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#1 lawn bowls

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Posted 11 March 2021 - 01:26 AM

i just brought a brawler 750 double pumper no choke brand new i put on a aeroflow cotton air filter the smallest one i think its about a 6 3/8.it dosent have the breatherable top where the carby stud goes through.its all factory setting on idle sometimes there is little bit of black smoke comes out on idle but it preforms very well no hesitation.could the small air filter be choking the carby on idle.



#2 Dr Terry

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Posted 11 March 2021 - 07:19 AM

It won't be the air filter. Think about it, if it's a restriction at idle, it will be a major restriction at revs, it would be un-driveable.

 

It's probably more to do with float level, jetting or idle mixture settings.

 

Dr Terry



#3 myss427

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Posted 11 March 2021 - 07:26 AM

Adjust mixtures at idle, but a small air filter like that will rob heaps of power, need a 14 inch minimum for a healthy V8. Defeats the purpose of putting a good carby on in the first place.



#4 hanra

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Posted 11 March 2021 - 08:25 AM

You might have to pay Hunters a visit and get it on the dyno before the season kicks off.



#5 rexy

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Posted 11 March 2021 - 03:09 PM

You should look up the airflow requirements for your engine and fit a correct size filter.

What displacement is your engine?



#6 UCSLE

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Posted 11 March 2021 - 05:33 PM

check the float levels

I just bought a brawler 650dp and on initial start up the float level was too high

 

the instructions say the float level was set with a fuel pressure of 6.5 psi and that a higher fuel pressure will cause a higher float level

 

haven't been able to tune it yet as , need get it out of my shed so i don't gas myself out and its raining

 

a small filter wouldn't be the problem 



#7 lawn bowls

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Posted 11 March 2021 - 10:28 PM

check the float levels

I just bought a brawler 650dp and on initial start up the float level was too high

 

the instructions say the float level was set with a fuel pressure of 6.5 psi and that a higher fuel pressure will cause a higher float level

 

haven't been able to tune it yet as , need get it out of my shed so i don't gas myself out and its raining

 

a small filter wouldn't be the problem same here first start up the float level in the primary was to high.



#8 rexy

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Posted 12 March 2021 - 05:55 PM

check the float levels

I just bought a brawler 650dp and on initial start up the float level was too high

 

the instructions say the float level was set with a fuel pressure of 6.5 psi and that a higher fuel pressure will cause a higher float level

 

haven't been able to tune it yet as , need get it out of my shed so i don't gas myself out and its raining

 

a small filter wouldn't be the problem 

The small filter will be slaughtering a whole bunch of your horses though.



#9 lawn bowls

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Posted 12 March 2021 - 11:58 PM

The small filter will be slaughtering a whole bunch of your horses though.

yes i know about that.when i take it to the drags ill be taking the air cleaner off cause the drags where i race has high altitude



#10 rexy

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Posted 13 March 2021 - 07:35 AM

You will make more power with a properly sized filter than with no filter. 
Is clearance an issue?



#11 lawn bowls

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Posted 13 March 2021 - 09:23 AM

You will make more power with a properly sized filter than with no filter. 
Is clearance an issue?

clearence is a bit of a issue but not a big problem my bonnet does close there is a slight marks on the bonnet and the top of the air filter



#12 lawn bowls

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Posted 13 March 2021 - 09:25 AM

You might have to pay Hunters a visit and get it on the dyno before the season kicks off.

hi brad ill get the car tuned up there on some quiet back roads air is thinner up there completly different to home.



#13 hanra

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Posted 13 March 2021 - 11:43 AM

It’s only 500m higher.

#14 lawn bowls

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Posted 13 March 2021 - 09:35 PM

It’s only 500m higher.

thats a big difference mate i know a car at the drags 10.3 seconds went to central queensland 9.9 seconds.



#15 hanra

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Posted 14 March 2021 - 01:45 PM

How do the other 200 entrants tune their cars?

#16 lawn bowls

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Posted 15 March 2021 - 02:05 AM

How do the other 200 entrants tune their cars?

they can tune there car anywhere it will still preform cars will always be slower at high altitude than at lower altitude.in both et and mph.



#17 rexy

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Posted 15 March 2021 - 01:48 PM

How do the other 200 entrants tune their cars?


The clever ones have portable weather analysis equipment and know how to tune to suit.



#18 lawn bowls

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Posted 15 March 2021 - 04:57 PM


The clever ones have portable weather analysis equipment and know how to tune to suit.

the pros do have weather stations with ecu you can make changes by looking at the previous run and make adjustments with a carby take out number 1 spark plug at the end ofthe race and check the colour to see if if rich or lean.






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