Dennis Leech Group 2 Mustang
© Craig Olson, Steve Francis, Wolfgang Kohrn - 2007, updated November,27th 2015


The Mechanic speaks out:
Les Moyle (June 2011 report)
My Name is Les Moyle and I worked for Dennis Leech in the early 1970s. I worked on the Mustang when it was in its 429 guise. Had the pleasure of a ride in it at Silverstone, it was up the runway after some late night repairs. Never felt acceleration like it before or since, it was unbelievable.

I worked on the installation of the Boss 429 motor, under Dennis's guidance. It was much wider than the 302 or the 351 so the suspension turrets had to be cut back so the rocker covers would fit. I then fabricated a set of stainless steel headers that were taken into 4 into 1 collectors on both sides. The 4" exhaust exiting out of each side under the doors. Originally running on a four barrel Holley Carburettor and standard 429 heads, it was modified with a set of Alloy Weslake 4 valve per cylinder heads and a Formula 1 style slide throttles with fuel injection. This was totally manufactured by Dennis with the help of an engineering works that were in the unit next to Dennis's garage.
Your website brought back lots of memories for me. I am nearly 62 and Dennis is 68. I was in my early twenties when I worked for Dennis.
Best regards
Les Moyle/June 2011

Previous Owner Eric Walker (UK)
Yes I remember another car I once owned - the Dennis Leech Boss Mustang built as a 302 in 1970 in a light metallic colour, raced by Jacky Ickx at Spa, run as a 351 in 1971 in white, black and red livery and a full blown Boss 429 in bright metallic tourquoise blue in '72/73 this car has been back in the USA since the mid 90's under restoration - I'm surprised no-one is looking into the history of this one as it was really spectacular when running the 429.

By the time I got it, it was white with blue stripe and had last been driven by Roy Pierpoint in an ASCAR club race.
Roy Yates then bought it and swaped all the suspension onto his later Fastback. I helped locate it for the guy in the States who had to import both cars and is still as far as I know rebuilding it.
I sold it as a rolling chassis to a guy who planned to drop a Chevy in it but luckily got no further!
Had to sell the ex- Leech Boss 429, Ex Alan Mann Falcon Sprint, the remains of Martin Birranes '67 Notchback 427 racer -which was broken up for parts, the ex Piers Courage 66 Shelby GT350 (by then a full race quad weber hillclimb car but dismantled when I sold it) and a 68 GT500.
Eric Walker/April2004

Previous Owner Keith Hardy

I never took pictures, the car was a mess. I only got as far as measuring the suspension points to see if it was straight and it was a mile out. It had a lot of battle damage and needed a lot of work to put right. I remember picking it up on a trailer in the Midlands and several miles later, the trailer jack knifed and broke the hitch, so it spent it's first night of my ownership in a night-club car park under the watchful eye of a handful of large security men.

I sold it after a year - no work carried out. I got divorced and moved to the US for a few years.  It was not a Boss 429 Mustang, it was a standard 302 Mustang that arrived here with a bunch of HD parts in the trunk. The car was never supported or recognised by Ford as the "real deal" and although very quick in a straight line with Dennis at the wheel, it was overall a complete disaster with probably never a finish to it's name. It provided probably the most spectacular engine failures ever seen in a racing series.  I'm curious to see it reappearing.

My interest was in Mustangs, I used to own a couple of Shelby's and a Tiger in the '80's, but I also raced Al Unser Snr's 1978 IROC Camaro in the UK for a while seen here at Goodwood on an AMOC Sprint together with my Trans-Am.

Keith Hardy (Feb. 2007)
(Picture of Camaro #18 built by Roger Penske available)

Back in the early 1970s in the RAC saloon car championship Leech was racing this Gp2 Mustang along side several pedigree T/A and A/S race cars from the USA, such as an ex-Bud Moore T/A 69 Mustang, ex-Kar Kraft 70 Boss 302 mule (from the Boss 302 chassis modification book) and an ex-Penske T/A 69 Camaro. Most of these race cars have found there way back to the USA, but not all of them. Steve Francis

Dennis Leech Group 2 Mustang
Dennis Leech racing at Silverstone 1971 
Picture courtesy Trevor Legate 

Dennis Leech chased by Martin Birrane 1971
Picture courtesy Eric Walker 

Leech was a privateer racer known for racing wild American Ford V8 powered saloon cars and his plaid flannel shirts. 
The Mustang arrived at Leech's Exeter shop in early 1970 as a Boss 302. While being built to Group 2 Saloon Car spec Leech sent off a race entry for the March 1970 Gaurds Trophy at Brand Hatch, but the car was not ready in time. 

Two months later they hauled over to Spa-Francorchamps in the Ardennes hills of Belgium for a support race to the 1000KM. This time Leech put Jackie Ickx in the drivers seat and while leading early on a head gasket let go putting the Boss Mustang out of the race.

For 1971 Leech acquired sponsorship from Castrol and there was an engine change from the 302 to a 351 on Webers. Leech summed up the 1971 season as a "waste of time". 

For 1972 the Mustang had yet another engine swap. This time it was a Boss 429 supplied by Holman & Moody which Leech then designed and built his own fuel injection system for. In a addition to the dry sump 7 litre engine the Mustang ran a triple disc clutch setup, a NASCAR spec 4spd trans, Detroit locker, Watts link, Konis, spherical rod ends wherever possible, power assisted Girling disc brakes, 22 gal fuel cell and formula 1 type 15"x 15.5" rear wheels and 15"x 12" fronts on Goodyear tires.

When Eric Walker owned it.


The following pics are from 1992 when the car was sitting at Roy Yates Derbyshire workshop

Pictures courtesy Steve Francis

The last and current owner is Craig Olson. 

The car is still on sale (2014) and we will forward any serious interested inquiry.

Dyno sheet of the engine will follow soon.

As of May 2015 the car got sold handed over with all the documentation to Bill Shepherd. He will return it to the Dennis Leech livery, when it was raced in the UK.
Weare looking forward to see it in its former glory in the 2016 season.

See this story (2012) from Steve Holmes on the Leech car at

Below is not the former Leech car in its current dress, but another of Craig Olsons cars, he currently it appeared in 2008 


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