3.2 to 3.4?

[PorscheGuy79]

What is required to bump up a 3.2 to a 3.4? Is it just pistons and cylinders? Are there common upgrade parts to do while you are in there?

[asphaltgambler]

Try the search feature here. There have been many 3.4 conversions with different objectives and $$ spent

[PorscheGuy79]

Originally posted by asphaltgambler
Try the search feature here. There have been many 3.4 conversions with different objectives and $$ spent

3.4 wasnt an availible search term because it came up with 0 related threads. I will try "engine" and such but I was hoping someone wouldnt be bothered to post their knowledge.

Im preatty sure I figured out my answer anyway.

[gestalt1]

the P&C are basically the only difference. but do plan on chamfering the heads to meet the 98mm cylinders. also make sure they are 98mm pistons for a carrera, not an SC. the wrist pins are different size and location in the piston. also keep[ inj mind this is when you may want to increase compression, with the 98mm size twin plugging the heads is a good idea.

[PorscheGuy79]

Originally posted by gestalt1
the P&C are basically the only difference. but do plan on chamfering the heads to meet the 98mm cylinders. also make sure they are 98mm pistons for a carrera, not an SC. the wrist pins are different size and location in the piston. also keep[ inj mind this is when you may want to increase compression, with the 98mm size twin plugging the heads is a good idea.

Thanks! Thats just what I needed.

If you didnt hear about it my father, who you met at dinner at RAM, miss shifted and so far seems to have bent all the exhaust valves. He is looking into a 3.4 upgrade as a "while you are in there".

[JeremyD]

Let me recommend:

3.4 mahle 9.8 to one jugs
extrude hone intake
993ss cams
arp rod bolts
supertech head studs
enlarged throttle body
competition springs and retainers
964 B & B headers

[cstreit]

ARP rod bolts are certainly a must with the 3.2...

However with a set of Nickies and properly done J&E's the heads do not necessarily need to be reworked. 9.8:1 with 98's is fine on 93 octane here in the Midwest, though I don't think I'd run it that way on California gas on a hot day.

That's a nice setup Jeremy, but for the end-result you could plug a 3.6 in there for the same cost and more HP....

[88-diamondblue]

Here is what I did on my 3.4 upgrade/rebuild. QSC/JE from Supertec and PP is looking at selling them also.

[Jeff Alton]

I did (am doing) JE's with bored and plated Mahles from EBS. 10.5:1cr, DC44 cams, B&B headers, twin plug, Jenvey ITB's, Microtech ecu with digital dash, boat tailed case, race springs with Ti retainers, ARP head studs and rod bolts. I had my machinest chamfer the heads ever so slightly, even though the JE piston is designed to not need it.

Here is some pics.....









Cheers

[dean]

Originally posted by catca
I did (am doing) JE's with bored and plated Mahles from EBS. 10.5:1cr, DC44 cams, B&B headers, twin plug, Jenvey ITB's, Microtech ecu with digital dash, boat tailed case, race springs with Ti retainers, ARP head studs and rod bolts. I had my machinest chamfer the heads ever so slightly, even though the JE piston is designed to not need it.

Here is some pics.....









Cheers

If you ever finish the thing I am just teasing you

[JeremyD]

Originally posted by cstreit
That's a nice setup Jeremy, but for the end-result you could plug a 3.6 in there for the same cost and more HP....

Yes, probably a used 3.6 - but then you have the unknown of a used engine.

I have a totally reconditioned 3.4 now - and 244 at the wheels...

I sleep better at nights now.

[cstreit]

True, True.

The last one of these we used Max Moritz pistons and didn't chamfer the heads. I'm assuming you guys did the slight "bevel on the inner sealing-surface. What measurement did you use? What compression were the pistons?

[ChrisBennet]

I didn't bevel my 3.2->3.4 heads but I will when I rebuild it. The lack of a bevel trapped some foreign objects between the edge of the JE and the head. I think a bevel might have allowed the the F.O. to be squeezed safely out of the way.


I personally don't see the need for fancy head studs on a non-Turbo 3.2/3.4 motor. Of course, I also haven't got that much experience.
Anyone seen evidence of head lift on a one of these motors? Show of hands?

-Chris

[JeremyD]

Originally posted by ChrisBennet

I personally don't see the need for fancy head studs on a non-Turbo 3.2/3.4 motor. Of course, I also haven't got that much experience.
Anyone seen evidence of head lift on a one of these motors? Show of hands?

-Chris

I did mine for two reasons

#1 Corrosion resistance - I live 50 feet from Tampa Bay (saltwater)
#2 I was planning on turbo charging further down the road - but might just build a 3.6 turbo instead in the future.

[cstreit]

I've been using the starndard 993 steel ones on my N.A. motors for years with no issues. They are coated for corrosion resistance...

[Jeff Alton]

Originally posted by cstreit
True, True.

The last one of these we used Max Moritz pistons and didn't chamfer the heads. I'm assuming you guys did the slight "bevel on the inner sealing-surface. What measurement did you use? What compression were the pistons?

This pic shows the bevel, We just used the diameter on the bore as a guide. The pistons are 10.5 cr and when I cc'd the motor that is excactly what I measured, well it was off .00058 or something like that!!




Oh, and I could have bought 2 and half or maybe 3 used 964 motors for what I am into this one for.....

Cheers

[cstreit]

So you're chamfering the head to even the transition to the larger diameter bore... makes sense... I know when I went from 95's to 100's the area was so large there was no chamfer big enough.. The edges of the pistons were just flat...

Suppse that's not bad insurance since typically you'll be doing heads at this time.

[Jeff Alton]

The piston has a flat area around it's diameter, outside the dome. That is there to allow you to not have to chamfer the head. But, It seemed to me that would leave a "pocket" of sorts at the very outside edge of the combustion chamber. You would have the dome rising into the combustion chamber and the small flat area of the piston comming up against a ridge in the head- two level parallel surfaces facing each other with just your deck height between them. This just did not seem right to me, so we added the chamfer to create a better transition to the combustion chamber. Not sure if it helps or is even required, but it seemed to make more sense to me.....

It really looked odd holding the 98mm cylinder up to and unchamfered head and looking in through the bottom of the cylinder. What you saw was a 1.5mm ridge or flat area that the piston would be staring at.

Not sure if any of this makes sense, having a hard time putting thoughts into words tonight! I should have taken a pic up into the cylinder while it was against a head to show what it looked like.

Cheers

[Jeff Alton]

Having said all of that, lots of motors are designed with huge squish areas and small chambers that are like giant versions of an un chamfered 911 head....

Cheers

[cgarr]

I also added a slight chamfer to my heads when going from 95 to 98 with the 10.5/1 J&E's I also took the very sharp edges off the J&E valve pockets.