Er under bygging på SKI MOTORVERKSTED for 75 klassen. Corvetten er satt på vent et år til....
COSWORTH TWIN CAM
COSWORTH TWIN CAM
Er under bygging på SKI MOTORVERKSTED for 75 klassen. Corvetten er satt på vent et år til....
Tom Herskedal
It ain't over untill the fat lady sings !
It ain't over untill the fat lady sings !
Re: COSWORTH TWIN CAM
Cosworth har skapt mye racinghistorie, men ikke alle motorene har vært plagsomt suksessrike... GAA'n fikk bra resultater på tross av seg selv (smale rådelagertapper som gav høy rotasjonshastighet pga stor diameter, og høyt flatetrykk), og Vega'n var ikke akkurat noen kjempefest brukt i 2-liters racersportsvogner på syttitallet, Chevron og Lola...men er det noen som kan får herket til å gå fort MED holdbarhet er det vel Tom og Co. Så good luck guys, og velkommen med ennå en variant uten blå oval i grillen! Variety is the spice of life...4takt wrote:[
Er under bygging på SKI MOTORVERKSTED for 75 klassen. Corvetten er satt på vent et år til....
Doc
-
Dag-Henning Nielsen
- Champion!
- Posts: 1383
- Joined: 23 Mar 2004, 13:13
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- Contact:
GAA er 3,4 liter som i Caprien til Mats Cosworth Vegaen hadde betegnelsen EAA.
The Cosworth Story.
The Cosworth Company's view of the EAA engine, forerunner and design genesis for the Cosworth Vega
The following was written in 1988 as a portion
of the history of Cosworth Engineering as part
of the company's official information package.
(We have retained the original English(British) style)
The 1995cc EAA engine was based on the Chevrolet Vega block and was Cosworth's first non-Ford based stock block engine.
Early (Cosworth) engines had suffered reliability problems as tuners attempted to stretch what was, basically, a 1600cc to the full two litres, but it soon became evident that about 1840cc was the limit for the cast iron block. Later brazed cylinder liners, then an aluminium block, would overcome most of these problems although by now the massive resources of the BMW organisation were being mustered to dominate the category, thereby laying the ghost for all those FVA inspired defeats. Munich had learned well for their challenger bore more than a passing resemblance to its foe.
Other BD areas of operation have included the BDP for US midget racing with 230bhp from two litres by way of fuel injected methanol. This often overlooked aspect of American motor sport attracts loyal devotees to whom Cosworth have already sold over 80 engines, winning the West Coast championship in '86. Developed by the staff of the Company's Californian subsidiary, the BDP is continuing the theme that Mike Hall's design really is the motor sport engine for the masses having proved itself in a variety of arenas over the past 20 years. As the man says: "We built up a meccano set for the BDA with everything from about 11 00cc to two litres. People could come along and buy various bits. They still do."
That Mike referred to the EAA, the Chevrolet Vega, as 'the stumbling block' was perfect, for the phrase amply sums up the debacle.
"It was extremely light compared to the BDA with its pressure die-cast aluminium block from Reynolds, but was not up to the ratings we were putting through it. Designed to be a two litre racer, we could not make the cylinder block live. There was nothing we could do."
" It started as a race engine with Chevrolet, dry sump, the whole works, and it was Chevy who productionised it for the Vega car, They even had problems with the engine in road trim just as they did with the standard engine. The project died but they are now collectors' items!"
Thus the first road car to carry the Cosworth name did not enhance any reputations. It was not the engine which was at fault, only the block, but that tends to be somewhat critical and the whole episode fated before it began. Hundreds of blocks were being delivered, many failing a pressure test Cosworth devised for them and littering up the place while a solution was found. It never was.
Those which passed the test were released, the first version stirring in anger in Guy Edwards' Lola but failing to go the distance despite the attentions of Messrs. Duckworth and Scammell at Salzburgring.
It was the start of an ominous tale which resulted in the EAA never reaching sufficient status to go into Formula 2, Tommy Reid's hillclimb exploits heralding the greatest successes for this almost forgotten scheme. Forgotten that is until an example was recently found in one of Northampton's darkest corners. Perhaps it should be put on display with the epitaph that you cannot win all the time.
Alongside it there could be the JAA/JAB 750cc motorcycle twin cylinder developed for Norton Villiers in the mid seventies and described by Cosworth as a 'sad and sorry saga.' The least said about that the better.
Looking down the list of Cosworth engines, the memories are again stirred by another of Mike Hall's projects, the GAA. Based around a V6 'Essex' cylinder block, there were about 100 of the 3412cc, twin ohc/24 valvers made, belt driven. These became the basis of those mighty Cologne Capris that did so much to enhance the Group 2 saloon races of the early seventies when the likes of Jochen Mass and Klaus Ludwig fought the BMWs for supremacy. 440bhp at under 90OOrpm made the GAA a formidable beast and many were later installed in single seaters to take on the brutal Chevy V8s in Formula 5000, their relative compactness and lightness making up for any deficiency in outright power.
The EAA and Other CosworthEngines
Type Year Size Output Description
EAA 1972 1995cc 275 Bhp. Chevolet Vega, Formula 2 and Sports Cars, only successful in latter, used Vega alloy block, head similar to BD series, belt drive, productionized and built by Chevy in 122 BHP for the Cosworth Vega of the 70s
GAA 1973 3412cc 440 Bhp. Ford "Essex" V6 Race Engine, Capri/Granada block, 4 valve twincam belt drive heads, Group 2 touring and Formula 5000, 100 kits sold by Ford Motorsports
JAA 1974 750cc 65 Bhp. Norton-Villiers parallel twin Motorcycle Engine, DFV-like head layout, patron hit trouble and only 30 built
JBB 1975 750cc 95-110 Bhp. Racing Version of JAA, later injected
KAA 1978 2410cc 240-275 Bhp. Opel Ascona 400/Manta 400, used Opel Diesel block, 16 valve twincam for Group 4, injected for road at 140 Bhp, Webers for competition
OAA 1979 1600cc 170 Bhp. Formula SuperVee engine, based on single overhead cam Golf
WAA 1984 2297cc 187 Bhp. Mercedes-Benz, twincam conversion on M102 4 cylinder, originally for competition, then for road use in 190E 2.3-16
WAB 1988 2498cc 195 Bhp. Mercedes, increased displacement for '89 model year
WAC 1989 2490cc 330 Bhp. Mercedes, Group A short stroke '89 touring car racing
GBA 1986-87 1497cc 750-1000 Bhp. Formula 1, Turbo V6 Ford, Benetton get 1000 Bhp with fuel in '87
DBA 1987 3000cc 370 Bhp. GM-Pontiac, Cosworth 4 valve twincam head on production block, chain drive cams, kits
KBA 1987 1998cc 156 Bhp. Vauxhall-Opel, 16 valve twincam conversion of midrange engine, fitted to many models
HB 1989 3500cc 600+ Bhp. Formula 1, 75 degree V8 for Benetton '89 and customers
Source: http://www.race-cars.com/utility/coswrthr.htm
The Cosworth Story.
The Cosworth Company's view of the EAA engine, forerunner and design genesis for the Cosworth Vega
The following was written in 1988 as a portion
of the history of Cosworth Engineering as part
of the company's official information package.
(We have retained the original English(British) style)
The 1995cc EAA engine was based on the Chevrolet Vega block and was Cosworth's first non-Ford based stock block engine.
Early (Cosworth) engines had suffered reliability problems as tuners attempted to stretch what was, basically, a 1600cc to the full two litres, but it soon became evident that about 1840cc was the limit for the cast iron block. Later brazed cylinder liners, then an aluminium block, would overcome most of these problems although by now the massive resources of the BMW organisation were being mustered to dominate the category, thereby laying the ghost for all those FVA inspired defeats. Munich had learned well for their challenger bore more than a passing resemblance to its foe.
Other BD areas of operation have included the BDP for US midget racing with 230bhp from two litres by way of fuel injected methanol. This often overlooked aspect of American motor sport attracts loyal devotees to whom Cosworth have already sold over 80 engines, winning the West Coast championship in '86. Developed by the staff of the Company's Californian subsidiary, the BDP is continuing the theme that Mike Hall's design really is the motor sport engine for the masses having proved itself in a variety of arenas over the past 20 years. As the man says: "We built up a meccano set for the BDA with everything from about 11 00cc to two litres. People could come along and buy various bits. They still do."
That Mike referred to the EAA, the Chevrolet Vega, as 'the stumbling block' was perfect, for the phrase amply sums up the debacle.
"It was extremely light compared to the BDA with its pressure die-cast aluminium block from Reynolds, but was not up to the ratings we were putting through it. Designed to be a two litre racer, we could not make the cylinder block live. There was nothing we could do."
" It started as a race engine with Chevrolet, dry sump, the whole works, and it was Chevy who productionised it for the Vega car, They even had problems with the engine in road trim just as they did with the standard engine. The project died but they are now collectors' items!"
Thus the first road car to carry the Cosworth name did not enhance any reputations. It was not the engine which was at fault, only the block, but that tends to be somewhat critical and the whole episode fated before it began. Hundreds of blocks were being delivered, many failing a pressure test Cosworth devised for them and littering up the place while a solution was found. It never was.
Those which passed the test were released, the first version stirring in anger in Guy Edwards' Lola but failing to go the distance despite the attentions of Messrs. Duckworth and Scammell at Salzburgring.
It was the start of an ominous tale which resulted in the EAA never reaching sufficient status to go into Formula 2, Tommy Reid's hillclimb exploits heralding the greatest successes for this almost forgotten scheme. Forgotten that is until an example was recently found in one of Northampton's darkest corners. Perhaps it should be put on display with the epitaph that you cannot win all the time.
Alongside it there could be the JAA/JAB 750cc motorcycle twin cylinder developed for Norton Villiers in the mid seventies and described by Cosworth as a 'sad and sorry saga.' The least said about that the better.
Looking down the list of Cosworth engines, the memories are again stirred by another of Mike Hall's projects, the GAA. Based around a V6 'Essex' cylinder block, there were about 100 of the 3412cc, twin ohc/24 valvers made, belt driven. These became the basis of those mighty Cologne Capris that did so much to enhance the Group 2 saloon races of the early seventies when the likes of Jochen Mass and Klaus Ludwig fought the BMWs for supremacy. 440bhp at under 90OOrpm made the GAA a formidable beast and many were later installed in single seaters to take on the brutal Chevy V8s in Formula 5000, their relative compactness and lightness making up for any deficiency in outright power.
The EAA and Other CosworthEngines
Type Year Size Output Description
EAA 1972 1995cc 275 Bhp. Chevolet Vega, Formula 2 and Sports Cars, only successful in latter, used Vega alloy block, head similar to BD series, belt drive, productionized and built by Chevy in 122 BHP for the Cosworth Vega of the 70s
GAA 1973 3412cc 440 Bhp. Ford "Essex" V6 Race Engine, Capri/Granada block, 4 valve twincam belt drive heads, Group 2 touring and Formula 5000, 100 kits sold by Ford Motorsports
JAA 1974 750cc 65 Bhp. Norton-Villiers parallel twin Motorcycle Engine, DFV-like head layout, patron hit trouble and only 30 built
JBB 1975 750cc 95-110 Bhp. Racing Version of JAA, later injected
KAA 1978 2410cc 240-275 Bhp. Opel Ascona 400/Manta 400, used Opel Diesel block, 16 valve twincam for Group 4, injected for road at 140 Bhp, Webers for competition
OAA 1979 1600cc 170 Bhp. Formula SuperVee engine, based on single overhead cam Golf
WAA 1984 2297cc 187 Bhp. Mercedes-Benz, twincam conversion on M102 4 cylinder, originally for competition, then for road use in 190E 2.3-16
WAB 1988 2498cc 195 Bhp. Mercedes, increased displacement for '89 model year
WAC 1989 2490cc 330 Bhp. Mercedes, Group A short stroke '89 touring car racing
GBA 1986-87 1497cc 750-1000 Bhp. Formula 1, Turbo V6 Ford, Benetton get 1000 Bhp with fuel in '87
DBA 1987 3000cc 370 Bhp. GM-Pontiac, Cosworth 4 valve twincam head on production block, chain drive cams, kits
KBA 1987 1998cc 156 Bhp. Vauxhall-Opel, 16 valve twincam conversion of midrange engine, fitted to many models
HB 1989 3500cc 600+ Bhp. Formula 1, 75 degree V8 for Benetton '89 and customers
Source: http://www.race-cars.com/utility/coswrthr.htm
Tom Herskedal
It ain't over untill the fat lady sings !
It ain't over untill the fat lady sings !
Pssst....psssst.....PSSSSTT....:
http://www.ebay.com/itm/1973-1974-1975- ... 5f&vxp=mtr
En liten avsporing...leste et sted at en utøver i UK brukte et slikt topplokk på en Ford OHC motor i rally-cross...tror kanskje jeg hørte det av kommentatoren i en gammel film lagt ut på you-tube...
.
http://www.ebay.com/itm/1973-1974-1975- ... 5f&vxp=mtr
En liten avsporing...leste et sted at en utøver i UK brukte et slikt topplokk på en Ford OHC motor i rally-cross...tror kanskje jeg hørte det av kommentatoren i en gammel film lagt ut på you-tube...
.Jørn M. Hanssen