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pulsarboby
Guest
dont think your gonna find any info on that car tbh as its all done by his own team i believe. and in all honesty whos to say hes not having probs after every event!!!
your missing the point there karl, what im saying is that if the waterjacket is too small then no matter what you do to it ie, by forcing air, big rad, electric pumps bigger fans etc the jacket will only flow so much coolant unless it can somehow be opened up to make a better flow!
now im not saying that all the ideas people have come up with wont help but it seems they are merely masking what could be the main issue, which is what im trying to get to the heart of in order to keep temps down throughout the head and block and thus eleviate any potential hotspots which is what i believe to be the real damaging factor.
hotspots are very bad for an engine especially one running high power, and obviously the faster you go and at constant wot these are gonna be causing a whole heap of trouble
longshot here but has anyone got access to a thermal imaging camera??? thats whats needed to try find the hotspots
your missing the point there karl, what im saying is that if the waterjacket is too small then no matter what you do to it ie, by forcing air, big rad, electric pumps bigger fans etc the jacket will only flow so much coolant unless it can somehow be opened up to make a better flow!
now im not saying that all the ideas people have come up with wont help but it seems they are merely masking what could be the main issue, which is what im trying to get to the heart of in order to keep temps down throughout the head and block and thus eleviate any potential hotspots which is what i believe to be the real damaging factor.
hotspots are very bad for an engine especially one running high power, and obviously the faster you go and at constant wot these are gonna be causing a whole heap of trouble
longshot here but has anyone got access to a thermal imaging camera??? thats whats needed to try find the hotspots
Have a read of this.
http://www.sr20forum.com/general-sr20/187033-sr20-cnc-combustion-chamber-3.html
Some highlights are ...
Nissan probably reduced the quench on the 54C motor to reduce compression to 8.3:1 in a quick and dirty way. SR's are prone to detonate but I bleive its due to poor water circulation in the head due to a horrible water pump and poorly thought out water flow path throught the head in addtion to a poorly designed water passage system in the head with lots of core shift and insufficent water volume.
The last varient of the SR, the SR20VE 20V and the SR20VET have drasticaly different cooling passages in the head and a lot more water around the combustion chambers, which leads me to belive that they were attempting to recitivfy the problem.
and
ways to address the cooling of the head. I really underdrive the water pumps pulley, the pumps flow stops at 6500 rpm due to super bad caviatition, when I says stops, it really goes to ZERO. I also limit the bypass to the thermostat with a restrictor to force most of the coolant to flow back to the radiator, if you don't do this, the coolent flows round and around and never leaves the head. I also add an external bleed to the higher part of the thermostat housing and radiator and plumb it to a high mounted swirl pot with the bottom of the pot, tapped to a -4 line going to the suction side of the water pump. This purges all air out of the head.
I am also starting to experiment with 400 degree boiling point evans coolant.
http://www.sr20forum.com/general-sr20/187033-sr20-cnc-combustion-chamber-3.html
Some highlights are ...
Nissan probably reduced the quench on the 54C motor to reduce compression to 8.3:1 in a quick and dirty way. SR's are prone to detonate but I bleive its due to poor water circulation in the head due to a horrible water pump and poorly thought out water flow path throught the head in addtion to a poorly designed water passage system in the head with lots of core shift and insufficent water volume.
The last varient of the SR, the SR20VE 20V and the SR20VET have drasticaly different cooling passages in the head and a lot more water around the combustion chambers, which leads me to belive that they were attempting to recitivfy the problem.
and
ways to address the cooling of the head. I really underdrive the water pumps pulley, the pumps flow stops at 6500 rpm due to super bad caviatition, when I says stops, it really goes to ZERO. I also limit the bypass to the thermostat with a restrictor to force most of the coolant to flow back to the radiator, if you don't do this, the coolent flows round and around and never leaves the head. I also add an external bleed to the higher part of the thermostat housing and radiator and plumb it to a high mounted swirl pot with the bottom of the pot, tapped to a -4 line going to the suction side of the water pump. This purges all air out of the head.
I am also starting to experiment with 400 degree boiling point evans coolant.
Trip
New Member
If i understand right, Flatspots is the lack of cooling certain areas of the engine, making some spots cooler and some hot. This heat difference within the same lump will cause distortion/warping. (whoever is into welding, this is very evident when a piece of metal is heated unevenly.)
The problem of flatspots is not related to the in-efficiency to cool the water before entering the engine. Massive oversized radaitor, shrouds and channeling fresh air to radiator will not help. The red Pulsar in Japn is running a rear radiator, which i assume is less efficient than a front mount.
Wouldn't it be worse if we lowered (cooler) the temperature (by using a more efficient radaitor) and not addressing the hotspots ??? this would create a more uneven heat temp difference within.
my €0.02
The problem of flatspots is not related to the in-efficiency to cool the water before entering the engine. Massive oversized radaitor, shrouds and channeling fresh air to radiator will not help. The red Pulsar in Japn is running a rear radiator, which i assume is less efficient than a front mount.
Wouldn't it be worse if we lowered (cooler) the temperature (by using a more efficient radaitor) and not addressing the hotspots ??? this would create a more uneven heat temp difference within.
my €0.02
That makes sense Trip; it's not a matter of getting the coolant cooler... it's a matter of getting the coolant where it's needed.
If someone sits-down and has a think about it; there's probably a way to make sure the coolant flows everywhere at an acceptable rate, but it may involve a bit of re-plumbing and check-valves so that the coolant path is one way.
If someone sits-down and has a think about it; there's probably a way to make sure the coolant flows everywhere at an acceptable rate, but it may involve a bit of re-plumbing and check-valves so that the coolant path is one way.
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pulsarboby
Guest
it seems that no one has yet tried this! thats a quote taken from that forum, bloody good read that btw so thanks for finding it gtir350
as said the pump bit is sorted and as for cooling well ive got that in abundance
im gonna crack a head and block wide open with an angle grinder and see for myself where these hotspots are likely to be then see if i can do something about opening the things up where there are known restrictions.
i bet somebody has attempted it in the past (its not new technology afterall, but i cant find a damn thing on it so its all gonna have to be a bit of guesswork) but if it works then im sure i could build a much more reliable track car than ive got at the mo. im not gunning for huge power just something that can handle between 350-400 reliably event after event without having to keep ripping the thing apart to make repairs due to poor water circulation causing all the dreaded issues that go with it.
the high boiling point coolant sounds very interesting too
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mynheers_a_pint
Guest
are you still using the Radtec set up?
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pulsarboby
Guest
no thats gone liam, i reverted back to a 52mm core rad.
Good subject this!!!!
Just wondering whether it's worth running an old engine on a test-bed to desruction (in relation to the subject of course) and then seeing where it's all gone wrong?!?!
A note to add, I believe the VE head is the variable-valve-timing head and to my knowledge, it's not a very good system (the one installed on the 200sx S14a anyway). Therefore, if the the VE head has better circulation, can the standard R head be modified to avoid the VVT?
My thoughts on this are to approach the 'cooling' of the R's engine from three different angles; water, oil and air. Water being the previous comments and points concentrating on increased volume of water and it's efficiency flowing through the system. Oil being very similar to water. Air being general air-flow around the engine, engine-bay and through cooling vessesls. The R has a compact engine-bay which is rammed with parts, I suppose this doesn't allow for good, even air-flow.
Keep-up the good work everybody!
Just wondering whether it's worth running an old engine on a test-bed to desruction (in relation to the subject of course) and then seeing where it's all gone wrong?!?!
A note to add, I believe the VE head is the variable-valve-timing head and to my knowledge, it's not a very good system (the one installed on the 200sx S14a anyway). Therefore, if the the VE head has better circulation, can the standard R head be modified to avoid the VVT?
My thoughts on this are to approach the 'cooling' of the R's engine from three different angles; water, oil and air. Water being the previous comments and points concentrating on increased volume of water and it's efficiency flowing through the system. Oil being very similar to water. Air being general air-flow around the engine, engine-bay and through cooling vessesls. The R has a compact engine-bay which is rammed with parts, I suppose this doesn't allow for good, even air-flow.
Keep-up the good work everybody!
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pulsarboby
Guest
yeah as said on the dog n bone today russ, the ve head wont mate with the block of a gtir but guess nothings impossible lol, just out of my league with all the work that would be involved
i dont really know what to do so im gonna cut loose with a dremmel type tool and take around 1mm off each waterway opening in head then match it to water jacket in block, then try smooth out as much of the casting that i can get at
dont know whether it will make things better or worse tbh, but hey nothing ventured nothing gained as they say:lol::lol: if it works then il be over the moon.
if it prematurely goes boooooom! then out comes my big hammer:twisted:
i dont really know what to do so im gonna cut loose with a dremmel type tool and take around 1mm off each waterway opening in head then match it to water jacket in block, then try smooth out as much of the casting that i can get at
dont know whether it will make things better or worse tbh, but hey nothing ventured nothing gained as they say:lol::lol: if it works then il be over the moon.
if it prematurely goes boooooom! then out comes my big hammer:twisted:
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pulsarboby
Guest
i cant think of a way ev, and it appears theres no info on this anywhere so guess it will just have to be trial and error.
i bet someone has done it before but trying to find who and how much they removed is a tricky job lol.
providing i dont go to mad with the grinding tools i cant see that i can make it much worse, you never know it may even actually work:shock::lol:
i bet someone has done it before but trying to find who and how much they removed is a tricky job lol.
providing i dont go to mad with the grinding tools i cant see that i can make it much worse, you never know it may even actually work:shock::lol:
Trip
New Member
I don't know maybe there are some kind of probes "Sticker like" you can stick to different places and monitor the difference. Or the IR tyre temperature reader
http://www.gadgetsngift.co.uk/Store...emDetail.aspx?sfid=84646&c=418328&i=231957911
I would maybe discuss this with a reputable tuner who has good expereince with the SR enigines + other makes and compare the cooling vessels, tollerances between different makes. You would want to go larger but not too large to weaken the head/block.
http://www.gadgetsngift.co.uk/Store...emDetail.aspx?sfid=84646&c=418328&i=231957911
I would maybe discuss this with a reputable tuner who has good expereince with the SR enigines + other makes and compare the cooling vessels, tollerances between different makes. You would want to go larger but not too large to weaken the head/block.
R
riske
Guest
I vote trial and error!! You have been doing it all this time so dont stop now! Might as well do little bits at a time and see how it goes. No harm in trying. You could be a pioneer in fixing this infamous problem with the R. Go on!!!
red reading
Active Member
ditch the standard water pump and fit the electrical version and use external lines to modify the coolant path as there are plenty of core plugs on the 54c block to tap into (i.e make threaded fitting's up and tap the core plug holes ),keith cowie has this on his skyline.
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pulsarboby
Guest
will need to speak to you about this danny, il give you a shout when my lashup engines blown up (which shouldnt be too long) although having said that it may last a while you never know with these bl00dy cars:lol:
gotta talk to you anyway about you know what!
gotta talk to you anyway about you know what!
Trip
New Member
Interesting..