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3.4 DOHC swap

Posted: Sat Feb 06, 2016 9:49 am
by delorehal
I would like to know, if it is easy to put a 3.4 DOHC engine (from a Cutlass auto) to a beretta with a 3.1L and manual trans.
Does this require new mounts, new ECU, ...

thanks for your help

Re: 3.4 DOHC swap

Posted: Sun Feb 07, 2016 12:47 pm
by themixer
interested in any information on this !

Re: 3.4 DOHC swap

Posted: Sun Feb 07, 2016 8:01 pm
by 1988GTU
will require unibody, core support, & subframe fabrication. new ems, different mounts,

Re: 3.4 DOHC swap

Posted: Mon Feb 08, 2016 12:59 pm
by delorehal
Thanks,

I thought it would be easier to do this swap.
Can the manual trans of the 3.1L be used instead of the auto tranny that comes with the 3.4L, or the belhousings are different ?

Is the 3400 swap easier ?
In this case, I would have to look for a FWD car (no camaro or Pontiac), right ?

Re: 3.4 DOHC swap

Posted: Mon Feb 08, 2016 4:55 pm
by ronaconda
The 3400 swap is much easier and, simply, will fit in the engine bay of the Beretta. I remember seeing a pic of someone putting the 3.4 DOHC in the engine bay of the Beretta and there was little to no room for anything else.

Re: 3.4 DOHC swap

Posted: Tue Feb 09, 2016 6:29 am
by 3X00-Modified
My opinion.... You need to lower the subframes on a W-Body to change the alternator... I can only imagine you'd have to pull the engine to change the oil if you put it in a L-Body... LOL

Sent from my Nexus 5X using Tapatalk

Re: 3.4 DOHC swap

Posted: Tue Feb 09, 2016 1:30 pm
by Red_Bra_Black_GTZ
Question, is the 3.4 LQ1 as bad of an engine as I am hearing? I mean reliability, longevity etc.

Re: 3.4 DOHC swap

Posted: Tue Feb 09, 2016 3:00 pm
by 3X00-Modified
probably... Depends on who your hearing it from though.

Re: 3.4 DOHC swap

Posted: Tue Feb 09, 2016 3:04 pm
by Red_Bra_Black_GTZ
Fiero group, other internet sources. Boards.

Re: 3.4 DOHC swap

Posted: Tue Feb 09, 2016 3:44 pm
by delorehal
This swap is not for me.
I like the 3.4 though, it is like if it was a QUAD 6 engine (and the Northstar a QUAD8).

Re: 3.4 DOHC swap

Posted: Tue Feb 09, 2016 6:32 pm
by 1988GTU
If you service the t-belt and its respective pulleys/tensioner, it's a stout beast. BUT why date as well as limit your performance with even more harder to buy good quality parts for? Minds well toss in a 3800 series 1.

Re: 3.4 DOHC swap

Posted: Tue Feb 09, 2016 6:34 pm
by Red_Bra_Black_GTZ
My thoughts, I like a 4 valve per cyl. Engine, it is also a high revving engine.
It puts out 280 hp

Re: 3.4 DOHC swap

Posted: Tue Feb 09, 2016 7:48 pm
by nocutt
delorehal wrote:I would like to know, if it is easy to put a 3.4 DOHC engine (from a Cutlass auto) to a beretta with a 3.1L and manual trans.
Does this require new mounts, new ECU, ...

thanks for your help

It is actually easy...assuming you know how to fabricate metal...has huge HEADS ad as already mentioned clearance at the back must be incorporated into the swap...
As already stated, you will need a lot more than you may be thinking. It is a beautiful engine, but it is dated and hardly any aftermarket for it these days. Don't listen to anyone telling you the engine is bad...all engines have their respective short comings. The first other of business if and when you get this engine is to "freshening it up"...again the assumption is you know your way around an engine...if not be realistic...

Red_Bra_Black_GTZ wrote:My thoughts, I like a 4 valve per cyl. Engine, it is also a high revving engine.
It puts out 280 hp
It is high revving, but it does NOT put out 280hp n/a...even with modification outside of force induction...

Re: 3.4 DOHC swap

Posted: Wed Feb 10, 2016 6:15 pm
by 1988GTU
280 is kind of stretching it. Fab in a turbo and the 3.4tdc wakes up... If the 3.4tdc has a tough time fitting as is in a L body, imagine the additional headaches of a traditional turbo setup. omfg is lightly putting.

Re: 3.4 DOHC swap

Posted: Thu Feb 11, 2016 2:17 am
by delorehal
IIRC, someone made 280 WHP by porting the head.
With a turbo, one put 417whp and 427wtq at 14psi (http://www.homemadeturbo.com/forced-ind ... uild-97661)