Rebored Throttle Body

[flamefox850]

hi guys,

i just wanted to know ..is it true if we rebore our stock TB the the engine get poor idle or idle 'gila' ???

why is this happen ? is it becos of rebore the TB then not change the throttle plate (butterfly)??

need comment

 

[dolly]

if dont change the butterfly, wont air get through it even if its closed?

 

[szekeiemme]

if nvr change butterfly rite.. air still go in cuz the diameter of the TB is bigger already.. but wut i heard from supertEC88 mayb idling is crazy n mayb like highcam.. ekekke cun la..!! test test!

 

[flamefox850]

yeah...that's what i'm thinking of. sometimes people rebore TB then dun change new custom butterfly..that's why idle gila is it ?

so, if i rebore the TB than change to bigger butterfly also...the idle no gila ?? sure ?

 

[boggysv]

when u enlarge the hole without enlarging the throttle plate, air flows across it and gets it's way into the combustion chamber. They will produce power and hence, ur rpm rises.

the ecu will sense this increased rpm and tries to correct it (one way or another) this is the cause of the crappy idiling and very likely to waste fuel.


I would not recommend it for a car since enlarging the TB shifts the power band higher.

but if u want to make a maxed out engine, go for big TB, big diameter but short manifolds!!! sure demm keng wan!!

 

[boggysv]

my 2cents...pls advise if anything is wrong

 

[flamefox850]

Originally posted by boggysv@Jan 30 2005, 22:33
when u enlarge the hole without enlarging the throttle plate, air flows across it and gets it's way into the combustion chamber. They will produce power and hence, ur rpm rises.

ok dude...i know about this.

ok..now IF i rebore my stock TB to larger bore AND with new LARGER custom built throttle plate aka butterfly, is the idle still bad ??? assuming no leak

 

[boggysv]

shouldnt be.

but i assume ur engine wont be responsive/ feel laggy while it's on the lower revs.

pls correct me if i'm wrong


but why u want to rebore and custom make a throttle plate? so susah.
Y not just get another TB?

 

[flamefox850]

yah..i think to get bigger TB also...but i dunno if the installation will make me feel headache or not haha.

the problem might be
-throttle sensor
-vacuum line
-throttle socket ?

my car is errr L2 hybrid and using stock L2 TB, and L2 doesn't have throttle sensor actually. it ave but only got ON and OFF. no 10% on, 20% on WOT whatsoever lah.
if upgrade to other TB..how about the problem ? any advice ?

p/s: about the tapak..no problem lah

 

[boggysv]

sorry...dunno much about L2.

since u said u dun have a throttle position sensor, I dont think it will be a problem.

I also dont understand why are u worried about ur vacuum line?

I think getting a piggyback or an aftermarket ECU might help u alot.
sorry to say,but just an open/closed reading for throttle positon seems a lill primitive.

 

[flamefox850]

hahahhahaa yaa a bit promitive...u know la L2 is produce in 1992 wooo.

hey, in this case...can i use TB such as wira/satria 1.6 TB no worries ? what have we consider about upgrading a TB..other than the size and flange ?

 

[boggysv]

u wont be releasing the full gain of the larger TB if u keep the manifold as it is. Get a matching intake manifold as well :P

 

[flamefox850]

yaa yaa..but then...no problem upgrading ANY tb ???

*i'll port a bit of my intake manifold. not going to custom made...very difficult to measure. worng measurement..worst performance haha

 

[boggysv]

i really dunno ler...my car stock only...onli modify ICE n rims.

Those i post above i read from book wan
http://www.mph.com.my/search/nsearch.cfm?do=detail&pcode=1859604358
Really usefull!!!

 

[flamefox850]

ahh ok ok...thanks a lot.

ok anybody else want to comment pls