40 IDF vs 44IDF on 8VTC

Tech chat w/ Marc Matzer
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Marc
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Joined: Tue Mar 21, 2006 1:15 pm

40 IDF vs 44IDF on 8VTC

Post by Marc » Tue Jul 31, 2012 8:47 am

Choosing twin carbs for your 8 valve TC on 1800 cc or 2000cc engines it is recommended that you have a big valve head before jumping up to a 44 IDF or a 45DCOE twin carb system.Max choke size on a 40 IDF is 34mm,44Idf starts with 36mm chokes,(depending on engine modifications ,valve sizes,pistons etc,tuning your engine to your needs),larger choke sizes are available in 44IDF.Stock valve sizes, intake ports,seats,intake manifold all need to be modified in order to take advatage of the increased cfm on a 44IDF or 45 DCOE size carb,the engine will suffer from poor low speed tractibility etc... from an unmodified head even with high compression pistons and after market camshafts.40 IDF is best for engines without big valve heads.44IDF,45DCOE modified big valve heads.These are the largest twin carbs that can be used on these engines with good results(44IDF,45DCOE).

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