997.1 Engine rebuild

[ochayethen00]

Hi all I could do with some pointers on my 997.1 C2S engine rebuild.

I've got bore score on cylinders 4 & 6 and the engine has almost 140k miles on it. The engine is out and car has had a really good tidy up with lots of parts replaced. Hopefully in the next month or so I'll get started stripping down the engine.

The plan is to send the block to Hartech to do all 6 liners.

Pistons not to sure yet, maybe Hartech or Porsche OPC?

Any rebuild kits that are worth buying? Gasket set design911?

Any good tooling that's essential?

Any other mods worth doing whilst in there?

I'll be replacing the oil seperator, tandem pump, chains, coil packs etc

Would having the injectors cleaned/checked be a good idea or replacement after 140k miles?

 

[MisterCorn]

I'd just have a chat with Grant at Hartech.

MC

 

[IMI A]

Worth a watch.

 

[infrasilver]

You'll be wanting to change as much as you can while in there, all chains, guides etc and obviously larger IMS if you can, main and big end bearings. Standard pistons can be re-coated by Hartech, depending on condition, but it may be worth considering a capacity increase for the extra it costs and if you are doing all the rebuild work you will offset that against your own free labour.

There are special tools for putting the engine back together again and for timing it up. I made my own assembly tools but use the correct kit for timing it.

On my most recent rebuild I found that Autodoc and Porsche were cheapest for parts. I did a spreadsheet by comparing part prices for each item I needed from all the part suppliers.

Be mindful when you first crack the engine apart there is still around 1 litre of oil knocking about in there and goes everywhere if you don't have something to catch it in.

Keep us posted on progress, there is enough knowledge on here to guide you through the process.

 

[ochayethen00]

Thanks I spoke to Baz a couple of months ago to get some ideas on process and cost so I'll give them a ring again once I've looked into things a bit more.

Thanks for the YouTube link. I've watched that before and tried to find the episode again but couldn't so thats really handy.

Thanks infrasilver I've read most of the pages on your rebuild, really handy. It was a few months ago now, I'll go and read through it again actually. Good shout about the oil still in the block.

Has anyone had their block and heads soda blasted/ultrasonic cleaned? Would like to get the engine looking new on the outside as I've done quite a lot of work on the rest of the car.

 

[Steve Wright]

Hartech four litre ?

 

[ochayethen00]

The four litre did cross my mind, not sure it's worth the extra hassle. Happy to be convinced otherwise though.

 

[paul_mck]

4.1 now no?

 

[Robertb]

Does the 997 have the same stupid brake line that goes over the 'box? I'd check that if I had the engine out...

 

[ochayethen00]

It sure does and I've picked up a new OPC one ready to fit once I've sorted a little corrosion that was behind it. Don't fancy doing that one with the box or engine in! Also picked up some new large coolant lines, they were not leaking but were very corroded at the collars.

 

[JonnieD]

The four litre did cross my mind, not sure it's worth the extra hassle. Happy to be convinced otherwise though.

If you're doing the work apart from the liners and machining, I don't see how an oversized rebuild would be extra hassle?

My read of the Hartech ones, is that its a bore change only, so the machining on the old blocks is the same, with oversized bore liners, and obviously a full set of new pistons. You were talking about replacing those anyway, so surely there's little difference in the build process.

I don't think Hartech are doing any work on the heads are they on their oversized builds?

 

[ochayethen00]

I think for the 4.0 Hartech would prefer the car there and carry out the entire build and mapping. Also I'm in Aberdeen so trips to them isn't exactly convenient. Not sure there are big gains to be had from going to 4.0 from 3.8?

 

[bazhart]

There are what those that have received them call huge benefits in the 4.1, more torque, more power, easy overtake without changing down, better fuel economy and lower emissions. Similar results with the 3.7 and 3.6 to 3.9.

The re-mapping is to clean up some very minor areas that most would not notice.

Last weekend the 4.1 race car was only finished the night before practice for the first venture into endurance racing in the National Championship at Silverstone - no time to re-map so drove under power up for the first time at the circuit but won its class - due for re-map before the next event - so it isn't essential but makes a better job overall.

It is more expensive because you need new pistons and extra work on the crankcases - but if you are capable of doing it yourself you are already making savings there.

There are more details available free from [email protected]

Whatever and with whomever you choose - good luck with your rebuild.

Baz

 

[ochayethen00]

Hi Baz thanks for clearing that up, great to clarify the differences and it clearly does make a difference going to 4.1

I'll be getting the Hartech liners done 100%. Still lots of research to do for everything else. I'll be giving you a call once I've done some more research. That way I won't be phoning you every day with questions....hopefully

 

[tom_nieto]

Baz - encouraging results with the 4.1 conversion! So I can prepare my wallet for the eventual shock, how much does this cost to do on a 3.8? I assume it doesn't matter how many liners are scored and how the pistons look as you need new ones anyway?

What power and torque figures are you getting with the conversion?