NEW Mallory Comp 9000 8754101H Vacuum/Centrifugal Advance Magnetic Breakerless Ignition (MBI) Distributor.
This is the Ultimate Street or Full Race distributor for Air Cooled Volkswagen engines!
It has largest distributor cap offered in the high performance industry, which allows you to run huge spark plug gaps for improved performance without worry about crossfiring inside the distributor.
Left Bosch, Middle Mallory Comp 9000, Right Mallory #271 small cap
It has a sealed ball bearing on the top of the distributor shaft which adds stability and durability and it is ready for full race 10,000 RPM conditions!
With an adjustable vacuum advance and adjustable centrifugal advance rate and adjustable maximum advance limit, it improves drivability on the street. It is a completely tuneable distributor, that will work with a stock 36 HP engine, or a full race fire breathing monster 2,400 CC engine.
The Adjustable Vacuum advance makes it perfect to use with aftermarket carburetors. It can add from 0 to 40 degrees of additional advance, at part throttle conditions, depending your setting.
If you don't wish to use the vacuum advance, you may insert a 3/32" Allen wrench through the nipple of the vacuum canister and turn the adjuster fully clockwise, which locks it solid. Or you can remove the canister and install vacuum canister eliminator plate. (Included)
It has an adjustable YH Centrifugal Advance system with Grey/Grey springs installed. It uses the 29014 spring kit.
I will install springs of any other color combination if you prefer.
The same color springs that work for your Mallory 2354101H, 2354109H, 2454101, 4554101H, 4654101H, & 4754101H will work in this distributor.
The maximum centrifugal advance may be adjusted from 0 to 28 degrees. It is presently set for 22 degrees maximum advance.
It has an access cover that allows you to adjust the spring perches without disassembling the distributor!
It has a CNC-machined 6061-T6 aluminum billet housing for added strength and reliability.
The shafts are centerless-ground and burnished to a surface finish of 4 microns.
It has a counterbalanced rotor and adapter shield interlock to prevent arcing and crossfiring.
Includes 3 wire connecting harness.
The milling marks have been polished out and all sharp edges have been deburred.
If Mallory actually sold this distributor it would be designated as an 8754101H Comp 9000 Magnetic Breakerless Ignition (MBI) Vacuum/Centrifugal Advance Distributor. Unfortunately Mallory never made the Comp 9000 series for 4-Cylinder engines. Fortunately, I figured out how to modify these distributors for Air Cooled VW engines.
This distributor is made from ALL NEW Mallory parts.
The Comp 9000 distributors have HUGE spacings inside that will allow you to use huge spark plug gaps for improved performance, without worry about crossfiring or arcing to the distributor body. The Comp 9000 4-Cylinder version can handle approximately 59,000V before crossfiring would occur, and I believe that it has the largest distributor cap spacings of ANY Air Cooled VW distributor.
By comparison, the small Mallory Distributor cap will arc-over, between the rotor and distributor body, at about 32,000V. The Bosch distributor cap can only handle about 28,000V before crossfiring or arc-over to the distributor body occurs.
People with 8-cylinder engines often do not want to use a vacuum advance distributor. This is because the vacuum advance changes the rotor phasing and reduces the spacing between terminals, which could cause a crossfire.
Fortunately with 4-cylinder engines, because of the additional 45 degrees of spacing between terminals, the vacuum advance does NOT introduce crossfiring problems.
There is NO performance penalty for using vacuum advance on a 4-cylinder engine!!!!
This distributor has been modified with a bracket, to prevent the distributor from retarding the ignition timing, in case the circlip wasn't installed properly in the vacuum advance pivot pin. It also prevents retarding if the pivot pin came loose from the advance plate. I have inspected the pivot pin and it is been properly staked to the advance plate. This has been a quality control issue with Mallory vacuum advance distributors.
If you have a Mallory vacuum advance distributor, I strongly suggest that you disassemble your distributor and make sure that this pivot pin has been staked in place!
This distributor is perfect to use with a High compression or Turbocharged engine. Remember, that spark plug gap arc-over voltage is directly related to the fuel mixture density. Anything that increases the fuel mixture density, such as higher compression ratio or supercharging, will also raise the arc-over voltage of the spark plug gap. Normally you have to reduce your spark plug gaps when you supercharge to prevent crossfiring or arc-over inside your distributor cap. With this distributor you can more than double the size of your spark plug gaps, as compared to a Bosch distributor.
Low compression engines will also benefit from wider spark plug gaps.
This distributor will fit most Type 1 and Type 2 engines with the newer mechanical fuel pumps. You DON'T need to use an electric pump! The distributor will physically fit any Type 1, Type 2, Type 3, or Type 4 engine case. However, I don't know if it will clear the fan shrouds or carb linkages of the Type 3 or Type 4 engines.
This distributor will work with Gene Berg dual carb fan shroud mount linkage and CB Performance dual carb Hex Bar Linkage. It will NOT fit with a stock 34PICT-3 carb, unless the carb arm is modified.
I don't know if it will fit with any two barrel center mount carbs. I also don't know if it will fit with bellcrank style carb linkage.
The top of the distributor sits 6" above the top of the distributor clamp. The distributor cap O.D. is 4-7/8" and measures 5-1/2" across the ears of the distributor cap. There is 2-3/4" between the distributor cap and the fan shroud.
The MBI module is less susceptible to thermal overload, than a Unilite module, because it has a much larger thermal clad circuit board to transfer heat, as compared to a Unilite module. While the MBI module can drive an ignition coil directly, anyone buying this distributor would be advised to use this distributor to trigger a high performance high energy ignition system such as a Jacobs, MSD, or Mallory. This distributor will work with any electronic ignition system that will trigger from breaker points.
Left: Mallory Magnetic Breakerless Ignition (MBI) Module, Right: Unilite Module
Many people don't realize it, but when using a multi-sparking ignition, the multi-sparking can continue even after the rotor tip has past the terminal and the spark is forced to jump a huge gap. Most centrifugal advance rotors have very narrow tips because the assumption has been made that there isn't any rotor phasing shift to contend with. Some vacuum advance rotors have tips that are wide enough to accommodate a multi-sparking advance. If you use a multi-sparking ignition that was designed for an 8-cylinder engine on a 4-cylinder engine, the multi-sparking which is usually limited to 22.5 degrees of crankshaft rotation, now continues for 45 degrees of crankshaft rotation. No rotor in production has a tip that is wide enough!
I solved this problem by cutting a new brass rotor tip with a longer trailing edge that can handle a full 45 crankshaft degrees of multi-sparking. The reduced spacing between the rotor tip and an adjacent terminal is still wide enough to prevent crossfiring.
The extra long trailing edge on my rotor tip can also accommodate the rotor phasing shift caused by electronic boost retard used with Turbochargers.
Left: My wider rotor tip, Middle: Mallory Vacuum Advance Rotor, Right: Mallory Centrifugal Advance Rotor
I'll be happy to answer any questions and send any additional photos that you require.
PayPal is preferred, although I will accept money orders. NO cash through the mail PLEASE! I can accept credit card payments through PayPal. You can check my feedback on e b a y under scottadriannovak.
Shipping will be actual cost from 55112.
NO handling or packing charges!
Scott Novak
sanovak@comcast.net
The Cal-look Lounge
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