[reggie450]

I have been looking for cheap options to get some power from my engine. I blocked the inlet manifold where it joins across the front by replacing the gaskets with alloy plates, to shorten the distance of air travel. It seems to have given power lower at 2500 to 3500 rpms. Fuel economy is also better. Does anyone have other cheap mods?

[Gwagensteve]

Did you do this with any theory in mind or was it "something to do"?

Sorry of this seems dismissive, I say this only because decreasing inlet runner length increases high RPM power, longer inlet runner length increases low end torque. I don't think you've actually changed the airflow path length) at all, you've just separated each bank. I'm not really sure what that would achieve, but in the absence of any actual tech, I think it's wise to assume suzuki included the balance pipe for a reason.

Anyway, you could run some calcs on inlet runner length vs torque production here.

http://www.wallaceracing.com/runnertorquecalc.php

Steve.

[reggie450]

If your not sure what this would achieve, (steve) maybe you should try it for your absent minded self. I was too busy 4wding, to run calcs. Only respond to posts if you have an aswer to the question.

[joeblow]

Does the extra butterfly on the 2.7 manifold do a similar thing?

[Gwagensteve]

reggie450 wrote:

If your not sure what this would achieve, (steve) maybe you should try it for your absent minded self. I was too busy 4wding, to run calcs. Only respond to posts if you have an aswer to the question.

Awesome tech.

Steve.

[stockman]

Yeh. Get a life Steve.

[want33s]

reggie450 wrote:

I have been looking for cheap options to get some power from my engine.

The best way I've found to get some power from any of my engines is to start them.

[stockman]

But fuel ain't cheap.

[stocker]

reggie450 wrote:

If your not sure what this would achieve, (steve) maybe you should try it for your absent minded self. I was too busy 4wFAILING, to run calcs. Only respond to posts if you have an aswer to the question.

Petrol in those motors, not Diesel... you'll get heaps more power

how dare you try and help steve... you should be ashamed...

[bigrig91]

reggie450 wrote:

I have been looking for cheap options to get some power from my engine. I blocked the inlet manifold where it joins across the front by replacing the gaskets with alloy plates, to shorten the distance of air travel. It seems to have given power lower at 2500 to 3500 rpms. Fuel economy is also better. Does anyone have other cheap mods?

My current power mod is replacing the h20a with the h25a, although it is proving to not be cheap once the timing chains and tensioners are replaced, the water pump and oil pump, the clutch and flywheel and genuine rear main seal. haha. Better be a good increase ill tell you that much!!

There is a massive differnce in the size of the hole on the h20 and h25 manifold that you blanked, the h25 is alot bigger i would say 3 times as big. Would this help or just allow better air flow?

[gypsy]

reggie450 wrote:

If your not sure what this would achieve, (steve) maybe you should try it for your absent minded self. I was too busy 4wding, to run calcs. Only respond to posts if you have an aswer to the question.

everytime I see a post from gwagon I feel the way, I no he knows alot about suzuki but sometimes I wish he would just shut up

[TheOtherLeft]

gypsy wrote:

reggie450 wrote:

If your not sure what this would achieve, (steve) maybe you should try it for your absent minded self. I was too busy 4wding, to run calcs. Only respond to posts if you have an aswer to the question.

everytime I see a post from gwagon I feel the way, I no he knows alot about suzuki but sometimes I wish he would just shut up

So you want to ignore good advice?? What are you Gen Y???

[Gwagensteve]

It's generally best for forums to discourage discussion and logic.

Steve.

[gypsy]

Have you ever done this mod to this engine steve

[royce]

gypsy wrote:

Have you ever done this mod to this engine steve

I doubt anyone with any idea of manifold theory would.




I dont even have a good idea of what the manifold looks like but perhaps by doing what you did changed the way the cylinders filled at those RPM, I bet it goes to shit somewhere else though if its 'opening' up the other end of the plenums, plenty of power has been gained by not feeding air soley into one end of a manifold

I might add too reggie, dont come in with half a story hoping for some gratification from the 15yo's and then chuck a tantrum when somebody questions why you did what you did, we have enough dicks already all the new ones get removed.

[Gwagensteve]

Quote:

Have you ever done this mod to this engine steve

No, and I never claimed to. That's the amazingly amazing thing about discussion We can all use discussion to understand more about things. I know I do.

Feel free to correct me where I have made a mistake. You've never, every replied to any thing I've ever posted before except to tell everyone how I think there's only one way to do things. Comon dude - bring the tech! Here's your chance to prove me wrong!

The OP has removed what I can best describe as a balance pipe between the two banks of the plenum, and has made some claims to the benefits.

A) Removing the pipe has shortened the length of the airflow. I don't think this is true from my experience with H20's. Do you think this is true?
B) Shortening the length of airflow from throttle body to head has increased low to midrange torque. Do you think shorter inlet tracts lead to more low end power and torque?

You'll note, I never doubted the claims of the OP. Maybe, for some strange reason they are 100% true. (No data though?) I'm only doubting the reasoning given for the improvements. Perhaps there's some other reason that removing the pipe has done something, like changing manifold vacuum at the MAP and affecting fuel trim? If so, might it be a bit random unless checked with a sideband O2 sensor?

I have looked at that pipe on the H20 cars I've worked on and wondered what its function is, but I know stuff all about flow dynamics and I couldn't see a reason that removing it would make any significant change to the performance to the motor. It's great if it does, but It would be awesome to know why, don't you think?

Of course, anyone can do anything they want and make any claim they want. You can't deny my right to question a claim though, when it flies in the face of commonly accepted fact.

Steve.

As an aside, I wonder why suzuki fitted that part if it reduced mid range torque and fuel economy, which much be the case if the OP's claim is true, no?

[gypsy]

And like i said i no u no alot about this kind of stuff never said other wise, just don't like the way you shut people down just be cause u think it won't work, and Royce he has done it he thinks it better so think he would no. And as for the no tech steve im not to good with words so I dont bother

[Gwagensteve]

Did you read what Royce wrote? I'm not sure that was what he was saying.

I never even said it wouldn't work, only that it wouldn't work for the reasons the op was claiming. What was exactly what Royce said.

This is a tech board. Not chat. If you post something in here everyone should expect to discuss it or for someone to disagree with you. That's how we learn. I want to know know why something works.

Steve.

[atari4x4]

this thread brings the lolz.

i'm sure suzuki would have spent considerable time, money & effort designing the intake manifold the way it is for a nice even balanced power delivery.

[twitchy]

reggie450 wrote:

If your not sure what this would achieve, (steve) maybe you should try it for your absent minded self. I was too busy 4wding, to run calcs. Only respond to posts if you have an aswer to the question.

Dude, do you need to borrow some Tampax??????

[fordem]

When Steve speaks, I listen; if he says something that I disagree with, which is not common because we have different areas of expertise, I will hold my tongue and go research whatever it is - I have come to appreciate, from his posts, that he is not a man to go off "half-cocked" - in this regard he reminds me of a local machinist, at whose shop I will occasionally hang out - many of our local racers use this machine shop, and my friend has a term for some of these racers - I think it's fitting here, and that's why I'm posting - many is the occasion I've stopped by and he's doing something, for example machining a cylinder head, and even to someone with my limited experience, it's clear that the work being done is absolute rubbish, and I look at him, before I can even ask 'WTF?', he'll say "try-a-ting" - he'll advise against it, but, if the customer wants it done, he'll take their money and do the requested work.

"try-a-ting" - correctly spelled - "try-a-thing" - it's when someone, in their quest for more speed, more power, will literally try something, anything to see what will happen, with little or no thought as to how the modification will provide the desired enhancement.

What's happening in this case is the "balance pipe" is being removed, the intake plenum volume is being reduced - how do these two modifications create more power - this is a fine example of what my friend calls "try-a-ting".

[Built4thrashing]

here is a pic of a H25a v6 in a 1999ish GV. Im assuming he has removed the front balance intake pipe shown in the pic.

[Gwagensteve]

That's my understanding.

I'd say it's significantly reduced plenum volume.

Here's in interesting page on designing inlet plenums.

http://horsepowercalculators.net/intake ... old-design

I'm too absent minded and too busy trying to fit a compressor under my seat to bother with any actual calculations, but 30 seconds of googling indicated that a rough guide for ideal plenum sizing is 1.25-1.5X engine capacity, but that most stock manifolds are 50-80% of the capacity of the engine My guess is this is a cost and packaging constraint.

I'd say that the balance pipe would have to have maybe 750cc of capacity? I wonder what dropping that much plenum capacity has done? Sure it's not all that good?

I wonder if it has restricted cylinder filling at high rpm (hence why the midrange looks fatter) and why the computer has backed some fuel out at cruise because the car was running rich due to the reduced cylinder filling?

Steve

[dhula]

If the OP has removed the crossover pipe and put banks in it's place as per the pic of B4T above then I'd think that what he has done is make 2, 3cyl engines joined at the crank instead of having a V6 (really really simply speaking). This will change a bit at the farting end where I presume the exhaust is similar to a GV and join together somewhere underneath the car.

If this is the case then perhaps what is happening is that each bank does in fact haveenough of a plenum to suit the size of the "engine" it is feeding which will be aprox 1 litre each and the exhaust, should it be joined, is assisting in scavanging the gasses away allowing for a more complete A/F load being fed into each sylinder.
If this is the case then perhaps the ECU is not trimming fuel but in fact leaving things as they are but better performance/economy is being achieved by better efficency in the combustion chanber.

I have no evidence of this being the case nor have I done any calcs to prove it on the Suzuki V6, but I was thinking back to the day when I we did a lot of work on a modded towrana that had twin exhaust (3 cyls per pipe, no cross over) and twin carbs (inlet manifold was custom feeding 3 cyls and no crossover) and it went pretty well. It did take a lot of extra work on ign timing (custom weights and springs in the dissy) and fueling (much work on the twin 350 holleys) to get it running sweet tho. Sounded cool as to.

[Gwagensteve]

It's pretty common to run V engines as two inline motors - A heap of Euro manufacturers do it, especially when they have twin turbo V motors.

And as an aside, a couple of years ago a class 1 off road race buggy was running a BMW M5/M6 V10, set up with two MoTec computers running one bank each.

However, to do that, my guess is you're going to want two independent throttle bodies and plenums, like this:





In the case of the H series motor, the plenum uses a shared throttle body, so it's just one plenum.



These are 2.5 and 2.7 manifolds side by side.

I'd say removing the "balance pipe" is going to very significantly reduce plenum capacity, and it's hard to imagine the engine is going to work noticeably better with cylinders 1&2 at the end of a dead end "log", unable to draw air from the volume of the balance pipe.

Steve.

[Built4thrashing]

The only advantage i could see from removing the balance pipe and blocking it off would be to make room for a supercharger.......Now that i want someone to do so i can copy them

[Gwagensteve]

At which point the balance pipe would become redundant in any case- the cylinders will be being filled by positive pressure.

Steve.

[joeblow]

Geez....this thread has turned into a shit fight.

The 0.P probably has a point in the modification he did, but his response may have been a little too emotional. But then again Gwagen does have a habbit of shooting down modifications he has not personaly tried, thats just the Gman.

Suzuki are one of the only manufacturers to have a plenum that joins in the way it does. While the Gman posted pics of the 2.5 and 2.7 manifold he failed to post a pic of the update 2.7 manifold.......see below.



This has a butterfly that does shut off the balance pipe to give more performance, much more than my pre update XL does.

Whether shutting it off all the time is a good thing I'm nnot sure, but I must thank Gman for tipically shooting someone down that may have a good point. Hence why many people don't bother posting ideas on sites such as this anymore.

[Gwagensteve]

I think you've missed the point Joe, but I'm sure you won't answer my question... that's just joeblow.

When does the butterfly open up the balance pipe?

If people are insecure that their idea won't bear scrutiny then they shouldn't post it on a forum.

I learnt nothing from reading the OP's post, but through questioning it, we're all learning something.

If you can explain when the factory manifold opens and shuts the balance pipe, we'll know how close to the mark the OP was.

Steve.

[Rhinoman]

dhula wrote:

If this is the case then perhaps what is happening is that each bank does in fact haveenough of a plenum to suit the size of the "engine" it is feeding which will be aprox 1 litre each and the exhaust, should it be joined, is assisting in scavanging the gasses away allowing for a more complete A/F load being fed into each sylinder.
If this is the case then perhaps the ECU is not trimming fuel but in fact leaving things as they are but better performance/economy is being achieved by better efficency in the combustion chanber.

The ECU won't know that anything has been changed and in any case runs seperate trims for each bank.