Honda British Touring Car drivers Gordon Shedden and Matt Neal do not believe they will be competitive at Silverstone this weekend.
Shedden and Neal are first and second in the drivers' table and have taken 12 wins from 24 races so far in 2012. Nearest rival Jason Plato is 32 points behind Shedden in his MG with six races left.
But that success has meant they have been kept on a lower turbo boost level than rivals, and Silverstone's simple National circuit tends to be horsepower-dominated.
Shedden, who leads Neal by three points, told AUTOSPORT: "Because Silverstone is only four corners it's not technically that much of a challenge so we could find ourselves not qualifying in the top 10.
"I think this will be the hardest weekend for us and I don't even think the wet would save us."
Neal, who clinched the title at the Northamptonshire circuit last season, added: "I don't think we'll even be in the race [at the front].
"In the wet it could be even worse because it's stop-start. At Rockingham there are some fast corners, but at Silverstone they're slow so you can't carry the speed."
Independents' championship leader Andrew Jordan, who also drives an NGTC Honda, is expecting a tough weekend against his rivals, many of whom race in older S2000 machinery.
His main title adversary, WSR's Rob Collard, drives an S2000 BMW, which has not been subjected to such extreme turbo restrictions this year.
"This weekend has got to be a damage limitation exercise for us," said Jordan, who confirmed the Eurotech squad had even considered running team-mate Jeff Smith's old S2000 Vauxhall Vectra because it is allowed more boost.
"I reckon the BMW will be quick and could win all the races.
"Copse is the only corner we'll be alright on - the others are slow so the weight [of the success ballast and the NGTC] and [lack of] power will hurt us on the exits."