Street Performance 3.2 Rebuild
 

Hi I'm Mike,

I live in Brisbane, Australia and own a 1970 911 that has been modified to resemble a 964 American Roadster.

http://forums.pelicanparts.com/uploa...1327624009.jpg

I have had to do a rebuild on the 3.2 as it spun a big end bearing on number 2 cylinder. After stripping the engine completely I was releaved to see no real damage has been done other than some scoring on the crank journal and the conrod.

While I have the engine apart I have decided to do an upgrade to gain more performance. I don't want to go down the twin plug path at this point in time but would like to get the most out of it without going overboard.

I have the book "how to Rebuild and Modify Porsche Engines 1966 - 1989" and was looking at the recommended 10.3:1 Mahl pistons and cylinders to make it Euro specs. Also back dating the exhaust system to an SSI and Dansk twin in twin out muffler.

As far as other possibilities I am unsure what I should do especially as far as cams go. I am going to send the heads out for a reco and port matching and polishing and have a Motronic injection system and was considering a chip of some sort but not sure what to do here either.

Any help would be greatly appreciated.

Cheers Mike

The only language we know here is "go over-board all the time, as often as possible and pray the wife doesn't find out". :-) Just kidding...

OK, i'll throw out the first question, what is your budget?

And a couple of suggestions:
1. Since you want to stay single plug, look at another thread by "dipso" 10.5 CR on single plug. Some really good advise in a relatively short thread.

2. There is some good data on Steve Wongs site, 911 chips. Read through the dyno charts and the different mods some folks have done. This might give you an idea of what to expect for certain mods. 911Chips - Porsche Dyno Runs

Cheers for the reply AlfonsoR,

I will check out the thread you suggested and the website concerning the chips.

As for the budget, I am looking to spend up to $15000 on the upgrade which part of this includes a new clutch, WEVO 915 Shift Kit and various tools to help complete the job. So I would say 13K just for the engine rebuild. I will be doing the assembly myself but I am yet to send the heads, crank, case, rods etc. for machining. If I go over budget so be it but I would like to stay closeish to this figure.

As far as the wife goes she is pretty good about this kind of thing so I don't have to hide anything. She's a keeper :)

I just had a look at the thread by dipso and realised that I had read this just before I made my post. I considered what was said in this post at the time but thought as I run on 98 octane I would be able to get away with the higher compression ratio. Also in Waynes Top Engine Picks from the book he states that no additional upgrades are required for the 10.3:1 Euro Upgrade.

Being new to Porsche engine rebuilds I can only go by the information I have (Waynes book) but if people in the know suggest not increasing my CR then I will certainly listen.

I would like to do the twin plug upgrade at some stage but but after reading the different ways of going about this I decided that it could wait for another day until I do more research (and save more funds).

After reading many threads on the subject of twin plug systems I am very overwhelmed by the array of possible combinations but would really like to pursue this option in the future.

If I was to go down the twin plug rout, would it be advisable to have the machining done on the heads and lower valve covers and screw the plugs in until I am ready to change the distributor and other components?

Primarily I want to focus on the engine rebuild but would like to have this machining done now to save having to pull the engine out again if this is a possible option.

I just finished my rebuild.
It's a ROW car so I already had the 10.3:1 CR.
I added 964 cams, SSI's and an M&K dual in out muffler. The Wong chip was already in there.
I could have tried to get more out of it but for a street car, this will do nicely.
It has about 50 miles on it since I got it back from the shop. So it's not broken in yet. But I can feel the improvement over stock very clearly.
I say go for it!

When I Pm'ed Camgrinder, he suggested 964 cams or 993 supersport. I went with the 964 because I found a set that was like new and very cheap.

Cheers Geronimo '74,

Sounds similar to the road I was heading down, just wasn't sure what cams or cam profiles to go with. Good to know about the Wong chip as well, this being another grey area for me.

Does your engine have a twin plug setup?

After ploughing through this forum and others I am tempted to go for a more aggressive rebuild but not ready to upgrade the transmission if it can't handle the grunt. So need to take baby steps and do this in a logical ordered steps that will still allow me to get the car back on the road soon (having major withdrawals).

I have been looking at Clewett Engineering's Individual throttle body dual plug kit, has anybody had anything to do with this system and what other engine modifications would be required or am I just going overboard?

Do you already have something in mind for your rebuild? If all you need to do is turn down your rod journals, you may want to:
1. keep the pistons and cylinders you have
2. buy a nice set of rods R&R, Carillo, Pauter - $1800
3. send your heads to someone who is really good, like Steve Weiner or Xtreme Heads (not for increasing flow but for optimizing characteristics such as tumble, swirl, etc
4. install a set of PMO carbs - $4,000
5. Cams and springs ???

I guess my point is, if you really want a decent increase in power, it might be a better value (if you can re-use your Ps&Cs) to spend some cash on improving the breathing capability with carbs. ITB injection would be nice too but more money, I believe and more complex. Said another way, Motronic & the intake plenum are the biggest bottle necks to making power. The upgraded rods are just insurance for over revs.

Just throwing some ideas out there, I could be wrong. I need to rebuild my engine too (first time too) and you're right, the combinations are endless.

AlfonsoR when I first stripped the engine to assess where I was at in terms of damage because of the spun big end bearing I thought a quick hone, re-ring, bearings etc.

Then I had a beer and thought what do I really want out of this rebuild and decided a near new engine was the end goal. After more deliberation (beers) and more research I thought Waynes Euro upgrade with a few other mods was for me.

Now having decided after much research to go down the twin plug direction I am of the opinion that I may as well increase the displacement which brings up other issues, my biggest concern being the Motronic Intake plenums and throttle body.

Also being a computer nerd I would like to stay with injection and a programmable engine management system (more research required).

Having read a great article at the European Car Website (a long article over 5 posts which are hard to navigate but I got there in the end).

Porsche 911 SC Carrera Engine Buildup Project Car - European car Magazine

I am really liking the sound of this rebuild which also gave a pdf of parts used and part numbers.

I am leaning towards this rebuild as a base and making several other changes the author of the article could not make due to smog restrictions that will not effect me where I live in Australia.

I am getting closer to making the theory engine I believe would be the one for me but still want to explore all possibilities before I send things out to be machined.

Here are some pics of where I'm at, I will post more when there are more pics but I am planning on taking a lot of time to plan and implement this rebuild.

Engine Out.


http://forums.pelicanparts.com/uploa...1327729608.jpg

What a dirty dirty engine.

http://forums.pelicanparts.com/uploa...1327729662.jpg

Most parts cleaned, painted or polished.

http://forums.pelicanparts.com/uploa...1327729569.jpg

Dr,

I was planning to go the 3.4 route too but my budget quickly killed that dream.

Whatever you do, make sure your gearbox is in good working order (if it isn't already)
You won't enjoy your the upgraded engine if it is married to a crappy trans...

Hey G-man I have given this some thought as well, my tranny is a 915 that is still in the car but will be out as soon as the rain stops (fingers crossed tomorrow) for inspection.

Hopefully the 915 will be up to the task but only time will tell.

If you are going to 3.4, with some other mods, and are keeping the 915 tranny, it needs to be in good shape.
Is it a younger model 915? WitH the additional oil cooler?
I don't know if the older gearboxes will like the extra horses and torque.

Being new to the Porsche world I had no idea there was other versions of the 915 trans.

I was in the back of the car yesterday and did notice a cooler coming off the left side of the trans. So I am now assuming that this makes mine the older version. :(

I had not planned doing the trans during this rebuild and will just have to see how long it lasts once I am finished. It should be OK during the run in stage but after that it probably won't last too long and I will be doing the G50 transplant sooner rather than later.

http://forums.pelicanparts.com/uploa...1327795381.jpg

I'm not an expert on 915 gearboxes either.
It just seems logical that the "youngest" versions should be more capable dealing with higher HP numbers. The added oilcooler from the latest versions would help too.
A G50 will be more than strong enough, I reckon.

The later versions 915 had the oilcooler. ;)
(I believe '86 and onwards)

If you are planning to switch. It's not a plug and play job...

http://forums.pelicanparts.com/porsche-911-technical-forum/654150-can-you-replace-915-trans-g50-easily.html

Thanks G-man for the insight I obviously read your post wrong (stupid me :confused::confused:), so my trans will probably last a little longer and might still be worth doing the Wevo sift kit upgrade.

I would eventually like to upgrade to the G50 with a hydraulic clutch (at the moment the pedal is so darn heavy).

Thanks again for your help.

OK for those interested, the rain stopped just long enough for me to remove the trans and axles.

The photo does not show all the crud on the trans because I degreased and hosed off before I started but boy was it covered in oil none of which was from the transmission itself.

Had a quick look at the oil (still have to drain for a proper inspection) and I was surprised how good it looked and smelled.

A dirty dirty tranny.

http://forums.pelicanparts.com/uploa...1327833189.jpg

And after some love with more degreaser, an old tooth brush and the garden hose with a high pressure nipple.

Cleanish tranny

http://forums.pelicanparts.com/uploa...1327833739.jpg

And here is how bad I looked after wading through the crud to remove the trans.

http://forums.pelicanparts.com/uploa...1327839044.jpg

Here in the US we can buy latex surgical gloves. An entire box of them isn't $10...
:)

Well done, mate. The grease smears are badges of honor. :)

I have tried wearing gloves before and they are also cheap here in OZ but personally I prefer the full feeling you get without them. And because I no longer do this as a day to day job I don't mind getting down and dirty once in a while. :)

Thanks Flieger, I think I will earn a few more badges of honour before this project is done and dusted. :)

Having the plug holes machined now while you have the heads off is a good idea. 98 Octane will keep things in check until they start watering petrol down like they do in california and US. However, If you are are planning to go the 3.5 route with 100mm P&Cs like the article you linked too, then you may want to set up for sending spark to those other 6 plugs now. You will not have to run as much advance to get flame across the entire cylinder which is why Porsche went twin plug on the 3.6.

I would also suggest sending an email to John Dougherty aka camgrinder. He will definitely steer you down the right path for cam selection.

You can get much improved engine performance sticking with motronic. While you can't use really radical camshafts, what you have listed along with an exhaust backdate will certianly make you smile when you step on the go pedal.

BTW, do you happen to know Chris Walker? He's from Brisbane & does fairly well in local PCA events with his Boxster.

Hi joetiii thanks for all the good advice, I will be keeping the car off the road for longer :( and sort out the twin plug system while the engine is out of the car.

I would like to go the bigger displacement pistons and I am thinking JE 98mm pistons 10.5:1 and a set of Nickies. I don't want to get the extra machining done on the case as I would rather leave the meat of the case alone, I tend to get paranoid about things like that.

I will certainly send John Dougherty aka camgrinder an email when the time comes to do the cams. I don't want anything too radical because I drive this car to work regularly.

No I don't know Chris Walker but will keep an ear out for the name in future.

Ok I think I have narrowed it down, please feel free to give me advice on any of the following:

JE Pistons 98mm 10.5:1 CR
Nickies Cylinders 98mm
Crankshaft - magnaflux, micro polish, cross drilled & balanced
RACEWARE Connecting Rod Bolt Set
Supertec Performance Cylinder Head Stud Kit

Heads
Port matched and polished
High Performance Valve Spring Set with Titanium Retainers ??? (Not sure if necessary)
Phosphorus bronze Valve Guides
And general cylinder head refurb

Dougherty Cams ???

Standard Motronic injection system
Twin Plug System ???
Steve Wong chip

SSI Heat Exchanger
M&K Exhaust Stainless Steel Muffler

I haven't posted in my engine rebuild thread for a long time so here are some update pics (not engine related sorry).
I have been waiting for a crankshaft to arrive from the US for 4 months now and still waiting.
So I have found other things to do so I feel like the project is still moving forward.

http://forums.pelicanparts.com/uploa...1341487227.jpg

Welded a few tiny spots of rust I found in the floor.

http://forums.pelicanparts.com/uploa...1341487256.jpg

Sealed the floor with Killrust.

http://forums.pelicanparts.com/uploa...1341487364.jpg

Custom made speaker shrouds shaped and ready for fibreglass.

http://forums.pelicanparts.com/uploa...1341487288.jpg

Superlite Dynamat fitted. And yes I know you don't need full coverage but I had purchased a 12 sheet box before I learned that.
Still it looks cool.:cool:

http://forums.pelicanparts.com/uploa...1341487339.jpg

Parcel shelf made and test fit ready for covering. Yes I am a nerd I like transformers so a mate and I made custom rear seat backs.
(Haters gunna hate).

http://forums.pelicanparts.com/uploa...1341487483.jpg

Fitting Rennline pedals and boards.

I have just bought another 3.2 to put in while I wait for parts. I really want to drive my car again. (I couldn't wait any longer).
Should be back on the road soon.:D

Your interior work looks great! Thanks for the update...

But, what is the rest of the engine story -- and why is the crank in the US??
Or, did you have to buy a new/used crank to replace your original one?


Best of luck,

Thanks Roy,

The story with the crank is; I could not find a good 3.2 crank in Australia at the time (but one has come up since:mad:) so I bought a magnafluxed, cross drilled and micro polished crank from a fellow Pelican (Bob Barnes) that had it preped for one of his race engines.

I have been trying to contact him for about a month now regarding the tracking details but he is yet to get back to me.:(

I put a post in the tech forum to find out if anyone knew what the go might be with Bob and have since got a contact phone number that I will call soon.

I am confident he will come through for me but I am getting impatient to drive my car, hence buying the other engine to get me by.

On a good note (and engine related) I saw my machinist yesterday and gave him the new valves, guides and seals to complete the twin plugging and refurb of the heads.

Another update for my engine thread.
My crankshaft still has not arrived :rolleyes: (long story) but a on a good note I have managed to buy a spare engine (for a great price) to use while I build my good engine.
And my interior is almost finished so I should be back on the road again soon. :)

http://forums.pelicanparts.com/uploa...1345114379.jpg
Spare engine pimped out.

http://forums.pelicanparts.com/uploa...1345114431.jpg
Parcel shelf with Porsche lettering.

http://forums.pelicanparts.com/uploa...1345114455.jpg
Sliver knit carpet fit by yours truly (just need to cover the speaker shrouds).

Nice work :)

Are you sure it is not a RoW 3.2 you have all ready? Your trans with oil cooler looks exactly like a RoW 84-87 trans.

Check the numbers on engine and box :)

Yes I was thinking that as well. I thought all Aus spec cars were ROW spec.

Hi soren.911/whiterabbit,
Researching the engine number tells me it is a US engine. I haven't checked the new (spare) engine yet but will keep you posted.

Here is a pic of what I managed to get done today. Very excited the engine is back in the car. :D

http://forums.pelicanparts.com/uploa...1345279810.jpg

Mike, you have a private message from fellow Brisbane Pelicanite
Cheers, Paul

Hi Paul,

Thanks for the PM will give you call sometime this week.

Cheers

Mike

Hugely interesting thread. I was mildly disappointed you went away from the 3.2 with 10.3:1 compression. I'd love to have seen how you went with that since that is what is on my shopping list.

As a heads up, I was quoted $20k for a 3.4 build (Mahle P's and C's, extrude hone, camshafts etc) from a shop in Sydney (good shop with plenty of race car pedigree).

I'd prefer to stick with the 3.2, though, and maybe get my own fingers greasy - I have not a mechanical bone in my body. My car is pretty well sorted - upgraded hollow TBs, sport bilsteins, brakes, roll cage, wevo mounts and short shift kits, 1988 3.2 (930/25) 40,000 kms ago, rebuilt gearbox 80,000 kms ago, SSIs, but a bog-stock 2 in 1 out.

So my idea was like your original, high comp 3.2, no dual plug (98 Octane is plentiful and high quality), maybe a new cam grind - kinda a "warmed over" 3.2. LSD and 2 in 2 out as well?

It's "how fast can I afford to drive" :)

BTW, where were you planning on sourcing your M&K?

Hi Tigrah,

Thanks for the comment.

I haven't abandoned the 3.4 build it's just the crank has been taking so long to arrive from the states.

I managed to find this engine at a good price so have installed it to keep me driving the car while I wait.

The heads are at my machinist being twin plugged and as soon as the crank arrives I'll be back on track to do the build as planned.

As for the M&K I was hoping to source one here but was preparing for the worst if I have to have one shipped from our host.

As an FYI, it's a lazy Sunday afternoon here so I decided to inquire as to whether M&K had a distributor in AU. They responded in 10 minutes flat! here's the skinny:

No distributor but "The dual out muffler shipped to AUS is $870. We have one in stock and can ship Monday. Transit time is 6-10 days depending on exact location."

That's probably one of the easiest ways to spend money I've seen!