944 Turbo S Engine Rebuild Thread

[James0]

I like the look of that coil pack. The standard leads fit??

I picked up a VAG coil pack with built in igniters, which I bench tested and ran the loom at the same time as I was running a cable for something else.
I didn't go any further as I'd need to source suitable HT leads, (mine were quite new) plus remove the Igniters from my ECU. Just couldn't see the gain for the effort.

 

[blade7]

I don't know if there is much gain other than a stronger spark at high revs? I remember closing the spark plug gap years ago on dizzy cars, because supposedly the spark was compressed at higher boost levels.

 

[Eldavo]

I don’t know if the original leads fit - I must have about 16-20 of them if I need to modify anything or will just order some from Mr Retro Leads with the correct ends.

I looked at one of the VAG coil packs with built in igniters but there wasn’t much point as VEMS has 8 igniter outputs and a handful of logic level outputs too so i may as well run the wires from the igniter outputs and make it simpler.

I‘ve had spark blowout at higher boost levels before so it seemed a no brainer to go for a WS coil before turning the wick up a little bit more. One more step into the 20th century and no more fretting about whether I remembered to lock tight the rotor arm screw []

 

[Eldavo]

Coilpack terminals are different, I’m going to call Magnecor and see if I can get the correct ends to modify my KV85 ignition leads.

 

[Eldavo]

Spoke to Anthony aka Mr-Retro-Leads and he was very helpful, £16 later and the correct coilpack ends are en route to modify a set of Magnecor KV85 leads I already have. Although he’ll make you a custom set of leads in whatever length/colour/configuration you want for not much money, website is here (no affiliation other than good customer service received): https://mrretroleads.co.uk/

 

[Eldavo]

Ends turned up for the leads. Perfect fit, click and lock in securely. Will wait until later in the week when I get to my Indy’s as they have the correct crimping tool for them but that’s a cheap way of repurposing spare leads.


Came with the rubber boots too but I may just reuse the Magnecor ones already on the leads and just cut the length down to match.

 

[Eldavo]

Slight delay to proceedings as the machinist at Newman Cams had checked the clearance on the exhaust lobe not the intake lobe so it didn’t fit. Ken sorted it all out though, arranged collection, sorted it, kept me in the loop and had it back within a week.

So with that back, the cam tower was assembled and ready to fit . . . but it wouldn’t fit . . . at all.

2 mins of head scratching revealed that the mounting dowel had come out of the head and was stuck in the cam, wouldn’t have been an issue had we not ordered a new one and put it back in the head [] With that sorted it was plain sailing.

 

[Eldavo]

Belts on and tensioned, timing marks all present and correct - flywheel, both balance shafts and the cam wheel.


2 rotations by hand to make sure everything still lined up, recheck belt tension and then fit the front of the cam cover and the distributor, etc.

 

[Eldavo]

Left the plugs out, and put a booster pack on the battery, we’d backfilled the block with oil through the filter hole as well as filling it normally, there was plenty of assembly lube on everything too.


Fired up the laptop and uploaded the config for the TTV flywheel, fingers crossed that was sorted now it had been remachined.

So, fuel pump fuse out and spun it over to build oil pressure - holy moly that new Hi-Torque starter is a dream. But no oil pressure. Nothing. Also, no tech bounce - were things going that wrong already???

Stuck the kettle on and before it had finished boiling I was upside down in the passenger footwell plugging the binnacle connector back together. Coffee and a biscuit in hand, turned the key and we had 3 Bar oil pressure already.


Plugs back in and fuel pump fuse in - I have the solid state DME relay with fuel pump prime so a few clicks of the key back and forth saw my fuel pressure up at 3bar (I’d also learnt another lesson from previously and stuck 10 litres of fresh V-Power in).

Deep breath, turn key, barely 2 chugga chuggas and it burst into life until I shut it off 5 secs later. Now we had "proof of life” I could fill it with coolant, put the fans back in and get ready to break in the new camshaft (and engine) tomorrow. Started it again briefly to check a retensioned accessory belt as it squealed a bit first time around and I have never (and neither had the mechanics) seen any 944/968 start so quickly - the difference over the worn original starter is nothing short of phenomenal.

 

[Eldavo]

Last job of the day, car had earned a treat so . . .

 

[Diver944]

She lives! Fantastic [][][]

It wouldn't be right if there weren't a few last minute head scratching episodes.

On the cosmetic side it is all looking very pretty too, love the gold wrapped intercooler pipe [8D]

 

[Eldavo]

Thanks - don’t know if the gold tape does much but marginal gains innit.


The intake is outside of the engine bay so I figured anything that stopped the intake pipe being heated up in the engine bay would be beneficial, also did the side of the coolant tank as that’s pretty much a radiator when it’s up to temperature too. Didn’t do the post turbo charge pipe as my thinking was that was hot air so I wanted whatever cooling I could get from radiated heat before it went into the intercooler but wrapped the post intercooler pipe and did the bottom of the inlet manifold too.

 

[944Turbo]

Exciting!!!!! well done!

 

[Dan944t]

excellent mate!!!!

remember the first time i turnt the key on my full rebuild with race parts and custom cylinders ect,... and after it built oil preasure which seemed like a lifetime , but started on the second turn once spark was connected,..... what a bloody amaizing feeling ,..i remember it feeling like my child was born type of feeling!
even my wife started crying from seeing me do the entire lot on my own outside in my garden including putting engine in on my own ,....think she felt all my emotions !!!

great great feeling , well done ,..looking forward to hearing how it all turns out ????????

 

[Eldavo]

Ran like a bag of poo with a bad misfire and lugging under any load. One of the HT leads was showing open circuit so replaced that with one of the 20 others I have! Ran great then started bogging down and super-rich. Plugs out, cleaned them up, O2 wideband out and it was so caked in carbon it wouldn’t calibrate. Cleaned it up and recalibrated it, put everything back together and it still fired up but super rich still.


A bit more head scratching and I loaded up the old config file for the ECU, quickly changed the trigger settings for the TTV flywheel - the joys of a decent user interface and a Bluetooth connection between laptop and car. Fired up first time and ran smooth and sweet, quick sense check on the fuelling figures and then I backed it out into the yard and spent 15 mins breaking the camshaft lifters in - tweaked a few other things while I was at it, I now have an accurate oil temp sensor in the sump which displays on the laptop and the head unit as a digital gauge.


Only other issue is that in refitting the fans, the radiator had popped out of the fitting that holds it in place at the top and my nice red S-shaped silicon hose has now created some lovely pink dust where the fan has caught it. Will remove and inspect, replace if necessary.


After 10 mins of running, all the oil had burnt off the exhaust manifold and all was good in the world. Need to bleed the power steering and adjust the alternator belt tension, refit the top half of the belt cover and it’s off for MOT on Monday. Got an under-load break in procedure for the rings so if we take the scenic route to the MOT station then can maybe get that done on the way there and back

 

[924Srr27l]

Ran like a bag of poo with a bad misfire and lugging under any load. One of the HT leads was showing open circuit so replaced that with one of the 20 others I have! Ran great then started bogging down and super-rich. Plugs out, cleaned them up, O2 wideband out and it was so caked in carbon it wouldn’t calibrate. Cleaned it up and recalibrated it, put everything back together and it still fired up but super rich still.


A bit more head scratching and I loaded up the old config file for the ECU, quickly changed the trigger settings for the TTV flywheel - the joys of a decent user interface and a Bluetooth connection between laptop and car. Fired up first time and ran smooth and sweet, quick sense check on the fuelling figures and then I backed it out into the yard and spent 15 mins breaking the camshaft lifters in - tweaked a few other things while I was at it, I now have an accurate oil temp sensor in the sump which displays on the laptop and the head unit as a digital gauge.


Only other issue is that in refitting the fans, the radiator had popped out of the fitting that holds it in place at the top and my nice red S-shaped silicon hose has now created some lovely pink dust where the fan has caught it. Will remove and inspect, replace if necessary.


After 10 mins of running, all the oil had burnt off the exhaust manifold and all was good in the world. Need to bleed the power steering and adjust the alternator belt tension, refit the top half of the belt cover and it’s off for MOT on Monday. Got an under-load break in procedure for the rings so if we take the scenic route to the MOT station then can maybe get that done on the way there and back

God it's so stressful just reading your final hurdles! , it makes me still prefer the turnkey option ! I earn good money whilst a professional Engine builder / tuner etc...does all the work
I could like you of had a go myself but then my business and the work / income would suffer be much less, so as above it was more cost effective for me to give various people
to sort it, and then just call me when it's all ready!

I know you've not got a deadline for a rolling road run like I did, hence I had to (And wanted to!) do at least 500 mile before it was hitting the redline on the rollers...
So a trip from North wales to Lincolnshire an back in a day soon sorted this, but also LR told me to do as long runs as I can with it, not just 20-40 mins
But if possible 2+ hours long to really get some Heat in the lump.

And to Load the engine but not rev above 4000rpm, similar to how I used to run in 2 Stroke racing engines (Although they revved to 16,000!) where I did hoon
it from low rpm and speeds hard but short shifted, BUT Do NOT do this and blow it / blame me !

I just followed LR's instructions to the T also with the oil break in etc.. and she did grand on the rollers, the road for 2 years and then 3 Endurance races in constant anger all so far
with 100% Reliability

R

 

[Eldavo]

I don’t think an hour of clarting on is the end of the world for such a modified specialist build. Luckily I have plenty of holiday to take so a few afternoons off has been a welcome relief from the work laptop screen.

I have a specific piston ring bedding in procedure to follow which is somewhat different to your methodology - I’ll quietly crack on with it though as I’m sure you’ll tell me how I’m wrong and then a story about "this one time at bandcamp when you shared a tent with Mike and Dave Lindsey”

 

[924Srr27l]

I don’t think an hour of clarting on is the end of the world for such a modified specialist build. Luckily I have plenty of holiday to take so a few afternoons off has been a welcome relief from the work laptop screen.

I have a specific piston ring bedding in procedure to follow which is somewhat different to your methodology - I’ll quietly crack on with it though as I’m sure you’ll tell me how I’m wrong and then a story about "this one time at bandcamp when you shared a tent with Mike and Dave Lindsey”

Eh ? An Hour! I'm talking about the hundreds of hours you've put on this car!
bandcamp!?? eh.....Too many hours on the laptop! Remember last time you got snotty, the voodoo Doll starts get busy!

Quit while you ahead and let's see how the bird runs next week,.... month and year
This thread is titled Engine rebuild thread, lets hope it's for the last time!

R

 

[PSH]

Well done David, happy days ahead...not sure what your specific ring bed-in procedure is? but what Roger said is sound advice. You need heavy load, on and off the throttle and keep below 4k rpm. No long motorway driving at constant speeds for a few thousand miles at least. Change the oil within 1k miles, IIRC I changed mine at 500 miles and changed again before going to fully sythetic later.. can't remember how much later but I would guess it's in my build log.

have fun and enjoy...

Pete

 

[Eldavo]

Roger, how many times are we going to keep going round in circles? You are a laughing stock on every forum you’ve besmirched and on FB too. I got a message just this week about how you’d offered somebody who doesn’t even own a 944 an unsolicited copy of your "£30k build spreadsheet”.

I’d rather you didn’t comment on this thread again please. I wish you all the best with your build and your racing career, may it be long, relatively uneventful, and ultimately keep you busy.