Cheeksyboy

9M Technic, 9M Panelcraft, 9M Racing, 9M Parts and


introducing

9M Dictionary Corner

NineMeister

Don't shoot the messenger.

boxsey911

Frank, it looks a nice shopping list and it's a nice topic for everyone to discuss but I can't help thinking that you're going about it the wrong way. Surely, the engine builder should be having a big input in to the component parts of the build? You'll want the builder to stand by the engine after it's built. I can only see them doing that if they're the ones that spec the engine (in consultation with yourself) and source the parts. If you source parts yourself and any of them fail then things could get very messy trying to sort them out. Just my 2p.

Porsche964FP

Oh absolutely, I don't dream to be the one who finalises the spec or sources parts by any stretch of the imagination. I'm just trying to educate myself as much as possible - out of pleasure and so I have an understanding of choices made when builder is finally chosen.

Cheeksyboy

I was just pulling your leg... I want to disagree with you, but don't seem to be able to....

.....and I agree with Steve. It's nice to play with specifications of parts when you're dreaming your ultimate spec, but unless you've got the funds (which I don't) to go testing you're surely best to go with what someone else has tried and proven and copy that, or use that as your foundation.

I seem to remember saying this in thread #27

"...and then talk to your chosen engine builder and, like Kai has done, make a decision not just about your engine, but also how and what you use the car for......"

Makes perfect sense......

KaiB

Ya'll are on the money here.

Far beyond the build and the components it takes to do one are the driver, the total car, the tracks or intended use and the builder. As Colin drives home, it's synergy.

It's all one large system which begins at the driver's eyes and ends at the tire contact patch.

Not to bogart this interesting thread, but my car was built for the classes I race, on the tracks I run, with my competetion in mind - and a long eye towards my driving style.

Porsche964FP

...

Porsche964FP

No replies?

I'd like some feedback on combining JE pistons with Mahle cylinders? I'm hearing conflicting reports on this combination, some say the different expansion rates are an issue (slapping), others say not at all with right rings etc?

EDIT: Furthermore any feedback on LN Engineering and Nickies?

Also valves, some say 993 valves are the way to go... Others say the difference is negligible because the exhaust outlet cant be changed without braking the plateing or can it? If it can is this a huge expense for very little change? Remember this is in combination with ITBs.

EDIT: I read that the linkages on PMOs are better than those on Jenvey items?

Thanks gents, just continuing research...

Hi Kai,

I've said it before I'll say it again - car is looking so awesome, congrats.

If I may ask, what brand P&Cs are you using?

NineMeister

No doubt Frank that you will see a similar family of power & torque curves from your other vendors, however for the sake of clarity amongst other things these dyno curves should clearly show why you would probably not select ITB's on a sub-7000rpm 964 engine, the real difference between 3.6 & 3.75 litre engines, the benefit of a set of headers and finally what happens when you try a little harder than the norm (no offence intended to any 911 engine builders called Norman ).

Brown = standard 964RS engine
Pink = 9m Motec+1 (motec with ported heads and 9m sport cams) on 3.6 964RS (~£10k)
Green = 9m Motec+2, which is the same as +1 but with 3.75 litre upgrade (~£14k)
Red = 9m Motec+2 with headers (~£18k)
Blue = 9m 3.75 litre Clubsport Race engine (Motec, 3.75 litre, billet heads, race cams, ITB, headers, etc) (~£25k)

As you can see, the best bang-for-buck for a road car is definitely the 9m Motec+1 upgrade, as intimated in my previous posts.

Note:
all prices exclude VAT
9m M84 Motec conversion costs £4300 installed & mapped (ecu on its own is £1500).
Additional engine repair costs are likely to be encountered (valve guide replacement, plug leads, tinware, chain ramps, etc...)

Johnny G Pipe

Its really nice to see the direct comparisons, thanks Colin. Impressive differences..
Any chance you'd be prepared to put a ballpark cost next to each option, of course bearing in mind the +/- factor that comes from additional bits and pieces that crop up..?

KaiB

Frank, the engine is essentially stock.

NineMeister

Ballpark prices added to original post.

Geoffrey

Frank,

The Mahle Piston is made from High Silicon content aluminum whereas most (all?) aftermarket pistons use 2618 aluminum which as mentioned has a different expansion rate and therefore different clearances are required. Personally, I dislike JE pistons, although recently I'm aware they have addressed some of the previous issues with their Porsche blank. To be fair to JE, many, many years ago, they did have to run wide clearance which resulted in piston slap. I haven't seen that lately. In addition, until very recently, they did not have a Porsche specific blank so the piston was heavy and could not be optimized properly. I don't know about the new blanks. In the past, when tuning an engine, I could always tell if it had JE pistons becuase it required more ignition timing due to the dome inefficiencies. We've gone even further on the piston designs by digitizing the cylinder head so the piston intruder can be optimized, as well as running some very nice, expensive piston rings in .7mm thickness.

I have and am currently running Nickies on my race engine and like the cylinders a lot. On my 103mm bore, I do not even run cylinder head gaskets (think < 91 964 engines).

I think what you are asking about is what valve sizes. This will depend on the cylinder head. We run 8mm valve stems in various sizes, depending on the port work. Again, you need to consider the entire package. We do not run stock valves as they are heavy and the profile of the valve does not provide for the best valve out there. We use aftermarket custom valves and in some cases with the 9M cylinder heads and Racetek high lift camshaft, we run the 9M valves with raised keepers.

The PMO ITBs are a good value, but they have different size runners and the throttle bodies have a common shaft. This means that the outer two cylinders work differently than the center cylinders due to the different length of the manifold runners. The solid linkage, while easy, can bind as the engine heats up and at times can be problematic. The Jenvey are nice, simple, and the linkages allow for finite adjustment, but you need to know what you are doing to use them.

Not to be a *****, but I've seen this approach to engine building before - build via a list of Internet parts, and it generally does not work out well. You need to find an engine builder and work with them because there are a number of different ways to accomplish similar goals.

Johnny G Pipe

Thanks! Quietly calculating for the future...

The Stig

Now the trick will be getting the North American price equivalent!