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Cooling system changes for high rpm use.

Move the water pipe after the water pump, either make a hose or weld a different angle on it so its not so close to exhaust manifold. Smallest diameter water pump pulley?
 
Hi

I have never heard anyone here in Finland who would have popped freeze plugs out by high revving/heat. Do you use proper antifreeze liquids? There's plenty of people who have 500-800 hp engines and still never heard of this issue...

-Joikale-
 
There's also a thing that proper antifreese liquids do, it won't let things get corroded, bad thing is corrosion fills radiators and that really does not help with cooling. It also lifts boiling point of liquid so there will be less pressure problems.

One guy whom I bought a brass volvo 140 radiator told me that clean radiator filled up with water will completely drain in about 10 secs, if it takes longer it's blocked. And that guy fixes radiators for living...

My friend told that he knows couple of cases of freeze plugs popping out due ****ty antifreeze liquids.

I do not know but I think you're just wasting your money on smaller/bigger pulleys or antifreeze plug kits, just use proper liquids.

Just my thoughts...

-Joikale-
 
i may be overthinking this but, if block vibration/squirming whatever you want to call it is contributing to this as previously suggested. would it not be worth while trying to strengthen/brace the weaker areas of the block eg around core plug height etc. or by way of vibration dampening? just a thought :e-shrug:
 
i may be overthinking this but, if block vibration/squirming whatever you want to call it is contributing to this as previously suggested. would it not be worth while trying to strengthen/brace the weaker areas of the block eg around core plug height etc. or by way of vibration dampening? just a thought :e-shrug:

I think a lot of vibrations come from the motor not being 'perfectly' balanced. ie the rods, pistons, and even their bolts arent exactly matched in weight.
 
I still don't belive that to be the problem in the 400 whp range. These things seem to be messing up on the way down from high rpm not on the way up. Also these seems to be out going pressue that finds the weakest link such as heater core or radiator.
 
Sound like a bad head, gasket, or broken Pistons that are creating enough pressure to pop the plugs out..I would do a compression check? Lots of pages in this thread I only read a few.. Has it been done yet?
 
Something is building pressure somewhere it's not supposed to and I bet it is not due to the size of the coolant chAmbers, do you run an e-fan? Is it blowing the correct direction, is the thermostat frozen, how's the heater core is it leaking? There's a lot of e-fans people use without thinking first. I learned my lesson and put the stock fan back on my car. Sure I have lost a lil bit of pep but at what expense? A cool running motor? ....I'll take that any day of the week
 
Tight

Olov.....would take some time to figure which plug had the pressure. When mine failed the first time....I lost the rear 2 on exhaust and forward on the intake side. There were 3 others that were flush with the block and not even with the chamfer. You have a good idea about tapping the block....but from what I'm seeing...the bores are very close to the plugs so you'd almost need to start the hole...the cut the die up and finish tapping. And with my engine installed....a bit more work than what I wanted. And the valve is only 3/8 pipe.....any larger and the solenoids get huge.

I was thinking, is it allways the plug that is at the place where the cilynder wall is at the closest of the outside wall, sort of "tight squish" so to say.

It could explain some issues imho.
 
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Maybe the correct pattern of flow is to be questioned here. A lot of us are too lazy to tackle a leaking heater core, and as a result have Looped the metal feed line from water pump, to the back of the head on cylinder 4 ( 16 valve head or 8v). Maybe, instead, these two lines should be capped off from each other instead of looped? As in the regular operation of a heater valve. Open valve, water goes through heater core, cools a bit, then back to cylinder 4. Closed valve, no flow to cylinder 4. No super heated heat soak in cylinder 4. Infra red temp gun shows anywhere from 10, to 20 degrees hotter from the head above cylinder 4 versus the always lower cylinder 1 With looped heater hose.
 
Harmonic balancer

About the blown out freeze plugs it is also my believe that in the case of underdrive pulley's this gould be the culprit. That "thing" is a harmonic balancer with the rubber ring in it. When you take that away it can cause abnormal warping or even brake your crankshaft. (Nathan did in the beginning, I think he had an underdrive pulley).

By the way, why do I read so little about drilling the 5 extra water hole's like the Folkracing guy's do (in case of the 8v). It's done in half an hour and when properly (the right hole sizes) the flow is much more "equal".
I did it and it works, no HG and temp problems so far (fingers crossed).
 
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There's no way at all water pressure will blow core plugs, anything like the sort of pressure needed would blow the rad apart, or blow a hose. To me it smacks of block squirm. Even the Motorsport Cossie Sierra blocks would pee oil out of the rear main seal if they were true 500 BHP plus motors used on a circuit with a LOT of boost for sustained periods. Block movement could be sufficient to allow core plugs to move, for sure, on weak blocks used well over their design limits. The Sierra blocks always seemed to have tiny cap heads and washers in either opposing pairs or even tripled around the periphery of each core plug, as well as using Loctite hydraulic seal on them. Whether there had been an issue with plugs coming out, or it was just good belt and braces engineering practice I don't know, I ran N/A converted ones with nothing like the same cylinder pressures or torque capability.The few serious turbo Sierra engines used in circuit work here in the UK were always wet at the back end, and I was always told that block squirm, even on the Motorsport heavy duty castings, was the cause.

In the early days of the Cossie Sierra in competition they had head gasket issues and used to pre pressurise the cooling system to try and help them through a race. They ran special rads and hoses to withstand this coolant system pressure, but I never heard of them popping core plugs. I think they may have gone to Reinz gas filled rings later.

Has anyone any photos of a red block band sawed open, width wise and longitudinally? It would be interesting to see where the material was, and was not!

I do this to heads that are new to me, to see where one might hit fresh air or water before porting a good or new casting. For years people in the UK used to say you must not remove the hump in the exhaust ports on Nissan RB26DETT heads, as you'd be into water. I got a scrap head and band sawed it up. The talk was rubbish, the water was miles away. No one had done this before in the UK and people seemed amazed anyone would want to do this. The head was scrap value with a dropped valve.... Go figure!
 
There's no way at all water pressure will blow core plugs, anything like the sort of pressure needed would blow the rad apart, or blow a hose. To me it smacks of block squirm. Even the Motorsport Cossie Sierra blocks would pee oil out of the rear main seal if they were true 500 BHP plus motors used on a circuit with a LOT of boost for sustained periods. Block movement could be sufficient to allow core plugs to move, for sure, on weak blocks used well over their design limits. The Sierra blocks always seemed to have tiny cap heads and washers in either opposing pairs or even tripled around the periphery of each core plug, as well as using Loctite hydraulic seal on them. Whether there had been an issue with plugs coming out, or it was just good belt and braces engineering practice I don't know, I ran N/A converted ones with nothing like the same cylinder pressures or torque capability.The few serious turbo Sierra engines used in circuit work here in the UK were always wet at the back end, and I was always told that block squirm, even on the Motorsport heavy duty castings, was the cause.

In the early days of the Cossie Sierra in competition they had head gasket issues and used to pre pressurise the cooling system to try and help them through a race. They ran special rads and hoses to withstand this coolant system pressure, but I never heard of them popping core plugs. I think they may have gone to Reinz gas filled rings later.

Has anyone any photos of a red block band sawed open, width wise and longitudinally? It would be interesting to see where the material was, and was not!

I do this to heads that are new to me, to see where one might hit fresh air or water before porting a good or new casting. For years people in the UK used to say you must not remove the hump in the exhaust ports on Nissan RB26DETT heads, as you'd be into water. I got a scrap head and band sawed it up. The talk was rubbish, the water was miles away. No one had done this before in the UK and people seemed amazed anyone would want to do this. The head was scrap value with a dropped valve.... Go figure!
 
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