so i ended up getting a 3100 for the swap instead of the 3400. i know the bore is diferent 3100 has 89mm 3400 has 92mm. what else is diferent? its not to late for me to get a 34 because i got the 31 for free, so no loss. but i know they are considered the same motor, but the main question is is it reasonable to bore the 31 to the 34 spec. i know 3mm is ALOT but if they are the same block only one is just bigger, and the heads are the same... it could work... i dunno just a thought... also what about the TwinDualCam 3400? would that fit into the j using the same mounts and @!#$ as the pushrod 34?
Also note: if it is a 99 or older 3100 you can put the 3400 or newer 00+ 3100 top end on it, and get the same power output as the newer 3100's do.
good to know. what about the 3.4 from the cutlass supreme tho? i can get a complete running donor for <1000. would that engine bolt in the same as the 3100 and 3400, or would it be diferent?
3100 and 3400 share the same mounting points... well, the 3400 requires minor modification due to a pulley boss being in the way.
Before:
After:
This pulley boss needs to be hit with a grinder:
Also you will need to use one of the smooth pulleys on the tensioner to replace the grooved one
Edited 1 time(s). Last edited Thursday, August 14, 2008 10:09 PM
so the 3.4 would have the same mounting points as 3400 and 3100? like i said i can get a complete running cutlass supreme for less than 1k so that might be nice (starting with 210hp as opposed to 175hp)
Kardain wrote:This pulley boss needs to be hit with a grinder:
That must have something to do with your mounting scheme? I use the pulley that's on that boss. It's how I can route the belt without a/c.
can someone answer this ? 4 me please? does the 3.4 have the same mounting as the 3400? and with it being taller would it fit in the cav? please help.
SHOoff (Tuner Bash Beer God) wrote:Kardain wrote:This pulley boss needs to be hit with a grinder:
That must have something to do with your mounting scheme? I use the pulley that's on that boss. It's how I can route the belt without a/c.
It would seem that of the 3k pics or so I have during the swap, the 3.1 bracket is one that I failed to take. Off to go investigate clearance
Quiklilcav wrote:Ryan Thompson wrote:can someone answer this ? 4 me please? does the 3.4 have the same mounting as the 3400? and with it being taller would it fit in the cav? please help.
No, if you are talking about the 3.4DOHC from the Cutlass (and a few others), it does not have the same mounting points. This will require some major mods. The engine is also a lot wider, due to the DOHC heads. DoubleZed did it in a vert. It's a nice swap, but only the 3100 and 3400 swaps have the almost bolt-in simplicity.
thank you sir. now that thats been cleared up i know what direction i am going in the swap. i think im going to make a project log for myself and others (mainly so you can give me tips when i @!#$ it all up, lol), but i have begun disassembly of the 3100 right now its down to heads and block. my friend who rebuilds motors professionally claims the 3400 heads & intakes should bolt up, and that the 3100 can be bored out that extra 3mm and use the 3400 pistons... not sure how true that is, but we will see where it goes
