2.2 race motor rebuild
 

I am about to rebuild my 2.2 for Tarmac rallying.

My plan is top obtain as much HP as possible with out having a motor that needs to rebuilt every other month. So I would like some input on the configuration.
The class rules require me to maintin the same injection and single plug ignition.

Motor 2.2S MFI
Boat tail case
Knife edge crank
JE Pistons 10.3.1
Nickies
S cams
opened up ports
SSI heat exchangers
Eurometirx 38mm throttle bodies
2.2S MFI Pump

Has anyone got any ideas on what sort of HP I should be looking at and also who has run a similiar combo

thanks in advance

Michael

From what starting point? The early (2.0) factory rally cars used a 2.0T heads with S cams. If you already have 2.2S heads, I wouldn't open them up any further. If you have 2.2T or E heads, you might want to consider keeping them as is (to save some cash) and smooth the mid-range some.

close to 190-200 hp

I have a very similar engine

Michael, I was under the impression that you were allowed Twin Plugs for LMS?

Mark
Sydney

Can you change the cam? Or will you be penalized with weight?

Mark,

Plan on running the car in SS.

Cam grinder cams can be changed what would you recommend.


Michael

I would use my dc60 grind, especially with 10.3-1 compression.
With your combination, the powerband would be 4500 to 7500.
At least 15+ hp more than the S cams.

Hey John I would like to thank you for your quick shipment of my cams and great technical assistance. Those are 2 things you do not find in the Porsche world. Thanks again!

Eric Hood

Your welcome Eric.

Michael, it might be worth checking on the legality of boat tailing and knife edging. My reading of the regs is that this is not on for SS. Might save you some aggro down the track...

Mark

Mark,

Checked the regs are they say you can remove metal not add.

I am trying to ensure the car is built to be above all reproach.

My view is that I am rebuilding the car from the ground up so I can incorporate all the necessary modifications whilst ensuring the car will have no problems in running in SS for Targa Tas and classic Adelaide, as well as being able to be used for group SC historic races.


Michael

Michael, here are the regs for SS engines from 2004 Classic Adelaide. I don't want to be a wet blanket but I can't see anything in here that would allow boat tailing or knife edging. Given the aggro caused to a number of Porsche guys in the past, I'd strongly reccommend getting a ruling to remain above reproach. Also, 10.3:1 ??? C/R.

QUOTE...

The original engine specification as supplied by the vehicle manufacturer for the make and model
concerned, must be employed. Mechanical modifications are forbidden except for the following:

(i) overboring is only permitted within the manufacturers normal specified reconditioning
tolerances (this is generally restricted to around 0.5mm increase in diameter).

(ii) pistons are free, however they must be dimensionally the same as original, except for the
diameter, which is only allowed to be varied as per (i) above.

(iii) reconditioning of other engine components within the manufacturers' specified tolerances
is permitted.

(iv) the original head may be modified by the removal of metal only. The valve sizes must
remain standard. The compression ratio must remain as standard.

(v) camshaft timing and lif t is free.

(vi) for rotary engines, the only allowable modification is "extended porting". In addition, the
exhaust port inserts must remain standard and in their normal place. "Bridgeporting" or
"peripheral porting" is not permitted.

(vii) the original ignition system must be retained save that 'pointless' distribution operation
may be substituted for breaker points. Freedom of mechanical and vacuum advance
mechanisms is allowed, as is freedom of ignition wires, spark plugs, etc.

(viii) turbochargers or superchargers, if fitted as original equipment, must remain standard, as
must the method of controlling boost or pressure. The amount of boost or pressure must
be standard as specified by the manufacturer.

(ix) the complete original induction system must be retained, without additions or deletions.
The components which control the quantity of fuel entering the combustion chamber may
be modified, provided that they do not have any influence over the quantity of air
admitted. Replacement air filter cartridges are permitted as long as they fit into the
original air cleaner(s). Additional air ducting is not permitted. Fuel pumps are free.

(x) the exhaust system is free past the point of entry into the first muffler. The exhaust pipe
must exit at the original point on the vehicle.

(xi) engine liquid cooling systems (ie water and oil) must remain as standard, although the
radiator may be replaced by one of the same size, but of greater thickness. The original
cooling fan(s) must be retained unaltered, but one additional electric fan may be added.
Thermostats may be removed.

(xii) air cooled engines must retain the standard system, although the speed ratio may be
changed.

(xiii) ancillary items such as starters, generators, etc., may be uprated, provided that the
original type is respected.

(xiv) clutches may be uprated only by the changing of springs, diaphragms or linings, however
the remainder of the clutch assembly must be original.

(xv) engine sumps may have internal baffling but the sump shape and capacity must be
standard.

END QUOTE...

Thats it........:(

Mark,

I see your point.

I note at point (iv) for heads metal is allowed to be removed.

Compression ratio well from my research if I was to remove metal from the head the CR would increase so I dont see a problem with that area.

Point (iv) may require some clarification as they say metal is allowed to be removed and then they say CR must remain as standard go figure the logic.

I n any event I am not super concerned about the CR in the motor or the Final HP as my plan is to build this car and run it for a considerable amount of time and events.

I have had my fill of having modified cars that need to be continually changed I would like to learn to drive this long hood at ten tenths on teh track and 7/10ths on tarmac rallies.

My experiences with rallies previously was not a pleasnt experience as the navigator caused me a bit of angst. He was to busy trying to get ***** faced at teh pub each night and I never could be sure that he would turn up the next day and or fail the breath test.

Michael

Michael,

My feeling is that whilst the time advantages are attractive for SS, it's just too restrictive. I feel that LMS provides enough scope to build a fun, reliable rally car without going crazy. I have a 2.7 (in a 914/6) giving about 220hp, really understressed power from 4000 to 7000rpm. The problem is the regs changed after I built the engine (aluminium cases) and I have to start over. I'll probably build a long stroke 2.5L but haven't made a final decision.

Quote: My experiences with rallies previously was not a pleasnt experience as the navigator caused me a bit of angst. He was to busy trying to get ***** faced at teh pub each night and I never could be sure that he would turn up the next day and or fail the breath test.

Bummer! I wonder what the penalty is for murdering your navigator?:D

I guess I've just been lucky thus far. I'm in preparation mode for Rally Tasmania next month.

Cheers,

Mark

Mark is your 914/6 car the one prepped by PR.

I think Ryan also got caught with the reg change on Alum cases and had to build a new motor. I heard he is doing it again.

Hence why I think SS is the way to go a low stressed engine and with the age of my car I dont get any headaches of wide tyres rubbing on teh bodywork and all that stuff.

I would really prefer to be runninf a 2.0S 69 911 however every one I looked at was a POS. so I bought this 2.2 which If at a later point I wanted to run in LMS I can easliy built an additional motor say 2.4or 2.5 short stroke for the rallies.

I suppose I don't want to go to the hassle of stuffing around with brake bias and different brakes I see that SS I can use genuine parts and not have to worry.

Michael

Michael,

Quote: Mark is your 914/6 car the one prepped by PR.

Yes, the yellow one.

Qoute: I think Ryan also got caught with the reg change on Alum cases and had to build a new motor. I heard he is doing it again.

Yes - dropped a valve in Adelaide :(

IMO, a 2.2S running in standard spec should be a good combination. The way I see it (and to get this thread back on its original track) is what can be done to a 2.2S within the regs above :confused:

A 2.2S is already well optimised. You might get higher compression by messing with deck heights etc but I doubt there's much in it as it's already 9.8:1

The valves and ports are already comparatively large - probably the biggest restriction on getting it to suck more air are the throttle body diameters which cannot be altered under (ix), although others with more knowledge than me might want to comment?

Cam profiles are probably the biggest item of potential gain - this list is your friend ;)

In the final analysis, you might get 190-195hp without going to the expense of boat-tailing, Nickies, knife-edging etc (which the gurus on this list consider pretty much worthless for most engines anyway).

Just MHO - best of luck with your project.

Mark
914/6 2.7

Mark,

Thanks for your input.

The reason I was going to use Nickies is two fold the first being my existing Pistons and Barrels/Cyclinders are shagged and secondly they are also 30% lighter.

As I have read and reread the rules I see that I am allowed a variance of some +/- 5% weight on the total car. If you allow that the cage will add 80+ kilos and then you need to save that same amount of weight somwhere else.

As I cannot use fibreglass panels weight becomes the enemy.

Michael

I've heard that the Nickies are a good product (I didn't mean put them in the 'worthless' basket with boat tailing etc) and if you need to replace your P&Cs and you see the value, then fair enough - but it's a lot of $$$ to save a few pounds...

80 KILO ROLL CAGE (175lb)? Did you find some left-over Sydney Harbour Bridge girders somewhere?:)

Cheers

Mark

Mark,

I talked to Bond roll cages and they said that a six point cage would end up approx 80Kg.

Do you think the cage should be lighter.

remember that there would be more tubing in a 911 thana 914/6 (bigger cabin)


Michael

Michael,

Quote: Do you think the cage should be lighter.

Don't know - it just sounds excessive. Mine is made from chrome-molly and was built to stiffen the chassis in addition to its safety role so is braced forward and aft into the engine bay in several places. I wouldnt' have thought there would be much more tubing required in a 911 - but what do I know? FWIW mine weighs 46KG and I thought that was OTT.

Mark

Mark is your cage all chrome molly??

Would that be the reason why it only weighed 46kg

Michael

Michael,

Yes, the whole cage is Chrome Molly built by PRT. Many $$$ and several CAD designs before we got an engineer's sign-off that would pass CAMS approval. I doubt there is a better cage in a 914/6 anywhere in the world...

Ryan had his built by Bonds I think - you might want to ask him how much it weighs....

Andrew Kirkbride (AMK) had his built by PRT (also Chrome Molly I think?). You could ask him for details...

Cheers,

Mark

Your cylinder heads have ports so large that they will support much more power than you can ever realize. So just make sure your ports are matched and all the flashing is gone. The Power is in the following areas:
1. Compression- do everything you can to increase the compression, as its free hp.
2. Cam- even the stock T cam can make 160Hp if properly timed, other cams can make up to 200HP at fairly high RPM. BUT if you don't have piston squirters and extra oil coolers, don't do it.
3. balancing and shot peening are free, do it.
4. have everything bolted togather for a final flow test, should flow almost the same as just bare heads if everything is good.
5. Dyno- jet it on a dyno, do it right.

Real power is only obtained using a dyno, no other, reasonable, way.

Snowman,

Thanks for your input.

I see that one of the areas which I should be able to gain some HP is by fine tuning the advance curve.(trial and error) as well as the MFI

Michael

Walko, the weight savings of the Nickies are just a bonus. Especially in the case of the 2.2, the Nickies will reduce your head temperatures drastically, 100-150F, and that's good for 10-15% more horsepower, torque, and fuel economy, over the stock cylinders. Oil temps should drop by 20F or so. You might even be able to afford reducing your fan speed and gain a few more horses that way too, with the extra cooling of course :-)

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance

Mark, could you post some pics of your roll bar?

Walko,

Don't expect anything out the advance curve for a race car. Why? because most all advance curves are maxed out by about 3000 RPM and most race cars never run that low.

The max advance is the only thing you have to work with. About 32 degrees up to 36 degrees or so.

Charles,

Thanks for your input.

Michael

Snowman,

You must remember that this car will be used for Tarmac Rallies as well as Circuit racing and there are quite some first and second gear corners. So it is possible that the revs may go under 3000 in first and second gear corners.

Michael

Michael,

Your issue with an engine that can stay together for a long time has to do with RPM. An engine you shift at 7300 (or even 7500) will last a long time if built properly. If you turn it 8000 – 8500 all the time then I like a 25 hour rebuild schedule. The maintenance overhauls are SO much less expensive than some disastrous malfunction.


Mark, I don’t consider boat tailing the case, knife edging the crank, mooning the cylinder spigots, and more to not be worthwhile for a high rev engine – 7000 RPM. This significantly reduces pumping losses inside the crankcase.

Michael’s reasons for using Nikasil cylinders are just fine but it also includes better ring sealing and performance. Nickes = horsepower.

Anything you can legally do to raise the compression ratio makes more power. You just need suitable high octane fuel and keep the cylinders and heads cool.

One of the things I noticed in the rules is you ability to use a higher ratio fan drive. That has a net HP gain and helps the engine longevity by keeping the cylinders and heads cool.

Do the rules allow the “Rubbermaid Solution”? Search on this Forum.

If you can legally use twin plugs – go for it!

With camgrinder’s hotter cams, perhaps you can use even higher CR – say 11.5:1?


I’ll go re-read the rules posted. There is usually much to be gained.

Best,
Grady

Grady,

Thanks for your input.

To stay in SS you can't run dual plug.

When you say maintenance overhauls every 25 hours what would you put into the motor.

My logic would be to ensure that oil and filters were done every 10 hours. surely turning a higher RPM would not dramactically decrease the life span of the bearings and rings. I am no expert so if some one can advise why the shorter life tim eon higher revving motors I would appreciate it.

Michael

Grady,

(Quote) I don’t consider boat tailing the case, knife edging the crank, mooning the cylinder spigots, and more to not be worthwhile for a high rev engine – 7000 RPM. This significantly reduces pumping losses inside the crankcase.

I agree - for a race engine that will see sustained high revs it is logical, but others seem to be rather sceptical. Done properly, the worst that can happen is to lighten your wallet :( .

The issue that Michael faces (and others of us for that matter) is optimizing his setup for multiple use (Tarmac Rallys and club sprints) within a sensible budget which includes not only the engine, but transmission ratios, suspension set up and so on. A car optimised for the track can be a complete dog in a tarmac rally. As we all know, making the last 10 or 20 HP can be a very expensive excersize, money which may be better spent elswhere. In any event, the Standard Specification (SS) category deliberately restricts modifications by several catch-all clauses. I would be amazed if anyone here could conjour up much more than 200HP from a 2.2 given these regs. I am however allways prepared to be amazed :)

Don,

Being a professional technologist but a personal Luddite, I am sans the digital camera thingy. However, here is a picure of my cage prior to being installed in the car. If this doesn't work, you can find it at www.prtechnology.com.au, click on Performance Products, scroll down to Roll Cages and click on the picture. Mine is the first cage displayed in the upper left of this page. The cage forward of the main hoop is removeable. Being 6'2", we needed to make as much room as possible, so removed the section of bulhead between the seats, welded in the main hoop and then welded the section of bulhead back in around the cage cross-bar. I now have good leg room. Not shown are the rear facing bars which are welded back to the chassis below the shock mounts, necessary to pass our CAMS engineersing requirements but has the added benefit of stiffening the whole chassis by a huge amount.

http://forums.pelicanparts.com/uploa...1106530135.jpg

Cheers,

Mark Lamberton

That extra 1500 RPM is the most expensive thing you can do to an engine. Wear goes up exponentially along with cost. An engine that can live for many years at 7000 RPM might only last minutes at 8000 RPM . With lots and lots of extra bucks the minutes can be made into hours. For competative racing you must be on the edge to win, if you are not you will not win. What that means is the person who pushes everything to the point where it breaks one second after the race ends is the one who wins. Add to that skill and you have only the best driving things, that are just about to break, winning. Then there is the rest of us.