What to do with a 3.2 Carrera engine....

[jsoderbe]

Hi guys,

I just bought a 1988 3.2 Carrera engine on UK Ebay. It wasnt planned at all, not by a longshot, but it usually works out great in the end....

So, the engine is from a wrecked car, so the left chain housing is broken, the intake is missing and sheet metal is damaged. It might have more problems but at least it turns. I basically paid for a crankshaft, so I cant really expect much.

Anyway, now I need to make some plans for the engine. It has no injection system, so it will be a carbed engine. I will probably go the PMO route. Exhaust will be SSI since I need the heat.

So the question is really how far I can take the stock parts? I want to stay with the stock heads, but I would love to change the cams for more high rev cams. What would you guys recommend me to do? Which cams can I go to and still stay with the original heads?

So my budget allows for cams and carbs (and maybe a mild porting), plus the entire rebuild of the engine.

Recommendations would be very appreciated!


Regards,

Johan

[jsveb]

There are others with far more knowledge about this than me.

But, if I had an engine like that to toy around with, I'd go MS EFI on ITBs like what Al Kosmal did. You could either build it yourself, or buy it from the DZUG guys - They are all Pelicans.

DZ X-Factory ITB Setup

[jsoderbe]

Nice....

Is there any dyno numbers floating around with that configuration? I would love to see a comparison to carbs or motronic.

I think I am most concerned about the pistons. They are 10.3:1 Euro spec ones, which make the compression reasonable for bigger cams. But, are the shape on them ok to use with a bigger cams and carbs? Or do I need to get JE pistons?


Regards,

Johan

[Raceboy]

You can use the stock pistons with hotter cams, no problem. I would also suggest to build an EFI ITB system, I have done this on 2.7 and 993 engines (plus many non-911 motors), I use GSXR1000 throttles.
Contact me if you're interested.

[AlfonsoR]

Raceboy, that's a nice set-up. Do you sell those as assemblies?

[Raceboy]

I have done those 911 and 993 conversions for friends and I am going with the same throttles on my 2.5 SS turbo engine (but of course with dual-plenum system for forced induction).

But I think I could put together a set for sale also. Good thing is that these throttles have TPS installed and also have injector bosses.

[AlfonsoR]

Well, right now I do have an engine build to do on my 3.2, but I was going to stay fairly stock. At some pont in the future I would like to do something like what you're talking about, but not anytime soon. I just wanted to get a contact for whenever it comes up. I seems like there would be some fair savings going you're route compared to doing injected PMOs.

[Raceboy]

Originally Posted by AlfonsoR

I seems like there would be some fair savings going you're route compared to doing injected PMOs.

Yes, and that was the main reason I went this route (many times). There are two bonuses also: they do not perform worse than expensive off the shelf stuff and also the quality and precision of the OEM throttles is top notch.

The length of the intake is variable with the trumpets mounted with silicone couplings (one can get estimate using the calculator and fine-tune the length on the dyno). A bit time-consuming it can be, but the possibility is certainly there.

One of my friends is a the head of our local Formula Student team and they developed continiously variable length ITB system (actuated by servo motor and controlled via standalone ECU) for their motorcycle engine equipped formula. Something that would be a neat idea on normally-aspirated 911 motor also.

[jsoderbe]

Hi again,

how do you feel about

RSR cams
10,5 JE pistons
Heads ported to RSR spec 43/43 mm
PMO 50 or Weber 46 (if I can mill out my crappy 40:ies)
SSI and 2,8 RSR style muffler

Do I need to go twin plug? I know I should, but it will mean lots and lots of additional costs....

What else so I need? Maybe the RSR cams are too wild, I am not that much into high revs. Is there a better cam choise?

Thoughts? Would I break 300 hp?


Regards,

Johan

[Raceboy]

Without proper oiling mods, better rods+bolts I think you are not going to be able to effectively use the powerband of RSR cams/headwork.

And as I mentioned already earlier, going twin-plug is actually not too expensive (if going wasted spark coilpacks), but it will get expensive if you prefer to stay period correct, meaning 12plug distributor.

[jsoderbe]

Ok, you are right. You mean cross drill crank?

If I put it like this; I would like 260-300 hp, good drivability but I want an early 2.4 S-type power distribution. Meaning, the engine should really wake up over 3k and scream over 5k. I dont need to rev 8k, I am fine with revving 7200-7500 maximum. Is that too much for the stock rods?

Any suggestions on cam choice? I was kind of hoping the increase in displacement would smooth out the RSR cams a little.....


Regards,

Johan

[Raceboy]

Over 7000 is too much for the stock rod bolts, you would have to use ARP for sure (this is recommended even with stock redline).
Oiling mods would include at least cross-drilling the crank, using 930 or GT3 oil pump and grooving the main bearings. Not sure if it is needed for occasional 7200-7500 rpm though?

I would go with S cam profile but perhaps someone could chime in with recommendations?

With better cams, higher CR and twin-plug 260 hp would not be a big deal (Euro engines had 231 hp in stock form).

[jsoderbe]

Hi again,

Now I have started to take the engine down to the crank. Unfortunately the engine was a US 9.5 comp engine, whatever that were doing in the UK.

The condition of the engine seems to be very good; cams look new, no noticable carb buildup anywhere and it doesnt even have any bad oil leaks.

And, it has Alusil cylinders, at least I think there is a KS logo on the cylinder base.

So I think this is not the right engine to build a monster motor out of. Right now I am thinking to just repair the cracked chain housing, and maybe change cams and put carbs on it. That would give me a nice reliable period-correct looking engine while building something nicer.

So now my question is which cam profile to use? That mean a standard engine with alusils, Motronic pistons and preferably Weber 40's. Should I use stock or 964? Would the pistons work with any hotter cams?

Would weber 40's work with the 3.2 displacement?

It is really hard to figure out which way to go....


Regards,

Johan