Cooling system changes for high rpm use.

Chris Wilson said:

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.
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My favorite theory is harmonics but coolant pressure can vary 70-80psi from one area of a cooling system to another.

Skimmed thread to try and find a consensus - but what size water pump pulley are people using in conjunction with an underdrive crank pulley and an electric fan?

John the cap head/washer mod for the freeze plugs is a great simple solution.

gashog said:

My favorite theory is harmonics but coolant pressure can vary 70-80psi from one area of a cooling system to another.

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70 to 80 PSI?????

Stiggy Pop said:

Skimmed thread to try and find a consensus - but what size water pump pulley are people using in conjunction with an underdrive crank pulley and an electric fan?

John the cap head/washer mod for the freeze plugs is a great simple solution.

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It seems late B230 blocks they went to shallow CUP type plugs rather than the disc "saucer' type..I've seen a bit it a step for the discy saucer type to nestle up aginst, but nothing saying a little Dremel action couldn't remove thatr so the later cup type could be pounded in. and the the allen/washer dealie used.

I also believe it is block squirm..Redblocks are good but they are not the end of the world.

Is there a particular core plug that pops out? I have read of ones near motor mounts popping out in some other engines due to the stress induced during a hard standing start, especially with solid engine mounts. Solid engine mounts with a rubber gearbox mount would be a particularly bad scenario!! I am a firm believer that solid engine mounts in the typically floppy as a wet paper bag saloon car shell are asking for trouble. Engine blocks are not designed, pukka race engines in single seater applications apart, as stressed chassis members.

1) This thread is a great lesson in not believing everything you read on the internet! Lots of good stuff, and lots of absolute horsepoos. Also, lol @ Sim's only post in here.

2) This late 940 block has clearly had freeze plugs replaced presumably because they leaked (highly likely a lack of coolant = rust), or *maybe* because they blew out, non turbo vehicle.

https://twitter.com/FredCookeNZ/status/753190188176642048
https://twitter.com/FredCookeNZ/status/753190242388094980









3) I read 9 pages and no one puts a tape measure across the "big" and "small" water pump pulleys? Please can someone measure each and post what these figures are in some descriptive fashion, preferably with photos. I'll measure what I have here tomorrow morning and post some photos with this text that I'm writing now. Here we go:

Lower pulley on all four of my redblocks, two B230Fs and two B234Fs are 156mm with three grooves.
Water pump pulley on the two 1990 B234Fs is 137.8mm OD, single groove
Water pump pulley on my 1991 240 wagon B230F is 135.8mm OD, double groove (two belts)
No water pump pulley on my late 94ish squirter B230F, also headless, awaiting head from B234F...

Disclaimer, these are ODs, not comparable or useful for calculating drive ratios, just for comparing what's out there.

So, what exactly are the diameters of these two different B230F(T) pulleys? Please? Anyone? Dying to know.

4) My Mazda ute engine is making around 400hp, revs to 7300 dead stock, 8k for me, and has a cambelt driven water pump with 25 teeth and a lower sprocket with 25 teeth, giving a drive ratio of precisely 1:1. It looks like this: https://twitter.com/FredCookeNZ/status/753471917890285569 and https://twitter.com/FredCookeNZ/status/753472453725216770








OD of the impeller is 59mm and the gap between the inner edges of the folded sections is 46mm. How big are the Volvo pump impellers? Unkeen to yank one right now for various reasons.

The only cooling system issues I've had have been headgasket failure (for whatever root cause), otherwise fine. Yes, it's not relevant, but it's a data point for comparison. This vehicle has a big fat all alloy Japanese manufactured quality 50mm thick radiator built for an R32 Skyline and good for more than 500hp. The only time it's ever been warm is sitting still with no fan. Thick core = no circulation.

5) Anyone that thinks there is a constant pressure in all parts of the cooling system needs to study the concepts of pressure, flow, and restriction, repeatedly, until their eyes bleed.

5B) Anyone that thinks a gasket breach or hot spot boil up will be instantly relieved by a pressure cap several fathoms away needs to study the concept of inertia. Even air has it. Fans that blow are not the same as fans that suck.

5C) Even when the pressure cap on the header tank is wide open, it still functions as a restriction, and for large flow levels (that should not be seen in any OEM-like form) that restriction will allow a much higher pressure than intended to exist in the engine. If the engine can supply this pressure source at a rate higher than the cap can dissipate it, and nothing else releases anything, pressure will keep rising until something gives, or the supply rate equals the new higher dissipation rate, though that has a natural ceiling.

6) It's really nice to read that these engines do the cold recirculate thing, and block that passage off when they open, thanks for explaining/pointing that out, whoever did. I wish that Mazda engine of mine did this, it does not, it just blocks the flow leaving the coolant largely stagnant until it opens.

7) [New today!] So I would say a 1:1 drive would be a good thing, and shouldn't overheat at idle with an appropriate radiator and cooling fan (at least, not in my climate of mild 10-30C weather (mostly 15-25C)). Issues of "burping" are likely related to insufficient cooling capacity, insufficient flow for the heat generated, incorrect routing of flow (possibly from factory) or perhaps cavitation, but if these Volvo pumps are remotely like the Mazda one, spinning 7k with the stock "overdrive" pulleys shouldn't be a big deal IMO. I'm reminded of a video of a 1000+hp GTR RB26DET(T) engine on a dyno in Japan that vomited all of its coolant out every single run. Nothing could contain it. It generated heat so fast that it flash boiled in the head on every run. Or was it lifting the head and being pushed out by boost? Good question. Keep in mind that the insides of the head do not have massive fins for efficient heat transfer, just mostly smooth surfaces, which doesn't help. Some localised pressure and temperature logging would be a good thing to have in various spots. How much power are the problematic cars making? And how well are they put together? I can't see myself having any issues pushing 300whp from a TD05HR 16G on a 16V B230F+16V+T setup. Unless something is just plain wrong.

1230am, time to throw some rubbish in the dishwasher, scrub my teeth that I still have after a high speed road rage chase today, and head to bed. <several hours pass> <photographs and measurements inserted> <submit button pressed>

^ All lies, it's now 107am, the following day, over 24 hours later, and I'm too tired to complete this post, so I'll have to do it tomorrow. Zzzz.

Now 6pm the following day, nearly 48 hours after I wrote most of that, and I'm finally finishing up the post. 633pm, posting! Finally. Hooray. Enjoy! /me dodges tomatoes/eggs/rocks.

Not feeling overly patient tonight, I wandered down stairs and did what I said I would not, pulled a pump. GMB aftermarket variety, pressed steel blades, good condition:

https://twitter.com/FredCookeNZ/status/753484386721341440






Things different compared with the Mazda unit:

1) 70mm OD, 35mm ID, straight unswept blades, and flat block face to run against. Compared with the smaller 59mm OD, 46mm ID, swept blades and a contoured block cavity to run in: https://twitter.com/FredCookeNZ/status/753486620192485376







2) The block innards of the B230F are nasty/sharp and could benefit greatly from some radiusing with a die grinder. Even the outer edge which you'd think would be sweet is stepped and sharp.

3) The underside of the impeller doesn't have a dome to guide the fluid outward like the Mazda one does. Do factory units have a dome?

Do factory units have swept blades?



The biggest things to me are the hydrodynamics of the Volvo pump. They're not ideal for efficiency and would have a tendency to churn the water rather than move it. I look forward to being flamed for this post.

FreeEMSFred said:

I look forward to being flamed for this post.

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I would start the flaming, but it would be admitting a flawed thought process, however I read all of what I wrote and no where do I explicitly say what I was thinking, and it's all still accurate, so I can dodge this one I will say, though, the sharp edges in the block aren't an issue at all, really. They're possibly best the way they are.

The other thing I realised is that it'd be trivial to build a test rig and use a high RPM grinder to drive the pump to silly a RPM while sucking hot water from a large drum and out through a large hose back into that drum. A flat plate with a correctly sized hole and tube in the right place and you're in business. Has anyone tried this? The water would need to be hot to be a fair test, and it'd be difficult to apply pressure without inhibiting the view of the outbound flow. But it'd be indicative. Not sure if a grinder would have the guts to spin it fast enough with water in there, but it might. Larger grinders that would don't spin fast enough. Some other better electric motor might be in order. If you saw the flow drop off at some speed, you'd know what happened!

Did you really just reply to yourself about being "flamed"?

I used this item https://shop.klracing.se/sv/artiklar/-remskiva-b230-8v-3-spar-.html, to reduce rev of waterpump, and alternator. I have no problems revving 7000, no problems with cooling or charging.
Still using early B-230FT stock mechanical fan.