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Discussion Starter · #21 ·
This is the design for the coil bracket I've come up with. Anybody have thoughts/critique on this?



The outboard holes are 0.62", which is to accomodate the rubber grommet mounting eyelets the plate will be fastened to - which will be coaxial with the valve cover bolts.

The holes to mount the coils themselves to the plate are 0.13". These holes will need to be drilled/tapped, which the laser-cut process can't achieve, so the 0.13 holes are there so I can easily just drill them out for the M6x1 tap.
 

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Is there a reason why you went so thin around the outside of the coil pack holes? I would imagine this will vibrate a lot and destroy the packs over time.

Can you not brace it a bit like the image below? Im a belts and braces designer though so lol
Automotive exterior Mode of transport Font Rectangle Automotive tire
 

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Discussion Starter · #23 · (Edited)
No particular reason aside from having spent a lot of time with racecars and avoiding unnecessary material/weight as much as possible - and the bracket I took inspiration from didn't have it either:


There are 8 mounting points, and only about a 6.5" span between them - plus it'll be mounted in rubber grommets (using the same ones Mercury Marine used on their coil bracket for isolation from vibration)
 

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As I have not really read much into the particular coils you want use, will GM truck coils not work? The LQ9 coils are great and there are brackets that will fit the GE head. MA performance makes some for relatively cheap and LQ9 coils aren’t expensive at all.
 

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Discussion Starter · #29 ·
Fabricated the patch-plates for the valve cover and welded them in:


Here it is mocked up:


And with the coils about where they'll be installed once my bracket is made:


I think I'm going to go ahead and weld the patch plates on the outside, too - and then grind/sand them down to hopefully make it look like one piece.
 

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Ahh, for some reason i had it pictured in my mind that they were positioned on top of the plug like oem, yeah that bracket should be sweet then.

Love your fabrication skills, wish i had some but mine is more machining than anything else. You might find weld, grind and bead blast will make it all look the same, or paint. It will never look perfect given one is cast and the other rolled plate, and who knows the casting grade of ali.
 

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Discussion Starter · #31 ·
Got the intake cam cover fully welded and fared down:


Scalped the top off the front "hump" of the exhaust cover, harvested the oil filler bung from the "hump" I cut off the intake cover, and prepared it for splicing:



Still need to drill/tap the oil filler so I can re-use the original baffle - the original bolt holes were lost in the harvesting process:
 

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Discussion Starter · #32 ·
Nailed down my scheme for crankcase ventilation. I'm going to join the two covers via a 5/8" line, then use a 1" line from the exhaust cover going to a Mann & Hummel 200L/min oil separator. I positioned the 5/8" vent points so they are NOT aligned with cam lobes - hopefully to minimize windage. The outlet in the intake cover is unbaffled, so I suspect there will be substantial oil entrained in the blowby gases exiting that cover. Those gases will enter the exhaust cover, into the unbaffled area. However, note the 1" outlet (to go to the catch can/oil separator) is in the baffled portion of the exhaust cover. I've included some pics of the fairly elaborate OEM Toyota baffling arrangement.





All that's left to do is powder coat these covers - I've got wrinkle black textured powder on the way.
 

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Progress looks good, and I think it will work well. It’s unique for sure, never seen a JZ with the oil fill port on the exhaust side. I have seen where fabricators fill in the “valley” on the GE covers to make them look more like GTE covers.

It must really sling the oil in there, judging by the amount of traps and baffles.
 

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Just picked up a GTE manifold from Dan from Rad on Facebook and got the adapter he makes to go with it. Anyways, I saw you notched the hood to clear the manifold, did you figure out what TB you are going to use and if there will be anymore clearance issues with it moving forward? My plan was to use the stock VVTI GTE upper and TB and was wondering if it will still clear with what notching you've already done or if you think there will be more or if it won't even fit.

Thanks for your help!

Tim.
 

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Discussion Starter · #36 ·
I'll be using a 68mm Bosch drive-by-wire throttle. I looked into a GTE-VVTi throttle, but they seemed to be fetching around $500 used and I was simply not going to give that much $ for an old used throttle.

I bought an adaptor from TAARKS in Australia, to mate the Bosch throttle to the GTE upper manifold, but there was zero chance in hell it was going to clear the hood with any amount of notching. It would have required a hole in the hood for it to stick up through.

I did not attempt a test fit of an OEM GTE-VVTi throttle, but I don't see how it would have been possible to fit under the hood. I could be wrong...

Instead, I'm fabricating an "adaptor elbow" that comes off the manifold and immediately begins a 45* downward bend towards the throttle. If you look through this thread, there is a link to another thread with some more details about the adaptor elbow.
 

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I'll be using a 68mm Bosch drive-by-wire throttle. I looked into a GTE-VVTi throttle, but they seemed to be fetching around $500 used and I was simply not going to give that much $ for an old used throttle.

I bought an adaptor from TAARKS in Australia, to mate the Bosch throttle to the GTE upper manifold, but there was zero chance in hell it was going to clear the hood with any amount of notching. It would have required a hole in the hood for it to stick up through.

I did not attempt a test fit of an OEM GTE-VVTi throttle, but I don't see how it would have been possible to fit under the hood. I could be wrong...

Instead, I'm fabricating an "adaptor elbow" that comes off the manifold and immediately begins a 45* downward bend towards the throttle. If you look through this thread, there is a link to another thread with some more details about the adaptor elbow.
Thanks for clearing that up. Well looks like I'll have a VVTI upper manifold and TB, and RADs GE to GTE adapter for sale next week!
 
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