need advise on size of piping

[bfb515]

helo there

im using wira 4g15 manual trans with weber dcnf 40 carb + knn air filter, powerzone cam, and powerzone 421 extractor

i need advise for the right/optimum piping size
rite now im using 2' piping, original route + 2' straight flow muffler
very hard to achieve top speed
rpm at about 5k something goes wrong
the car wont increase speed
feel like choked
have to release pedal little bit then press again then ok sikit
but then
its sucks

any opinion to increase the performance of my car?pick up?top speed?

tq in advance
:)

 

[AD_EG]

1.7" piping... 2.0 is too big bro.

 

[bfb515]

thanx ad

is it the size of the piping that cause my car to get that prob at that 5k rpm??
or other possible causes?

btw
wheres a good exhaust/piping shop that can make 1.7' piping?
most of the shop i go onli have 1.6' or 2.0' onli
any suggestion??
im living in klang

tq

 

[DanzEterna]

yup, the accurate piping size is 1.65"

 

[tigger5251]

you should use 2" piping with a 2" inlet S-Flow. change your extractor to tuned 4-1.

4-2-1 is for torque NOT horsepower. since ur 4G15 with weber produces alot of torque and power on the low revs, u should focus on mid and high revs. u should also swap a 272 cam with a good external fuel pump to ensure good power.

But the fuel is gonna be high about 30sen per-km, but at this stage, you can screw alot of cars from putra to altis (where the fun starts)

 

[bfb515]

thanx danz n tigger

due to budget, i dont think of changing aythg else, except the piping rite now...

seems that 1.65' / 1.7' is the most suitable size for the current set up rite??..
any recommendation where to do the piping??
any good shop recommended??

thanx

 

[tigger5251]

thanx danz n tigger

due to budget, i dont think of changing aythg else, except the piping rite now...

seems that 1.65' / 1.7' is the most suitable size for the current set up rite??..
any recommendation where to do the piping??
any good shop recommended??

thanx

The setup u mentioned, is economical + performance. Best is using 2" pipe (inlet 1.7")

If u choose 1.7" piping ur inlet is only 1.5" (too small)

But is a MUST to use a S-Flow if u want topspeed.

 

[bfb515]

ouh ok2

so
all of the recommendations size of 1.65'/1.7' piping mentioned above
its the inlet or outlet??

 

[DanzEterna]

if simple piping, can just go to wai heng or wei yip,
if u wan performance or complicated ones, go to ijal exhaust or jin hiang at somewhere around batu caves.