stock rev's after impeachment

[mike75925]

hf 6.5 is said to do 3600 bone stock. i've yanked the governor, swapped heads, straight pipe, removed paper element from air filter, stiffer springs, longer rockers, flat bottom valves. i think that is all i have done. 50 wt oil, mid grade fuel. 10/62 on sprockets. i top out according to my schwinn 12 function comp at 21mph ~=3700rpm. plenty of umph, any ideas? if this is my true revs then i will venture to do some porting, adjustable jet, trim fins etc.

 

[jr dragster T]

Does the engine sounds like its cranking out RPM or just loading up?

 

[skid20]

if you are using the stock carb you'll get better performance out of 87 octane fuel. I think you should be getting at least 38-3900 rpm out of that engine.

What tire size are you running with?

 

[mike75925]

she sounds and runs strong. no missing, no hesitating, idk

 

[mike75925]

http://www.affordablegokarts.com/performance_basics.php

 

[Rickracer]

You'd better get some lighter weight oil in there, that is a "splash lubrication" engine, they don't like heavier weight oils much, the splash doesn't seem to get where it needs to go very well. If you haven't advanced the timing yet, that should probably be one of your next moves. I've got a GX 240 that I made a 1" OD header for, using an old SBC racing valve cover breather for an air filter, removed the governor, and advanced the timing, still using the stock carb for now, but drilled the main jet a couple thousandths oversize. I've trashed a coupe of rods in it, and last time I replaced the rod and the crank with good used ones, while i had it apart, I ported the head a little bit, (just cleaned up the short side radius on intake and exhaust), and shaved it about .060". Now it's a BEAST, and turns just over 6000 rpms.

 

[mike75925]

i'm using about a foot of 1" aluminum on oe flange

 

[vandancouver]

i have a 5.5 1984 engine that is almost stock and i get clocked at 36 mph..why is yours only doing 21?

 

[mike75925]

beats me

 

[vandancouver]

lol oh.