more torque

[wildfaye]

You can also change the position of your maximum torque by changing the length of your intake manifold runners.

from the space in our engine bays, i reckon its not really possible.

what about the length of exhaust manifolds? i heard that the lenght of it will also affect the range of the max torque?

our stock exhaust manifolds are pretty short, read somewhere that short ones are tuned for high end, so does it mean that longer ones are better for mid to low end?

[dannyboyau]

danny i love the way you say "the easiest way" ...

I probably should have said the easiest way to get big increase in torque,

yea fitting forced induction is not easy but is easier then stroking the engine or fitting variable intake runners

[RichardH]

Hi Danny.

The FTO powerplant *has* variable intake runners! But you took out the engine and put in a different one, so dunno what you've got! hehe.

There are servos that open and close at different rpm points in the 6a12 donk, all designed to squeeze the most out of it.

- Rich

[MADFTO]

*nods* Rich is right. Each runner has a butterfly valve that is controlled by the ECU dependant on the RPM. I'd honestly totally forgot about this =)

[dannyboyau]

Hi Danny.

The FTO powerplant *has* variable intake runners! But you took out the engine and put in a different one, so dunno what you've got! hehe.

There are servos that open and close at different rpm points in the 6a12 donk, all designed to squeeze the most out of it.

- Rich

did i at any point say that the 6A12 mivec hasn't got it. i was replying about how to increase torque and the methods used.

[RichardH]

Yeah, sorry... 6a12 tunnel vision on my part!

- Rich

[efteoh]

thanks Ruchi the air filter and extractors sounds reasonably good. who here has only the extractors and air filter? are there any other extractors apart from RPW that people have tried? as i have heard very mixed review about them.


thanks guys

[ruchi]

There hasn't been any mixed reviews in relation to the performance of the RPW extractors, the issues are that they aren't finished off nicely (i.e. the weld joints are a bit messy) and that they haven't been dyno proven to show where the gains are.

Those who have them however, report that they feel the gains through the mid-range (around 3,000rpm-6,000rpm).

[FTO338]

There hasn't been any mixed reviews in relation to the performance of the RPW extractors, the issues are that they aren't finished off nicely (i.e. the weld joints are a bit messy) and that they haven't been dyno proven to show where the gains are.

Those who have them however, report that they feel the gains through the mid-range (around 3,000rpm-6,000rpm).

Well actually is the internal piping thats a bit rough, not the weld joints, which can restrict the proper air-flow.

[ruchi]

whoops, my memory failed me

[FTO338]

whoops, my memory failed me

Hehehhe it helps when i wrote the original review post.

[dannyboyau]

Yeah, sorry... 6a12 tunnel vision on my part!

- Rich

no problems mate

I actually have a 6A12 manifold in pieces (interesting how they have done it) and a 6A13 manifold cut up if you ever want to drop round and have a look give me a bell. I could also show you how the mivec works as i have a set of 6a12 mivec heads in pieces too.

[dannyboyau]

You can also change the position of your maximum torque by changing the length of your intake manifold runners.

from the space in our engine bays, i reckon its not really possible.

what about the length of exhaust manifolds? i heard that the lenght of it will also affect the range of the max torque?

our stock exhaust manifolds are pretty short, read somewhere that short ones are tuned for high end, so does it mean that longer ones are better for mid to low end?

my understanding is similar to to what you have said. On certain vehicles the length of the exhaust runners can make huge differances, I remember discussing the exhuast manifolds one night with a mate who is into the rotary tunning and he made some comments regarding how they where having problems with one engine because of the exhaust runner lenghths.

Here is a couple of passages that might help explain how the runner length works

Exhaust

Primary tube header length is tuned with the understanding that the shorter the primary tubes, the better the high rpm power will be. Each exhaust pulse creates a high-pressure wave that travels toward the collector, and once it meets the collector, is inverted and travels back toward the cylinder as a low-pressure wave. It is this lower pressure wave that helps scavenge exhaust out of the cylinder during the overlap period, and helps efficiency. Street driven cars that require engines with more torque and response do better with longer primary tubes.

Inlet

When the intake valve closes suddenly, the airflow stops and forms a column or a high-pressure wave that makes its way back up the manifold from the cylinder. At the end of the intake runner, at the plenum, the pressure wave bounces back down the intake runner. If the intake runner is just the right length, the pressure wave can be tuned to arrive back at the intake valves just as they are beginning to open again and the extra pressure helps force more air in to the chamber

one thing that is often needed to be thought about is that you need to make sure that each change you make works with each other as you can easily make changes that are detremental to your engines performance if you are not careful

[GWIDO]

me me me, yes please, would love to have a look at the inside of the heads. I think i got your number somewhere, mind if i ring you?

[dannyboyau]

well i know richard has it as i got a calender from him, who are you. If you are in Perth anytime I will show you, just call.