Road going ITB setup

[DGJ]

is there a magic kit for this or directions, or is it all DIY?  (installing the Honda engine in a 2002)

And we have an Austin-Healey 3000 that we put a Toyota transmission into, using a kit, many years ago.  And it just occurred to me recently:  if there's no body modifications, why not replace the pushrod 2912 cc six with a 136 hp, with a DOHC  Toyota engine with 50 to 100 hp more?  Another deeply philosophical question.  Doug

[SteadFast]

17 hours ago, chargin said:

 

Just to kick the Hornets Nest, a S2000 F20c full swap kit is $4000-$5500 for 240hp at easy stock installation ?

 

 

 

You make an excellent point.  I've been so focused on an ITB swap, I've lost sight of cost.  I've always wanted to do a K20/24 swap...  That would likely cost less as the motors go for far less than F20/22's.  

[Healey3000]

12 hours ago, DGJ said:

is there a magic kit for this or directions, or is it all DIY?  (installing the Honda engine in a 2002)

And we have an Austin-Healey 3000 that we put a Toyota transmission into, using a kit, many years ago.  And it just occurred to me recently:  if there's no body modifications, why not replace the pushrod 2912 cc six with a 136 hp, with a DOHC  Toyota engine with 50 to 100 hp more?  Another deeply philosophical question.  Doug

Doug, are you referring to the Smitty 5-speed kit?

 

Naw, have to keep the lump of cast iron 2912 - that exhaust note!  I remember pulling it along with the gearbox and it nearly tipped over the engine hoist, one that was borrowed from a neighbor's big rig shop. ?

[pato2002]

The professional ITB's (TWM, Jenvey, etc) are very nice but pricey. Why not sidedraft manifolds, an adapter plate and some motorcycle throttle bodies? GSXR750 or Triumph 955's would be a good fit.

Some good reading over on Pelican:

http://forums.pelicanparts.com/porsche-911-technical-forum/932541-triumph-itb-aem-infinity-project.html

 

A quick mockup:

 

 

Triumph on weber manifold.jfif

Edited February 11, 2020 by pato2002

[Dudeland]

23 hours ago, chargin said:

 

Just to kick the Hornets Nest, a S2000 F20c full swap kit is $4000-$5500 for 240hp at easy stock installation ?

 

 

By the time my turbo dies, I will be going electric. 

[chargin]

 

1 hour ago, Dudeland said:

By the time my turbo dies, I will be going electric. 

 

I have had much turbo experience, factory OEM turbo's can be robust, once you start pushing harder lifespans can be shorter.

 

I've gotten as low as 10k miles out of a GTRS turbo with roller bearings due to a manifold bolt loosening, Not hatin wishing you the best on your build     

 

Just for reference:

Edited February 11, 2020 by chargin

[AustrianVespaGuy]

FWIW, I've heard though cannot personally corroborate that the Jenvey stuff is rather marginal Chinese quality, but the TWM / now Borla throttle bodies are a step up quality wise in comparison.

[69Bimmer02]

I'm fairly certain Jenvey manufacture only in the UK.  Unless they are false advertising on their website. 

 

"Jenvey Dynamics design, develop and manufacture all significant throttle body and induction system components in our single UK manufacturing site. This enables the close control of quality, research and confidentiality, essential in all forms of motorsport."

 

I'm having good luck with my ITB's so far, but they are still young.

 

 

[Healey3000]

On 1/31/2020 at 12:32 PM, jimk said:

Something for the ITB map sensing world.  A signal from a combined tube or can setup still will not produce a signal that correctly represents the runner pressure at the end of the intake stroke because the other runners are all at pressures greater.

This a a multi map board that reports the lowest pressure to the ECU.  The lowest pressure is what the ECU needs to correctly compute the air mass.  Other systems kluge the air mass computation

https://github.com/jharvey/MultiMAP

(Need some talent to produce the boards.)

 

That's an interesting approach.  Could one also tap a single runner and use a peak and hold so it is not subject to pulsatility?

 

However, with either approach, how does one deal with the vacuum signal to the fuel pressure regulator?  Idle control would also significantly affect MAP readings.

[jimk]

42 minutes ago, Healey3000 said:

That's an interesting approach.  Could one also tap a single runner and use a peak and hold so it is not subject to pulsatility?

 

However, with either approach, how does one deal with the vacuum signal to the fuel pressure regulator?  Idle control would also significantly affect MAP readings.

The peak and hold would need a quick release from the hold to follow the load.  Also I am wondering about the map sensor durability on the mulitmap board because they would be pulsing at a rate of half the rpm on light loads.  The greater the load, the pulsing value would decrease.

The fuel pressure regulator map reference would not work too well.  Would have to tune with a constant differential.

Idle control does not affect the readings.  The manifold runner pressure at the end of the intake stroke is the same no matter what type of manifold is used.  Air mass consumed per intake at a given load is the same no matter what manifold.

I prepared a paper for a guy explaining why the manifolded sensing tubes and buffer tank doesn't provide the correct manifold pressure either, but I don't want to go through that here.  Air moves back and forth between cylinders in the sensing tubes because the runner pressure in the adjacent runner is different.

[Dudeland]

Sorry I repeated myself.  God I need sleep

 

 

 

Edited February 13, 2020 by Dudeland
Sleep

[AustrianVespaGuy]

15 hours ago, Healey3000 said:

That's an interesting approach.  Could one also tap a single runner and use a peak and hold so it is not subject to pulsatility?

 

However, with either approach, how does one deal with the vacuum signal to the fuel pressure regulator?  Idle control would also significantly affect MAP readings.

I think the simplest approach to take for this is to tie the vacuum signal from all 4 runners together and then *maybe* add a small amount of additional volume to help smooth out the signal pulses if needed, though I suspect there might already be enough volume in the FPR and tubing itself that this probably isn't all that necessary.  The goal is to have enough volume to minimize any spikes in the pulses while not having so much volume that it starts to create a lag in the signal.  That said, @jimk is of course correct that all this 'averaging' will always give you a bit higher reading that what the actual cylinders see, so your VE table would need to be tweak accordingly to compensate.  I bet that's why many of the engine management systems offer an ITB mode that is essentially a hybrid of both Alpha-N and speed-density fueling calculations.

[Healey3000]

Jim and AVG,

 

With all these compromises related to MAP and FPR, etc., it makes you wonder whether ITB's are worth it for us hobbyists.  We may end up with reduced performance as compared to a well designed common plenum with a single throttle.

 

OEM's with their resources can optimize ITB's and engine management.  A dyno head to head with a set of Jenvey ITB's and the e30 intake would be very interesting.  I'll poke around on their website to see if they have this.

[jimk]

2 hours ago, AustrianVespaGuy said:

The goal is to have enough volume to minimize any spikes in the pulses while not having so much volume that it starts to create a lag in the signal.  That said, @jimk is of course correct that all this 'averaging' will always give you a bit higher reading that what the actual cylinders see, so your VE table would need to be tweak accordingly to compensate.

Yes the volume is needed but it has to deliver air from the volume chamber to the runner FAST. Sensing tubes are not big enough, need a minimum of 3/8" id tube.

The higher pressure will work but the tuning will all be in the 70-100 kpa range in the table.  The lower pressure cells are wasted.

BTW forget using the term VACUUM with EFI, It air pressure!  The pressures just happen to be sub-atmospheric.  Vacuum is for the old school carbbies.

[jimk]

2 hours ago, Healey3000 said:

We may end up with reduced performance as compared to a well designed common plenum with a single throttle.

I did performance tests on a M10 a few years ago and posted the results with curves on the FAQ.  The only difference in power based on fuel rates and the same AFR is with the ITBs above 5800 rpm.  So unless that's your speed range, ITBs look cool, sound cool, drive you nuts on long drives and performance is not compromised.  My favorite is the E21 intake manifold.  It ain't that hard to setup.