3.2 US Franken-CIS to 3.2 Euro EFI build
 

Gents

I've thrown myself into a new and hopefully fun engine build. Not my engine, but I'm doing the planning and the wrenching. Dropped the engine this weekend, and I started to dig in right away.

It's a US spec 3.2 long block, fed by a '78 CIS. Stock exhaust manifold and a nice Dansk sport exhaust. We need to fix some oil leaks on the way, but the owner is really looking for more power :D and would like to have a shiny new engine, so cleaning and painting is warranted.

Naturally, we needed to get rid of the CIS asap. This is a budget(isch) build and I have some very nice Carrera intake manifolds (mockup):

http://forums.pelicanparts.com/uploa...1542641712.jpg

I also have these babies:

http://forums.pelicanparts.com/uploa...1542641712.jpg

So that's our starting point: New 3.2 Euro pistons and Mahle cylinders. Original 3.2 manifolds. And a MS ECU on the shelf, so we're going EFI.

I would like to use 20/21 cams if I can get the stock ones re-ground. Trying to convince the owner to change the exhaust - we will see.

I could use some advice on the EFI. I believe 30lb injectors should be able to do the job. But looking at the manifold, I think the injector sleeve is very small and not very deep. Any suggestions for a suitable injector?

Also: The engine has none of the original 3.2 sensors and no idle valve. I will add the usual sensors for oil temperature, manifold air temp etc. and we are debating wether to use the Bosch CDI and SC dizzy or go full ignition via MS. Budget is an issue here.

I've done several EFI conversions on 3.0's both with original manifold and ITB's. I haven't used the AAR so far, which hasn't been a problem. Do we need the idle control valve (or AAR) on the 3.2 manifold?

Cheers!

Nux,

I ended up selecting a set of Bosch 0280 155 931's, which are 28.55lbs/hr at 3 Bar. They are a modern 4 hole "bolt in" upgrade for the original 0280 150 158's (22.8lbs at 3 Bar) and work with the original harness connectors and found them to work well with the standard Motronic setup. (AFR verified on a dyno.)

I also expect the 931's will also have enough headroom for my 3.4 litre conversion with full sequential injection.

Perfect - thanks.

They could be close to 100% duty cycle for your 3.4 build, don't you think?

Nux,

You do not absolutely need an electronic IAC valve, you can set the warm idle with the throttle stop. But, if the car does not have a hand throttle, it make cold starts hard. You could use the CIS AAR for cold starts.

What version of Megasquirt and firmware are you planning to use. A lot of people use Ford EDIS wasted spark for ignition which is fairly cheap to install, but the stock ignition can be retained if desired.

i dont know why you would not want the idle control valve. why go to the trouble to put modern injection on it to not have modern features.
Also do the full electronic ignition. its well worth it.

Well I guess you're right. I'm just considering my options, since the induction on this build will be completely from scratch. There is nothing right now - besides a good looking raw manifold.

I have both MS1 extra and MS2. Never really tried MS3. MS1 extra is perhaps a little rudimentary, but does the job.

The MS2 firmware is 3.1.0 and has the EDIS option. A completely new MS2 ECU is about 700$ over here, so not too bad in case the one I have doesn't work correct.

Update.....

well things have changed. I noticed after pulling the CIS, that the heads were not from a 3.2 as the owner had been told....And I should have seen this when we pulled the exhaust.

http://forums.pelicanparts.com/uploa...1543399486.jpg

So standard early SC heads then. No porting.

It's a 3.2 case, so maybe they put together a 3.2 with a big-port CIS top then?

But no......

http://forums.pelicanparts.com/uploa...1543399486.jpg

http://forums.pelicanparts.com/uploa...1543399486.jpg

Erheemmm allright, change of plans then!

Current plan: Wössner 10.5:1 CR pistons, 993SS cam, Twin plug, EFI on the 3.2 manifold and finished off with SSI's or maybe the new M&K active exhaust.

The engine was rebuilt less than 30tm ago, so we're not going to split the case. I suppose it is possible to check the #3 rod bearing without splitting the case to make sure?

For the idle control valve, Volvo uses the same one that is far cheaper than the Porsche one.

Gotta love the Porsche tax!

Found the oil leak: Broken top seal. http://forums.pelicanparts.com/uploa...1543864320.jpg
http://forums.pelicanparts.com/uploa...1543864320.jpg

I've been thinking about cams.....again. I know the 993SS/10.5cr/plenum/EFI combo works. 964 and 20/21 are too mild for my taste.

Maybe you guys have an alternative?

Re your injector injector question, I'm running Ford Motorsport purple 24 lb on my 3.4 10:1 compression with MS2 management and duty cycle is no more than 50% . As they are a EV6 connector, a new harness had to be made up, no biggie. This is on a 3.2 engine with 964 cams, no barn door air floor meter, stock heat exchangers with no cat and free flow muffler.

New year update.

Dougherty special grind DC24/21 cams are on the way from the US. Wössner 10.5:1 pistons are inbound from UK, heads are being twin plugged in DK.

Head studs changed, wiring is ready for EFI and engine is ready for a shiny new finish. Should be good!


http://forums.pelicanparts.com/uploa...1546591709.jpg
http://forums.pelicanparts.com/uploa...1546591709.jpg
http://forums.pelicanparts.com/uploa...1546591709.jpg

Looking good Nux. Careful, you might give up your other line of work and open a Porsche resto shop. :-)

That's interesting. I just adjusted (raised) fuel pressure to some 60psi on a 3L semi-race engine running twin plug ITB EFI using those same injectors because it was getting too close to the duty cycle max at high rpm (7k+). Engine makes about 300bhp.

Sorry to derail!

what octane are you planning on running with this set up

are you dumping the old SC cylinders too?

Haha don't think I haven't thunk about it! :D

I really injoy working in these cars. And the engine is my absolute favorite!

We all use 100 or even 102 RON here.

Sadly no. Budget is tight.

Assembly time
 

Finally I've got all the parts home again. Powdercoated everything.

Heads opened up to 41.5mm and matched to the 3.2 Carrera intake. Ported nicely - and twin plugged of course.

http://forums.pelicanparts.com/uploa...1548358374.jpg

However, I noticed that the new plug hole sits a little deep. This means that the plug will protrude somewhat in to the combustion chamber. I'm worried that it actually might interfere with the piston.

http://forums.pelicanparts.com/uploa...1548358500.jpg


A little difficult to see, but the right plug is not level with surface of the combustion chamber. Should I shim it up a bit??

German Wössner pistons 10.5CR - nice:

http://forums.pelicanparts.com/uploa...1548358500.jpg

And US based John Dougherty special grind 24/21 cams:

http://forums.pelicanparts.com/uploa...1548358500.jpg

Twin plug dizzy on it's way from Tuthill, England.

To be assembled in Denmark.

This is truly a trans global build :D

Looks fine!

Got some work done this weekend. I really need to buy Stomski's circlip tool. My thumps are killing me.

http://forums.pelicanparts.com/uploa...1548619620.jpg
http://forums.pelicanparts.com/uploa...1548619620.jpg
http://forums.pelicanparts.com/uploa...1548619620.jpg
http://forums.pelicanparts.com/uploa...1548619620.jpg

I'm always surprised just how much work it takes to make one of these. Especially if you need to customise some parts - and I hate working on old rusty oil lines. Twin plug is a lot of extra work - and money!!! I really like the twin dizzy look, but the price is pretty steep compared to coilpacks.

Also, I needed to order stuff from no less then 6 different shops, as no one has everything. Quite annoying.

I ended up with:

MS EFI, Holley injectors.
New Wössner 10.5:1 pistons in freshly honed cylinders.
SC Heads twin plugged and ported to 41mm, matched to 3.2 manifold. They were lightly flycut as well, to clean up some minor damage.
Tuthill converted twinplug dizzy (amazing guys, good price as well).
DC 24/21 custom grind cams 114LC.
SSI and two out Dansk exhaust.

I'll be using two standard Bosch CDI's and coils. Also, I'm using the standard 3.0 throttle body, which fits the 3.2 manifold perfectly.

Could this be restricting air flow at high rpm (the fitted airfilter is just for show)?

http://forums.pelicanparts.com/uploa...1549953118.jpg
http://forums.pelicanparts.com/uploa...1549953118.jpghttp://forums.pelicanparts.com/uploa...1549953118.jpg

So the engine is starting and running. No oil leaks. So far so good.

But at idle it has a high pitched whistling sound from the left bank and it's running rough. AFR's all over place (Lambda on the left bank), but mainly way too high. So I have a vacuum leak somewhere. Took me some time to diagnose where. Had the manifold off two times to check gaskets, rechecked manifold bolts etc. No obvious leaks found. Since this is EFI, there are really no other sites for vacuum leak.

Carb spray around cyl three: Sound disappears and idle goes up.

Well after some head scratching I've found the problem: Vacuum leak on cyl three injector! These are brand new Holley 42lb Injectors. Tried to take them off, place them a little better, even tried Curil T on the O-ring, but no help. Injector seat is fine. It's driving me mad I tell you. It's the very last bit before the car hits the road.

So, I guess it should be pretty straight forward; replace the injector and if that doesn't help, bigger O-ring I suppose?

So close!

Is the o-ring damaged? The seating hole in the manifold clean and smooth?

Using a little oil or grease to allow the o-ring to seat easily?


Keep at it! Keen to hear how it goes on the dyno!

Everything looks fine, which is even more annoying. Going to change the injectors and see whats happens.

I hope 250hp is within reach with this build. We will see!

The injector pocket on the 3.2 manifold may be overlapping the edge of the 3.0 port causing a vacuum leak.

Compare a 3.0 and 3.2 intake gasket.

You are correct sir. Thats why I've cut the gaskets my self to at perfect fit. And I've triple checked those. Did also try with 3.0 gaskets and even with Locktite 574. No change. I'm faily sure it's the injectors.

If I cover the intake gaskets and spray directly at the injector, idle rises and the Sound disappears. You can even see the fluid getting sucked in.

Good then, carry on!

Curious why you went with the expensive and not particularly flexible twin plug distributor when the mcrosquirt could run dual COPs in a wasted spark configuration at the cost of a flywheel mod, crank position sensor, and plug for the distributor hole.

Seems like that would have been ticked all three boxes: Better, Faster, Cheaper. How often do you get to do that?

:)

I absolutely agree. But I'm building this for a friend and he specifically wanted the twin plug dizzy look. I tried......but no :)

3d print one :D

I went custom twin-plug distributor exactly for this reason, to have retro look. It is locked and has Hall sensor for cam sync, coils are fired directly from VEMS :)

http://forums.pelicanparts.com/uploa...1552933152.jpg

Nice!!!

Resolution!
 

After many many attempts with the 3.2 manifold, new gaskets, new injectors, different o-rings etc - well I gave up. After I'd pulled the manifold for the fith time I tossed it in the trash and fitted these:

http://forums.pelicanparts.com/uploa...1553512255.jpg

ohh bliss!!! No odd vacuum leaks, no bouncing AFR, no strange noises other than the lovely symphony from 6 airhorns

Now - tuning! I'm hoping this thing will put out about 250hp at 7000rpm. We'll see.

After a few setbacks (again) with a bad coil and a defect voltage regulator - it's back to business with tuning. This thing pulls like a train now!

I'm using 30LB injectors and I'm seeing close to 100% duty cycle at 7000rpm. Need to get on a dyno next!

First dyno session
 

First dyno session today. We didn't have long and were just beginning to dialing the fuel and ignition in.

Had maybe 10 runs in total. I'm was still correcting fuel efter a changed the ignition from 5BTDC to 0 to see what happened. What do you guys set a twin plug to?

Anyway, good thing and bad things. Nice flat torque curve with max at 295. HP was 242 at the engine, but I'm pretty sure I can get that up to 250+. I didn't even have time to run a log. That has to be next time.

http://forums.pelicanparts.com/uploa...1557849550.jpg

Now, the bad thing. I'm could see quite fast, that the AFR couldn't really stay at 12.5 isch, but was creeping up to around 13-13.5 just before 6000rpm. I know the old injectors were running 100% duty cycle at WOT at 3 bar pressure. And I didn't watch the new ones (42LB) this time, but I'm wondering if the old fuel pump is up for the job? The injectors should be more than fine.

http://forums.pelicanparts.com/uploa...1557849849.png