Fuel Injected ITB's

[vwjunkie42]

Because lots of people struggle to make it work.

listen to this guy he knows what hes talking about. he helped me quite a bit..... hi paul

[Sycoticmynd29]

listen to this guy he knows what hes talking about. he helped me quite a bit..... hi paul

Oh I know, I felt special just because he actually responded in the thread to begin with haha.

So far every time I've seen his name he has been dishing out the knowledge

[weeblebiker]

Because lots of people struggle to make it work.

I'm still struggling to make it work.

[xr4tic]

Here's the start of my build thread from 5 years ago:
http://forums.vwvortex.com/showthrea...n-(lotta-pics)

I've done a bit more to it since I last posted, here's the new ITB manifold, it points the ITBs right into the grill as opposed to the hood like most are setup.



I'm still working on the tuning, once warmed up, it runs great, getting it warmed up is the problem.

[Sycoticmynd29]

I've been trying to think of how I would like to mount my ITB's if I want to do something like you have and point them directly at the grill, or if I want to do the normal set up.


My main issue is I have read that the length of the runners is very important to the power output of ITB's and that the distance from the throttle to the valves should be controlled and within a certain range to be really effective.

It could just be the angle of the pictures, but to me your runners look longer than most of the other ones I have seen, and right now I am unsure of exactly how long I would want my runners to be.


Thanks for the link, I should have some free time today to browse through the last few links you guys have posted.


Link to the article talking about runner length

That's the FAQ section on the Jenvey site, they have some information about picking throttle diameter as well as deciding on a runner length.

I haven't tried to figure out what the best length would be, mostly because I want to wait so I can measure everything out myself.

[xr4tic]

Good catch on the runner length, I completely forgot about that point.

I had done some calculations and came up with a runner length, but I forget what RPM range I had designed it around and what length numbers I came up with.

I do remember it was MUCH better than just slapping ITBs on and pointing them straight up. Short runners are good for high RPM power, but doing it that way is too short.

My runners are ~9" long from the face of the head to the start of the TB, my original manifold was only 4". Overall length from trumpet to valve ~17" vs ~12"

Plug those numbers into this calculator, and you'll see the difference: http://www.bgsoflex.com/intakeln.html

[Sycoticmynd29]

Good catch on the runner length, I completely forgot about that point.

I had done some calculations and came up with a runner length, but I forget what RPM range I had designed it around and what length numbers I came up with.

I do remember it was MUCH better than just slapping ITBs on and pointing them straight up. Short runners are good for high RPM power, but doing it that way is too short.

My runners are ~9" long from the face of the head to the start of the TB, my original manifold was only 4". Overall length from trumpet to valve ~17" vs ~12"

Plug those numbers into this calculator, and you'll see the difference: http://www.bgsoflex.com/intakeln.html

I feel like the throttle diameter would also play a pretty big part in that effect, but that calculator doesn't account for the diameter used to calculate those values.

Unless I'm wrong and the diameter doesn't play a part (which is likely)

[need_a_VR6]

The throat diameter has nothing to do with the resonance frequencies, only in determining the velocity, which matters more once it's "wet" then dry.

[weeblebiker]

yup diameter doesn't have much to do with harmonics in fluid dynamics. the density of the fluid impacts the harmonic frequency more.

[ButtedorFrank]

some usefull information on this thread, I am reading and reading and reading, cause I also want to build a 16v itb ... I wanna build it right without cutting any corners. the plan would be basically to have a good, reliable, peppy engin that I could drive in the summers, go to shows and track and such.its gonna be going into a 4 door mk1 jetta.

I read that the power you put out has alot to do with the amount of head work you put in.
does anyone know the difference between the .5mm oversize valves and the 2mm oversize ? I would think better air flow would allow you to put out more power. Could it be too much for an NA engin ?

I wanna put 288 cams, oversized valves, high compression piston, new bearings, arp bolts, ect.

the engin I am looking at picking up is out of a b3 passat (9a).
My question is :why would someone want to take an ABA bottom end instead of a 9a ? from what I had read I thought you could get more out of the 9a bottom end ?

and I read i'd have to balance the crankshaft, but what is the difference between Autotech 2.1 crank (= OEM TDI crank ?) and the crank in the 9a block ? does the autotech (or tdi) cranks already balanced ?

sorry for the noob questions, I'm just trying to make sure I understand everything and that I don't miss an important step to make a good motor that will last me a while.

very usefull thread, keep us updated on your build

[JakRabit]

I run almost the exact setup you are talking about but in a mk1 jetta coupe in las vegas. The bottom end is aba though and it runs on e85(ethanol)

[weeblebiker]

im running turbo itbs on e85 megasquirt
just got an aba bottom the main thing is the crank position sensor.

[Sycoticmynd29]

So I asked about ignition timing a bit ago, and was given some helpful links.

But now I have another ignition related question;

So far I have seen people talking about how they are going to control their ignition timing, Map sensor, or alpha-n.

Alpha-N Explained
That is the only explanation I have read so far about Alpha-N, but as far as I know, its a pretty solid basic description.

I have no problems using an aftermarket ignition computer, and I would actually like to head in that direction.

It seems like people prefer Alpha over MAP as the vacuum advance can be somewhat unreliable?

Generally, what are the main pro's and con's of each?
Which will be easier and more dependable in the long run?
What are the biggest complications of either?


Thanks guys!

[vwjunkie42]

I would also like an answer tonthat question. As I am running Alfa-n for fuel and speed density for spark and feel like its not meshing well.

[Sycoticmynd29]

Also, I just revisited the lugtronic site and saw that it has 8 ignition outputs, does that mean I could use that as the ignition computer as well?

Also, when I talk about ignition computers I mean things like MSD or Megajolt.

[bonesaw]

you will find with an ITB car the car runs too differently from 92 kpa to 94 kpa to 96 kpa where on a regular NA car it does not vary to much. To remedy this you will use alpha-N. I can tell you at the track we were originally using the MAP sensor and the car went slow because of the MAP sensor and made adjustments and next run picked up 3 seconds.

[need_a_VR6]

The smaller the throttles the less effect like that you get, but there is no way around it. If your car idles ~50kpa you might have a shot as long as you dont want different afr targets in that range. On this kind of tune getting it close and using full time o2 correction is your friend.

[vwjunkie42]

question for you paul.
i dont want to thread jack but thought the info would be good to add here

i am having trouble tuning my cruising area. when i am cruising at partial throttle and give it a bit more, like to get up a hill, my afr goes lean. i am running alpha-n for fuel. and ign-load or map for ignition. i think whats happening is. that as map goes up timing is advancing and demanding more fuel from the same cells that are fine at lower kph. is there a work around for this. should switch my ignition to alpha-n as well, if so what should my table look like? should i smooth out my ign table so that advance stays constant in an rpm range. i have ego correction on. i may have it set to mild.
i have posted below screen shots of my ign table and ve table.

[Sycoticmynd29]

I can't make up my mind on the specifics of this! I keep making small changes to what I want over all.

I am currently waiting to hear from a friend, who is waiting to hear from a friend, about getting a couple of 16v swapped ABA's, so I should be starting some of this build soon. Hopefully.

So far, here is the new plan:


OBDI ABA bottom end with all new seals, gaskets, bearings

ARP bolts / studs on everything

12:1 pistons (I have not looked into this at all, probably unrealistic on pump gas)

Lighter forged rods

Jenvey ITB's (their 16v direct to head kit is now $900, comes with the fuel rail and linkages)

276*cams

Solid lifters (not sure about these, no point in building a head to go to 9k RPM if I can only get to ~8k)

rebuilt valve train, lighter weight, heavy duty parts

Big Valves (was originally against this as I was trying to keep the 16v head close to stock so if I chose to boost I wouldn't have effected anything)

Multi-angle valve job

port and polish (probably relatively mild)

Water Meth, set to kick in at higher RPMS (almost no research for this either, so I'm not sure what would be most effective.)

With Lugtronic standalone.

[bonesaw]

I can't make up my mind on the specifics of this! I keep making small changes to what I want over all.

I am currently waiting to hear from a friend, who is waiting to hear from a friend, about getting a couple of 16v swapped ABA's, so I should be starting some of this build soon. Hopefully.

So far, here is the new plan:


OBDI ABA bottom end with all new seals, gaskets, bearings

ARP bolts / studs on everything

12:1 pistons (I have not looked into this at all, probably unrealistic on pump gas)

Should be fine with standalone. Ill let you know after my 93 tune. Been running E85

Lighter forged rods

Jenvey ITB's (their 16v direct to head kit is now $900, comes with the fuel rail and linkages)

276*cams

Solid lifters (not sure about these, no point in building a head to go to 9k RPM if I can only get to ~8k)

I wouldnt bother. Hydraulic can rev pretty high.

rebuilt valve train, lighter weight, heavy duty parts

Big Valves (was originally against this as I was trying to keep the 16v head close to stock so if I chose to boost I wouldn't have effected anything)

Multi-angle valve job

port and polish (probably relatively mild)

Water Meth, set to kick in at higher RPMS (almost no research for this either, so I'm not sure what would be most effective.)

Wouldnt bother. Wont have the cylinder temps like a turbo car will

With Lugtronic standalone.

[Sycoticmynd29]

The meth was more because of the high compression on 93 octane, as I said, I haven't looked into compression that high so I am unsure of how safe it is to run regularly, so I threw the meth in as a safety net.

[need_a_VR6]

The 20/20 I tuned ran great at 12:1 on 93 at 32deg total timing (dyno tuned).

[Sycoticmynd29]

These blocks have oiling issues at really high rpm, we've blown up a few of them so I know what of I speak. If you plan to turn them much over 8000 rpm get oversized bearings that increase the main and rod clearance by 0.001". This is one of our 8v grenades, it happened when coming off throttle at about 8700 rpm.

Has anyone else done or heard of the oversized bearings being used?

Even worth looking into if I plan on limiting my revs at 8k?

Are there any improvements I can make to the oiling system? A better OEM pump or anything?

[bonesaw]

We use stock bearings and stock oil pumps. Revving motors to 9k with no issues

[simon-says]

That pile of parts looks to me like a rod bolt failure. The head is missing off of one bolt. There can be many reasons why it happened, but to me. 8700rpms to low rpms at full vacuum = rod bolt stretch.

[Sycoticmynd29]

That pile of parts looks to me like a rod bolt failure. The head is missing off of one bolt. There can be many reasons why it happened, but to me. 8700rpms to low rpms at full vacuum = rod bolt stretch.

Would ARP hardware resolve this possibility?

We use stock bearings and stock oil pumps. Revving motors to 9k with no issues

Are there any upgrade options for the pump?

any difference between the ABA and the 16v pumps?

[Prof315]

Would ARP hardware resolve this possibility?




Are there any upgrade options for the pump?

any difference between the ABA and the 16v pumps?

ARP hardware (especially rod bolts and head bolts/studs) is ALWAYS a good idea on a high revving motor.

The safest way to build a high revving (over 8000 rpm) VW 4 cylinder water cooled engine is to use a dry sump. For drag racing or street use where you aren't hanging the motor at 9000 for a couple of minutes you _should_ be ok with a stock oil pump. BUT, if something goes wrong thing will come apart in a hurry and you can probably write off the tranny as well as the engine.

ABA and 16V oil pumps have different ends on the drive shaft. You can however retrofit a 16V oil pump into an ABA if you grab a 2.0L 16V oil pump drive and plug.

[Sycoticmynd29]

ARP hardware (especially rod bolts and head bolts/studs) is ALWAYS a good idea on a high revving motor.

The safest way to build a high revving (over 8000 rpm) VW 4 cylinder water cooled engine is to use a dry sump. For drag racing or street use where you aren't hanging the motor at 9000 for a couple of minutes you _should_ be ok with a stock oil pump. BUT, if something goes wrong thing will come apart in a hurry and you can probably write off the tranny as well as the engine.

ABA and 16V oil pumps have different ends on the drive shaft. You can however retrofit a 16V oil pump into an ABA if you grab a 2.0L 16V oil pump drive and plug.

The reason I asked about the difference in pumps is because the two ways the 16v head swap can be done. One way using the 16v pump and IM shaft, and the other way, using the BBM Dizzy Gizzy and retaining the ABA pump.


I am leaning more towards retaining the ABA pump, just so there is a bit less mix and matching.

[ABA Scirocco]

I am leaning more towards retaining the ABA pump, just so there is a bit less mix and matching.

I'd be leaning the other way stock 16v parts are cheaper, at least as good and a fair bit easier to use. Using the dizzy gizzy also requires you to get the BBM intermediate shaft sprocket as the normal 16v sprocket doesn't fit the ABA intermediate shaft so you'll be sending at least $240 to BBM just to drive the oil pump when there are perfectly suitable stock parts that can be had for a fraction of that especially if you've got parts from the engine that donated your 16v head.

[Sycoticmynd29]

So last night I made the first big move towards getting this started.

Paid for most of this:

EXTRAS:
1x OBD1 ABA (complete)
1x OBD1 16v/ABA disassembled:
Ported 16v head w/ Ti retainers/HD springs
Eurospec main bearings (New in box)
OE rod bearings (NIB)
ARP main studs (NIB)
ARP rod bolts (NIB)
ARP head studs (NIB)
AWIC intercooler
AMS 16V manifold
Eurosport underdrive pulley clearanced for 16v/ABA



As part of a group buy a friend and I are doing. Also getting a set of GSXR ITB's with the deal too.

Now I just need to get it from 10 hours away :[

[bonesaw]

This is now turbo AND Itbs?

[Sycoticmynd29]

This is now turbo AND Itbs?

No, but the 16v ABA was originally being built for boost.

It is part of a much larger deal, a friend of a friend (seller) is moving, so he is trying to get everything out of his house before he leaves.

My friend was interested in it because he is getting a monty green gti thats wired for a VR swap, a VR, a whole bunch of other parts, then the stuff I posted.

I wanted the ABA stuff, so we set up a group thing where I buy this stuff, he gets the shell and VR, and other people we know are getting other odds and ends.


However, I think once I get the 16v in my car, I'm going to start building another motor for boost.

[SirSpectre]

for turbo'd ITBs. Those things sound amazing. on having to build the plenum for them

[Sycoticmynd29]

for turbo'd ITBs. Those things sound amazing. on having to build the plenum for them

Maybe one day, but for now, I'm all N/A.


Jenvey sells plenums I think btw

[vwjunkie42]

Idont think the jenvey plenums are made to hold boost.