1200 getting modded to accept ignition drive from cam gear

[dan filipi]

Sub chapter of 1200 install....

I was going to install the C5 on the rear of the 84 1200 engine but not being accessible for reprogramming won't work for me.
Here's my plan to make the C5 easily accessible.


Using an 1100 ignition housing which I'll mount to the belt cover.....

Original cam bolt removed and replaced with a longer bolt, jamb nut to secure gear......... Cut off hex head and thread it.......

End result....A spinning rod to attach C5 pickup wheel to.

 

[brianinpa]

Well that sure is outside of the box! :clapping:

 

[joedrum]

brianinpa » Tue Mar 18, 2014 12:29 pm[/url]":3jgqfrl7]
Well that sure is outside of the box! :clapping:

box what box opcorn:

 

[Steve83]

Looks good! It should work mechanically - hopefully the electronics can be programmed to double the firing rate, since it will be turning half as fast.

 

[AApple]

But....but.....the cams spin at a different speed than the crank! Cams turn at 1/2 crank speed....this won't work, will it? :headscratch: :nea:

IF you use the set-up for the 1000, which runs off of the cam, it might, but....it's gunna be spinnin backerds.....no?

 

[KYWinger]

Necessity is the mother of Invention - you've proved that once again! Assuming you can get Paul to make a wheel that works.....

 

[dan filipi]

C5 doesn't care about rotation direction and It can be programmed for the different spin speed and the wheels are all the same.

I'm buying the programming kit today.

Joe doesnt want me to do this saying the crank is more accurate. I don't agree.

 

[KYWinger]

Will the 1200 head take a rear drive like the 1000 or 1100 w/371 cams?

 

[dan filipi]

KYWinger » Tue Mar 18, 2014 9:39 am[/url]":1kynd79a]
Will the 1200 head take a rear drive like the 1000 or 1100 w/371 cams?

Not without making a different housing or possibly adapter and tapping the cam end for a stud but I am looking closer at that option yet.

 

[joedrum]

Ive done it its not and easy mod ... and fruitless in my case cause the 371 cams mad the valves hit the piston ....once that happen I could care less about the 1200 heads ..personally don't like um ... so with head change to 1100 heads there was no need for the adapter plates I made for the 1000 ignition or the fuel pump adaptor plate I made for 1000 mechanical fuel pump.... anything possible for sure

 

[AApple]

dan filipi » Tue Mar 18, 2014 12:36 pm[/url]":1bhv4tl3]
C5 doesn't care about rotation direction and It can be programmed for the different spin speed and the wheels are all the same.

Thass kewl! Dint know that, but I kinda suspected it would work in either direction, just weren't sure about the 1/2 speed deal. The C5 set-up just keeps gettin better and better! :good: :clapping:

 

[Steve83]

Another option for the 1200 head rear mount would be to use a fuel injection right cam, which has a stub on it to drive the cam sensors. I have a set if you want to try...

 

[ekvh]

I agree with Joe about the crank being more accurate from a timing point as the crank has no flex of the belts to influence it, but with the multiple spark ability of the C5 it's probably moot. I think it may factor in on the cams at low rpm only. If you watch them idling, there is a little bounce to the belts. It might be one of the factors in the lopey idle of the flat fours.

 

[mcgovern61]

ekvh » Tue Mar 18, 2014 2:21 pm[/url]":3mg7mut2]
I agree with Joe about the crank being more accurate from a timing point as the crank has no flex of the belts to influence it, but with the multiple spark ability of the C5 it's probably moot. I think it may factor in on the cams at low rpm only. If you watch them idling, there is a little bounce to the belts. It might be one of the factors in the lopey idle of the flat fours.

The timing belts are gear belts. What I like about them is that they have very little stretch because of their construction, yet are flexible enough to roll over pulley's for years without deformation! Unfortunately, that same construction is why, when they fail, there is usually no warning.

As far as bouncing at idle, is it on the tension side of the belt (leading into the pulley) that you notice the bouncing, or the return side?

Another question from the peanut gallery.......I know the C5 for the 1000 installs on the left head (cam shaft), how would it be any different if installed on the front of the same cam shaft (like the 1200, such as this)?

 

[Steve83]

I'm guessing the cam moves less than 1 degree with even serious belt slop. If the belt is loose enough to cause a noticeable timing change, it's probably loose enough to jump a tooth. Hopefully none of us let that happen!

 

[slabghost]

That should work just fine. Although you may need to reduce the bolt size a bit for the c5. A felt washer on the shaft at the belt cover hole should keep any dust out. What is the plan for flattening the belt cover surface to mount the housing securely? bolt flat and epoxy fill? :builder:

 

[skiri251]

Dan, so do you feel the need for tweaking C5?
It's certainly nice if it fails (hope not). So much easier to tend to.

 

[dan filipi]

skiri251 » Tue Mar 18, 2014 1:22 pm[/url]":23ks7r5l]
Dan, so do you feel the need for tweaking C5?
It's certainly nice if it fails (hope not). So much easier to tend to.

No I feel the curves of the c5 as programmed are good for the 1100 but I'm uncertain about these for the 1200 since it full advances to 45 degrees, 1100 38.5.
Also running a single carb I feel it can use more advance.

 

[charles franz]

Very interesting mod,I am very interested! Charlie in NC

 

[dan filipi]

The 1984 belt covers arrived.....

Threaded drive stud through cover, marked for cutout of 1100 ignition housing

Jig saw then dremel grind to clean fit

Test fit on the engine for centering

Covers are not flat which leaves a gap.
It's getting a gasket and RTV to seal it.

Right side fit

Left side fit

Needed some modification of the housing to make C5 board sit flat how I needed it.

Done machined flat

Test fit and screw holes drilled

C5 board screwed into housing, housing mounted to belt cover.
I need to tap another screw to the belt cover in the right bottom

Working on the drive stud spacer for the encoder wheel........