You boys are overlooking the big thing with production based 4 cylinder junk and thats intake runner volume is nearly always the choke point or limiting factor. Runners are made small so there's going to be good port velocity on the stock set up. Good runner velocity means good low pressure thru the carb and that means it will pick up fuel nicely..
Three motors that I know the best guys for rally motors is Saab, Volvo and VW, and in all three if you retain OEM intake manifold---as the old Group A rules mandated, you won't see more than about 175 bhp no matter what you do...The runners are built in restrictors just like the gawddam junk on the turbo inlets..
With regard rally and rally motor power its easier to name the few motors that have runners intended to pass air enough for reasonable power, and all were built as "homologation specials"
Nissan Sentra SER 2.0 16v (86 x 86)
Opel XE 2.0 16v (86 x 86)
Ford RS2000 16v (also 86 x 86)
Various Peugeot and Renault 2.0 16vs XU9 (1900) and XU10 at 2.0 (86 x 86)
Some Citroen motors (a lot in incest in French engines).
Since Grant is always going on about he's way high--in altitude I think he means---he says he needs 300 bhp so that he has 100 at high altitude..or something..
So knowing the configuration of the disgusting spaghetti sized candelabra that passes for an intake manifold I'd be worried about anything other than 4 individual runners and throttles..in short ITB or DCOE carbs--at least 48s.
But as always what the fuck do I know...its not like I've built rally motors for 25 years...
Oh wait, I do. nevermind.
John Vanlandingham
Sleezattle, WA, USA
Vive le Prole-le-ralliat
www.rallyrace.net/jvab
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