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Un- trail converting an iqr440

A
Nov 28, 2013
1
0
1
33
So I have a trail converted iqr 440 (2006) has the timing box. 92 octane heads, no hot start button, v3 reeds, and oil injection. I want to run the high comp race heads. What all would I need to change to do that. Obviously the heads, but what jets do I need to run ect... And what should I do with the timing box? Still has the race clutching as far as I can tell almond red spring ect...

Right now i run 93 non Oxy with the timing box on f
 
T
Jun 27, 2008
2,646
222
63
Bend, Oregon
Js powersports has a good jetting spreadsheet in there website, clutching too.

You should be able to run the race head with the oil injection if you want just bump up the octane, no much else to do.

Can't help you much with the ignition box, I run mine on c with my 600.
 

sledking

Well-known member
Lifetime Membership
Dec 13, 2007
617
49
28
Central MN
When running the high comp head make sure to run high octane fuel at least 110 or higher. and when running higher fuel the rule of thumb is to lean out the jetting roughly 10 sizes. I would try and find a manual and see what the timing curve exactly is with the timing box you have and how much each letter advances or retards the timing. I know there is differences in boxes and ECUs. I am running my 600 on E but I have the motor ported and head slightly shaved. I still get by on 91 non oxy, but i am border line. You will have to do some trial and error and advance it one click at a time and then do plug check and see where your timing line is on the plug
 
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