ITB's

[brad91 0]

Hey guys.

Been a while since ive been on here as i picked myself up a new drift car and didnt need 3 but ive decided i want to keep building this.

Found a guy here in aus who has a set of rb26 ITB's with a custom manifold to suit m20 for $350!!!

What would i need to run these? Is there any way i could run them off a factory ecu and what extra power could i see from them? Partially want to run them just so i can have ITB's and be different from all the other p platers around here with a milo tin exhaust and pod filter lol.

How much work is involved in running ITB's? Can i tee all the vacuum lines together and run to one point? and what do i do with the AFM?:S That part really has me confused.

I love the sound of ITB's but if i had to could i run an air box around them and put the AFM at the inlet to the air box? Would lose the ITB sound but still retain the power gain wouldnt i?

Cheers

Brad

[thorburn 121]

Your more than likely to loose power on a standard m20b20 engine. Without cams with a bit more lump, good headers, and possibly some head porting your not going to achieve much apart from an engine that is very hard to tune

You can do as you've said and attach a vacuum from behind the throttles. If it feeds into a chamber you will get a more consistant vacuum signal (if you use a map sensor you'd probably want this).

You could also use your afm and standard ecu but you'll still have a very hard time tuning it.

It's a lot of effort for a bit of wank factor

I'll buy them if you don't want them though

[brad91 0]

Well for $500 i get a m20b23 engine which i was planning on using the cam out of, i get a b25 remapped ecu from a drift car that was dismantled for a 1j (dont know if that would work with my b20), the manifold to suit, the rb26 ITB's, and anything else he can find laying around to suit e30.

Would it be overly hard to set up? Im planning on a 2.7 stroker build one day aswell when i can find the parts cheap enough. Sourced a 2.7 block for $700 and just going to put my head on it.

But yea is it worth it? I really want to do it as it would be awesomly unique for someone my age to be driving around here and i really want the power so i can drift it.

[thorburn 121]

The hardest part will be the tune. You could slap it all together but it's going to run like rubbish if it even runs at all.

Which injectors is it using?

You sound like your all ready convinced on buying them. Worst comes to worst just sell them off

[brad91 0]

Its a dead stock motor currently. I can organise injectors and other stuff as i go along. I already have a decent seat of headers and exhaust system to go with it.

What sort of injectors should i run? How do you go about tuning the stock ecu? Can it be done? And what do you need to tune? obviously air/fuel mix but do you tune it through the ecu or by adjusting the TB's or a bit of both? Really dont know a lot about it but ive seen them on a beema before and they sound amazing AND give it a fair bit more power lol.

[barf 0]

the old Motronic ECU won't like the ITB's much! tuning ITBs is complicated, the older speed-density algorithm used by the original ECU may not permit you to go far, and you'd still be stuck with an AFM anyway. blended table, called Hybrid-N (Alpha-N multiplied by Speed-density table) as found in Megasquirt 2 (MS2/Extra) is designed for ITBs and MS2 kicks ass in general. www.diyautotune.com

theres a list of injectors and flow rates here: http://users.erols.com/srweiss/tableifc.htm

formulae for injector selection here: http://www.rceng.com/technical.aspx#WORKSHEET

for tuning, you'll want a wideband Oxygen sensor (they actually measure Nitrogen but, I digress). I've had good luck with Innovate LC1, they're about USD$200

[brad91 0]

so is a wideband oxygen sensor something that stays in the car or just gets used for tuning?

Also what is a megasquirt worth and how hard are they to install? Ive read a couple videos saying they plug straight into your current loom if running motronic? And moreso where can i get one? lol. I cant find them anywhere on ebay or here in aus.

Being rb26 ITB's i got told i could run the origional chamber instead of trumpets and run my AFM off the front of the plenum chamber? (it doesnt come with the plenum but was thinking i could tig something up at work here) until i can afford a MS2 and then i can go to open trumpets one day later on?

Would the old jetronic ignition be worse to run ITB's on or better? As for $500 i get the m20b23 motor, loom & ecu aswell for any parts etc i need

[brad91 0]

would this plug and play setup work?

http://www.diyautotune.com/catalog/diypnp-...4b6ee0b10866ff1

Or would i need to go to the megasquirt complete? such as the ones in the following link

http://www.diyautotune.com/catalog/megasqu...4b6ee0b10866ff1

If someone could link back the exact one i would need that would be amazing. Computer systems are not my strong point haha.

Basicly i want to get it so it will run with the ITB's then worry about ecu and massive power later on if possible. Or buy the ITB's and get everything so i can do it all in one hit although i dont want to spend months before i can drive my car lol.

[Jacko 2156]

Sounds like a path too a headache man.

individual throttle bodies arent gonna do naff all for power, it'll look and sound cool with trumpets. Your better off saving the thousands you will spend getting the RB26 throttles to work on something that will actually return some gains.

Itll cost a bomb, will be a nightmare too setup, and without going for a nuts NA tune wont do jack shed when it comes to output.

[brad91 0]

im stuck with an NA motor for another 12 months and want something off tap to drive around in for that time as im sick of driving my tow ute everywhere as i cant drive the fc lol.

So there is no way i can cheaply set them up? The ITB's with the 323 motor and m20 custom manifold is only costing me $500. If i can get out of it under $1000 or $1500 at worst thats fine. I really really want that sound and plan to make some pretty nuts power out of it.

Is there anywhere i can find a step by step guide to running ITB's? Was thinking about just getting it so it runs now for the sound and over the next couple months getting the ecu, tuning it up and making some decent power.

[APT 195]

Sell me the ITB's !!!!

[brad91 0]

lol i know they are uber cheap which is half the reason i want them lol. That and ITB's are awesome.

So what will i need to make these run with the standard ecu? Even if it doesnt give me a power gain.

Just read that you can get a TPS/rpm thingy that converts a signal and you hook it into the afm meter to make it run?? confused me a bit but i think i got it. No idea how it works though lol.

on a swift using standard ecu with custom plenum over ITB's

http://members.iinet.net.au/~rospen/projects/quadgti.asp

^^Could that work?^^

Here is another custom plenum with better photos once again going on a swift

http://www.redlinegti.com/forum/viewtopic....f=7&t=18276

Could a plenum like that work, bolt the afm to the plenum inlet and away i go?? or not that simple? lol

[Mike 1]

^ That sort of setup would have it running, but it wont do much for performance.

Few other thing's need to be fitted like TPS, warm up and idle control etc but in principle it should run

Edited November 9, 2010 by Mike

[pureboiracer 0]

^idle is for girls...

imo just shell out the $$$ for a good computer, like a link. that way it will cost you quite abit more but you can keep that computer and put it behind any motor you decide to build.

as for the itb,s buy them throw it on and see what you want to do in terms of tuning, if all goes pair shaped you could sell them on trademe easily enough and probably cover nearly all of ur costs

[brad91 0]

ok so i think im gona shell out the cash for these soon. When i build the airbox does it have to be any special shape or anything like that? or can i just fabricate a square box with an opening in one end?

[thorburn 121]

Because this is purely for noise and making the car run worse. You might as well just use a square box. My vote is a heineken box soaked in epoxy.

Personally i'd like to know if your car will run at all.

Good luck

[brad91 0]

haha no way id so use a XXXX box!

It is for performance. I may leave the ITB's off for the moment and start building myself a complete motor to drop in with it. Something like the 2.7 stroker motor then once thats built up drop the whole lot in at once. My plan is to make someone around 200hp or more hopefully at the wheels. I just wanted it so it runs for now and i will play with it as i go.

If i change the ecu and ITB's at the same time i will have endless trouble figuring out whats wrong etc. If i can make it run with ITB's and the factory ecu then change things as i go atleast i can troubleshoot a lot easier right?

And the main reason for going ITB's first and not ecu first is $300 for ITB's WITH the manifold to suit a m20 motor is stupid cheap imo.

So yea, what shape should i look at making the plenum? I have a sheet of 1.5mm alloy to work with is the other problem. Would be crazy hard to bend it and do crazy curves etc.

[thorburn 121]

It is for performance.

More likely then not, your going to loose performance. Change the ecu first

I may leave the ITB's off for the moment and start building myself a complete motor to drop in with it. Something like the 2.7 stroker motor then once thats built up drop the whole lot in at once.

So your going to risk destroying a new motor?(destroy is probably an exaggeration) Change the ecu first

If i change the ecu and ITB's at the same time i will have endless trouble figuring out whats wrong etc. If i can make it run with ITB's and the factory ecu then change things as i go atleast i can troubleshoot a lot easier right?

This could just be my opinion but your doing this wrong

But please do prove me wrong though.

I'm just an internet jockey and have minimal real world experience. My opinions are large and a lot of the time meaningless

[Gaz 1061]

Hey Brad,

Have a read through this thread here to see what MLM is doing to get his ITB's done and running properly. And he isn't expect any performance gains yet look at all the trouble he is going to as he doesn't want to ruin his engine.

http://www.bimmersport.co.nz/forums/index....showtopic=28044

One of the most important parts on a car is the ECU and if you make any performance mod's you will want to update the ECU to match the mods and to get the most out of them. As send before, it won't run on your standard ECU so go aftermarker first, then the ITB.

Do it once, do it properly.

Edited November 11, 2010 by Gaz

[brad91 0]

More likely then not, your going to loose performance. Change the ecu first

So your going to risk destroying a new motor?(destroy is probably an exaggeration) Change the ecu first

This could just be my opinion but your doing this wrong

But please do prove me wrong though.

I'm just an internet jockey and have minimal real world experience. My opinions are large and a lot of the time meaningless

Sorry man i wasnt have a go at you or anything. I honestly can see where you are coming from. But from what i have read every other ITB setup for beemas are like $3000. I thought $300 was dirt cheap which is why i wanted them. Even if i wasnt to run them currently.

Would i be better off just going to a larger throttle body? I can get those off ebay for like $120 or something like that

[Jacko 2156]

Its only gonna suck as much air as it can suck. Putting a "bigger hole/larger throttle body" in one end isnt gonna make it suck any more air, its the equivalent of bolting a 4" exhaust to a stock M20, itll be worse, not better.

Your going about it ass about face sorry man. Make your engine thirstier, then stick stuff on it too feed the thirst

Edited November 11, 2010 by Jacko

[brad91 0]

how do i make it thirstier? lol. The head will be getting a full port and polish when the work is done? My mates an engine reconditioner so ive conned him into doing it for me lol. If ITB's go on the head will be done before they go on.

Other than that im not sure what i should do. Without pulling the engine out of the car (head off is fine) what mods should i do for cheap to give me the most power? I really like the idea of ITB's even if they sit there a while and i get a few other parts to go with it.

But yea the head will be done, i will get a bigger coil pack, better plugs/new plugs, better leads at the same time as the ITB's go on. Just not the ecu as i dont have $1000 for an ecu :S unless the plug and play ones are cheaper than that?

[AN E30 Fan 1]

Honestly mate,

Listen to what everyone is saying,

IMO Do the 2.7L conversion and leave it at that, 2.7L make quite a fair bit of torque over the standard B25. Your going to spend $300 getting the ITBs and yes you MAY have it running but its not going to like it. As Gaz said do it once and do it right. Don't do an half ass attempt because in the end you will end up spending more money correcting it.

Sorry if it seemed harsh but your talking about wanting more power when all its going to do is decrease it, if you don't to it properly.

[brad91 0]

yea fair enough guys. Might buy them and keep them for a rainy day lol. Then i can get the ecu at the same time and get it all running properly.

Wil my b20 head work on a stroker motor? As i will get that ported for the moment and that should be fine to run with the stock ecu shouldnt it? And what cam would you suggest running? Ive heard the b23 cam works? Although b23 is from the older motor and mine is a 89 facelift model so would it still work?

Then ill look into getting the 2.7 block and giving it a freshen up and dropping my head on. That sound like a better idea?

OR should i, do the head, buy an ecu, fit ITB's and run a b20 with ITB's? Which would make more power/usable power/response/cheaper?

[brad91 0]

Will this megasquirt system work? With the way the AUS dollar is to the USD currently id snap one of these up in an instant if i could lol. Could this system run the car fine? And what function would the ecu need to run 6 seperate coils at a later date? I see it says it has 4 coil on plug sparks or 8 wasted spark. Dont know what it means by wasted spark though