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131mirafiori home => The Garage => Topic started by: demiru on July 02, 2014, 08:53:48 AM



Title: 40 IDF VS 44 IDF for 131 Abarth Replica
Post by: demiru on July 02, 2014, 08:53:48 AM
Greetings from Istanbul everyone!

(http://i116.photobucket.com/albums/o11/demiruyar/Mobile%20Uploads/3P4A0597_zps545144aa.jpg) (http://s116.photobucket.com/user/demiruyar/media/Mobile%20Uploads/3P4A0597_zps545144aa.jpg.html)

Just got my 131 2.0 TC and I'm pretty stoked about it and she looks marvelous next to my GT3:) after driving it stock for some time I decided to buy some engine parts while the car is getting totally stripped out for restoration..

I have come across with a complete 40 idf with all the manifolds etc.. And the guy who sells it does not have the 44 in stock..

Is there too much of a difference between them? Should I go with the 40 idf kit or is it really recommended step up the game with the 44's?

Regards,
Demir



Title: Re: 40 IDF VS 44 IDF for 131 Abarth Replica
Post by: POQ 131 on July 02, 2014, 11:39:40 AM
Hello demiru.
If you are not putting some radical cams in that 2.0 litre & porting & going big on the valves & exhaust then 40mm carbs are a good upgrade.
More dependant than 40 or 44 is what size choke tubes the carbs have in them.
I have three sets of carbs for my 18RG Toyota 2.0 litre twin cam motors. Two are 40 mm Mikuni Solex side draughts, one with 38 mm chokes & the other set have 32mm choke tubes. The other set is 40mm Dellorto's  with 36 mm choke tubes.
Now what I am saying is that there is a lot to be done with choke tube size & jet size variations in a 40mm carby on a 2.0 litre with mild or wild cams without having to go to 44 or 45 mm.
If you buy new carbs do some more research on what the other hot up bits you put in the motor are going to work in best balance with & have them choked & jetted to suit.
It is all about balance & tunability for the purpose that the car will be used. Not just hogging everything out to the biggest hole it can take. If your carbs are too big you just get a massive flat spot down low in revs & a big gulping induction Gock. I just made that Gock word up because it is like the sound it makes of a hen chocking on dry grain. Loss of induction velocity & can't breath in properly.
O.


Title: Re: 40 IDF VS 44 IDF for 131 Abarth Replica
Post by: demiru on July 03, 2014, 07:02:32 AM
Thank you for your advice! Cheers