Install trumpet inside plenum. Any difference???

[Dayline668]

longer velocity stacks aid in lower-end torque, like what dayline sed

with/without trumpets, without it the air entry will be rough/messy, with it, response definitely improved, and seemed more eager to get off the line as well, just felt better all round

dcoe40/4g15 user here but applicable here as well haha

Weber user le.. come share ur setting..

 

[tofu_manic]

chokes = 32mm
main jets = 135
air correctors = 180

those are the specs if i remember them correctly haha

4g15 stroked to 1.6l, 272 cam, cdi ignition and other misc. stuff

 

[levin818]

I have plug in a set of trumpet in my ride last week. Its black in colour, no brand, length is similar to IMEC's (~1"). The result:
1) low end torque, from 3000rpm-5000rpm, was reduce a little bit, but not so significant if you pull from stand still. However, if you were at 3000rpm at 3rd gear and suddenly floor the fuel due to demand, you will notice the drop in torque.
2) Engine started to pull "a little bit" from 5000rpm till 7900rpm, linearly.

My ride set up - BT engine (balance) & 4-throttle, SVT wiring and ECU.
Perhaps if you compliment the set up with piggy back ECU, the feel will be more steam up

 

[Dayline668]

chokes = 32mm
main jets = 135
air correctors = 180

those are the specs if i remember them correctly haha

4g15 stroked to 1.6l, 272 cam, cdi ignition and other misc. stuff

Ever dyno..? how many hp gain..?

 

[tofu_manic]

I have plug in a set of trumpet in my ride last week. Its black in colour, no brand, length is similar to IMEC's (~1"). The result:
1) low end torque, from 3000rpm-5000rpm, was reduce a little bit, but not so significant if you pull from stand still. However, if you were at 3000rpm at 3rd gear and suddenly floor the fuel due to demand, you will notice the drop in torque.
2) Engine started to pull "a little bit" from 5000rpm till 7900rpm, linearly.

My ride set up - BT engine (balance) & 4-throttle, SVT wiring and ECU.
Perhaps if you compliment the set up with piggy back ECU, the feel will be more steam up

not 'perhaps' but 'confirm' the feel will be more steam hehe

Ever dyno..? how many hp gain..?

nope never dyno b4, but hp tarak byk lah sohc 4g15 onli hehe

 

[Dayline668]

dun say 4g15 only, datsun A15 stroked 1.7 weber can chunk out 200hp le...

 

[tofu_manic]

wow 1.7l with 200 hp, sohc isnt it? im guessing that is an all-out race engine with massive duration/lift cams

mine is more of a streeter, not bad low and mid but kinda breathless up top

oh well...getting kinda off topic here LoL

tenks for the a15 200hp info, didnt noe that, pretty impressive

 

[muzhaffar]

if we put the trumpet inside the plenum, the air stream will be distributed evenly or not?
because the air will enter from one side and all the trumpet will face the plenum..
logically, at high engine speed where air inertia is high, the last plenum will get higher air flow rate compare the first one..
but the injector is tuned to supply same amount of fuel for all 4 cylinder. however, because the air supply is not even, the a/f ratio will nat same for each cylinder.perhaps there will be one or more cylinder that will running lean.just like what happen of earlier version of 3s-gte engine based on what i read on wiki..
dont know either it is true or not..
just my opinion..
my concern is that does it will give side effect if we put trumpet inside plenum?

 

[tofu_manic]

to be honest, custom-ing an intake plenum is quite risky work...have to think about plenum volume / shape / trumpet size / length / distance from plenum wall / airflow@ X rpm / etc. etc.
ie. things i totally am clueless about

 

[pcmoddingmy]

Bro muzhaffar, stock setup already got trumpet, but the shape is like elephant trunk to reduce the induction roar and is made of plastic(or rubber). So I believe there shouldn't be any issue installing trumpets inside the plenum, unless it is longer than 2". Besides, I understand that air doesn't travel in one direction and the plenum is designed to pull air from the bottom portion. So logically it shouldn't be any problem. Besides, you can test it out yourself by cleaning the plugs and checking each plugs individually after a few runs with the trumpets. If all of them are in similar color, then the airfuel mixture should be similar on all cylinder.

 

[muzhaffar]

to be honest, custom-ing an intake plenum is quite risky work...have to think about plenum volume / shape / trumpet size / length / distance from plenum wall / airflow@ X rpm / etc. etc.
ie. things i totally am clueless about

it is really hard to investigate the airflow just by guessing technique..
need to use any computational fluid dynamics software such as star ccm etc to study the flow for better air distribution and pressure..

Bro muzhaffar, stock setup already got trumpet, but the shape is like elephant trunk to reduce the induction roar and is made of plastic(or rubber). So I believe there shouldn't be any issue installing trumpets inside the plenum, unless it is longer than 2". Besides, I understand that air doesn't travel in one direction and the plenum is designed to pull air from the bottom portion. So logically it shouldn't be any problem. Besides, you can test it out yourself by cleaning the plugs and checking each plugs individually after a few runs with the trumpets. If all of them are in similar color, then the airfuel mixture should be similar on all cylinder.

agree with the solution of checking each cylinder spark plug..
but is there any logical reason why the long trumpet give better low end torque?
is it because it's air velocity inside trumpet is higher hence produce higher inertia than short one during low rpm and at high rpm it's surface resistance decrease the volumetric efficiency hence reduce the power produce?
just my guessing
dont shoot if i'm wrong..

 

[pcmoddingmy]

agree with the solution of checking each cylinder spark plug..
but is there any logical reason why the long trumpet give better low end torque?
is it because it's air velocity inside trumpet is higher hence produce higher inertia than short one during low rpm and at high rpm it's surface resistance decrease the volumetric efficiency hence reduce the power produce?
just my guessing
dont shoot if i'm wrong..

i guess you're right bro... but it beats me as for why trumpet length plays difference in the torque output. to understand this, we'll need to learn more on the functions of velocity stacks. take a look at;
http://www.velocity-of-sound.com/velocity_of_sound/calculator1.htm

also note that the mouth of the trumpet also plays important role as well, eg; bellmouth vs sharp edged mouth. not forgetting the inner diameter and mouth diameter as well. too much calculation for me i guess. so i just follow the most common and tested setup based on tuners and end-users as well

 

[ajik8953]

prem,remember me?SE dat use rubber trumpet @ Teluk Batik Gath..

so,how's ur setup during using steel cup trumpet?

found dat,after using dis kind of open pod..my FC quite high n engine oil dried too quick..but,can feel the power la...

 

[tofu_manic]

interesting stuff

ive read sumwhere b4, the effect (somehow la i 4got the reasoning/blah theories hehe) adding to the length of the trumpet is like adding to the length of the intake manifold runners, where the longer the runners are, the earlier the powerband is

 

[muzhaffar]

prem,remember me?SE dat use rubber trumpet @ Teluk Batik Gath..

so,how's ur setup during using steel cup trumpet?

found dat,after using dis kind of open pod..my FC quite high n engine oil dried too quick..but,can feel the power la...

your FC quite high maybe because you floor the padal so much..

another question, why the engine oil dried quickly if we use trumpet?..
and what is the effect of not draw the blowby gases inside the crankcase into the intake manifold?
because when we use trumpet, the breather hose is not connected to the intake manifold anymore..
the benefit is the oil mist will not trapped inside the intake manifold..
the there may be bigger dust particle will be sucked into the engine..but the itb suction sound is priceless...
can notice that the intake roar is different when the vvt is on..

 

[1JZtezza]

Trumpets are basically to aid air flow.If torque increases its a bonus and its because of better efficiency in the combustion.It may help move the torque curve earlier or later (in RPM range)
It would be better if the intake manifold and head are port and polished.Getting the right size(diameter) is also important.This sounds noobie but if say u put trumpets meant for weber 45 onto a weber 40 it wont work and vice versa.
If running with cams;the cams pretty much determine the rpm range and u choose the length but the restriction will come from the air filter and piping to the plenum.
After taking care of the intake side do take care of the exhaust side for better results.

 

[muzhaffar]

if we can have electronically controlled variable trumpet length, we can get better torque curve throughout various range of engine speed..
maybe suitable to be final year project topic..

 

[pcmoddingmy]

prem,remember me?SE dat use rubber trumpet @ Teluk Batik Gath..

so,how's ur setup during using steel cup trumpet?

found dat,after using dis kind of open pod..my FC quite high n engine oil dried too quick..but,can feel the power la...

Ya bro... i remember ur ride... quite wicked.
Setup using stainless steel cup trumpet is quite good... but when tune with emanage seem to improve FC a bit (or no difference). Power wise good also and easily scare away people a few meters in front of you too...

bro muzhaffar, variable trumpet, good idea.. but i think toyota done something similar before with TVIS.
http://en.wikipedia.org/wiki/Tvis

 

[muzhaffar]

Ya bro... i remember ur ride... quite wicked.
Setup using stainless steel cup trumpet is quite good... but when tune with emanage seem to improve FC a bit (or no difference). Power wise good also and easily scare away people a few meters in front of you too...

bro muzhaffar, variable trumpet, good idea.. but i think toyota done something similar before with TVIS.
http://en.wikipedia.org/wiki/Tvis

TVIS is toyota variable intake speed..
it is done by having 2 intake passage for each cylinder
during low rpm, one of the passage will be close so the effective tract diameter will be smaller and as a result, higher air flow speed and inertia. at high speed when it require higher volumetric flow rate, it open the 2nd passage and the effective area of intake port will increase hence allowing more air to flow in. so, i can say that it likely variable intake tract diameter. the intake length is still the same..
TVIS help improving torque at low rpm but it reduce some of the volumetric efficiency at higher speed range due to the split passage

 

[nnik]

anything to do wift this ????

 

[Dayline668]

anything to do wift this ????

That is for ''Drive By Wire'' throttle bro.. not for oldschool cable throttle.. Its to make throttle respond sharper n more accurate, can also save fuel by its setting, gently adjust throttle even u floor it.

---------- Post added at 07:45 PM ---------- 6 hour anti-bump limit - Previous post was at 07:35 PM ----------

TVIS is toyota variable intake speed..
it is done by having 2 intake passage for each cylinder
during low rpm, one of the passage will be close so the effective tract diameter will be smaller and as a result, higher air flow speed and inertia. at high speed when it require higher volumetric flow rate, it open the 2nd passage and the effective area of intake port will increase hence allowing more air to flow in. so, i can say that it likely variable intake tract diameter. the intake length is still the same..
TVIS help improving torque at low rpm but it reduce some of the volumetric efficiency at higher speed range due to the split passage

Mostly mod by removing it n port it bigger if not change ae92 bluetop head. After removing TVIS FC confirm much more higher. Tested.

Variable trumpet.. interesting.. got me thinking now...

 

[pcmoddingmy]

TVIS is toyota variable intake speed..
it is done by having 2 intake passage for each cylinder
during low rpm, one of the passage will be close so the effective tract diameter will be smaller and as a result, higher air flow speed and inertia. at high speed when it require higher volumetric flow rate, it open the 2nd passage and the effective area of intake port will increase hence allowing more air to flow in. so, i can say that it likely variable intake tract diameter. the intake length is still the same..
TVIS help improving torque at low rpm but it reduce some of the volumetric efficiency at higher speed range due to the split passage

FYI, TVIS is Toyota Variable Induction System.
As I said, its similar... and changing the trumpet length would cause similar outcome too.
Perhaps you could consider looking into ACIS and VLIM. Refer below:
http://en.wikipedia.org/wiki/Variable_length_intake_manifold
http://en.wikipedia.org/wiki/Acoustic_Control_Induction_System