S12 Engine Swap Guide

Started by Arro · Jun 8, 2009 · 64postsSMF 2010–26

Scootin' ScottDec 19, 2009, 10:28 pm · #51

Will any KA24DE work? Say, one from a newer Altima? Or are the mounts different since it's FWD?
Are we basically limited to s13/s14 KA's?

BTW I'm sooo glad this thread is here. Really breaks down all the options really well. Thanks for the hard work Arro!

XanoDec 20, 2009, 2:46 am · #52

Stick with the RWD KA.

It is possible, but you'd need a lot of parts FROM a RWD version to swap onto it.

That holds true for ALMOST every FWD nissan engine, though DEFINITELY not all of them.

Scootin' ScottDec 20, 2009, 2:51 am · #53

K. Kinda what I figured. Thanks!

tommyJan 13, 2010, 4:19 pm · #54

JayThe SR is a square engine along with being better balanced. (Which for those who don't know, means the Bore = Stroke, and in the case is 86 mm)

KA's are HALF couterweighted cranks.
SR's are FULL counterweighted cranks.
CA's are HALF counterweighted cranks

I'm not sure on the other more exotic engines though, If someone else can add those it would be sweet.

But! Because of that, the SR's are more rev happy. Don't need to go any deeper into that subject here though.

Thx for the guy who brought this thread from the dead... I don't know how this passed unoticed by everyone, but this reply here is pointless....

The CA is 83mm X 83.6mm which makes it a "square" engine to me.

The number of counterweight doesn't mean anything... in fact, a half counterweight crank will spin faster to it's maximum rev, as long as it is balanced, it's like an lighten flywheel, it doesn't allow more rev, it makes it climb the revs faster. A full counter weight crank will in fact have more inertia then their half weight counterpart, but they tend to be a little stronger, which has nothing to do with rev at all.

IMO the cam on bucket valve train that the dohc CA uses is WAY more efficient and will permit more revs via less parasitic friction loss then the stupid rocker system that the sr is stuck with. Valve are easier to adjust with the rockers, but involve a lot more moving parts, so a lot more shit to go wrong.

The main reason why nissan faded out the CA was because the SR was cheaper then the CA even more if you take into account the cost to maintain it... timming chain vs timming belt, twice as long to adjust valves clearance for the CA, etc....

If the SR would have had a better valve train, the skyline would've used it for sure, being the top nissan sports car, but you guys can ask draco what's in the rb20 and rb26....

seishukuJan 13, 2010, 5:30 pm · #55

Bucket lifters may have less to go wrong, but the SR has less frictional loss due to the fact that there's only one cam lobe to operate two valves.
Not that it makes any difference in the power output anyway.

The only thing that makes the SR valve train bad, are the crappy hydraulic lifters. High revs cause them to collapse, and out pops a rocker arm. Revised hydraulic lifters somewhat fix the problem (found in newer FWD US SRs, and are good for a few hundred more revs), or switching to a solid lifter (rev until you break a crank).

ArroMar 5, 2011, 4:23 am · #56

Did some new editing on the original post, added a Q&A about FWD engines. Newbies are encouraged to read this thread, especially the original post!

VG33ERGazelle?Mar 5, 2011, 9:22 am · #57

this is an excellent guide, very concise and informative.

but you should add the VG33E/R swap in there somewhere. It's really not hard, it just takes a little know-how and some wiring.

ArroJun 5, 2011, 2:46 pm · #58

It's not a common swap, nor is it documented, and I do mention its supercharger towards the end. At any rate, your post should be enough to serve as suggestion for it, as anyone with the know-how to try it will likely have read at least this far in the posts ;)

sinsFeb 9, 2012, 9:52 pm · #59

Hey Arro. I see that you're in SoCal too. Can you recommend me a mechanic/auto shop where I can get a swap done. I got an 1985 2.0 non-turbo auto tranny. I would like to quote for swap; something with a turbo and auto to 5 speed conversion, if it's possible.

I_heart_VVLFeb 12, 2012, 10:07 am · #60

I'm pretty sure no one in socal specializes in S12s, but SR20store in Gardena has a very good reputation for their SR swaps into 240s, you should give them a call.

sinsFeb 13, 2012, 12:11 am · #61

cool. ty.

Post Merge: 03:25:47 PM / 13-Feb-12

I checked with the SR20Store and they said they can do it. The only problem is that it won't be SMOG legal in California. I don't want to just rebuild the engine. I want to make this car fun to drive. What are my other options?

I_heart_VVLFeb 13, 2012, 8:13 pm · #62

well that makes sense, since no JDM will be completely legal in the US ever.
I'm sure there's ways you can get around smog in cali tho, there's TONS of 240 guys running SR/RB swaps.

or you can also do a KA24 swap, to keep the cost down and itll be easy to smog. Another option would be a VG30 swap from an SE S12. Of course these engines don't make nearly as much power as a stock redtop SR20 though.

sinsFeb 15, 2012, 9:03 am · #63

haha. thanx. if i can't get a hold a ka24 for a good price. i'll try to find a shady smog tester.

ArroMar 15, 2012, 12:33 am · #64

You need to contact Marco at sr20store.com because as the name implies he has the hook-up for SR20DET's. He can either get you the engine and trans and ECU and you can have a local member come and help you do the swap yourself (as a number of SoCal guys can do this), or you can ask Marco for a quote to do the swap on your car himself. He did the first SR20DET swap into an S12 back in the early 2000's for his son Cesar's car. He knows the S12 and he knows the SR, KA, and RB engines very well. His shop is just off of Artesia in Gardena.

As far as getting past smog in CA... you're gonna have to make the right kind of friends. Which isn't impossible.