Help to choose a 911 2.2, from the E version to S mod

[alexARC]

Hi

I'm thinking to buy a 2.2E (in fact i'going to see one in 2 weeks).
I'm planning to use this car for a mix of road/trackday.

I have a fairly good idea of what must be done on the chassis.
Need a set of front S calipers too.

I might need a bit of help for the engine though:
I want something close to a S spec, keeping the price "reasonnable":
1. set of "S" HC pistons (JE) and Solex cam (+crankshaft balance)
2. MFI pump S setting and S ignition curve
3. porting head to 36mm and throttle body (can i bore out the original 2.2E TB?)

Questions are:
-what thing i have missed?
-Should all these modifications must be done at the same time or could i start with 1 and then 2 and 3 later?

Cheers
Alex

[Flieger]

It is best to do them all at once.

The cam will need more air which requires bigger ports and throttle bodies to not drop off at high RPM. You can bore out the T stacks, this is what I have. This means you can burn more fuel. See Jeff Higgins' thread "MFI Pump: Open Heart Surgery" for the procedure to richen the mixture as much as you need to get your car to run. You can make a T spec MFI injection pump push as much fuel as an S or RS 2.7 but it is a bit of a stretch and the space cam is not exactly correct but you should not notice a difference in full throttle power. This can save money doing it yourself.

To run the more aggressive cam, you need to be sure your pistons will not hit the valves. This may mean new pistons with relief cuts to clear the valves especially with high domes for high compression ratios. If you have CIS pistons, you may need new ones. Make sure you can run your fuel with the compression ratio you chose. Twin plug is an easy upgrade that is very benefitial to ease detonation.

It is easiest to do all this at once so as not to tear down the engine multiple times.

Provided you have adequate valve/piston clearance, you can do cam, then ports, then pistons.

For brakes, especially S calipers, go to Eric Shea at PMB performance. His username here is Eric_Shea.

Have fun with the car

[Flieger]

If you have a mechanical mindset and are good at working on your own car, read this:

MFI Pump - Open Heart Surgery

Then see this: Putting My 3.0 MFI Motor Back Together

His motor detonated due to JE pistons being much higher compression than ordered. He also reduced backpressure and it was a cool day. He ran too lean and without twin plug ignition.

The thread where he shows the damage has been lost during software updates on the BBS apparently.

[fbarrett]

Alex:

Unless the engine is trashed now, I suggest driving the car for a while before you jump in with engine modifications. Not only will this give you an idea of what the engine is like, it will also allow you to evaluate the rest of the car (suspension, brakes, injection, everything) and see what else needs attention.

A 2.2 E is one sweet car, faster than an equivalent S out of anything but high-speed corners. I had one for years, ran it in many time trials and autocrosses, club raced it a few times, and I had no trouble with stock 2.2 Ss. Only a good 2.4S could give me a hard time. I sure regret selling it back in 2002; the car is now owned by rexav8r, but if he ever wants to sell it, I have first right of refusal.

When the injection is right, there's no smoother engine. If the pump needs work, send it to Gus Pfister at Pacific Fuel Injection in South San Francisco.

[alexARC]

Cheers Guys for your advices.

You are right Frank, that's what i want to do.
I start with the chassis because i think it's dangerous to bring a forty years old car on a track without any serious chassis check-up. I'll probably check simple things like gear shifter mechanism as well (coupler, bushing... because i know they can really make gear shifting better for cheap money).

For the engine, just a Dansk race exhaust and a K&N headers instead of this big black air filter box (could it decrease the perf?). I like a nice engine sound

I'm just worried about the front Boge suspension on the E (lack of torsion bar). Is it simple to replace by a normal bilstein setup (you need the full bilstein strut assembly?)

[BK911]

Frank's advice was awesome. If I could add one thing..

When you decide to modify the engine, keep it at E spec and put in a 2.4 crank and rods. You will have a high compression 2.4E that will run awesome from idle to redline.

[alexARC]

I had few conversations with people having owned both 2.2 and 2.4. The higher stroke change the engine response (more torquey whereas the 2.2 is a high revver).
I really like engine which must be revved to get the best out of them (and the sound is great).
But i don't know yet.

The other thing is to keep the car complient with FIA group 3 regulation (which required more or less a standard S spec +roll cage, seats, extinguisher).

[Flieger]

I agree with the chassis mods first. These are wasier and make the car feel much better. You can do a lot yourself and you will feel great with the payoff.

You will need the whole Bilstein strut assembly and the torsion bar. The Bilsteins are different and incompatable with Koni or Boge (orsion bar car) struts.

[Scott Clarke]

Careful with the exhaust and the air cleaner modifications. You will likely go backwards, performance wise, although you will make a lot of great sounds!

[alexARC]

Interesting Scott.

I'm surprised the modification to the air cleaner can drecrease the performance.

[Scott Clarke]

Alex-
Porsche doesn't do anything that isn't optimized for performance. It is very difficult to improve on the original equipment. The stock airbox is a Helmholtz resonator that boosts mid-range power with only a VERY slight reduction of top end power.

In a similar fashion, the stock muffler is very good with MFI. when I purchased my car it had a two in, four out Abarth muffler. It sounded great, but was too loud. I replaced it with a stock unit. I did measured acceleration tests before and after, and discovered that the stock muffler was much quieter, and produced measurably improved acceleration times.

All that said, I do have PMO/K & N twn air filters on my MFI now. You can't beat the sound or the look.

[alexARC]

I think I'll go for few less hp and a nice sound.
I'll do th exhaust first and i'll see if i'm happy enough.

[jluetjen]

Here's my $0.02 against your list. My thoughts in blue.

I'm thinking to buy a 2.2E (in fact i'going to see one in 2 weeks). Great choice!
I'm planning to use this car for a mix of road/trackday.

I have a fairly good idea of what must be done on the chassis.
Need a set of front S calipers too. Check the car, it may already have them. I think that the E's already came with the "S" calipers. The early E's came with the Boge hydropneumatic front struts -- most of which have been replaced with S style struts (which were drop-in replacements) by now. For example my '69E has S calipers on it with the replacement struts. Yes, they're slightly lighter, but the iron calipers are stiffer which might give a marginally stiffer peddle (all other things being equal.

I might need a bit of help for the engine though:
I want something close to a S spec, keeping the price "reasonnable":
1. set of "S" HC pistons (JE) and Solex cam (+crankshaft balance). Given the current price of gas, you might want to spec the car with something that won't be so octane intolerant. Using S pistons with with non-S cams will result in a static CR higher then an S's since the valves close sooner on the compression stroke. This means that you'll need to retard the ignition, which will cause extra heat and still leave the car close to pinging. Iti might be a better idea to keep the E pistons if you go with the Solex cams, or else use S cams with the S pistons. My car has S pistons and E cams and I've had to retard the ignition from stock to keep it from pinging on 93 octane.
2. MFI pump S setting and S ignition curve For a solex cam, you may not even need to rebuild the pump to S specs, you should be able to get it pretty close with the adjustments. Or you can spend the extra money.
3. porting head to 36mm and throttle body (can i bore out the original 2.2E TB?) With Solex cams, you most likely won't gain much below the highest couple of hundred RPM in the rev range by porting the heads. A 2.2E at peak RPM is running an intake velocity of about 98 m/s, while the 2.4's (same size ports in the head) went up as high as 100 m/s. Keeping the ports at the stock size should keep the engine meaty in the 2000-4000 RPM range, which you'd lose by opening up the ports. A stock S only out-performs an E above 5000 RPM. By using a Solex cam, that number may shift as high as 5500 RPM. Since this won't be a race car, I'd save the money and skip porting the heads.

[alexARC]

Good advice again.

Yes, ive read about the S calipers... That would be a nice surprise.
I need them to get the FIA group 3 certificate: the 2.0S, 2.2S and not the 2.4S/2.7RS...

For the engine mod., that's sound good (for my wallet
S flywheel, S pistons, Solex cams, normal head and TB, we can try that.
And good balance for the crankshaft.

[alexARC]

Next saturday, I'll see the car.

Apparently, there is a front anti roll-bar so the struts have been upgraded?

[alexARC]

Here's a photo of the front suspension



Bilstein?

[Flieger]

Looks like konis.

Here's mine:

[Flieger]

This may be a better photo to show the original Koni:

[johntyboy]

Hi

I have a 2.2E that I have rebuilt, I have used S barrels and pistons but retained the E cam, I also ported the heads to S spec 36mm and the throttle bodies to 36mm, the car has been set up on a rolling road and has 177BHP and 212NM of torque, it runs very well and still pulls like a train from low revs. Have a look at this thread for more info, it might be of interest to you.

http://www.ddk-online.com/phpBB2/viewtopic.php?t=17139









Kind Regards John

[Flieger]

What kind of coating is that on the fan? It looks like the factory coating on magnesium bits on the 917. Is it a nitriding?

Edit: I just read that you think it is a chromate finish. It looks like normal metal in the later photos of assembly but looks very dark like nitriding in the first photos. Interesting. How has the finish held up? Very well, I imagine.