Joe Ricard

So Now all we need is a written procedure to do the swap. I got my eye on two 944 's with the engines still in them. Got the euro intake runners just need a throttle body. Hook us up man.

Jim Nowak

Mark,

To support that kind of power, what size injectors do you think would be recommended?

Jon F

Jim, what did you do with the cooling ports? Do you have pictures? Thanks!

Jim bailey - 928 International

As I recall Lucky Eckman (who with Bob Devore started DEVEK ) was the person responsible for the design and building of this engine and as has been mentioned before the project has taken a couple years to get to the current nearly finished state . This may be one of the first engines built in many years using J E aftermarket pistons with a "special coating" to run in the Alusil block . The reliability of the 104 mm pistons is a much bigger question than how difficult it was to fit 944 heads . Jim has been the very patient owner and sponsor of this project but I do not believe he was involved in the details .........

mark kibort

I think it would just be a matter of upping the fuel pressuer . recent investigation shows that with the two valve engines, and their two fuel regs, one can be plugged or the return line clamped off or plugged to increase fuel pressure. keep in mind stock pressure is around 33psi, while s4 pressures out of one simular fuel regulator, is 47psi.
could be a cheap fix for raising fuel pressure, and use an adjustable regulator with the clamp off for full adjustability.
I had stock injectors that were flowing enough to support 293hp at the wheels and fuel ratios in the 12:5 :1 range to redline

MK

Carl Fausett

Mark K,

I believe the non-turbo (up thru 84) valves are samller than the turbo (85-on) heads for the 944/2 (951) Pretty sure about this, but not positive. I have heard elsewhere from others that the 951 heads were the hot items on the 928... and when my son and I were rebuilding his 87 951 and my 928 we were swapping parts all over the place for fun - yes, his heads fit (with modification for water passage in the front) my 4.5Liter 928 block. We were amazed as we rebuilt his motor how many part numbers in his engine started with 928... I really loved rubbing it in! But that is no surprise gievn the history of the two cars and their design dates.

Anyway, I ended up buying a set of the "big valve" Euro heads and cams from Mark A at 928 Intl instead, so I never pursued the 951 heads on my block any further. But it was certainly do-able without too much trouble.

Formula94lt1

Seems like you would have to do a 180 on one of the 944 heads so it would face the correct direction on the opposite bank. I am curious , since the back of one cylinder head is now the front, how you attach a cam sprocket and such...

Vilhuer

There are mounting points ready in heads AFAIK. Sprocket is only mounted to cam anyway and other stuff should fall into place relatively easily.

928 use same parts in many places on both heads. 944 engine is passenger side half of the 928 engine. If parts fit into 928 passenger side they will also fit in drivers side as long as their basic design hasn't been changed. Which should be case in two valve heads and in 2.5L 944 in general. 3L S2 and 968 is little different.

hacker-pschorr

There is another forum right above this one that holds all kinds of answers

Try this:
https://rennlist.com/forums/924-931-944-951-968-forum/329992-valve-size-question.html

The hot ticket would be 89 2.7 liter heads with 47mm intake valve's. If you are using stock 928 cams with a supercharged motor, no need to spend the extra coin on turbo heads.

a4sfed928

Can you elaborate on this...?

Formula94lt1

"There are mounting points ready in heads AFAIK. Sprocket is only mounted to cam anyway and other stuff should fall into place relatively easily.

928 use same parts in many places on both heads. 944 engine is passenger side half of the 928 engine. If parts fit into 928 passenger side they will also fit in drivers side as long as their basic design hasn't been changed. Which should be case in two valve heads and in 2.5L 944 in general. 3L S2 and 968 is little different."

Whats special about the 3.0L 968 stuff that would change anything? Wouldnt these heads be the way to go if it was possible assuming a large enough bore? Variocam!

hacker-pschorr

On what? Not using turbo heads?

Per Special Tool in post #7: turbo heads have stiffer valve springs.
We also know they have sodium filled exahust valve's and coated exhaust ports (to protect against turbo heat). So with stock cams and no turbo, why spend the money on turbo heads when you get the same port & valve size with any other 944 head - except the 89's.

IMO you will spend just as much trying to modify 944 heads to work on a street car as buying EuroS heads. On a track car where you don't plan on using a heater core, the install becomes much easier.

I'm assuming you need an S4 coolant bridge with this setup.

Vilhuer

3L blocks and heads have one water channel in different location.

944 S2 block on left, 944 Turbo on right. Heads are 928 S3 meaning they have same water channels as all two valve heads.



Notice how head doesn't cover water area on block on drivers side front corner.









968 heads are not needed for Variocam. Its not easy but its doable into 928 32V heads too. See what Sterling has done. There is a lot of reading in archives.

Formula94lt1

I take it S3 heads are the 85-86 32v heads, so I guess s4 and up blocks and heads are specific to their own? Are those more similar to the 968 heads?

Fastest928

944 heads fit 928, but you need the cam tower also and have to weld the head. We have a few sets in stock with cam towers, rebuilt and ready to ship. I also have one set of turbo 944 heads ready to go.

We have shipped many of our custom coated pistons with only one piston/bore failure due to over fueling.. a single bore. We will now only use this coating for our own builds.

We discontinued the selling the coating due to liability and other issues associated with selling custom coated pistons. Lucky will build no more, neither will I except as noted above. Lucky built the engine, and did not and will not do the tuning.

Cheers,
Marc