'New' book, interesting ideas!

Damo · Post by **Damo** » Sun Jun 03, 2012 11:25 pm

I got a copy of a fairly ordinary tuning book called 'secrets of speed', most of it is quite beginnerish and has no grasp of the 21st century, but there were a couple of different tricks which I thought may be good to try (at some stage) as they made a fair bit of sense.
The first is partial grout or epoxy filling of the block, up to 50-70 mm off the deck height (now, I realise that this would be been nessesary on a lot of American iron back in the day as they had extreamely poor block rigidity) most of the understanding of grout filling a block would be to strengthen the bores to stop them flexing and shifting with big revs, but the side benefit which I think is probably more relevant to engines which came from Japan and Europe from the 70's till mid/late 90's would be that the coolant passage through the block/head is more controlled. The portion of the block that gets filled is the lowest in temperature across the whole engine, So theoretically the coolant is kept flowing past the areas which needs cooling the most, ie the head.
Ideally, you would grout fill the block with the mains torqued to spec, and after filling whilst still liquid, torque a head to spec onto the block to ensure the block is stressed into the correct shape. After the grout has hardened for a week or so, all the machining should be done as per rebuild specs.
Theoretically, the engine would now run with less harmonics and better cooling capacity. Thoughts?

Also, there was mention of restricting coolant flow FROM the head by way of a restriction plate/cap. The idea is to pressurise the coolant in the head to around 35-40psi. I had a few dramas with this idea initially, but the more i thought about it, the more beneficial it seemed. With a standard radiator cap pressure set at around 12-15psi the boiling point of the water coolant is around 125-132c, with the extra pressure in the head, it would raise the boiling point to over 170c.
The benefit here would be areas in the head which have poor flow (#5 + #6 cylinder on RB30s jumps straight to my mind) would now have a far higher threshold against boiling. When these pockets boil and the coolant turns to steam, there becomes a big problem as the hotspot in the head now has no way of shedding the heat at all, as the trapped steam acts more as an insulator rather than a cooling medium, which makes that hot spot even hotter. This can result in particular combustion chambers running hotter than the rest, bringing on detonation earlier on those cylinders and even more passively destructive, resulting in car/engine specific combos cracking heads.

The last was crank girdles and windage trays. Both of these should be possible for the semi switched on tinkerer.

Thoughts anyone?

Also, has anyone heard of a cbr1000 head grafted to an A series engine?

Damo

Timmzy · Post by **Timmzy** » Mon Jun 04, 2012 6:15 pm

Wouldn't the grout expand and contract due to heat cycles at different rates to the cast iron? Therefore either cracking blocks or having bits of grout floating around inside block?

How much and where do they fill it>? IE 50-70mm from the deck downward inside water jackets?? That would mean NO coolant flows through the head? Or is it a simple case of re-drilling specific sized holes into the head which were obviously smaller than the original to restrict flow?

I have questions

This is operating above my knowledge - which probably isn't hard..

Darren.

Post by **shanec86** » Mon Jun 04, 2012 6:31 pm

i love you VH45... 6 bolt (cross bolted) mains + girdle

Damo · Post by **Damo** » Mon Jun 04, 2012 6:43 pm

shanec86 wrote:i love you VH45... 6 bolt (cross bolted) mains + girdle

It only has 6 bolt mains cause the block is made from plasticine!

Damo

Timmzy · Post by **Timmzy** » Mon Jun 04, 2012 7:05 pm

Bam. VH45. That'll do. Straight in the skyline

Where are they from?

Damo · Post by **Damo** » Mon Jun 04, 2012 11:18 pm

Timmzy wrote:Wouldn't the grout expand and contract due to heat cycles at different rates to the cast iron? Therefore either cracking blocks or having bits of grout floating around inside block?

How much and where do they fill it>? IE 50-70mm from the deck downward inside water jackets?? That would mean NO coolant flows through the head? Or is it a simple case of re-drilling specific sized holes into the head which were obviously smaller than the original to restrict flow?

I have questions

This is operating above my knowledge - which probably isn't hard..

Darren.

There are no dramas from dissimilar expansion. Concrete .0108mm/mtr per k, steel .0130mm/mtr and cast iron .0100mm/mtr all have similar expansion rates per deg c. So if concrete is used, you would get something in the order of .05mm difference in expansion across the length on the block at 100deg which is negligible. Concrete become water proof when it goes off too.

The grout (or epoxy) mix is poured into the water galleries to fill the lower section of the block. The bloke suggests between 40-45% of the capacity of the water jackets of the block, up to or even beyond the welsh plugs. Just need to be aware of where the water pump sits, and possibly making up a blanking plug to keep the cavity for the pump clear including the passages from it to the upper section of the block. So coolant still flows through the head as it should.

One other thing to keep in mind is not to do this while the engine is on a engine stand, you don't want the block flexing, then the cement hardening in a flexed block! Also, the water galleries must be cleaned really well with caustic soda soaking mix for 24hrs, then dried and cleaned with compressed air, followed by cleaning with brake cleaner or thinners.

I did a little research on the net, there seems to be a bit of info floating around regarding it.

Damo

Callumgw · Post by **Callumgw** » Tue Jun 05, 2012 7:45 am

surely if you fill all the holes you reduce the surface area nd therefore reduce the passive cooling......

C

Damo · Post by **Damo** » Tue Jun 05, 2012 9:51 am

Callumgw wrote:surely if you fill all the holes you reduce the surface area nd therefore reduce the passive cooling......

C

That's right, but you are only filling the lower portion of the block which is over cooled compared to the rest of the block head combo anyway. So, this should actually have the lower portion of the block run closer in temp to the upper section of the block which would aid in maintaining correct piston/ring gap lowering blowby past the rings.

Damo

Post by **shanec86** » Tue Jun 05, 2012 5:15 pm

don't be jealous of my collection of nissan V8's damo

Damo · Post by **Damo** » Tue Jun 05, 2012 9:33 pm

Timmzy wrote:Bam. VH45. That'll do. Straight in the skyline

Where are they from?

Infiniti's.

Damo

Timmzy · Post by **Timmzy** » Tue Jun 05, 2012 11:33 pm

Damo - thanks mate. I didn't know that.

Also thanks for the reading.

Is that why some head gaskets have some of the block water jackets positions covered, even though there is a corresponding hole in the head matching to it>

Darren.

Damo · Post by **Damo** » Wed Jun 06, 2012 3:50 pm

Timmzy wrote:Damo - thanks mate. I didn't know that.

Also thanks for the reading.

Is that why some head gaskets have some of the block water jackets positions covered, even though there is a corresponding hole in the head matching to it>

Darren.

You will find that the first generation e13/15 will have a original gasket which has all the holes open for coolant flow, and the later the engine was assembled, the more coolant passages were blocked off in the gasket to control coolant flow through the head. Nissan probably became aware of certain trends in engine failures and implemented a fix. I would hazzard a guess that if you were to have a bunch of E series heads upside down, you could pick the order they appeared on the domestic scene by the amount and size of coolant passages.
You have probably seen this yourself in the differences between the OE head gasket and any replacement you have installed.

Damo