UK Based Performance VW Engine Specialist (est 1983)


The JMR Performance Guide CD costs £12 including postage.
You will be refunded the full amount against your first purchase of £100 or more.

I wrote this guide in order to explain what JMR is about and the philosophy behind the company. If you want a better understanding of the level of workmanship that must be put into a VW aircooled engine and/or transmission to achieve unrivalled reliability and performance, you need to read it. Whether you want a turn key engine or just some machine work to enable you to build your own engine, you’ll find valuable information you won’t have seen elsewhere. Having read the guide and seen the number of operations each and every JMR engine and transmission is subjected to, you’ll appreciate why John Maher Racing products have earned the reputation they have.

Topics covered in detail:

  CRANKCASE (case savers, machining, line boring)
    CRANKSHAFT (stock, stroker,8 – doweling, flywheels)
    CLUTCH (stock and heavy duty)
    CONRODS ( stock and heavy duty)
    PISTONS & CYLINDERS (selection, flycutting & dishing, ring gaps)
    CYLINDER HEADS (selection, unleaded fuel, porting, guides, valve job, machine work)
    VALVE SPRINGS (single or dual? retainers)
    ROCKER ARMS & PUSHRODS (stock, ratio, chromoly pushrods)
    CARBURETTORS (Weber, Dellorto, jetting)
    EXHAUSTS (selection, silencers, DIY kits)
    IGNITION (stock, alternatives, MSD, rev limiters)
    LUBRICATION & COOLING (oil pumps, deep sumps, filters, coolers, which oil?)
    COMPRESSION RATIO (how to calculate, deck height, cc’ing, semi hemi cut)
    ENGINE BUILD GUIDE (97 bhp & 125 bhp 1776cc, 175 bhp 2165cc, dyno graphs)
    TYPE 4 (overview)
    ENGINE MANAGEMENT SYSTEMS (the JMR system, features & benefits)
    NITROUS OXIDE (how does it work?)
    TURBOCHARGING THE VW (for street & strip)
    DYNO TESTING (how it works, testing, graphs, horsepower & torque explained)
    TRANSMISSIONS (matching ratios, strengthening, Berg 5,  gear charts)

In addition to the content listed above, there are several exclusive video clips, including drag race footage, world record VW engine change attempt, TV interview with John Maher and much more….