44 idf' jeting
Super1302 - October 25th, 2012 at 08:09 PM
firstly.
i have a 2332cc running fk10. los panchitos heads (40 x 35) and i am wondering about my jetting. i have 60 idles. 135 main jet. 175 airs. i had a chat
with Dave Becker, he says i got to go bigger. will 165's do or is it too big.
secondly.
i have some 120 airs i could get re-drilled to what is required. is 200 too big?
thirdly
Dave does not know that i have the 165 airs, i had to look around and found this size.
could it be too big. i have 135 airs spare too.
and last of all, this came along as my temps went to 108 Celcius. and had popping out the carbs i think.
any idea's in the mean time for what i should use before i get back to Dave possibly tomorrow.
Cheers
Craig Torrens - October 25th, 2012 at 08:56 PM
what size venturi's are you running, 36mm ? go a 145 main with the 175 airs.
was it popping at idle ?
vassy66T1 - October 25th, 2012 at 08:59 PM
What venturis are you running?
Go a couple of steps in main if you think (e.g. 145) but the others won't be far off.
I don't think your airs will be far off.
Super1302 - October 25th, 2012 at 09:06 PM
i have 36 vents, does not really pop at idle.
ok will ry and get some 145's.
find out tomorrow.
cheers
cesiumfrog - October 26th, 2012 at 07:56 AM
i,m thinking you may need bigger than 145 mains
idle and air may be ok
but really need to check plug colour or use AFR gauge to see what is really happening.
Sides - October 26th, 2012 at 09:55 AM
135 mains and 175 airs is a good match depending on what the cam is like, and like Craig says a 145 main could suit if you keep the same air jet.
Basically going up on the main jets without increasing air jets will make things richer from transition onwards (2500-3000 rpm and up). Increasing air
jets causes the mains to come on earlier - richens the mid range (3000-4000'ish) but potentially leaning out above that.
60 idles could even be on the large side and may be masking that your mains are too small - if it's soggy below 2500 (but doesn't pop) then maybe
try a 55 idle.
If it pops anywhere when under steady throttle that generally means either an exhaust leak or lean at that point.
Popping when you stomp it points towards not enough accel pump.
vassy66T1 - October 26th, 2012 at 04:48 PM
More complete info from Dave.
Half baked effort from me and the rest 
(I am serious: good info Mr Sidery)
Super1302 - October 26th, 2012 at 05:55 PM
Fella's, thanks for the replies.
Well, the spare 135's i had were redone to 145's. PERFECT
no popping at all, accelerate and whammo.
i still might have to go down to 55's on the idle.
but one thing. it is hard to get it to idle by itself at the start
whats the answer please to this. i have heard if the engine does not idle
and you adjust your idle screw in to get it up it might mean
that the idles are too small and running lean?
got me stumped. maybe too much fuel at idle i am thinking, is that possible.
Paul.
colin - October 26th, 2012 at 07:37 PM
| Quote: |
Originally
posted by Super1302
Fella's, thanks for the replies.
Well, the spare 135's i had were redone to 145's. PERFECT
no popping at all, accelerate and whammo.
i still might have to go down to 55's on the idle.
but one thing. it is hard to get it to idle by itself at the start
whats the answer please to this. i have heard if the engine does not idle
and you adjust your idle screw in to get it up it might mean
that the idles are too small and running lean?
got me stumped. maybe too much fuel at idle i am thinking, is that possible.
Paul.
|
Stop guessing and get your car on a dyno.
You will get it close with your ear and your backside but why spend mega bucks on your engine and not spend a little on a dyno tune to get max
performance for your engine.
Do yourself a favour dyno tune it, you,ll love the results,
best of luck.
Cheers Col
Super1302 - October 26th, 2012 at 08:25 PM
will have to i guess
Gracey - October 27th, 2012 at 12:54 PM
| Quote: |
Originally
posted by Super1302
Fella's, thanks for the replies.
Well, the spare 135's i had were redone to 145's. PERFECT
no popping at all, accelerate and whammo.
i still might have to go down to 55's on the idle.
but one thing. it is hard to get it to idle by itself at the start
whats the answer please to this. i have heard if the engine does not idle
and you adjust your idle screw in to get it up it might mean
that the idles are too small and running lean?
got me stumped. maybe too much fuel at idle i am thinking, is that possible.
Paul.
|
When you say at the start do you mean cold motor??
If so then your idle jets are close to correct assuming you mixture screws are out 1.5 to 2.5 turn (ball park figure).
You have to remember cold motors love fuel, that's why chokes or cold circuit enrichment circuits work so well.
As the motor warms up it needs less fuel.
How does the motor respond at idle when warm?
Super1302 - October 28th, 2012 at 06:10 PM
| Quote: |
Originally
posted by Gracey
| Quote: | Originally
posted by Super1302
Fella's, thanks for the replies.
Well, the spare 135's i had were redone to 145's. PERFECT
no popping at all, accelerate and whammo.
i still might have to go down to 55's on the idle.
but one thing. it is hard to get it to idle by itself at the start
whats the answer please to this. i have heard if the engine does not idle
and you adjust your idle screw in to get it up it might mean
that the idles are too small and running lean?
got me stumped. maybe too much fuel at idle i am thinking, is that possible.
Paul.
|
When you say at the start do you mean cold motor??
If so then your idle jets are close to correct assuming you mixture screws are out 1.5 to 2.5 turn (ball park figure).
You have to remember cold motors love fuel, that's why chokes or cold circuit enrichment circuits work so well.
As the motor warms up it needs less fuel.
How does the motor respond at idle when warm?
|
yes it does run well once the engine is warmed up, idles at about 1000rpm.
i think it needs to though with 540 thou lift at 308 duration.
yeah all is good, will get a dyno tune when the time comes.
Cheers for the input.