8 rib belt upgrade complete - time for a new tune!
Hey Guys,
With the expert and exceedingly patient help from Blazen71 (forum member) an upgrade from 6 rib to 8 rib for my 03 MM was completed over the past summer.
I did all the wrenching.
Why? LOTS of 6 rib belt slip on the V7 SC and the need to spin the V7 SC faster for a given engine rpm. The 8 rib belt addressed the slip. A 10% OD innovators west crank pulley and a shrink of the SC pulley from 3.33" to 2.75" addressed the need to spin the V7 a bit faster.
Of course, every pulley had to be replaced.
Lots of spacing was required: idler pulleys, relocated idler pulley, SC pulley, alternator pulley, water pump pulley, tensioner and tensioner pulley, SC bracket and associated jigs. The new 8 rib clutched alternator pulley and the alternator itself needed mods, which Blazen71 figured out (in his sleep I think). I still don't understand how he did that, but it works great and reflects his high level of expertise and ability in this context.
A laser pulley alignment tool was used to ensure across the board pulley alignment. Water pump removal was necessary to align all.
The timing cover had to have raised marking (left side) ground down to ~ flush with the cover surface to remove 10% od crank pulley interference. I ground through the timing cover while doing this (despite warnings from Blazen71), which created a lot of extra work (removing valve covers, removing cover, welding/patching the hole, & putting it back together. I put a slight bend in the non OEM oil pan while tilting the engine from side to side to get the valve covers off; fortunately, not bad enough to cause oil pick up problems..whew).
I used a string around all the pulleys in order to get belt size info.
Fortunately, the elbow air pipe from the SC to the intake air pipe still fit, despite the SC bracket being spaced away from the block. It's a tight fit though.
On the 2nd post job test drive, I..uh.."goosed" the engine a bit going up a hill. The transmission downshifted and the boost popped more quickly than I expected , up to ~ 5psi and blew the air pipe off the throttle body, t-clamp and all. No tools, no phone, getting dark, country road. Crap. Waved down a direct TV repair guy. Being a paranoid in general (Blazen71 can attest) , I assumed the worst...as it made a loud BANG when it popped off; well, flat bed ride home. Got that tattoo now. :/
Time for a re-tune before really going after it!
-KK
'03 Silver Birch. Rebuilt 4.L 32V DOHC, V7-JT blower w/ADTR racing supercharger kit, Shift kit in transmission, stainless works long pipes and cat backs, Ridetech coil-overs front, shocks in back (ADTR kit). Rebuilt calipers, upgraded front rotors, OEM Mercury wheels, [boost, oil P, WB fuel/air, and fuel pressure] gauges. Build duration was Dec 2019 to Mar 2022. Upgraded to 8 rib belt to reduce slip, July-Nov '23. Car broke during tune with Marty Feb '24. Running again May '24. Still needs tune.
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