Coil packs under the intake manifold

[minorv8]

I am (slowly) making a new plenum for my next engine. My current setup has the coil packs mounted on the firewall just behind the intake manifold. This is not perfect location, especially when I need to remove the engine. With the new intake there will be even less space. I have been thinking about mounting the coil packs underneath the plenum since there is plenty of space.

Now, the question is would there be any ill effects, e.g due to heat from the engine ? My engine room is crowded enough so finding a better location is a bit challenging.

I'll upload some photos once I have them reduced in proper size.

[88v8]

The two prime causes of coil failure... vibration, heat.
Custom cars, with a clean engine bay, presumably mount them in the cabin.

Use the space under the plenum for other purposes.
https://www.wikihow.com/Cook-Food-on-Your-Car%27s-Engine

Ivor

[minorv8]

This is what my plenum will look like. I am still thinking which throttle body to fit. I currently have a 75 mm Mustang throttle body (chinese knockoff) but its linkage does not fit my plenum design. I need to get creative with the thermostat housing as well.



Here is a single coil pack stashed underneath the plenum for demostration purposes. This is a injection Mini coil, the Bosch coil packs I have are a touch smaller.

TVR AJP V8 have the coil packs in the lifter valley and in a very tight space. I doubt that my setup would be that bad. Factory LS coils are mounted to the valve covers and they see a fair amount of heat and vibration too.

[BlownMGB-V8]

Pretty big plenum. Will that cause any problems?

You should be able to get by with putting the coils there if you allow some airflow through the area I would think.

Jim

[Blown v8]

I'm thinking of putting mine on the block,under the headers, plenty of room,plenty of airflow, headers will be cam coated to help,
And it'll keep the leads short, and clean looking.

[minorv8]

Jim, there are trumpets inside the plenum but yes it is a bit big. The manifold runners kind of dictated the design. I hope that the engine size will help some (5+ litres).

[DiDueColpi]

I don't see any problems with placing the coil packs under the plenum Jukka.
Almost every COP engine places their coils in the hottest place on earth and then covers them up with some pretty plastic to make sure that they are miserable.
They seem to last just fine.
Cheers
Fred

[MGBV8]

Great to see you back, Fred!  We were worried about you.

[minorv8]

OK, thanks Fred. I just need to fabricate a bracket for the coil packs. There is a photo of my thermostat housing that I welded together from some scrap laying around. There are bungs for an EFi coolant temp sender and a mechanical temp gauge.

[Bland]

What ECU will you be running?.  I need to build a thermostat housing similar to yours for my ITB manifold.

[minorv8]

I have a Haltech E6X, been running that for a couple of years.