Fonz0

Any thoughts on buying a 1987-89 911 that has had the top end redone and upgraded to 3.4L versus an all original 3.2L?

Ed Hughes

Depends on parts used, etc. Some may use JE pistons and Nickies (or similar) for the cylimders. Some early combos of these exhibit a lot of piston slap when cold, but I think later iterations of metalurgy/compatability have improved.

Mahles would be more typical of OE parts, and were somewhat of a common upgrade when they were more affordable. I built a 3.4L with Mahles, in the high compression version.

These are all plug and play, and would not require machining of the case.

So, now the discussion on ignition comes up. I'd be hesitant to chip such a motor, as the 98mm dia pistons start to stretch the reach of one sparkplug, and detonation starts to be a concern. 93 octane would be good prevention against that. Any timing mods by reprogramming the chip, would best be accompanied by twin-plugging.

Of course, high compression would neccesitate twin plugging sooner. Then, there is the "who rebuilt it" factor, and what else was done.

Any more details on what all was done.

salukijac

My 87 has JE (9.9.1) pistons and Mahle Cylinders increased from 3.2 to 3.4. 964 grind on cams. The rebuild was 35K (2005) miles ago. Prior to the rebuild: Max Power 200.9, Max Torque 183.5. After the rebuild: Max Power 223.1, Max Torque 200.6.

tlarocque

Like Ed said. "If" it was done right it wasn't a cheap rebuild. I would get as much info on the rebuild as possible.

I wish I would have rebuilt my 3.2 to a 3.4. At the time I was considering swapping in a 3.6 but I decided the car was nice enough to try to keep original and that's what I did.

g-50cab

my old 3.2 to 3.4 was 244 at the wheels and pulled like a train.

Engine Rebuilt top to bottom at 57,000 (6/20/2005) 3.4 mahle 9.8 to one jugs
~ 1MM taken out of pistons for valve pockets
Single plug
Magnecor Wires
Extrude hone intake
993ss cams (Dougherty Racing Cams)
ARP rod bolts
Supertech Head Studs
Enlarged throttle body
Competition springs and retainers (EBS)
New reference sensors
New CHT sensor
New fastening hardware
New rocker shafts
New RSR Rocker Shaft Seals
New teflon lined Carrera fuel line
New Carrera tensioner lines
New oil sensor
993 Flipped Flange Heat Exchangers
MK 993 Bischof flange muffler
Steve Wong custom chip to pull it all together
Dyno tested on Dynojet 248c - adjusted to 244.3 RWHP - so 287 hp at the flywheel corrected. Nice flat torque curve

UberXY

My 84 was upgraded to 3.4 and some cams and electronics by Andial 10 years ago, and it wasn't cheap. Runs great.

Turn3 Autosport

It the only change was displacement then expect an increase around the same percentage difference. Lots of folks did that when they discovered worn P/C sets as it costs the same to stay 3.2 as it does to move to 3.4. We built a few like that, one with a set of P/C we got from Jeremy (g-50cab)!

We also built a cammed 10.5:1 3.4 with twin plugs and ITB's, it made 275rwp and around 250rwt. It was a rocket.

Cheers