Harmonic Balancer Adapter

[Warrenm]

This is the 1st project that I've posted up here, so here it goes.
As the title says, it's an adapter to fit a balancer to a 6 cylinder 202 Holden engine. As it is an Australian GM engine & the balancer is made in the USA, they don't make an adapter to fit this application.
I purchased a piece of steel, 4"long , 4"diameter, which ended up being 4140(but I was only charged for "Bright" steel  .
This is what it looked like at the start. 

[enginenut]

what balancer are you trying to  adapt??? why not use an off the shelf one ??? not trying to be a wanker just curious that's all

[Stilldrillin]

what balancer are you trying to  adapt??? why not use an off the shelf one ??? not trying to be a wanker just curious that's all

As he says..... "they don't make an adapter to fit this application."

David D

[Warrenm]

what balancer are you trying to  adapt??? why not use an off the shelf one ??? not trying to be a wanker just curious that's all

I'm fitting an ATI Super Damper. This is an inline 6 that has all the usual balance issues you get when you start to spin them over 7000rpm. The only balancers that are available to suit this engine are the std type, that are not heavy enough, or one made by Romac which is heavier, but still not heavy enough.
Now for an update. The 4140 is an Australian standard, the British standard is BS970-1955 EN19A.
A plan of what the finished article should look like & some progress on the lathe.

[enginenut]

No David they don't make an 'adapter' for this application but they do make several balancers which is why i asked. I have built several of these engines and have always found the ones availible in Australia to be sufficent. Warrenm is it a red, blue or black ?? Red i can understand adapting a larger balancer but I usually retro fit a blue crank due to them having better counterweights. Also if your going the supercharged route fit a second key to the crank

 

[Warrenm]

No David they don't make an 'adapter' for this application but they do make several balancers which is why i asked. I have built several of these engines and have always found the ones availible in Australia to be sufficent. Warrenm is it a red, blue or black ?? Red i can understand adapting a larger balancer but I usually retro fit a blue crank due to them having better counterweights. Also if your going the supercharged route fit a second key to the crank

 

Red motor blue crank. No it's not supercharged, it's has 3x 2" SU's.

[Pete49]

Also a good way to get onto the lathe. Maybe a reason is he wants to do it Some people like me go for the challenge rather than the wallet though in my case it would be for the learning involved
Pete

[enginenut]

sounds like nice little Torrie or EK EH project they go well with a hot red in them

[Warrenm]

The engine is in a 1972 LJ Torana. It runs 12.62 on the 1/4 mile.
I've now parted the adapter of & turned it around in the chuck so that I can finish the other side.
Just need to broach the key way & drill & tap some holes to bolt the balancer to.

[Warrenm]

Bit of an update to my small project.
Using a transfer punch, I marked the mounting holes. I didn't take any pics in the drill, then tapped the threads, 3x 3/8" UNC & 6X 5/16" UNC.



Now I need to visit my good mate & use his broach to cut the 3/16" key way.
This the std balancer (2.5lbs)& the Super Damper(8.5lbs) for comparison.

I then machined a .060" shim from brass, I'm not sure what this does, but was told some years ago when fitting a larger balancer to these cranks to use a .050"-.060" brass shim, as the cranks have a habit of breaking with the extra weight & this helped to stop it. Maybe some one may have an opinion on this subject.

[SPiN Racing]

Nicely done.

I for one wanna see the beastie that rides inside 

[Warrenm]

Nicely done.

I for one wanna see the beastie that rides inside 

Here are some pics & footage from a few months ago.

[enginenut]

Mmmmmmmmm Holdeny Holdeny goodness! Looks like it hooks up well, what trans and diff ratio???

[Warrenm]

I use a Saginaw 4 speed & 4.88:1 diff gears.

[SPiN Racing]

Oh that baby is sweet!

I used to have a 72 RX3, and the front of that Holden reminds me of a early Mazda 808 I had picked up from one of the salavage yards. It had a similar frontend, headlights and grill wise.

Cool Car

[jatt]

I was pretty happy with the 5000 rpm I was getting out of my 179 out on the speedway track, bottom end knock and all. From   Throwing a rod out thru the side was definetely the biggest concern.

Over 7000 sounds pretty good for the old push rod unit.