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Carrera 3.2 to 3.4 engine rebuild

Sure modern ECUs offer lots of flexibilty on inputs and outputs, better scan rates and faster processing, they can be used with traction control, throttle bodies, set up different maps for race fuel etc etc but in an old Porsche is this necessary or indeed what you want? At the end of the day you want to tune the timing and fueling to optimise the engine you've built. Motronic will cover those bases quite easily. Last guy I know who built a 3.4 managed near 300hp after Wayne had done his thing.
 
One other potential advantage of a new ecu (done well) is reliability, the motronic units whilst surprisingly reliable given the age are not getting any younger!
Tony
 
Ras62 and 944Turbo, you both make very valid points, thanks for the input - so decision time me thinks.

Ok, she's now initially booked in with Wayne early September, it will mean breaking into my new (2016) CS Motronic ECU but at least I'll have a car running the best it can post the rebuild.

This will then enable me to pick Wayne's brain as whether a new ECU is a worthy upgrade and then do further research as to which route if any to take.

Cheers

 
In the interim I have just purchased 6 new injectors so as not to leave anything to chance
 
So as an interim measure a new set of injectors fitted, sounds and runs even smoother through all the rev rang - safe to say new injectors should be factored into a rebuild.
Car booked in to Chipwizards for dyno tune, lets see what we can achieve, this will also give me more time in investigate ECU upgrades which I may do in near future.

 
Work in progress improving the dream ..... I can feel a long term running report. Be good to share with other 3,2 owners here .... it's not a common upgrade and seems to give varying results and BHP Torque results ... ??
 
I went for a little 50 mile spirited blast last night and I must admit since I've fitted the new injectors I've noticed a considerable increase in low and mid range urge.
Coming out of a couple of tight corner I changed down, planted the throttle and was surprised how much increased thrust (being pushed back into the seat) I'm now feeling.
Maybe it's just my imagination, but it felt very good.
 
OK, OCD kicking in, mileage now 985, 15 miles to the garage where she booked in tomorrow for her 1k big service.

Booked into Chipwizard on the 6th September,


 
The curse of the 3.4 strikes again!
As you know the car has run faultlessly during its 1k miles run in and yesterday’s 200 miles up to Chipwizards no different.
So she goes onto the dyno and the first 20 minutes Wayne is mapping in the anti stall and idle settings, no power runs, just a blips on the gas here and there. Suddenly she starts running very rough and the cause seems to be from the right bank. So we immediately switch off and investigate. Off the rocker covers comes and visually nothing seems to be amiss, Wayne tests the rockers with his hands and finds the middle one has quite a bit of movement.
So off come the injectors, bore scope in and on examination it would appear that my valve seat on number 5 had become dislodged
This is a first that Wayne has seen or heard of, likewise when we told Steve.
The car was flat bedded back to Jaz for further investigation.

To speed up the build process a set of spare heads were sent away to be refurbed and the original seats were used. Am I just unlucky or could there have been an inherent issue with those head?

I must have been bad in a prior life, ??
 
Engine dropped this week details to follow.

In the interim my original heads have been sent off for new seats and a full refurb!

 
The engine has now been split and the original diagnosis of a dropped valve seat was correct - on an IB this seems to be unheard of!

To speed up the original build process a set of spare heads were sent away to be refurbed and the original seats were used. Am I just bloody unlucky or could there have been an inherent issue with those head, who knows, anyway my original heads have been sent away for new seats and a full refurb.

The piston had a slight ding in it, so awaiting a new JE piston from the US, and new value has been ordered, there is no other visible damage. The piston Rod will be checked over and new shells fitted as a precautionary measure.

With any luck she’ll be back on the road shortly.
 
No Pain no gain unfortunately ..... keep up the good work, using original heads makes a whole lot of sense.
 
What lwt clutch are you using beaky? Patrick motorsport or ?
i have a modded 3.2 coming and looking for g50 options to lighten clutch but not much around although 930T is same diameter

 
Maybe give Autofarm a shout .... there is a 3,2 for sale they rebuilt from the crank to a 3.6 etc ..... look very impressive .....
 
OK, new piston has arrived from the US, so hopefully she'll be back on the road within the next two weeks.

Boydyrs,
if you PM me your email I can send you a copy of my invoice with all the associated part numbers.

At the same time as I did the clutch I also fitted a KAAZ LSD, again all details on the invoice.
 

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