TWEETY's biggest regret

Tweety · Post by **Tweety** » Wed Feb 06, 2013 9:30 am

Everything about my Subaru conversion and his subsequent SC12 supercharger addition has been what I wanted it to be.

Regular readers will recall how I converted my VW 1916cc powered unit for the ea81. Many people mainly from the Aussieveedubber site asked WTF? why not EJ, say EJ20 with few cc's extra (good for Vicroads reports) and all round improvement except- no EJ or other modern engine with an accessible adapter plate was my choice due to my own needs of a simple older engine for ease of maintenance etc.

The supercharged ea81 is woeful with economy. This is my reason now for regret. Without the SC it was ok but not real ball of fire and I could have lived with it easily except when towing a trailer or van and as I do so often a SC was needed in my view.

Now the SC has given me extra low down and mid range actually all range power. It moves very nicely indeed. But of course I only use this benefit sparingly.

I've messed around with dynoes, jets etc and beleive that I have the right combination to at least give me the best economy I can possibly get. Jets are 150main 50 idles. Dellorto 40 dhla carb.

ECONOMY is: regular riding 13-14 L/100kms Towing 18 L/100kms Range 220km-310kms 47 litre tank weight Trike 580kgms, van 500 kgms. Non supercharged economy 8-11 L/100kms Towing 12 L/100kms

Cant fit a LPG tank on it as that might be an answer. I think the only answer, as I have 2 other vehicles and this is recreation...just swallow it like the engine does.

But when you think of the EJ and say 7 L/100kms it saddens me that really I've gone the wrong option. I'm also not happy to reconsider and go to the trouble of another conversion nor twin carbs etc. Cost being the issue now as poor health issues has me off work for a few months and I've spent enough. Bare in mind the wow factor is there. People are amazed at a brumby engine supercharged and many say "I had a brumby".

I like the whole concept. I never received concrete info about economy prior to the conversion. A beetle owner did a conversion but didnt record his economy before he ripped the engine out for another project. Except he said "the fuel gauge doesnt seem to move faster than previously".

open for chat.

steptoe · Post by **steptoe** » Wed Feb 06, 2013 12:22 pm

Pretty brave of you Tony to be open, honest and frank about your tinkering and thoughts. Some, make the mistake, don't share it and leave a topic just drifting, or just keep mum and let someone else work it out for themselves.

We've all enjoyed your journey so far I am sure, I have anyway. You have gone beyond what many of us have dared, and done it pretty quickly too. Often felt my tinkering with EA82T and LPG was not pioneering but gees , was hard to find anyone else going down exact same track, or been down it, to give advice or add some foresight to the project.

I'll think no less of you for going back to normally aspirated for your sanitys sake, and yer wallet

, couldn't you still pull a wheelie pre supercharger ?

Now, if only a stroked EA81 had been done ......

Hope your health improves soon mate !

niterida · Post by **niterida** » Wed Feb 06, 2013 12:40 pm

one word : MegaSquirt

steptoe · Post by **steptoe** » Wed Feb 06, 2013 1:45 pm

Can just see Tony stumbling across an old camira and see its injection system as a worthy donor ..... Camira ? Gees , about as rare as a Marina

Tweety · Post by **Tweety** » Wed Feb 06, 2013 4:42 pm

Megasquirt....dictionary...mega means "huge (t'is why some call me 'megaman')

squirt...meaning. small amount of fluid propelled.

Megasquirt means huge small amount of propelled fluid eg fuel.

So I assume Niterida that Camira 1.8 (drove a local government model think it had the odd looking headlights) has this fuel injection system you speak of. so number of questions

1/

niterida · Post by **niterida** » Wed Feb 06, 2013 4:45 pm

No - its an aftermarket, build-your-own system : http://www.diyautotune.com/

Tweety · Post by **Tweety** » Wed Feb 06, 2013 4:50 pm

Thanks Jonno

Megasquirt....dictionary...mega means "huge (t'is why some call me 'megaman')

squirt...meaning. small amount of fluid propelled.

Megasquirt means huge small amount of propelled fluid eg fuel.

So I assume Niterida that Camira 1.8 (drove a local government model think it had the odd looking headlights) has this fuel injection system you speak of. so number of questions

1/ Cost
2/ Ease of install
3/ Would the injection (I assume there is only one) be between the carbie and SC like where the water injection is on Tweety or where the blow off valve is between the sC and the manifold.
4/ What improvement would there be and why?

I have another thought. Why not replace the carbie with a single throat carbie? Or like Toonga once said that one throat could be reduced in jet sizes to say 100. With the dellorto 2x150 mains a single throat carbie 1x150 or 180 migth be almost as efficient and more economical??? an SU?

Of course I've read up a lot. Compressed air eg boost means more air equals more fuel. Even at idle the boost gauge might say -8 but its still has small boost as I understand it. So cruising around at 100kph or 90 at -3 doesnt mean you arent sucking fuel at large proportions....megasuck hehe... and therein lies the issue with draw through set up. blow through might be an answer because you can use the on/off switch on a pulley from pulley brothers. They arent cheap either. in fact no answer will be cheap.

Tweety · Post by **Tweety** » Wed Feb 06, 2013 5:02 pm

thanks Niterida we crossed posts. will read up on this.

steptoe · Post by **steptoe** » Wed Feb 06, 2013 5:24 pm

I seem to recall in the early days of this forum, likely pre 2006 crash, someone had been tinkering with an efi system off a Camira. I cannot recall if it was a multi point or throttle body injection. Aparently the beauty of the Holden system back then was a memcal chip ? that could be hooked up to a computer of its day and reprogrammed - allegedly.

Once saw and admired a multi point injection off say an XE 4.1 Falcon six grafted to a legendary 2V250 manifold of the XY & XA era. Never saw or heard it run but looked impressive the way the inlet had been drilled and bunged up for injectors ....

niterida · Post by **niterida** » Wed Feb 06, 2013 5:54 pm

steptoe wrote:I seem to recall in the early days of this forum, likely pre 2006 crash, someone had been tinkering with an efi system off a Camira. I cannot recall if it was a multi point or throttle body injection. Aparently the beauty of the Holden system back then was a memcal chip ? that could be hooked up to a computer of its day and reprogrammed - allegedly.

All GM/Holden computers (at least up to 1999) are the same - Camira or Corvette doesn't make a difference !! And they are easily changed to be totally programmable. Probably pick an ECU up for $50 but then it will cost
a bit to modify it. See here : http://www.kalmaker.com.au/

Silverbullet · Post by **Silverbullet** » Wed Feb 06, 2013 6:15 pm

It definitely wasn't wasted journey Tony, you have showed us all so much! Now we know the pros and cons of a S/C EA81 with a draw through setup, I'm sure everyone who's followed your journey has been impressed with your work. And don't tell me it wasn't worth the effort when you feel the boost kick in?

That's what I like to see, questions and plans for the future improvement a few posts after the regret post

Keep it up and get well soon!

Subydoug · Post by **Subydoug** » Wed Feb 06, 2013 8:10 pm

Your work inspired me to bite the bullet and try supercharging my EA81. I did it more in a "why not?" attitude rarther then wanting or needing more power. I like to tinker

.

The way forward from where you are now Tweety probably involves EFI, clutched SC pulley, intercooler and all that comes with it. Only then will the fuel economy be better. One other thing you could gamble is running blow through carby like I am. Only boosts when you want so fuel economy is pretty similar.

When I swapped from my 3spd auto to the 4spd man My fuel consumption dropped from around 12-13L per 100kms to about 8-9L....and that is city driving only.

What I am seriously considering doing though tweety is rebuilding my motor, but going all out. Oringed heads, 10-1 CR, light porting in the heads, 5 angle valve seat cut, either Dual carby (ITB style

) OR EFI with ITB's, Custom exhaust, all that sort of stuff.

If I do go down that route Il let you know how it goes

.

Regards

Doug

Tweety · Post by **Tweety** » Wed Feb 06, 2013 8:32 pm

Thanks a lot guys.

Plenty of reading to do now. I love the boost. Even at a modest 5psi its wodnerful. 110 kph up a mountain that previously was flat out in 2nd gear at 60kph means a big difference.

Seems megasquirt or blow through is the answer. Blow through will take work over winter if I can find a carbie I can pressurise. What kind of carbie have you used Doug?

I wrecked a clutch pulley to make a fixed pulley. I could get another from Pulley bros. and smaller too so that'll give me more boost still say 10 psi (who need cocaine).

While I'm reading up on megasquirt please supply us with more detail on your blow through set up Doug. I'm very interested. pics?

Brumby Kid · Post by **Brumby Kid** » Wed Feb 06, 2013 9:52 pm

I KNEW IT!!!
When you said that was it for modifications Tony I never believed a word of it.
I knew there would HAVE to be more coming. Hehehe
I'm going to watch this space, should be interesting indeed.
Would a blow through system be any different? I don't know the differences.

Cheers Cam

steptoe · Post by **steptoe** » Wed Feb 06, 2013 10:02 pm

Tell you what on boost pressures don't think I feel any more beyond 8 psi and only really keep it set at about 12 so I don't get the flutter when it hits the preset of the boost controller.....

atta boy Tony

Post by **TOONGA** » Wed Feb 06, 2013 10:09 pm

Tony before you go blow through try the setup with out the water injection. you may find you will you have to retard your timing to stop the ping but it could increase your MPG or KM/L.

Doug is using a stock standard weber 32/36 with 3-4 PSI of boost from memory.

TOONGA

Tweety · Post by **Tweety** » Wed Feb 06, 2013 10:48 pm

I can easily disconnect the water injection system. It isnt much use under 6psi anyway so will try that Toonga.

Cam...you inquisitive adolescent you!

Draw or suck through is what I have. From the air filter it goes to Carbie then through the supercharger that makes pressurised air and fuel mixture then to manifold to engine. Positives- gets you horny. Easy install with few complications. Negatives - poor fuel economy causes impotence. SC runs all the time causes more wear (but SC12's are a dime a dozen)

Blow through. From air filter goes to supercharger then that blows pressurised AIR ONLY through a sealed carbie to engine. Positives: you can have a clutch on the SC so it can be on/off when you need it meaning normal economy when not on like cruising the freeway and not towing. Negatives: You need a sealed carbie, no brass floats that can/likely collapse, (you can buy these carbies as a kit and some are Weber 32/36), has more complications on install. Needs a wastegate me thinks cause where does the air go after the butterfly shuts? And where does the air get drawn in when the SC stops? So many questions- so little knowledge lol.

Subydoug · Post by **Subydoug** » Thu Feb 07, 2013 12:26 am

Tweety,

Yeah stock 32/36 weber on standard ea81 intake manifold. Just put a k&N Plenum top. Blow through has its complications though. You need to run a high pressure fuel pump with a boost regulated Fuel pressure regulator. The reason being that as the pressure rises inside the carby the fuel pressure that was fine N/A cannot hold the needle valve off the seat. I use a 1-1 rising rate reg so for every PSI of boost I produce my fuel pressure goes up 1 psi as well. Using a bosch 044 EFI pump drawing from a surge tank, straight into the reg and back into the surge tank. Saves running a new return line. Also need a BOV (Two of them if they are small) or Bypass valve. At idle, the pressure between the SC and weber was pretty high without it, high enough to make my v-belt slip. Also increases parasitic drag and your more likely to pop a pipe when you shut the throttle at high RPM's. Tuning the weber was easy as pie. I didnt have to change it from N/A.....and I know its not leaning out because I have a wideband O2 sensor installed.

All in all, it was pretty hassle free install, engine misfires when cold and every now and then due to a crappy coil.....some cold 7's fixed that but fouled up bad when I had a fuel issue....back to 6's for now.....Next chore is the intercooler.

Dont really have any photos so I just took some for you,

Plenum on weber

BOV assembly

Supercharger. Mind my tray dodgy welding

About my 4th different setup for an "airbox" Trying to lose some induction noise. This seems to be the quietest so far. Just got in the mail today some sound insulation for turbos to try.

Little AMR is pretty much running flat out. Might have to drop in a sc12 instead.....but maybe not......I have plans.....

If you start pushing boost levels of around 10psi you may need to drop your static Comp ratio....will cut the pistons some slack

Regards

Doug

steptoe · Post by **steptoe** » Thu Feb 07, 2013 7:35 am

Those pics speak a thousand words , as usual

A good reason to keep those hefty AC brackets !

A note for Cam on blow through V draw through - think it all means you either have the turbo blow fresh air only through the carby, or you have the turbo draw the mix through the carby. The first puts the carb under pressure, where the latter keeps the carby and its guts at atmos in places like the float chamber.

I've done both with LPG. First up the turbo blowing air through the gas carby as the manufacturer and its Australian agents, and US techs insisted it be done. Was not driveable beyond just around the block - due to turbo fours, maybe flat fours having odd intake manifold pulses - upsetting the whole converter supply harmony with the carb.

So, went the way they insisted SC and LPG in draw or suck through AIR FILTER>GAS CARB>TURBO>THROTTLE BODY>INLET
I made the mistake of reading more and more turbo / LPG applications around the world and found people were planting a throttle before the turbo causing the need for different seals in the turbo to deal with other issues, problems they were getting etc - filled my head with worries....
The first guy I ever spoke to on turbo and LPG told me simple > air filter, carb, turbo, throttlebody - threw all the other info aside, went this way, dealt with the vac advance line blowing vapour inside the dizzy through buggered diaphragm (read 5 months of backfire under boost

) So far, about 80,000km of mostly fun

with fuel average about 12l per 100km of LP

Tweety · Post by **Tweety** » Thu Feb 07, 2013 8:29 am

Thanks Doug for your trouble taking pics. Great stuff.

My panther trike doesnt have a return line. been using a 2-3 psi electric fuel pump and runs well. the trike has a very large 50 litre tank made of alloy as part of its monocoque chassis so to put another line in there would be a pain.

Just one of the few issues to be conquered in reconfiguring the suck to blow conversion. The work and the fiddling doesnt encourage me. Frankly my wife is fed up with me fiddling so short bursts....while she is asleep lol ! is the go. Cant say I blame her the SC install last year was to take 3 weeks but took altogether 8 months. Surge tanks, rising rate fuel regulators etc seems bit daunting to me.

But to continue with the issues the SC12 is quite large. Even under the spacious Tweety engine bay it wouldnt be easy to remount it to allow for carbie (say 32/36)to bolt in its original location on the manifold. Where my SC12 is now it would need to move 50mm towards the Alt...it has 15mm clearance. The correct mounting of the SC12 took me a long long time.

Doug if your system was more straight forward then I'd be interested. As you described it- its a bit over my little head.

Pity I cant just have a electrical solonoid to shut off on throat of the dellorto. Or a way of - at a switch making the SC12 pulley just turn over without boost to allow for N/A workings. Why mechanical stuff is all so much work is beyond me. T'is why I'm making some cubby houses....wood...is forgivable...