nine-44

Log manifolds get the job done, some pretty successfully too. There is merit in taking things further. A poorly designed 4-1 or 4-2-1 can be worse than a simple log as well. Simplicity and packaging point to a log style. I would suggest stepping the size up as each runner is added and flow it the best you can. Try to bring in the runners to the log at an angle but keep room for accessing the bolts, I wouldn't do 90 degree intersections. I've heard of a saltflat car that ran box steele with NO runners, just holes in the side and flush against the heads. It was a 383 chev putting 800 HP out! Do the best you can as far as directing flow towards the turbo. There was a BWM race 4cyl that they gained like 80-90hp by going to a tuned header from a log style. Do the best you can from the start, you may need that extra effort in there to make up for something that you just can't avoid later. Trust me man, it'll be worth it. Remember to run oversized hole for slip due to expansion. Note, as exhaust is collectedfrom added runners, the heat load will rise across the log. The first runner will be the coolest and more heat as the other come into the main flow. Don't connect the flanges either, you want it to absorb some expansion between ports and have some flex. Run thick flanges, probably3/8-1/2" and get them machined flat after welding. I'll keep thinking of what else would help...

fwb42

Those of you that know anything about turbos,might want to check out this new Co.<www.turbodyne.com>.They are a restart of the original Turbodyne Co.that ran out of $$.If you would like info, e'mai the ceo.he has always answered my e'mail. Disclamer:I am a stock holder,but small potatoes.This might make some of these conversions easier.Let me know what you think....FRED

Geo

Andy has good advice.

Don't listen to the negativity. You are getting good advice. Some people just never have anything good to say.

Rock

The day peckster says anything supportive is the day i die

Zero10

So, what about using a thick-walled log style manifold? You could angle the runners down a little bit to aid in access to the bolts, just go straight out, 45* bend, then 45* entrance into the log, maybe 2-3" from the head itself. Then straight down into the turbo. If the walls of the pipe are a bit thicker, the header wouldn't move as much, and you could probably use smaller bolt holes on the flanges at the head, as well as stock exhaust gaskets. It would be about 100x easier to make a log manifold, and without being able to really flow-test an individual runner manifold, it might be a better solution?...

Still curious on the water cooling as well.

Campeck

ill take the water cooling from the pipe that runs right above the headers. does anyone know if that pipe flows water only when the heat is on or all the time?

Dmitry S.

Water flow is controlled by the heater control valve. Take out the valve and it will flow constant.

inactiveuser92616

as I recall, that is some seriously hot water in that pipe. As I remember hearing it explained, the reason the 944 heat is so strong is because the water going through the heater core has already been heated through the engine. If that is the case, you may want to pull water from a cooler source... post radiator.

Zero10

Yeah, not the best location for a water source. IMO you should turn the elbow on the turbo water pump around. Draw water from the same place, then feed it back into the tube that runs over the headers.
It would be a really simple modification to do.
Although, I am always very leery when running rubber hoses near exhaust parts, so perhaps some hard piping should be run to keep the rubber parts away from the headers/turbo.

nine-44

Hey Campeck, her's a quick idea for manifolding, 928S4. I have the left one flipped on the right side but...

The runners are a little long and the flanges are wrong, a little work and you may be ahead of the game with one tho. As is, the log is against the strut tower, about and inch to an inch and a half and it would slide in with new flanges.

Zero10

I've been staring at LS2 manifolds all day. They are just a very simple block-hugging 4-1 design. Except for the slant at the bottom, they would be perfect for this application.
Then again, after staring at those manifolds, I decided that engine would be perfect for this application

scular

Just to add a little more to this long discussion. I already turbocharged my NA. To everyone that says not to do it or it cannot be done... :P It was a blast until the line going to the wastegate came off and the engine saw way too much boost and split a cylinder. LOL it is going to make an awesome coffee table. Oh, and the car still ran with a split cylinder, it just poped the coolant resevoir which needed to be replaced anyway. Well one year later (under $1000), I have another 944 NA block that I freshened up, I am about to put the turbo onto the engine, and drop it into the car. This time I am using better hoses and double clamping that stupid hose.