I'm building this 66 225 slant 6 is it possible to use a harmonic balancer from a 76 225 engine

You can use any harmonic balancer for the slant six...the issues will be in the placement of the timing tab and the marks/indexing on the damper rin itself... If you are getting a 1976 damper, the easy swap would be to get a 1972-1976 Timing cover so the tab is in the correct spot.

My understanding is that the balancers are interchangeable between the forged crank engines. You might need to use the timing cover with the balancer from the same engine so that the timing marks will line up.

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-MattMan
LEANED & MEAN

Since the slant is neutral balanced you can interchange any of them... that being said, the cast crank balancers are a little heavier than the forged crank balancers due to the lighter weight of that crank and only the HD use slants got the 3 groove which would be counterproductive for use on a performance engine....

I currently run a 1976 forged crank damper and a 1979+ cast crank timing cover, and the timing marks match, FYI.

Well, that is good to know. I was wondering about the cast crank balancers.

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-MattMan
LEANED & MEAN

We pulled the damper off our engine last night....it looks original to the car and has 3 pulleys......one that we removed to pull the damper.

Overall looked like a 36 year old part. LOL

Saw cracking in the "rubber" seam on the front.....figured thats normal....but also figured that a new engine rebuild deserves a fresh damper.....

What is the general consensus....better to have the original rebuilt or will an aftermarket work ok?

I have an aftermarket on my 78 LA 318.....no issues....

Damper Doctor seems to want between $90 and $130 (I haven't gotten a quote back yet)...and new ones at Rock auto are the same price basically.

Things to watch for?

CLICK ME

I put one of these on my 76 D100 when my original damped failed earlier this year. It has worked great so far. Installation is a bit tricky since it is a solid three groove pulley and the crank snout bolt is too short to engage the threads on the crank for installation. I tried but screwed up the first few threads in the crank snout and had to actually buy a tap to clean up the crank threads.

I think I will just go with Damper Doctor.....I send him my old one, they rebuild it for $100 and send it back.....that way I know I wont be introducing any issues with an aftermarket part.

I have a DD damper on my motor that I bought off someone on this site. It has been fine, and probably subjected to more RPM than 99% of the Slants on the site.

One thing to watch for, we got one for a buddy's build and the outer ring was put on backwards. We never noticed until it was time to put the belt on. DD sent him a new one for free when he told them, didn't even want the other one back.

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