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leadfoot · Posted: Wed Mar 21, 2012 10:16 am Post subject:

Yeah it's been a while since I did my mod, I always gauged it on the look of the spark plug in number 4 compared to the rest,
Also going to mod the outlet to 32mm, and incorporate the stock sensors into it
BTW nice work on the car,
Stu
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

daveo · Joined: 02 Sep 2005 Posts: 183 Location: GB

on our race cars we run a second cooler from the back of the block to help plus i run a electric water pump and normal impela to boost water flow, we lost a motor 2 year back and pikup was grater on no4
( the electric pump helps when bleading air out of the cooling )

WEASEL149 · Joined: 19 Aug 2005 Posts: 595 Location: UK, Sheffield

daveo · Joined: 02 Sep 2005 Posts: 183 Location: GB

hi
ok the electric pump comes of the botom out let pipe on the standard rad then gets fed into the impela inter pipe (sits in the midle)
the first motor had the porsche impela removed and blanked (coped) off, (not my doing) but this was not a good way to do things as the water being pumped from the elec pump was not flowing right as it was trying to go in two directions at the same time, into the block and up out of the old impela housing at the same time. staling water flow, this cost me the Dave Denet motor with the stroker kit he made, as the race was 45 minuts it just burnt out (and some other problems)
so we put the old impela back to get flow in the right direction
as for the second rad just loop it of the back of the head like a second heater matrix (if its a road car) and drop it into a cool air flow, or put a small fan on the second rad to save on cooling pipe going all the way to the front of the car then back
hope this helps,

simsport · Joined: 06 Nov 2002 Posts: 573 Location: UK Warrington

Its interesting this thing about flow when the pump casing is used . I looked at how the pump worked and figured it 'pulls' water from the rad via the standard impellor which is just a little bit inset into the face of the block.

The impellor is actually inboard of the thermostat and so 'blows' the water into the block from the rad whilst aslo pulling water when the stat is closed. For that reason you have to blank off the lower stat port when not using the standard pump and are using an electric pump which of course pressurises the full original pump housing.

Cheers
Simon
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Blown is always best!