Andial 3.7L CIS Information

[Packy]

Does anyone have information on this engine? I am reading about it in Wayne's book and I seen it mentioned before but I can't seem to do a good search on the engine.

The information I have on it is as follows:

3.0L SC case
3.2/3.3 crank
Andial 104mm P/Cs
964 cams
CIS
3.0L heads
10:1 compression ratio

It says this engine was sold to a Pelican and puts out 280-300 HP.

Anyone have more on this thing?

Thanks,
Patrick

[JP911]

CIS on an engine like that would be a crime. It just wouldn't breathe enough to maximize the motor's potential. I tried CIS on my 3.5 with 964 cams and it was night and day when I switched to carbs.

[911st]

Something dose not sound right. I believe they used a 964/993 crank and 100's for there 3.6. Maybe 102's for a 3.7. Not a 3.2 crank.

Years back I think a company called BDR did a 3.5 CIS that put out something like 260hp. I could be wrong as this was like 25 years ago.

There was a Silver Targa that Scargo built than had a CIS motor that I think took a Silver State 100 mile Record. I think it was a something like 265 hp.

CIS can make HP. It can even have decent throttle response with compression and if you use a WUR with an enrichment function on it.

What would be fun is to take a 3.0 turbo out to 3.6, keep it CIS, bump the compression a bit and run low boost. Could keep the stock tail and appearance and approach 400hp.

Run what you brung.

[JP911]

Enrichment = more fuel. The issue with CIS on a big NA engine is air.

[911st]

I suspect of 36mm port can support 250hp (my old 2.8 mfi), a 39mm should be able to support more than that.

If we set our idle and cruse AFR near 14/1 and wish 13/1 for max TQ, we need more fuel. USA Porsche CIS cars do not have an enrichment function and can go to 17/1 AFR on first accel. This is part of the reason along with the low compression why CIS is not know for its throttle response.

Set CR to 10.5, lower control pressure with accel so the metering plate starts moving so we get in instant 13/1 AFR on top of twin plug ignition and it will wake CIS up.

It may not match a well set up carb but there is potential there.

At least that is my believe.

[emcon5]

If you look beyond Porches, lots of people have found that Bosch built a lot of headroom into CIS. The commonly accepted figure for the Rabbit GTI is ~140 HP before you have fueling problems. The stock HP for that engine is 90.

Only person I know of who tried it with a 911 was "rdane" who got ~223hp to the wheels with a 3.4 with early CIS. Details here Assuming ~15% driveline loss, that is around 250HP for an engine that came stock with ~180.

Originally Posted by 911st

I suspect of 36mm port can support 250hp (my old 2.8 mfi), a 39mm should be able to support more than that.

My 3.2 CIS kind of falls on it's face up top, I expect the small ports are largely to blame. But they are 34mm, not 36.

If we set our idle and cruse AFR near 14/1 and wish 13/1 for max TQ, we need more fuel. USA Porsche CIS cars do not have an enrichment function and can go to 17/1 AFR on first accel. This is part of the reason along with the low compression why CIS is not know for its throttle response.

I don't think this is correct. I know the CIS-Lamda does, from the Lamda box, triggered by the full throttle switch. The CIS basic had enrichment through the WUR. The factory manual show 2 different control pressures, with and without vacuum. They system gets richer when manifold vacuum drops.

Set CR to 10.5, lower control pressure with accel so the metering plate starts moving so we get in instant 13/1 AFR on top of twin plug ignition and it will wake CIS up.

Twin plug is pretty much mandatory on that bore size.

Honestly, For the time and effort involved with building the Andial engine, unless you are doing it for a engineering exercise, save your time and money. Sell your engine and put the proceeds toward a 3.6.

Tom

[911st]

Well said.

Thanks for the correction on the two CP's. The 930's after 78 did not work that way which is more my reference. Playing w the CP's to make the AFR's more ideal along with blue printing the ignition side could be an area that yields solid advances. Kind of like getting the jetting right on carbs.

A 3.6 w just carbs and exhaust can get to 300hp w/o a lot of fuss.

A nice build it a 3.2 short stroke (bored 3.2 cylinders w J&E's). Add some compression & the right intake port set up and one can have a sweet motor. I do not know if the C2 cams make that big of a difference if the exhaust is good. If I did this I would look into cam options other than the C2 to extend the rpm range to take advantage of the rev potential of a short stroke build.

Reasions to keep CIS:

live in a smog state
maintain the value of your car
dose not fuel starve in high G turns.
low maintenance or worry system
you already own it v $3900 for a new carb set up.

I suspect a near 300hp CIS is possable and could be fun.

Not an expert, just what I believe so far.

[JP911]

I didn't say that it couldn't be done or that it wouldn't run, but the motor will not reach it's potential. It's kind of like running snow tires on your newly built race car.