Harrop 2300 supercharger to Optimiser 6500

[MB]

.......maybe raise the trailing edge of the hood to see if letting out the heat would drop the temps.

I'll check with the powertrain boys at work to see what they think, but to me thats seems high

G’day Ralph Mate!
Was kindly educated by some TD42 (very similar donk heat characteristics) Legends on here years ago that this is not the ADR-Roads legal answer :-) ?
Certainly proven to me at higher engine bay pressure needed speeds and was personally in the middle of slower speed tests with another 6.5 Manometer owner until he unfortunately moved on from here.
I do now have a ‘Blitz’ ADR compliant bonnet with slimline very very forward/front slits that works wonders on the highway assisting shoveling engine bay heat downwards/rearwards out below but do still wonder at slower speeds if it’s hindering my electrical fans pressurising the engine bay down and safely windscreen out!
Aim of the game as I understand is to get that hot shit out down low and away from all our up top good bits like your Superchargers?
By far the greatest ‘hot bits’ in our 6.5 V8 crammed GU & GQ conversions are the down low exhaust manifolds left/right firewall near touching and in my nuffy opinion the Powertrain Legends might agree that the fastest route out is below & backwards?

PS: Would it be fair to say that some TD42’s with giant top mount intercooler bonnet scoops run hotter overall at lower lugging speeds maybe?

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[Winnie]

PS: Would it be fair to say that some TD42’s with giant top mount intercooler bonnet scoops run hotter overall at lower lugging speeds maybe?

I'm not sure about that. I have the cross country top mount with the big scoop and have never had an issue with temps at low speeds. I've actually wondered whether it runs too low at slow speeds.
When pushing it at high speeds and towing I do have to keep a little eye on the temps on hot days.

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[MB]

Cheers Chrisso Mate, do you have an electrical fan on the IC to stop the hot air rising back through it when pushing hard up slow climbs?


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[Winnie]

Cheers Chrisso Mate, do you have an electrical fan on the IC to stop the hot air rising back through it when pushing hard up slow climbs?


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Yes I do, no idea if it works/how well it works because it's been on the whole time the cooler has been on so can't compare without it.

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[MB]

Awesome, this could be a perfect test opportunity Chrisso
Unplug the elecy fan and do a second identical hill climb to measure EGT’s again for starters maybe?
Could always shove your BBQ temp probe into the engine bay rear upper area too?


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[poindexter]

G’day Ralph Mate!
Was kindly educated by some TD42 (very similar donk heat characteristics) Legends on here years ago that this is not the ADR-Roads legal answer :-) ?
Certainly proven to me at higher engine bay pressure needed speeds and was personally in the middle of slower speed tests with another 6.5 Manometer owner until he unfortunately moved on from here.
I do now have a ‘Blitz’ ADR compliant bonnet with slimline very very forward/front slits that works wonders on the highway assisting shoveling engine bay heat downwards/rearwards out below but do still wonder at slower speeds if it’s hindering my electrical fans pressurising the engine bay down and safely windscreen out!
Aim of the game as I understand is to get that hot shit out down low and away from all our up top good bits like your Superchargers?
By far the greatest ‘hot bits’ in our 6.5 V8 crammed GU & GQ conversions are the down low exhaust manifolds left/right firewall near touching and in my nuffy opinion the Powertrain Legends might agree that the fastest route out is below & backwards?

PS: Would it be fair to say that some TD42’s with giant top mount intercooler bonnet scoops run hotter overall at lower lugging speeds maybe?

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Under hood heat is quite an issue on some vehicles, when I was working at GM, the issue we had with the Commodore, the trans tunnel was so full that no air flow would occur, and the engine bay sides were sealed for drive by noise compliance, therefore, getting the air out was quite a problem.

Bringing this back to the Patrol, I'm not a fan of exiting the air downward.
At low speed exiting the air downward is problematic as heat will tend to rise, and vehicle speed may not be sufficient to push is down and out, plus you may be axle deep in "stuff". Thats why there are raised trailing edge hoods.
I'm currently looking at a passive solution that will allow the hot air to exit through a low pressure area on the hood, so that it will be effective at both low and high vehicle speeds.
If I can find the time over the Christmas break I hope to post some details, on my progress.

[PeeBee]

I have ordered the 2 bilge blowers, 3" diameter and will play around with these to begin with. The spacing of the bonnet even by 3mm will make a difference, and as long as its not obtrusive I may get away with it. Might start with 3mm then move to 6mm. thanks for the thoughts guys. I had gills in my bonnet as you might remember @MB and whilst they emitted a heap of heat at low speed, stationary, the vehicle still hit 125degC on one occasion on that Hi Cone trip - after the long low range climb thru Darrens ' regrowth track. The point I am making is that natural venting was not sufficient to remove the heat. If I stir the air up and provide a physical high level gap for it to escape, the air volume will be displaced/replaced. Thats the theory anyway.

I will try to direct airflow towards the exhaust manifolds for sure on the basis i can push what i can out the bottom and what is rising out the windscreen gap.

[poindexter]

OK, had a conversation with the powertrain engineers about the under hood temps.
The consensus is that 65c is what is seen during Camaro ZL1 dyno runs, and that is what a "running" vehicle should be at,however, with heat soak goes up to 85c +.
The engineer thought that fans directed over the exhaust and exiting under the vehicle sounds like a solution, that is, if you can't vent through the hood (the Camaro has this hood venting)
All under hood plastics are generally rated to 140c from the factory. After market stuff (read Chinese) may not be so rated.
This is quite interesting, as I now have a hood without a scoop, and was not planing to add vents. So, active underhood venting may be a plan.....

[PeeBee]

OK, had a conversation with the powertrain engineers about the under hood temps.
The consensus is that 65c is what is seen during Camaro ZL1 dyno runs, and that is what a "running" vehicle should be at,however, with heat soak goes up to 85c +.
The engineer thought that fans directed over the exhaust and exiting under the vehicle sounds like a solution, that is, if you can't vent through the hood (the Camaro has this hood venting)
All under hood plastics are generally rated to 140c from the factory. After market stuff (read Chinese) may not be so rated.
This is quite interesting, as I now have a hood without a scoop, and was not planing to add vents. So, active underhood venting may be a plan.....

Thanks ralph, I have installed and wired up 2 off 100cfm bilge blowers generally directing air towards the exhaust headers. The rear of the bonnet is raised 10mm, and removed the rubber weather seal to allow a full flow condition at the windscreen. Once i have the bonnet catch resolved i will take it for a blast and report back. I do have a third 3" blower that I am thinking of mounting up higher in the bonnet area to stir up the upper air - just a thought at this time.

[PeeBee]

OK, update time.
Marks4x4 5th gear. Pre install 1925rpm at 100khr, now smack on 1600. Fuel now down to 15 - 17l/100, pretty damn happy, and sink the boot in 5th and off he goes. Whether this is the sweet spot or not for economy, don't care, it works.

Rear Coil replacement - booked a workshop fit with Dobinsons in Dandenong - highly recommend this, system they employ is great and service spectacular, workshop guys friendly knowledgeable and solution seeker/providers. The weighed the car on each corner first, took the measurements with the airbags inflated and deflated, then whilst the guys removed the coils they ran the numbers, and two coils came up, both XHD GU coils - they don't rate the GQ coils as a product line any more but GU are interchangeable.
The target was a 40mm lift over standard and use the BOSS triple airbags for level trim. The coil are 1mm dia thicker and 75mm higher thanthe ones removed. Coil number is C45-325T, 250-350kg constant rate coil. The originals were a 400kg variable rate coil, and they sagged within 9 months of installation. These ones sit the car slightly up at the rear, but does not look crazy. This is without the airbags inflated. Rides well, still top heavy so can get a bit of a wander on curves at speed. Happy with outcome.New Coils.JPG