2.0 rebuild ?
 

I am about to go racing and need to rebuild the 69E MFI motor.

I need some input as to the best way to increase HP without increasing capacity(class rules)

My plan was
1 Higher CR
2 RSR sprint cams/ GE80
3 Shorter ratios in the G/box
4 Carillio rods
5 headers
6 Twin Plug
7 piston squirters??
8 TI valve spring retainers etc
9 Rebuild MFI pump and stacks to "S" specs


Does any one have any further ideas.

car will only be used on teh track and is already as light as I can get it.

Michael

The RSR sprint or GE80 cams might be too much for your 2.0 litre.
If you get as high as 11.5-1 the RSR cams can start making power in the 6200 range and up , the GE 80 about 6000 and up. Depending on where you race, your gearing etc, you might be better off with a GE60 style cam. With the same compresion the engine will make power around 5000 or 5200 rpms and up. If you have some slow speed corners where you race the bigger cams will force you to down shift more.
The GE60 style cam will be like night and day from your E cams.

John,

thanks for that I planned on having a very short box for the technical tracks and a bit longer ratios for teh HP tracks ie the ones with really long straights.

I was hoping to allow it to rev to 8K or more

Michael

Ah ok, if your looking for up to 8000+ rpms go with the 80 profile.

Walko,

GE80 or another 906 derived cam, twin plugged + ported 69 S heads, Weber/PMO 46's, Ti valve train, IMHO not Carillos but Pauters, old style steel studs or ARP's, piston squirters, boattailed case, knife edged crank, turbo or better oil pump with bypass mod. Pistons at 12.5 to 1 or 13.5 to 1 (Cosworth, JE's or?). I use Electromotive for the ignition but you could do MSD which is more reasonably priced.

Useable power band will be around 6200-8000 but what a punch!!! Gas, 110 octane leaded......

Michael, excellent choice! I am sure you will have great fun.

Since you have a 69 mag 2.0l case you need to have the bearing machined in (the 1969 2.0L cases do not have this)

Good point Chad!

Any other bits I should add.

Michael

I know we've spoken before about your build Michael and possibly changing out cylinders, but maybe Nickies? Weight reduction is nice, but you'll have more dense intake charges than you otherwise would with cast iron cylinders or birals. We've seen 15% more HP when switching to Nickies from cast iron and biral slugs. Not sure of the rule limitations though, but I would guess by the amount of other changes, that it should be good.

I would also recommend putting in the piston squirters, as it will help keep the temperature down and hopefully keep the pin and pin boss in and attached to the piston longer at those RPMs. When ordering your pistons, reinforced skirts, forced dual pin oilers, and split oil return would be nice options to add to the JEs. Some thinwall .120" tool steel pins, although a little more expensive, will offset the weight of the reinforced skirts (they help keep the pin bosses in the pistons @ high RPMS and also support the skirts better). Running the JEs in a set of Nickies would also help by keeping the clearances significantly tighter than in a set of cast iron cylinders.

I think the nickies would be allowed and you also get the better cooling with them !

I must get me a set for next go over.

Thanks for all your input.

I look forward to posting pictures through out the rebuild.

Michael

I don't know why anyone would recommend ANY rod over Carillos, ecxept for cost reasons and then it may be a false echonomy. If your going racing go with Carillos. Ask the people who have been vintage racing for a couple of years what rods they are using, the ones who havn't had any engine problems that is. Out of all the dollars you are spending its only a few hundred more for the very best. Thats unless you can come up with some original factory Ti rods, but the price.. well if you have to ask forget it.

Some of my vintage racing friends have had some bad experiences with the Carillos. Not sure the specifics though

The subject of rods for 66 mm stroke engines has been covered before in this thread

A couple of questions back to Walko which might help focus his list of "to do's" a little better:

1) What are you planning on for a rev range? Pick a 2500 RPM range where you plan to have the motor spend most of it's time when on the track.
2) Related to the first question: How long do you want the motor to last between rebuilds?
3) How much do you want to pay for fuel?

To answer the questions.

I don't care where the motor is in the RPM range as long as I am making the most torque and Hp I can.

The gear ratios will be set up so there is 1000rpm drop between 1&2 and then 800rpm between the rest of the gears.

My aim is to have a top speed of 240KMS approx 140MPH.

I figure that as long as I keep the service up to the motor it should last at least a season if not two.

the track events are three 8 lap races approx 6 to 8 times per year.

Fuel will be avgas ie 100plus octane

Michael

Michael,

I've run a lot of gearing combiantion simulations and your description is very optimistic unless you are planning to run really tall 1st and 2nd gears.

Let me know the powerband you are looking at and I can give you some ideas on gearing!

They never are because it probably was something dumb that they did to cause the failure.

1st and second gears will probably be a bit taller than most people would recommend.

I am planning on working out the 5th gear ration and then work backwards. to ensure the rpm drop works.

I know that this will probably give me a disadvantage off the start line but I wol drather come off the line slow and not run the risk of breaking the gbox.

The class that the car will run in has 302 mustangs etc so I do not expect to be at the front unless we get longer races. In the short races the big V8's brakes and tyres wont fade. I think that any race over ten laps the V8s will have a problem and I hope the little porsche might show them up.

Michael

Walko,

THe most important thing for gearing is which track is it going to run on. Ideally you should have a set of grears for each track, but most of us have to settle for what works best on the largest number of tracks possible. There are 3 basic tracks to consider, short tight tracks with low top speeds, medium tracks with some 100 plus MPH speeds, and long high speed tracks with whatever speed your engine can support, ie 150 MPH for slow cars and 200 MPH for faster ones. Most of us have to live with the medium and short courses so we can usually leave out the tall gears for over 145 to 150 MPH. Next specific track info is really required for any honest gestimate of gears.

Jack,

I am planning on building two boxes to start with one for what I call the technical tracks ie short straights and low speed corners and the other box for what I call the HP tracks where the straights are long and fast sweeper type corners.

Michael

How would the GE60 run in a 2.0S street motor (idle, etc.)? CR would be ~10.5:1 w/ twin plugs. How do they compare to the stock 'S' cams?

The GE 60 cam (my DC60) is a little much for a street driven 2.0. The 10.5-1 compression ratio will help the mid range power. In the 5000 to 7800 rpm range the 60 cams have a big advantage over the factory S cams. I prefer my DC40 (Mod-S, GE40) profile for a street driven 2.0 litre. The powerband will be 4000 to 7500 and the idle and low speed driveablity is much better.

Michael,

Go with one or the other box. See what happens and you will know what to do next.

I have seen many rod failures with Carillo rods that were not the fault of the builder. Small ends breaking off.
Talk about catastrophic failure. The whole case gets sawed in half. The only other Porsches rods that I've seen break at the small end were Titanium and those were in 700 hp 935. We all know Ty rods work harden causing failure but what could cause the Carillo rod failure? I don't have an answer but it was troublesome enough for Carillo to redesign their rods.

Carillo rods are still the best there are. Porsche rods are a close second best and In my opinion all others are something less. Nothings perfact or indestructable. One thing Carillo does do is to look into what actually caused the failure. Much of the time its not the rod, but something else that led to the rod failure, eg lack of oil. I have talked to people who have built Porsche engines with Carillo rods that have supposidly failed. Every time, so far, they have admitted to not doing something exactly the way Carillo recommends. EG I have a better way to tighten the rod bolts. So is it Really the fault of the rod??? Carillo certainly isn't in the mode of saving pennys to make a less expensive rod.

Small ends breaking. What did Carillo have to say? Nobodys perfact, but exactly what broke and why? There is no mystery to properly analyzing a broken engine, just time and money to do it right. Redesigning a rod is tacit admission of a problem, but it may also may just be compensation for some other problem. What does one do from an engineering point of view? Fuzzy, non exhistant details on what and why an engine failed, exactly how do you fix a problem like this??

If someone wants you to build the ultimate engine, cost be dammened, what rods will you put in it? I made the choice for my personal engine, Carillo.

http://www.carrilloind.com/pdfs/10777_eprint.pdf

The small end. Is this possibly realted to the small end "problem" http://www.carrilloind.com/tech_archives2.html

Arrow makes a damn good rod too, on par quality (and price)-wise as Carillo. They use a proprietary alloy that is above chromoly, but i'm not 100% sure if it's like the 300M material being used in extremely high dollar builds. Unfortuneately no one makes a billet 300M rod for Porsches- now that would be awesome.

Seems like LN would be in a good position to start. :D

Well here's your chance- my good friend Mike Riechers of R&R Racing Products is considering expanding into doing rods for Porsches. He currently only does custom billet aluminum rods, but being that he's set up for doing lots of one off custom rods, moving to steel is a logical progression. His site is http://www.rrconnectingrods.com. Maybe some well placed phone calls or emails might give him incentive to do so. He has access to 300M, but the material has a wonderful 46 week lead time (I checked last week just for this reason). He's been doing rods for a long, long time....

My vote is for Pauters, damn good product!

So why not just buy Carillo??? Proven porduct, available, sort of, and usually dosen't break. From an engine builders point of view, its a no brainer. Whatever breaks probably won't be the rods. And this is not to say that there may not be other rods just as good, its just a fact that Carillo is the gold standard at this point. That makes it a rod builders problem, NOT an engine builders one. The second best must somehow overtake and replace the current gold standard, a very very tough task indeed. Especially in a world where cheeper and better is not a factor, just better.

KIND OF A LAST WORD FREAK, AREN'T YOU? :)

My last word:
Build your 2.0-2.5 race engine with 2.2 factory rods.
Take the $1200 difference and go to driving school and you'll be faster by seconds and that after all is the point.

The rods will never fail and you'll be less likely to over rev the engine which is the cause of most rod failures in 2.0-2.5 race cars anyway.

Yeh, Carillo, Carillo and Carillo.

You are almost certainly correct, for most people a good set of factory rods is as good as gold. But are you really saying that the factory rods are every bit as good as Carillo rods??? I doubt that and for those willing to pay for the best I would not sell them a set of factory rods. or any other rod than Carillo. Most people cannot drive a Porsche or BMW even close to its capability, but they pay for them and they expect the performance they offer. Giving someone less than they are paying for, even if they can't utilize it, is not our choice, its their money afterall. Some even have the capability to use it to the limit.

Thats my last word, unless you respond, in which case I will have to have another word or two. or three, or four.