Is a 3.6l engine swap right for me?

[A&F]

Long story short my 130k mile 3.2 took a crap on me. I’ve been too apathetic to diagnosis the issue. Either a rocker exploded or a rod cap came off. There is aluminum in the oil. Whatever the case maybe, the case needs to be split. (get it it?, case)

I’ve been reading books, reviewing build threads and building spreadsheets of pricing. Case splitting is not cheap or easy. I could stomach it more if I knew I was getting something better in the end, but that doesn’t seem the… case.

I took notice to 3.6 engines being listed for sale on eBay by LA Dismantlers. $8-11k is going rate and it even has an entire 90 warranty!! (not actually excited). My understanding is a larger/additionally oil cooler is needed. These bolt up to the 915, but I have heard people say the 915’s can’t handle the power, is that true? ~250ft/lb is too much? (that’s terrible).

I’m thinking parting out my 3.2 would go a long way to paying for a 3.6. I figure 10k – 4k = 6k out of pocket which is what a rebuild would run me. Back date the heat system, sell the 3.6 heater equipment and DME and install a MS3 ECU.

Is this a wise thought process or will a 3.6 run an even greater potential for being another broken money-pit?

[Flat6pac]

Its less to build what you own
The3.6 purchase is just the beginning, then you need Steve Timmins @ instantG and the parts store in Phoenix.
You really need to find out the problem with the 3.2
Bruce

[A&F]

Originally Posted by Flat6pac

Its less to build what you own
The3.6 purchase is just the beginning, then you need Steve Timmins @ instantG and the parts store in Phoenix.
You really need to find out the problem with the 3.2
Bruce

Even if I want an extra 70whp?

[clutch-monkey]

915 handles 3.6 fine.
better off building the 3.2 to a 3.4/3.5 or something.

case splitting isn't very hard. putting it back together might need supervision though..

[porterdog]

You have to compare the end results to really understand the equation. Known good 3.x (your rebuild) vs. unknown 3.6 that may require ?? at some point sooner than the recent rebuild.

Tough call!

[johnsjmc]

A 3.6 is a bit more involved than a bigger oil cooler.
The 3.6 doesn,t have any oil cooler so you need double the coolers.
Then the flywheel is different ,so are some of the oil lines. The power steering pump on the 3.6 is removed ,sheet metal shrouding needs to be trimmed. The wiring is different even if your new engine includes the DME and harness. If a 96 or newer then there are dme programming(drivebloc) issues.The 3.6 exhaust from a 964 doesn,t fit. You could use the exhaust from the 3.2 but it will restrict performance.The 993 heat exchangers are good but the flanges need to be cut off and rotated 90 deg and reattached on the pass side only Then you need a custom muffler and if you need to pass smog it,s even more complicated. I,m sure I,ve forgotten something as it,s been a few years since I did one. I think Timmons basic kit is $3500 plus engine maybe 25-30 hrs labour . His kit doesn,t include any oil coolers or exhaust either.
Your cheapest option is probably a good used 3.2. Then you have a simple bolt in and you,re back on the road.

[Bill Verburg]

Originally Posted by johnsjmc

A 3.6 is a bit more involved than a bigger oil cooler.
The 3.6 doesn,t have any oil cooler so you need double the coolers.
Then the flywheel is different ,so are some of the oil lines. The power steering pump on the 3.6 is removed ,sheet metal shrouding needs to be trimmed. The wiring is different even if your new engine includes the DME and harness. If a 96 or newer then there are dme programming(drivebloc) issues.The 3.6 exhaust from a 964 doesn,t fit. You could use the exhaust from the 3.2 but it will restrict performance.The 993 heat exchangers are good but the flanges need to be cut off and rotated 90 deg and reattached on the pass side only Then you need a custom muffler and if you need to pass smog it,s even more complicated. I,m sure I,ve forgotten something as it,s been a few years since I did one. I think Timmons basic kit is $3500 plus engine maybe 25-30 hrs labour . His kit doesn,t include any oil coolers or exhaust either.
Your cheapest option is probably a good used 3.2. Then you have a simple bolt in and you,re back on the road.

A single good sized B&B oil cooler in the valance is sufficient for street use w/ up to a 3.8RS engine, for track use you will want as much cooler as can be fitted, the 993s use dual large Setrabs w/ excellent results a 911 can be setup similarly w/ dual radiator in the 2 fenders, I believe that Elephant even has a kit for this.

Yes you will need a conversion flywheel and any good 915 compatible clutch

Drive-block can be found in any 993, the big difference in wiring is the OBD1/OBD2 divide, through '95 on US and all n/a RoW 993 and all 964 are OBD1 w/ relatively simple 55pin harnesses, these all can be easily chipped which will negate any t/p drive-block issues on an OBD1 993 a relay bypass is also needed but this is unnecessary on a t/p) The tougher ones to work w/ are the '96 up US 993 engines which have OBD2 DME w/ 88pin harnesses, the '96 is a unique year and cannot be easily chipped or re-flashed, best advice is to replace w/ a '97/98 DME which can at least be re-flashed by a shop w/ the proper skill/tool sets

964 exhaust setup is identical to earlier version, to use a 993 header the right side flanges need to be rotated 90°. 993 heads have dual stud setups and can use either the old style or 993 style hookups

For smog compliance it' best to retain the entire exhaust to the cat that was used on the donor car, this can usually be made to happen.

Since the 3.6s are getting older and are as likely to need a rebuild as what you have the question becomes more like-- What rebuilt motor do you want in your ride?.... MY answer would be a 993, you cannot beat the torque and reliability but for others originality will be more important, in that case rebuild the stock engine

[johnsjmc]

[QUOTE=Bill Verburg;8131214

964 exhaust setup is identical to earlier version, to use a 993 header the right side flanges need to be rotated 90°. 993 heads have dual stud setups and can use either the old style or 993 style hookups

[/QUOTE]

I forgot the 993 engine has two sets of threaded holes at the cyl head flange. Flanges need to be rotated on the pass side if using a 964 3.6.
The 964 exhaust crossover between the two heat exchangers WILL interfere with the clutch throwout lever.(or something near it IIRC).

[Bill Verburg]

Originally Posted by johnsjmc

I forgot the 993 engine has two sets of threaded holes at the cyl head flange. Flanges need to be rotated on the pass side if using a 964 3.6.
The 964 exhaust crossover between the two heat exchangers WILL interfere with the clutch throwout lever.(or something near it IIRC).

I could have been clearer

You can use the stock/existing 3.0 or 3.2 exhaust on a 964/993 t/p. Doesn't matter if it's the oe or an ssi version. The sizing will be a bit small for high rpm use but for normal around town use it's fine. A 964 oe exhaust is the same design just w/ larger pipes which can interfere w/ the clutch setups w/ helper springs used from '77

On the pre '77 cars the clutch mechanism will be clear of of any of the oe exhausts
here is a 964 engine in a '76 w/ B&B headers


same engine w/ ssi


unfortunately no pics w/ stock 3/3.2 or 964 exhaust but they would have fit as well

[r-mm]

Ask you doctor if a 3.6 is right for you.

Do you do your own maintenance? Because its a lot easier on a 3.2. But then again, there are just about no valve adjustments on a 3.6. Everyone I've spoken to that has done the swap is pretty damn pleased with it, and if you get used to putting it in/taking it out, it might not be so foolish to find the best one you can, compression test it etc, then just put it in without any major rebuild work.

On the flip side... I am squarely of the camp that it is more fun to drive a slower (but still pretty goddamn fast) car fast than a beyond-fast car slow. I love pulling to redline in all gears (okay mostly 1,2,3) on my stock rebuilt 3.2. Had I gone for 3.4 high comp, steve wong, etc I'm sure I'd love it even more.

[michael lang]

Either way you go, unless you make foolish decisions, you can't go wrong. There are advantages to going 3.6l. Power, everything updated, very popular upgrade. In my opinion, the 3.2l rebuild is really the only choice. Who knows what happened to cause your engine to implode the way it did but that's irrelevant. I too am of the belief that if you can drive a slow car fast then you can drive anything fast. The single biggest advantage that I find as I go through my own rebuild is the feeling of accomplishment I have when I put my tools away after I have finished. I'm still a very long way away from being done but with work schedule, all the stuff that my wife & I do around the house, the kids stuff their involved in...there isn't a whole lot of me time left over so I fit it in when I can.
There's so much material available to walk you through doing it yourself, all it takes is breaking it down step by step. I was very intimidated about it at first but you can't look at it like that, if you break it down into smaller individual projects instead looking at like a complete rebuild it becomes much more manageable. There's absolutely nothing wrong with my engine, I'm only doing upgrades like 964 cams and exhaust but while the engine is out I'm just going through it and cleaning, cleaning and more cleaning of engine parts. If I see something along the way that needs to be addressed, I'm already there so I just take care of it. Best of luck in whatever you decide.

[wanderlust]

in reply to r-mm's comment
Do you do your own maintenance? Because its a lot easier on a 3.2. But then again, there are just about no valve adjustments on a 3.6. Everyone I've spoken to that has done the swap is pretty damn pleased with it,


Just a clarification on the "about no valve adjustments on a 3.6L - I'm not sure if I miss something on the post and I want to make sure if I am being taken by my mechanic. He told me I need to adjust the valves on my '92 3.6L motor EVERY 15k miles? True or not? thanks

But I do agree with being happy with the choice I made at that time - I had 3.6L transplant into my '77 about 9k miles ago and still tweakin' it. I was trying to upgrade my early heat exchangers to the 964 heat exchangers and sure enough the fork is in the way. I am now exploring installing the 993 heat exchangers, like to know the issues besides reversing the flanges...

[johnsjmc]

a 964 3.6 still requires valve adjustments. The hydraulic lash adjustment showed up in the 993 engine.

[JeremyD]

and from experience - Only buy a used engine if you consider it a core for rebuild - Low mileage / leakdown -- Unless you have personal experience with the engine in question - take everything with a grain of salt.

[johnsjmc]

I was trying to upgrade my early heat exchangers to the 964 heat exchangers and sure enough the fork is in the way. I am now exploring installing the 993 heat exchangers, like to know the issues besides reversing the flanges...[/QUOTE]

When you rotate the flanges on the pass side on 993 HE's. The studs that were accessible from below through the tubes built into the HE's no longer line up. This leaves a couple of the nuts almost ,but not quite, impossible to reach.
When you weld the flanges back on make sure you have them attached to some kind of fixture(I bolted them to a piece of 3/4 plywood ) to maintain them all in the same plane.

[67dubcab]

What he said about aligning the bolts, my fabricator did a good job and I still had to open up a few bolt holes, also needed to put it on a long belt sander to flatten out the flanges to the same plane, the heat from welding is enough to cause bias. I think he drilled out a piece of steel with the correct bolt pattern to hold it as a jig.
The heat exchanger flanges on the top foul the valve covers and need to be cut down a bit, as those covers still need to come off for those pesky lash adjustments! (pre-993 3.6)

Those nuts a are no fun either, need cut-down wrenches and beer given patience to take on and off.