3.1 to 3X00 Head Swap Questions

[TazMan]

Okay so after some more searching I found a link from member v6h.o. that said the pushrod diameter is 5/16ths for all Gen III's. (http://60degreev6.com/showthread.php...=pushrod+width) I assume this would also apply for the Gen II's but someone please correct me if I'm wrong.

I also found a link from this same person telling someone he can get away with using his 3.1l pushrods for his 91 lumina top end swap. (http://60degreev6.com/showthread.php...ybrid+pushrods) Can I also get away with this without damaging my engine or experiencing any major loss in performance? If I must buy, then so be it, but money if very tight right now and if I could get away with not having to buy 12 pushrod it would be a BIG relief.

Again the Car is a 92 Grand Prix and the 3100 top end is from a 95 Buick Century.

[IsaacHayes]

The 3100 non-roller rockers are 1.6 ratio, as stated previously, that thread said they were 1.5.

Anywho, I figured out what v6h.o. was saying. You CAN use them only if you use the comp cam roller rockers.

But you CANNOT re-use them if you are doing a hybrid swap. That's what your are doing meaning, you are putting a whole stock gen3 head on there. It won't work with with EITHER the 94-95 3100 non-roller rockers, or the 96+ roller rockers. gen3 uses hydrualic roller lifters and therefore the geometry/length is changed for that. So you have to use a rocker arm that was designed for gen2 stuff (like the comp cam rollers) if you want to keep your gen2 pushrods.

[TazMan]

Contradicting pushrod lengths for hybrid

Oohhhh! Okay now I get it. Thanks so much. So I'm gonna have to bite the bullet and buy the pushrods. Now I just need to know if anyone can tell me about those different pushrod lengths. Here is the link again:

http://60degreev6.com/showthread.php...suring+pushrod

The lengths are at the bottom. Now if I am understanding this right, the differences are only 1/100 of an inch right? Can I just use one of the sizes listed in the post without any problems, and if so would I go bigger or smaller on an engine with 106,000 miles and heads with 76,000 miles? If I have to order the pushrod measurer then so be it, but I would much rather just be waiting for pushrods as opposed to waiting for a checker to get here, checking it, and then waiting for the pushrods.

[IsaacHayes]

I'm guessing all of those are close enough so I'd go for the one in the middle. I think Syn's numbers are inbetween what others have posted. I'm no expert though. What place are you goign to order from?

[TazMan]

I honestly have no idea. Any suggestions would be great though. I saw them at summit racing. http://store.summitracing.com/egnsea...115+4294869097 I was just looking at the post you sent me about www.pushrods.net. but I wasn't sure if you were asking or suggesting. I'm also still not sure about the tip style but I'm hoping they will be able to answer that for me.

[bszopi]

The hydraulic lifter should be able to make up for the 1/100th inch difference. So I would just pick one and go. I'm not sure if he posted about it on here or not, but do a search for pushrods and tejohnson as the author and see what comes up. Otherwise, go over to http://www.groomlakelabs.com and look in his gallery (phase 3 maybe?). Pretty sure he has all the info on the pushrods he ordered in there.

[TazMan]

Okay so I have almost everything I am going to need for my GP hybrid out of my Buick and I am faced with to minor issues. 1.) The power steering lines are rusted very badly and I can't seem to get them off. 2.) I am not sure what I am going to do about the Throttle body cables. First off, can anyone tell me if it may be possible to reuse my old hoses with the 3100 power steering pump? I don't mind buying a new hose if I must, but I am a little worried about having the same difficulty getting the hose off the GP to put the new one on. Now the throttle body; I haven't had much of a chance to examine them both thoroughly but it looks to me as if the GP has an extra cable for shifting the transmission. The buick throttle body didn't have such a cable provision. Does anyone know if the parts can be switched from one TB to the other for this cable and if not, what did other people here do about this?