16 replies to this topic

[WoodyWagon]

I have a blanking sleeve to install and am a bit unsure regarding its fit.

I have an SC 7 port head and have noticed that the flow holes in the head are in a different locations than a stock head. They seem closer together.

Am I correct in assuming that the holes in the sleeve are supposed to line up to the two holes within the cylinder head. If so I think I need to drill a new hole for it to line up. Does this seem correct or reasonable

[Retroman]

Ask SC they will know

[nicklouse]

holes aligning? no idea what you are on about.

[WoodyWagon]

I thought that the holes in the sleeve aligned to the water jacket holes in the head, where the white arrow is and the other one to the left. On the SC head those water jacket cutouts are much closer together.

Am I wrong and the sleeve just pops in any old direction.

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[Spider]

Is this for a road or track car?

[nicklouse]

when i used to use one. i dont not as it used to take way too long to get the engine up to temp i just slapped them in any old way as they never came with any fitting info. and i could not see the purpose of the holes other that to possibly let some air out of the engine but then i would like them much higher up to the mating surface. 

 

have a thermostat in mine now as the blanking sleeve was only really produced when thermostats had a habit if failing.

[WoodyWagon]

It's a road car but the motor is pretty much full race prep'd. It also only sees summer driving

[WoodyWagon]

I'm sure that the holes are what helps create some pressure, without some restrictions there wouldnt be much pressure and the back of the head won't circulate. That why I thought these need to align with the water jacket holes?

Edited by WoodyWagon, 14 July 2018 - 07:53 PM.

[Orange-Phantom]

A simple solution to your problem would be to run a thermostat. As Nicklouse has said it will take an age for your engine to get up to temperature. Once it eventually gets up to temperature (if it actually does) it won't improve the cooling.
I run an 82 thermostat and I've got a 7 port head and all the trimmings and I never have any issues with overheating. My brother builds race winning engines and he always fits a thermostat too. He would never build an engine with a blanking sleeve.
Basically you really should be running a thermostat.

[nicklouse]

It's a road car but the motor is pretty much full race prep'd. It also only sees summer driving

so why do you think you need one?

[Spider]

I'd run a thermostat without a second thought.

 

It will allow you to get the engine to the right operating temp and importantly, give temperature stability as well. Being an alloy head, it would reach better power when hotter than colder.

 

The original idea of the blanking sleeve was for competition conditions where (obviously) a failed thermostat could cost a race, but I gotta say, I don't ever recall seeing one that has failed.

[whistler]

I'd run a thermostat without a second thought.
 
It will allow you to get the engine to the right operating temp and importantly, give temperature stability as well. Being an alloy head, it would reach better power when hotter than colder.
 
The original idea of the blanking sleeve was for competition conditions where (obviously) a failed thermostat could cost a race, but I gotta say, I don't ever recall seeing one that has failed.

[WoodyWagon]

This whole thing was started by a what I thought was a failed thermostat. Suddenly I couldn't even get my car down the street before its overheating. After cracking the top rad hose and finding it dry I presumed a stuck thermostat.

[nicklouse]

if you rad was dry then you have a leak somewhere. or the rad cap is not right for the rad and is letting the coolant out.

[gazza82]

On most 'moderns' the thermostats stick open ...