McLaren M20#73

Howard Jones

Supporter
These do work and can be placed inside the tailpipes. I have considered making my own and putting them inside of a temporary bolt-on sound reduction "muffler" for quiet tracks using band clamps. I think they can be made for far less cost


 
Progress on the front engine plate. Recessed the cap screw engine mounting bolts. Alternator hole milled, bracket completed and alternator mounted.. Also milled the Oil pump hole and pump now in place. Have to collect the oil pump harmonic balancer mandrel from the engineer.
The Stainless Bros mufflers turned up in record time from the US. Purdy nice and shiney. SS welding superb..
Onto the blower. I’m making the procharger mounting plate which will eat up some hours, I’m sure.
Andrew.
 

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Hi Andy, looks great.

The front plate photo prompted a thought based on a near catastrophic failure I had. The grub screws on my oil pump pulley were tight but the pulley walked forward in competition to the extent that only 1/3 of the belt width was engaged on it. I only noticed by accident and I was probably only a whisker away from disaster. I made up a top-hat bush that slid over the pump driveshaft and bolted into the end, with the bush length set to make it impossible for the pulley to walk forward at all.

Cheers, Andrew

oil pump drive M20.JPG
 
Thanks for the heads up.
There is a bolt and washer that goes on the oil pump shaft end.
I can put a sleeve over the shaft to fill the gap to the pulley or cut the shaft which would be the neatest solution, but would have to tap a new hole into the hardened shaft which could be problematic.
As you know we have been in Aunty Jacinda's Delta lockdown once again, this useless Socialist Govt we have here in NZ couldn't organise a crap in a dunny.... Inoculations rollout near the worst in OECD countries.. which directly affects my engineers ability to machine my car parts :)
Luckily the restrictions are reducing (well outside of Auckland)
Managed to make a well needed run to the Fasteners supply shop for some bolts.. and order more parts.. keeping at it..
Andrew
 
Thanks Joyce, so am I :)
Just picked up the front Oil gear mandrel from the engineers. Had to get 3 extra holes drilled at the correct diameter and bevel. Fits nice.
Also got a Gates HTD 760-8M belt (Had to get a 2 tooth larger belt to fit the space better).
Can now plumb the scavenger pipes etc to the oil pump and tank.
 

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Was looking at some moroso scavenge screens, its on the list. But in the mean time I’ve plumbed the Scavenge lines up.
Installed a sleeve over the Oil pump shaft to arrest any pulley walk on the shaft. The pulley has 4 grub screws. 2 on the woodruft key and 2 directly on the shaft, so it looks pretty bullet proof.
 

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If so cool. I ripped the input shaft out of the TH400 I had in my previous track car and sent the guts of all the lifters into the sump on a mega over-rev Exactly the kind of shrapnel that would demo the oil pump!
 
Rocker mounted the IGN-1A coils on an ICT plate, running the spark plug leads between the header pipes in heat shields...... I just dont like the look or the enviable heat issues so will mount the coils on the rear bulkhead and run longer leads low in the chassis.
Nearing completion on the procharger mount. Waiting on a slightly shorter 10PK1335 belt and still have to mount the belt tensioner. The cold intake charge pipe also needs fabricating, will Vband clamp it on so their will be no pipes blowing off issues.
The front engine plate will then go on a further weight loss mill session, keeping at it.
Andrew
 

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Terry Oxandale

Skinny Man
I mounted the coils onto a fabricated bracket that bolted onto the block under the exhaust, and then ran the shorter plug wires up to the plugs. Was quite a bit cooler under, rather than over, on the heat put to the wires.
 
Hi Terry, still may block mount the coils but it's a bit tight to get access past/under hot pipes etc. Easier access from the underside of car but would require the engine bay floor cover to be removed.
I don’t know there would be any notable reduction in spark/engine performance running 400mm longer plug leads from the bulkhead.
 

Terry Oxandale

Skinny Man
My greatest concern with the longer leads was any interference into the fuel management system. No evidence that that would have been a problem, but some EFIs just seem to be more susceptible to that than others.

On a side note, I contemplated (and actually built) an under-engine floor, but never installed it. I guess my lack of confidence in a completely leak-free setup was an overriding fear that it wouldn't be easily detected with a floor under the drivetrain.
 
Completed the front engine plate milling.
Procharger mount all done and tensioner installed.
Still waiting on the shorter belt.
Got all the oil line parts AN-12 size. Moroso remote filter and an Earls 25 row oil cooler. Dug out an old Earls oil cooler that will work fine as the transaxle cooler.
Motion works LS steam kit also turned up.
 

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Hi guys, on the under tray, I have done that on my car for 2 reasons. 1) it protects the oil lines that have to run back under the oil pan. 2) it ties the bottom of the car together. The original cars have an oil pan that ties to the bell house and the front engine plate (which I have) but I also tie my under tray to the bell housing. Also makes for a very smooth and clean bottom of the car. That front engine plate is an art piece Andy.
 

Kevin Box

Supporter
Completed the front engine plate milling.
Procharger mount all done and tensioner installed.
Still waiting on the shorter belt.
Got all the oil line parts AN-12 size. Moroso remote filter and an Earls 25 row oil cooler. Dug out an old Earls oil cooler that will work fine as the transaxle cooler.
Motion works LS steam kit also turned up.
Nice work Andrew That must have taken a bit of time

cheers KB
 
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