340 steel SBC SJ H beam rods, Total seal gapless rings. Im going to require some reinforcment on the bottom end, and 3400/3100 mains would make that easier to do, but do they fit? and who has a set they are willing to part with?

[GPXSS]

Yes.. the mains from a 3x00 will fit. Whenever you put new or diff main caps on any engine, they have to be machined so that they are tight in the grooves.

Now.. You also need to use the aluminum oil pan so that the crossbolts can go in. The bolt pattern is quite a bit different, but you can drill and tap the new holes. If you are doing this to a 3.4 Wbody, you wont have to worry about changing the mount. If this is on a 3.1 Wbody or a 3.4 Fiero, you will have to do some changes to the main front mount under the oilpan.. the old cradle style mount bracket doesnt fit. In this case, GM made a small plate that bolts to the oilpan itself, and the mount bolts to that.

Hope that helps, I think it can be done but it will take some machining and a little effort.