intake design Q

[ozconnection]

You bet it does!!! Great to see someone else moving in this direction.

 

Tell me about your throttle body, injectors, intercooling, management, turbo, compression, cam, head and bottom end configuration, Oh heck, tell me EVERYTHING...please!

 

Looks awesome mate.

 

Cheers.

 

Ps. Xnke was very patient with me and I have the car running well based on his advice. There is certainly more work to do with megasquirt, getting it to run factory smooth but I just ran a round trip to Phillip Is. from Sydney (2500 kms) which included some track time and I was very happy with it.

 

Heat shielding is very important, my fuel was getting hot and the tune was changing on longer drives. It's better now.

Edited July 13, 2013 by ozconnection

[SuperDan]

Right now it's just a stock L28E that is in real good shape. I am going to run it while I work out the tune etc and then build a new turbo motor I have sitting in my garage.

The turbo is just a cheap ebay one I have had for a few years that I use for mocking things up, still have not decided on the exact specs I plan to run.

After researching for months and adding up prices and comparing features etc I decided to take the easy way out on the throttle body and engine management and went with a Holley Terminator setup. Holley's engine management systems are VERY capable systems and for what you get the price is really hard to beat

.

I am still on the fence about running an intercooler. My original idea was to keep this setup simple and clean and just discharge from the turbo directly to the throttle body. We are a bit lucky here in San Diego and have 3 or 4 E85 stations and 1 of them happens to be 4 blocks from my house... I guess you can see were I am going with this

I have been wondering about heat issues and looks like you are confirming my concerns.

[TimZ]

I've done a lot of reading from the sites and I still see some big grey areas. The trouble is you dont know whats important and what isn't. You could read a sentence that could make a HUGE difference to the tune overall, but skip it because its included with other stuff that looks fairly irrelevant.

 

Injector dead time for instance....wtf is that??

 

Maybe I should have bolted all this stuff onto an old cluncker. I really don't want to wreck my lovely new engine whilst hit/miss with this new efi stuff. I had a map sample error and found buggar all information as to what it was or how to fix it. Now, it seems to have gone. My o2 reading on tunerstudio is still reading stupid reading, one second its 9 to one, then 22 to 1, and its sending autotune into circles....the engine runs like crap as you can imagine.

 

I'm not a MegaSquirt expert - I use a TEC3r instead, so I'm making some assumptions about nomenclature here.  BUT most injection systems have a setting for the minimum pulsewidth that you actually send to the injector - if your VE settings calculate less than this value, it uses the min pulsewidth value instead.  On the TEC they call this the Minimum Injector On-Time.  I'm going to venture a guess that the Injector Dead Time is your equivalent to this setting.  If I'm wrong then I'm sure that somebody here can point you to the correct equivalent setting.

 

If you have this setting programmed too low then you can send the injector a pulsewidth that is just too short and it stops functioning properly - there is a pulsewidth value below which the injector doesn't open at all, there is a value where it works reliably and then there is a range in between where it works, but unpredictably.  When you are in this range you'll see weird things like AFR of 9 one moment and then 22 a few moments later when nothing else has really changed, just because the injectors are dribbling fuel out erratically.  Sound familiar?

 

You might just try upping this setting until you stop seeing the 9 to 22 type jumps.  If your injectors are really big then you may find that the value that gives you stable readings might be a bit rich...

 

edit:  I am assuming that you are talking about behavior at idle or really low load, not under power where your pulsewidths should be sufficiently large to be out of this region.

Edited July 18, 2013 by TimZ

[ozconnection]

I put the coupe on the dyno (rolling road) and a friend of mine posted this vid on Youtube/Facebook for me.

 

Here's the link. http://youtu.be/4IpzjwGZbpA

 

Final figure was 106.7 rwkw (143 hp).

[SuperDan]

Finally got mine running. 

I had to ditch the turbo for now since I recently became un-employed and decided to just finish it with what I have.

I have running it now for about a month now and I am really pleased so far. It runs excellent. Driveability is exceptional and no more falling on it's face after about 5000 rpms, it just keeps pulling all the way to redline.

There was some concern about running such a large throttle body (1000cfm) on a single plane intake and how it would effect low speed / off idle. There is no problem, it is really responsive.

For ignition I ended up just using my 77 280Z distributor. I locked out the mechanical and vacuum advance and wired it up to an 8 pin HEI module. Works perfect with the Holley setup. 

Once I get some income going again I will be turboing this sucker for sure

[ozconnection]

Excellent news!!!

 

I have some updates myself and will post them up later today. (At work ATM)

 

[ozconnection]

Love what's happening there Super Dan. 

 

I recently did some work on the dyno and netted 111 rwkw with a mapping and a tweak to the cam timing.

The operator of the dyno suggested a few things to try, my setup needs better injectors, the Seimens don't atomise finely enough, the mapping needs to be done with an N-Alpha (tps) and the phenolic insulator needs to be ditched. A heated throttle body would dramatically help with fuel mixing with the air in the vicinity of the TB. My injectors are outboard of the throttle, so atomisation here is VERY important. He also removed the vacuum line to my Malpassi regulator because of the erratic mapping on the VE map it was causing. Tuning the fuel curve seemed much easier after this little mod.

Very happy with it overall, works really well on the track

 

 

 

Edited December 19, 2013 by ozconnection

[Tony D]

This is old school, but some manufacturers had honeycomb under the carb to help atomise the fuel, an old-timer's trick (especially in the days of cold starting  globules of fuel burping out of Q-Jets was to sandwich a fine (100 mesh maybe) brass screen between two carb spacers. You got plenum separation, and the fuel droplets impinging on the screen broke it up further (at an admitted restriction of some sort...) I think the term in the day was 'homogenizer screen' or some such blather. Might be worth a shot...but I would think modern EFI components would atomize properly.

 

Then again.... most don't realize that most injectors fire against the opposite port wall, or backside of the intake valve/port wall to make a 'wet layer' which is where the tau layer theory comes into play in regards to responsive EMS.

 

A Throttle Body injector is quite a bit different in dispersion pattern than one that is designed for port injection. This may indeed be a root cause. You might try some of the bosch-pattern ford injectors (small o-ring top) or other TBI setups to get a  'wider fan' dispersion of the injected fuel, as opposed to the finer-shot of port injection.

 

Of course, if there was a screen below the throttle plates for that current port-injector to impinge upon and make a tau layer.....

 

Hmmmmmmmmm....

[Tony D]

Super Dan, what is your ems?

 

I must admit I'm a current member of the 4 barrel set myself...albiet with a little twist...Muahahahaha!

 

 

 

 

[ozconnection]

What the hell is that Tony? 

 

I know I haven't been around for a while but that thing looks like....FUN!!

 

Thanks for the advice on what style of injectors I might try, and the theory and practise on  'homogenizer screens'

 

Interesting idea!

Edited December 19, 2013 by ozconnection

[SuperDan]

Love what's happening there Super Dan.  

Thanks. I am still getting a few things sorted before I finish dressing up the wiring etc. I have no dyno numbers but my seat dyno says that I am not sure the car is really any "faster" but just pulls harder and runs better.

One thing I and some of my friends noticed was that the exhaust sounds... meaner, not sure why but it does LOL.

 

The operator of the dyno suggested a few things to try, my setup needs better injectors, the Seimens don't atomise finely enough, the mapping needs to be done with an N-Alpha (tps) and the phenolic insulator needs to be ditched. A heated throttle body would dramatically help with fuel mixing with the air in the vicinity of the TB. My injectors are outboard of the throttle, so atomisation here is VERY important.

One of my other concerns about this setup was the size of the injectors in the Terminator TBI, they are 85lbs injectors. I did some research and the new injectors they use have very fine resolution (I guess that is what you call it) and I have had no problems tuning it down to a 500 RPM idle.

I did use the manifold heater built into the Clifford intake. One of things that I think are helping with this setup is the throttle body uses what Holley calls an (annular discharge ring) to help with atomization.

 

 

 

Super Dan, what is your ems?

 fuel mixing with the air in the vicinity of the TB. My injectors are outboard of the throttle, so atomisation here is VERY important.

 

Holley EFI HP. http://www.holley.com/division/HolleyEFI.asp#96

I ended up buying the Terminator system as it included the throttle body, harness, all sensors a handheld programmer etc. It's really hard to beat what you get for the price. There seems to be some confusion on the interwebs that this system can only use the handheld programmer for tuning it, this is not true. It is an HP series ecu and you can plug in a laptop and tune it. 

The handheld programmer is pretty easy to use but I ended up just using a laptop so I could access all the features not available using the handheld. I velcroed it to my dash and use it display any sensor data I want to see, it works kinda nice for that.

 

I must admit I'm a current member of the 4 barrel set myself...albiet with a little twist...Muahahahaha!

 

That is really cool.

One of the things about the Terminator throttle body is that Holley does not offer 2 or 3 bar map sensors. They figure since it supports 600hp out of the box that using a blow through turbo or supercharger exceeds what a TBI can/should be used for on a V8 engine. I guess that is true, but for smaller engines such as an L6, getting to that 600hp is not very realistic.

The map sensor is a GM LS style sensor that plugs into the TBI. You can use a standard GM external style sensor by unplugging it, and changing the sensor connector. I did not want to do that and wanted to keep it plug and play so after some research I found 2 and 3.3 bar sensor that work.

 

GM MAP Sensors, true linear 0-5 volt scale

Delphi 2 bar - 12615136 (Various GM cars/trucks)

Delphi 3.3 bar - 12215049 (2004 SILVERADO 6.6L DIESEL) 

 

These sensors are slightly different than the stock Holley one but the connector is the same and so is the hole that the sensor pushes into. 

The nipple on the sensor was also off center slightly but it was real easy to make it fit.

 

To make them work I had to:

Cut the top retaining clip off the new sensor with a pair of dikes so it will clear the underside of the air cleaner mounting flange.

When installing the sensor, rotate it slightly counter clock wise so the screw hole in the metal clip that is used to mount it to the throttle body will line up correctly. 

Bam done, easy.

NO modifications at all are needed to the TB or its wiring etc.

[Tony D]

I've ended up with a Commander EFI, two Megasquirts, two SDS units, and an 1100CFM air door like this to go with the setup on the Z (that's  a Novi Centrifugal Supercharger installed now going on 24 years....  with original analog EFI --- you know, turn the trimpot knobs for gain and such...)

 

Recently my eyes have turned to the 66 Corvair Corsa Turbo I have, being that I have the four barrel conversion manifold for it, and enough 6 cylinder EFI's laying around along with the air door...

 

I used to put Datsun EFI on Corvairs (hahahahaha, how times change!) and think I will skip my ECCS retrofit phase and just go direct to aftermarket on this one...

 

You think the Datsun is cold blooded with a four barrel....try a Corvair at -35F with a big Holley on it and a cam that produces no vacuum whatsoever until about 2,200 rpms and no way to get heat to the plenum under the carb!!!

 

An FYI on the L20A SU setups. The early setups without the heating on the manifold had built into the phenolic spacer a stainless steel ring with little winglets about 5mm high and 3mm wide all around the circumference of the hole at about a 30 or 45 degree angle. It obviously turbulated the airflow, or imparted a strong swirl to the incoming fuel air mix.

 

Some TBI setups have ridges machined into the manifold spacer to impart similar swirl. I think that might help as well...

 

What you missed was my latest 4WD Turbo Acquisition:

Edited December 19, 2013 by Tony D

[SuperDan]

I've ended up with a Commander EFI, two Megasquirts, two SDS units, and an 1100CFM air door like this to go with the setup on the Z (that's  a Novi Centrifugal Supercharger installed now going on 24 years....  with original analog EFI --- you know, turn the trimpot knobs for gain and such...)

 

Recently my eyes have turned to the 66 Corvair Corsa Turbo I have, being that I have the four barrel conversion manifold for it, and enough 6 cylinder EFI's laying around along with the air door...

 

I used to put Datsun EFI on Corvairs (hahahahaha, how times change!) and think I will skip my ECCS retrofit phase and just go direct to aftermarket on this one...

 

You think the Datsun is cold blooded with a four barrel....try a Corvair at -35F with a big Holley on it and a cam that produces no vacuum whatsoever until about 2,200 rpms and no way to get heat to the plenum under the carb!!!

Actually, I know exactly what you are talking about. My very first car when I was 16 was a 1965 Corsa with the 140hp engine, bought it for $400. The 4 Rochester carbs on it were trashed from the previous owner over tighting them and I converted it to the single 4 bbl setup.

Cold blooded is an understatement. Even living in the southern desert of California on a 120deg day, you could fire it up and wait 10 mins, then grab one of the intake tubes and it was cold and sweaty like a can of beer.

I ended up doing what you mentioned above with copper mesh screen to help with the cold drive ability. It help some but in the end I ended up making a spacer between the carb and intake flange that routed hot engine oil to help. It made the biggest difference.

Getting another Corvair has been on my radar for the last few years, I really want another 65-66 Corsa Convertible that I can convert to EFI.

[Tony D]

Try it at -35F on an ice racing track! We never thought to use oil heating to warm the plenum bottom... It just idled at 2,200 which was cool since it's really not on the cam until about 3,800-7,500!

 

If we coulda had Weber 3C's, we would have!

[280zex]

Honestly I personally have to say that running the holley/turbo is my favorate. All 6 plugs have that golden brown coloring. One thing I did learn is that this beast does take some time to warm up and peak performance comes with 200 deg f coolant temps.

 

The last thing on my check list is to manufacture a custom pump shot cam, im currently running the green cam on hole 1 and its ever so slightly late in its function compaired to the throttle opening. I need to get that shot right on the edege of the throttle opening and right now its off by about 10 deg of throttle opening.

[NewZed]

To 280zex - You have the ZX fuel rail cooling setup, I see, pointed generally at the carburetor.  Is it on a temperature switch or manual, and when does it come in to play?  Just curious.

[280zex]

To 280zex - You have the ZX fuel rail cooling setup, I see, pointed generally at the carburetor. Is it on a temperature switch or manual, and when does it come in to play? Just curious.

Thermally switched, 170 deg f, sensor has been moved to under thermostat. I need to post new pictures of the engine compartment, i moved tome things around for optimization.

[ozconnection]

Honestly I personally have to say that running the holley/turbo is my favorate. All 6 plugs have that golden brown coloring. One thing I did learn is that this beast does take some time to warm up and peak performance comes with 200 deg f coolant temps.

 

The last thing on my check list is to manufacture a custom pump shot cam, im currently running the green cam on hole 1 and its ever so slightly late in its function compaired to the throttle opening. I need to get that shot right on the edege of the throttle opening and right now its off by about 10 deg of throttle opening.

What type of accelerator pump diaphragm valve do you have on your Holley?

 

I had the best results with the umbrella type found on the more modern bowls. The older style with the captive ball bearing isn't as crisp and takes time to seat and the shot delivery lags behind the throttle opening.

 

Is there a phenolic insulator between the heat shield and the carb at all?

 

I love this thread....

[280zex]

What type of accelerator pump diaphragm valve do you have on your Holley?

 

I had the best results with the umbrella type found on the more modern bowls. The older style with the captive ball bearing isn't as crisp and takes time to seat and the shot delivery lags behind the throttle opening.

 

Is there a phenolic insulator between the heat shield and the carb at all?

 

I love this thread....

Old style diaphram. The throttle base plate was former racing equiptment, and i highly modified that. Now the throttle shafts close at a further rate than before, this causes pump cam misallignment.

 

Custom 3 piece heat shield this material from boeing samwiched in the middle. Thermal resistance is good to 10,000f or so says my engineer friend. There is also more heat shielding behind the shielding you see.

[ozconnection]

 

I got serious and managed to get a final figure of 159.1 rwkw which converts to 213 rwhp. NA. Megasquirt. 

 

There's certainly nothing too wrong with the Clifford if it can support this much power. Ignition is standard 280zx dizzy, 20 deg. static with 30 total.