Crank pulley, 6 cylinder gurus Options

[Montreal914]

I would like to get rid of this double pulley on the crank of my 86 3.2 engine and replace it with a single pulley like the early engines.

Which year or engine single pulley would be compatible (same diameter) as a replacement? Would it have the same timing marks?

Or, have people drilled the spot welds to get rid of the A/C pulley? (IMG:style_emoticons/default/confused24.gif)

[Spoke]

I'm changing the V-belt and dual pulley like yours on my '86 930 to a Clewett serpentine flat belt like modern vehicles. Thus getting rid of the ridiculous belt adjustment via shims.

[Montreal914]

Yes, this looks very good but I don't know if it fits with my engine mount (Maddogs dual mount).

When looking at the Clewett website, they describe this kit as "Undedrive" for 74-89. I guess this means my pulley (86) is smaller than 73 and earlier? Does this mean that a stock single 74-89 pulley would work? (IMG:style_emoticons/default/idea.gif) I assume not all 911 of those years came with A/C?

[sixnotfour]

74-89 crank pulley will work TDC and 120 deg. marks correct..
I have cut the ac pulley off in a lathe, Drilling spot welds works too.

some 3.2 double pulleys have a balance weight spot welded on .. I think cutting off the AC negates the need for the balance weight....are least close enough for street.

[Spoke]

Yes, this looks very good but I don't know if it fits with my engine mount (Maddogs dual mount).

When looking at the Clewett website, they describe this kit as "Undedrive" for 74-89. I guess this means my pulley (86) is smaller than 73 and earlier? Does this mean that a stock single 74-89 pulley would work? (IMG:style_emoticons/default/idea.gif) I assume not all 911 of those years came with A/C?

They have a version with the stock ratio.

3.2-3.3 Serpentine fan belt conversion 1984-89 - Stock Ratio

I bought the version with the crank trigger as I'm getting rid of the distributor and going coil on plug.

[mepstein]

Yes, people do remove the dual pulley on a 3.2, either with a single pulley or modifying the stock one. A lathe makes it easy. One advantage is you don't need to use the expensive and harder to find Carrera engine mount.
The Clewett pulley system does specify a Carrera mount so I'm guessing it's pully system is slightly wider than a single oem pulley.

I don't know if the Clewett pulley fits in with the Maddog mount. It probably does but I haven't checked. Removing the a/c portion of the Carrera pulley or housing the correct earlier pulley is really the best and most cost effective way to insure it will fit perfectly for your six conversion.

[Cairo94507]

We did the Clewett serpentine belt pulley system on my 3.6 and I love it. My 3.6 is installed with the factory 914-6 engine mount that we modified slightly. The biggest crime is that once the engine is in place, you don't get to see the Clewett belt system. (IMG:style_emoticons/default/beerchug.gif)

[mepstein]

We did the Clewett serpentine belt pulley system on my 3.6 and I love it. My 3.6 is installed with the factory 914-6 engine mount that we modified slightly. The biggest crime is that once the engine is in place, you don't get to see the Clewett belt system. (IMG:style_emoticons/default/beerchug.gif)

I'm using it on my 67 build with a 3.2, partly because, like Spoke, I wanted a trigger wheel for electronic ignition, partly because I'm using an uprated alternator for a/c. It also substitutes the heavy stock pulley for a much lighter one.

[Montreal914]

All, thank you for the great inputs! (IMG:style_emoticons/default/smilie_pokal.gif)

Doesn't look like my pulley has any balance weight to it so I could get it turned and removed.

That being said, I really like the Clewett Eng setup, and I am definitely curious about all the nice upgrades it can provide!

@Spoke ; When using the Clewett as a crank trigger, could this work with the stock Motronic setup or it would be for aftermarket EFI only?

@mepstein ; There could potentially be an electric A/C in the picture on my car too which would require an upgraded alternator as previously discussed. What makes the Clewett setup a better fit for the updated alternator, the non-slip timing belt drive?

I will contact Clewett to get more information. They are local to me, it would be great if I could bring my Maddogs mount to see if they could be compatible.

[mepstein]

All, thank you for the great inputs! (IMG:style_emoticons/default/smilie_pokal.gif)

Doesn't look like my pulley has any balance weight to it so I could get it turned and removed.

That being said, I really like the Clewett Eng setup, and I am definitely curious about all the nice upgrades it can provide!

@Spoke ; When using the Clewett as a crank trigger, could this work with the stock Motronic setup or it would be for aftermarket EFI only?

@mepstein ; There could potentially be an electric A/C in the picture on my car too which would require an upgraded alternator as previously discussed. What makes the Clewett setup a better fit for the updated alternator, the non-slip timing belt drive?

I will contact Clewett to get more information. They are local to me, it would be great if I could bring my Maddogs mount to see if they could be compatible.

The stock motronic has it's own sensor that reads off the flywheel. Spoke (and myself) are using the Clewett trigger wheel and an aftermarket electronic ignition that will replace the stock distributer and use coil on plug. Neither of us are using aftermarket EFI (at lest at the moment) For myself, the aftermarket ignition makes twin plug easy. For spoke, it makes it reliable and easy to custom tune. I'll still be using the stock Motronic Ecu for fuel injection on my 3.2 engine. Spoke is using stock turbo cis on his 3.3 engine.

We have installed many electric a/c units with the stock pulley system. Jonny at CR says the Clewett system works best for the highest amperage units. Admittedly, I know one top engine builder who doesn't like the Clewett system but we all have to do what we think is right for ourselves.

[mepstein]

Just a quick note about the aftermarket ignition. It does require a custom harness and tuning. It’s not a plug and play like say a 123 distributor.

[Montreal914]

Just a quick note about the aftermarket ignition. It does require a custom harness and tuning. It’s not a plug and play like say a 123 distributor.

Mark, noted. Thanks! (IMG:style_emoticons/default/beerchug.gif) I will stay stock.

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Looks like @ClayPerrine used a Clewett setup as a foundation to an A/C integration and was using a Maddogs (or similar design) dual support like I plan on using. Here's his post I found on the Pelican forum.

Clay, is the first pulley above the crank one the regular Clewitt tensioner? Do you remember having fitment issues with the engine mount? I know it's already been 20+years, but if you have any recollections, I would appreciate. (IMG:style_emoticons/default/beerchug.gif)

https://forums.pelicanparts.com/porsche-911...e-belt-kit.html

[ClayPerrine]

Just a quick note about the aftermarket ignition. It does require a custom harness and tuning. It’s not a plug and play like say a 123 distributor.

Mark, noted. Thanks! (IMG:style_emoticons/default/beerchug.gif) I will stay stock.

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Looks like @ClayPerrine used a Clewett setup as a foundation to an A/C integration and was using a Maddogs (or similar design) dual support like I plan on using. Here's his post I found on the Pelican forum.

Clay, is the first pulley above the crank one the regular Clewitt tensioner? Do you remember having fitment issues with the engine mount? I know it's already been 20+years, but if you have any recollections, I would appreciate. (IMG:style_emoticons/default/beerchug.gif)

https://forums.pelicanparts.com/porsche-911...e-belt-kit.html

I built that using the Clewett pulleys on the crank and the fan. It worked fine, and the belt was easy to change. But the extra stress on the timing box cracked it and it started to leak oil. The tensioner I used was the timing belt tensioner for a Nissan 300ZX (engine number VG30). It is a simple eccentric idler. It was a very heavy setup, all made from plate steel.

Looking back at it, I don't see how to change it. The engine actually expands when it warms up, so you can't extend the front support to the engine mount. These days I would say get a high output alternator and run an electric AC compressor.