Roller chain for roller cams....

[powerdoctor]

I'm going to show you how it was done.

I am including pictures...

I dug out an old roller chain cam sproket and took apart an old 3.1 to show you guys.

Pic 1, the roller chain gear.
Pic 2, the roller cam, 00' 3.1
Pic 3, roller sproket on cam, with hole reamed out.
Pic 4, what you need to "take off" ( the thrust surface on the roller chain sprocket ) for the roller chain sproket to work.

It also requires different bolts for the thrust plate to clear the sproket, or grind down the stock ones.

You can weld the old holes in the sproket shut if you want.

This is all to retain the stock roller cam thrust plate or walk eliminator, and add a roller chain as well.

While I have NOT tried it under a modular cover, it clears the RWD cover just fine.

[powerdoctor]

here's another shot of a 3.1 roller still assembled with the roller sprocket sitting next to it.
It looks to me that it would clear the modluar cover after the surface was taken off...

[ForcedFirebird]

I looked at this, but the fact still remains that the cam is held in place by a single center bolt and a tiny little pin. As soon as you detonate, I don't care how strong the gear set is, there has been many reports of pin failure. Normally on an iron head motor, this is a non-factor because the valves won't make contact with the pistons when out of timing, but might with the flat-tops, and definately will with AL heads.

My idea is to use a solid roller cam with the Gen1 660 style sprocket with three bolts, in a Gen1 block and modified roller lifter ratiners. It will still need some sort of retainer, but I'll get to that later.

[powerdoctor]

Its that way on the aluminum heads engine as well.
I do agree with you on the pin being a weak link.
I thought about drilling the roller cam for the 3 bolts in the old stlye cam sproket.
I have concerns about this though.
What cam are you talking about?

[ForcedFirebird]

Its that way on the aluminum heads engine as well.
I do agree with you on the pin being a weak link.
I thought about drilling the roller cam for the 3 bolts in the old stlye cam sproket.
I have concerns about this though.
What cam are you talking about?

The iron heads with the stock dished pistons are NOT interference.

I'm going to be using a Gen1 (non-roller) block, converting it to use the Gen3 stock roller lifters and a custom Gen1 roller bumpstick.

[powerdoctor]

no, what I meant was the cam sproket is still held on in the newer engines the same way, one bolt.
You are doing a roller cam conversion on your 3.4?
As far as I knew the 3.4 rwd were flat tappet.

You could probably machine the lifter bosses and get the roller lifters to work.
What would you use for retainers?

I wonder if the sbc slotted after market rollers would work.

I should look into that.

[ForcedFirebird]

no, what I meant was the cam sproket is still held on in the newer engines the same way, one bolt.
You are doing a roller cam conversion on your 3.4?
As far as I knew the 3.4 rwd were flat tappet.

You could probably machine the lifter bosses and get the roller lifters to work.
What would you use for retainers?

I wonder if the sbc slotted after market rollers would work.

I should look into that.

The Gen1 blocks have a 3 bolt pattern.

The bosses don't need machining, the lifters on the Gen3's are taller and protrude from the block enough to have the plastic retainers on there. I own a CNC/fabrication shop and have studied/measured the Gen 1 (2.8-3.4) engins thouroughly. I also bought a few 3500's and sold off the parts just to really check them out and see if I can get one into my car. In fact I only have the rods, pistons, lifters and idler pulley left, lol - everything else got sold off. One of the blocks is going in a Midget car that got 340hp out of a 3.4, full roller coversion, individual TB's, forged crank etc. It's replacing the 320hp iron duke 2.5 that he's racing now

[CNCguy]

After cutting the back of the gear flat, what did you use to space it back out to clear the retainer? Did you also cut the lower gear to move it back to maintain chain alignment? If so, did you make a spacer to move the dampener back out to maintain belt alignment?

You make it sound so easy but there is more to it than what you have described. It would be more helpful to others if you waited until it was a proven method, then post each step of the modification with pictures.

I hate to see people rush out and waste money without knowing what's involved, if it will work or destroying parts when the pin shears off.

Perhaps your name should be PowerIntern since you are just learning about these engines.

[powerdoctor]

Is that power made with iron heads or aluminum?

Is it N/A ?

[ForcedFirebird]

Is that power made with iron heads or aluminum?

Is it N/A ?

The 60* was using 3400 heads (modified of course), but he is now going with 3500 heads after I showed him the differences.

The iron duke is uing a single V8 AL head, again with Hillborn-type individual TB's.

[powerdoctor]

Nothing ventured nothing gained, right?

I am sorry and will state that it is experimental and has not been proven.

If some ones wishes to try this as I have, this is how I did it.

And no spacing of the crank or balancer was required.

Once the back of the sproket was taken down and the holes opened up, it lined up fine.

[ForcedFirebird]

Using the RWD cover, did you use the RWD dampener and pulley, then?

The RWD cover also need the extra water passage blocked.

[powerdoctor]

Yes it does need the passage filled.
What I did was thread the cover for a pipe plug and screw one in.
Screw heli arc for something so minute.

Yes I used the balancer from the 3.4 rwd.

[CNCguy]

If you didn't use a spacer or turn a step on the rear of the sprocket, what is keeping the retainer from being compressed between the cam and the sprocket? If you turned a step on the back side, then the sprockets are out of alignment. Not trying to beat a dead horse but I'd hate to see your fresh engine get trashed.

[powerdoctor]

take this away cnc guy, you got it covered.

See you on your thread.