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Cooling system changes for high rpm use.

There is a 1/4 inch pipe hole in the block between cylinders 1-2. Almost a short circuit on the pump when the system is open. I aslo pull water from the back of the head on the intake side.
 
people turn 8v's this high of rpm and don't have problems, kinda surprising it causes these problems on 16v and they basically use the same parts minus the head
 
No problem because of too high pressure

Hello, I'm Kay from North of Germany. Sorry for my bad English. I know this kind of problem. It is not because of to high pressure in coolant system. A very common problem on turbo charged engines are vibrations at high revolutions.
We had this problems at Porsche with 924 GTA too.
This engines did run without head gasket! Seal block and head. two water pumps. even at this engine the core hole close caps went out.
sometimes even the hole block cracked.
At VW we did test on the dyno and have a closer look via hologram on the engine while running. The vibrations are amazing!!!!!

I will try to find something in my papers, but this was long long time ago. Cheers, Kay
 
Welcome Kay, your english isn't that bad. :)

If you've got any information on the harmonics issue, that would be very interesting to see! Most of the crew here won't have access to the test equipment you mention, so I'm sure seeing what you may have available would be awesome!
 
Welcome Kay, your english isn't that bad. :)

If you've got any information on the harmonics issue, that would be very interesting to see! Most of the crew here won't have access to the test equipment you mention, so I'm sure seeing what you may have available would be awesome!

plus 100,000 ! That information would be great ! :nod:
 
Nono, not my equipment

Hello, nono, this is not my equipment, for bad luck.
I was a student and did practise at Porsche in the beginning of the 80's as a "work-student"

This problem of vibrations is only on 4cyl high running turbo charged engines.
We(they) destroyed nearby everything on the dyno.
At this time the computers were slow, no digicams etc.
The core plugs were welded for shure. We lost on the racetrack the part of engine case where the year and month of cast is noticed.
On dyno with hologram and strobo you could see this thing moving!!!! and shaking. Grind it away and problem solved, strange thing.
I did have a workshop for historic race cars and restoration, a lot of tools are still with me. Hard to find things too, like ignition distributor test stands (4x) Bosch and 3 Souriau. A huge improvement on race cars you can do by modifying the ignition.
Back to the article:
You have mass-forces in 1. and 2. grade in engines. 1. is all the moving parts without combustion etc. 2. is with combustion and firing up, the running and power producing engine.
The 2. grade forces on turbo powered 4cyl are amazing and really difficult to handle.
I try to find informations in my documents. The way we fixed it is not in my head anymore, too long time ago.
cheers, Kay
 
Hello, nono, this is not my equipment, for bad luck.
I was a student and did practise at Porsche in the beginning of the 80's as a "work-student"

This problem of vibrations is only on 4cyl high running turbo charged engines.
We(they) destroyed nearby everything on the dyno.
At this time the computers were slow, no digicams etc.
The core plugs were welded for shure. We lost on the racetrack the part of engine case where the year and month of cast is noticed.
On dyno with hologram and strobo you could see this thing moving!!!! and shaking. Grind it away and problem solved, strange thing.
I did have a workshop for historic race cars and restoration, a lot of tools are still with me. Hard to find things too, like ignition distributor test stands (4x) Bosch and 3 Souriau. A huge improvement on race cars you can do by modifying the ignition.
Back to the article:
You have mass-forces in 1. and 2. grade in engines. 1. is all the moving parts without combustion etc. 2. is with combustion and firing up, the running and power producing engine.
The 2. grade forces on turbo powered 4cyl are amazing and really difficult to handle.
I try to find informations in my documents. The way we fixed it is not in my head anymore, too long time ago.
cheers, Kay

Sounds like the raised number portion cast into the block was what is referred to as a "stress riser", I take it?

I've read lots of " How To Hot Rod A BBC /SBC Engine" and grinding all the casting flashing/and such, from engine block was always recommended
 
Wow very interesting! I have a radiator out of a 89 toyota supra (aftermarket fluidyne from summit) and twin flexallite electric fans, huge intercooler from mk4 supra and separate trans cooler.
I removed the expansion tank and i have a 16 pound rad cap. Ive eliminated the heater core. My radiator always dumps out 1/5 of the coolant now matter how much i burp it. So i let the coolant run at this level and it lives happy seeing 25 psi at most on lh 2.4 . I have always wondered why it cannot keep the radiator full to the top. My thought was it needs a higher pressure cap, but as far as i know the highest ive found is 16psi . I rev to 7100 rpm some times. Havent had a freeze plug issue yet . And its a original "sat in a junkyard for 5 years" na motor. Never had the head seperated.
I have noticed that it always pushes the coolant out at idle when the car is sitting still (after i fill it completely) and it doesnt seem to be from hi temp, as the water is warm.
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Kris Weldy
 
It would probably cost a good bit but, I wonder if it's possible to port the water channels using a media blaster... Kinda like what they do for stock cast manifolds in restricted race classes. And it's already been covered but.... A Universal Electric Water pump with a special outlet from the block would also work very nicely and never be overspun due to the High RPM.
 
Volvo freeze plugs??

I'm going to chime in a bit here.

1. In any motor we build we only use stock VOLVO freeze plugs. Early on I used dorman and other aftermarket stuff and they would seemingly push out. Started using volvo stuff and have yet to have one come out. All that to say we stock volvo factory freeze plugs now and its all we use.

.

Not 100% sure until I sneak in there better later but I believe I blew a freeze plug if it's not a heater hose.... where do you aquire the Volvo freeze plugs? I definitely don't want to put a sh*t one in that will blow out on the highway since I often take long trips.
...and I don't mean long trips with cruise control on. I enjoy my long trips.
My closest dealer is 4 hours away before you say 'ask dealer' :)
 
dealers can mail them. if you blew a freeze plug out on a nearly stock setup, you've blown a headgasket as well.
 
Yea... we determined that in my thread about overboosting. Workin on replacin the head gasket soon. I would like to make sure there is no air in my system when I refill the coolant tho. Anyone know where the drain cock is? I had heat when the gasket blew on my 2 minutes ride home, now that I've refilled the system to check for leaks I noticed there is no heat. I had the car on max heat while checking for leaks to make sure it didn't overheat anything. I assume there is nothing but air in my heater core.
 
Drain petcock is on pass side of engine block under #4 clyinder exhaust port halfway down the block

Refill radiator with one gallon and run engine while pouring in the 2nd gallon helps . Make sure T Stat's "piddle valve is 100% to top/highest point when ya put the t stat in.
 
I know this thread has been down for a while now but I think we may have over looked something simple. I was looking at the design of the t stat and the over all cooling system . This is what I notice. When the t stat opens it opens to the pressurized side of the cooling system. So say a lot of pressure was to build up on the back side of it (say during a high rpm pull) I could see the t stat being held close and cause bad stuff to happen. Now I could be wrong but it seems it could be a issue. Any thoughts
 
its not really. when the t stat is closed, it circs back to the pump via the head, so when the spring heats up and the t stat opens, its opening with coolant flow, so it alsmot helps it. and them springs are pretty strong.
 
I wanted to add a couple thoughts. The metal line that runs on the exhaust side of the block-to the water pump. That thing is very close to the exhaust manifold and is seeing quite a bit of heat, is that the feed for the pump? Either way i think that could be replaced with a hose better suited to run below that hot area.Not being heat soaked by block heat and turbo exhaust manifold heat could be a good thing! The other thing is the block coolant holes in the head gaskets. I'm not a engineer, but I have opened up all the coolant ports from block to head, that the headgasket originally had blocked off or made smaller. It made things a little better, however i need to change that metal line on the exhaust side going to the water pump. My temp rises after various high boost runs over a period of time, or sitting at a traffic light after 40 minutes of driving with a/c on. I have sneaking suspicion of the metal pipe getting way too heat soaked...You can see the pipe in the picture and how it can get so hot with a exhaust manifold sitting right on top of it-especially a turbo manifold....

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I had a few questions and wanted input as well. When i get the new motor in dont want cooling issues. Setup wil be as follows. Going into 92 940. B230 8V Bored to 96.5mm. RSI Pistons. 158 MM H beams. Forged 2.5 Crank. Crank origins are stil a mystery but the best ID i have is a John parker crank. I have a 3 pulley Alum balancer.

What diamter WP pulley am i looking for? I have a 92 940 pulley in the DD. 8V head with Group A holes. Im have a .036 cometic. Slugs are poking out .006.

I bought the Roger Dee Freeze plug kit and work @ the dealer so have access to OEM plugs and tools. While i have this thing apart what else can i do to help cool it? I have a ton of heat wrap left from my brother Audi TT build and will use that to insulate that pipe on the exhaust side. I have a Ford heater core in the works for ghetto heat with heater control valve removed. Anything im missing?
 
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