Supercharger for Subaru?

Tweety · Post by **Tweety** » Mon Mar 26, 2012 9:35 am

Does anyone know of the easiest brand of supercharger that can be bolt on power with very few mods on an Ea81?

I know turbos are more popular etc but compression reduction etc makes them less desirable from my thinking.

A few things- cost, fuel consumption predicted, ease of instal, brand, power increase for towing etc.

No I'm not serious about putting one on my trike.....and no I dont regret putting in an EJ20 instead of the ea81......

Just asking.....pondering.....dreaming!

YouTube · Post by **El_Freddo** » Mon Mar 26, 2012 11:04 am

Going fishing eh mate??

I'd be going for the Toyota SC12 super charger. Good unit, good output and a stand-alone unit so you can bolt it where ever you can make a bracket for it. Your hardest part will be making the carb sealed to handle the boost.

It'd go sick on your EA81. Also if you get the clutch fan pulley you can turn it on and off "mad max" style

Since Subarino has done it on his EJ'd hatchie and riding in that it's always been gnawing away back there. And now that Taza's having a go at it I'm getting closer to making a move on it - plus I've got a mate with a liberty that was looking at a turbo for better performance and I told him about this mod that is easily reversed...

But we'd be looking at the larger SC14

Cheers

Bennie

Davidov · Post by **Davidov** » Mon Mar 26, 2012 11:51 am

Taza and I are currently in the middle of a project to SC14 supercharge both his EJ20 and my EJ25. Hardest part is the mount since it must be mounted off the engine itself.

A SC14 unit can be had for $350-400. Then gear like BOVs, possibly an upgraded carby for the EA81, and piping etc. In total your looking at $<800 hopefully.

Tweety · Post by **Tweety** » Mon Mar 26, 2012 2:52 pm

I'd be going for the Toyota SC12 super charger. Good unit, good output and a stand-alone unit so you can bolt it where ever you can make a bracket for it. Your hardest part will be making the carb sealed to handle the boost.

It'd go sick on your EA81. Also if you get the clutch fan pulley you can turn it on and off "mad max" style

mmmmmm, interesting...very interesting Bennie

off the engine itself.

meaning? me no kabish!

In total your looking at $<800 hopefully.

within budget some time later in the year.

I assume there's be more pull when towing. Dont get me wrong- ea81 is adequate. But reserve power! mmmm Economy? does it suffer?

Tweety · Post by **Tweety** » Mon Mar 26, 2012 3:01 pm

but Bennie read this:

http://turbo124.com/forum/viewtopic.php ... light=sc14

quote:

I have spent the last two years superchargeing an 8v 2L engine. The first year was spent wasting my time with three 1ggze sc14 superchargers. All of them ended up blowing oil seals, which replacements can not be found in australia.

First setup used a 48 DCOE carby. Was great to 5 psi but anymore and i couldn't get fuel to the engine fast enough and it would backfire as it went lean and then stumble as it went rich.

Then i hocked up injection using camira injection mounts with 13b injectors. This setup worked fine on low boost but didn't like anything above 9psi. Water injection helped but i would still regularly see 135c inlet temps. Ended up blowing three superchagers.

Final setup uses an eaton m90 supercharger. This with a bypass setup has worked the treat. Can easily make over 200 rwkw with just under a bar of boost. Looking at it now an m62 may have been the better way to go with around 12psi of boost, beyond that the m90 is probably the better option. you would be much better utilising one of these superchargers. They are a far more efficient design than the toyota blower and can be bought cheaply in the US as they are very common on the ford thunderbird.

unquote.

your views?

Davidov · Post by **Davidov** » Mon Mar 26, 2012 3:09 pm

Tweety wrote:
meaning? me no kabish!

The supercharger must be mounted in the engine bay off bolts on the engine. This is because the engine moves, if the charger were attached to the body of the car the engine movement would snap the belt from the charger to the engine pulleys, or rip the body itself.

Tweety wrote:but Bennie read this:

http://turbo124.com/forum/viewtopic.php ... light=sc14

quote:

I have spent the last two years superchargeing an 8v 2L engine. The first year was spent wasting my time with three 1ggze sc14 superchargers. All of them ended up blowing oil seals, which replacements can not be found in australia.

your views?

This is probably because he is trying to push an unreasonable amount of boost out of this little supercharger. The sc14 is low end stuff, between 5-10psi tops.
So it wont be mind blowing turbo like at all, it will be a decent torque and performance boost. Stock NA subi engines cant really handle anything more without modification.

Tweety · Post by **Tweety** » Mon Mar 26, 2012 3:42 pm

Thanks Davidov

Read up a bit on the web. the pulley on the SC12 is flat toothed. a V belt could replace it and its from a Sigma A/C unit.

I have a fair bit of room on top of my ea81 especially soon as the radiator will be moved form above the transaxle to the front of the trike. Seems after reading up the SC12 will suffice. I wouldnt want much more power than what I have and dont want to

-lose reliability
-carry out internal mods
-lose economy (which I'm really enjoying after the VW aircooled engine) I'm constantly getting 9-10L/100kms now.

Finally it seems there are many SC12's on the market with owners wanting to go up to SC14 for high performance reasons. Might be some cheap opportunities there.

I dont know anything about the plumbing of the SC. Would it be hard to do or can I purchase bolt on things. it has the weber 32/36.

Silverbullet · Post by **Silverbullet** » Mon Mar 26, 2012 7:44 pm

Can you really put any boost pressure through a carby? push through or pull through I would have thought it would be too much for the butterflies or might make something else go "pop"

Would be interested to see how it goes.

BaronVonChickenPants · Post by **BaronVonChickenPants** » Mon Mar 26, 2012 8:24 pm

Sorry to be the bringer of bad vibes, but I have explored this possibility myself and found the following flaws in the theory:

The standard EA81 does not take kindly to forced induction due to it's long intake passages, the dual inlet twin carb EA81 or EA81T heads would be required to overcome this. Unfortunately these are rare and big $$$.
Most carbs do not handle being pressurised as their basic principles rely on suction and gravity to get fuel into the engine. Positive pressure will usually just force air backwards through the fuel jets emptying the fuel bowl. There are carbs that are designed for positive pressure, unfortunately these are rare and big $$$.
One alternative is to run the super charger in a suck through arrangement, but unless the charger is designed for it, this will drastically shorten it's life expectancy.
Another is to adapt an EFI system in place of the carby, the SPFI systems from Camira's or EA Falcons are common choices.

In short, to do this properly will require a lot of time, a lot of expense, a lot of trail and error and result in an overly complex and potentially unpredictable beast for minimal gains.

For a reliable increase in power an EJ really is the way to go, even just an EJ18 is a nice unit.

Jordan.

Gannon · Post by **Gannon** » Mon Mar 26, 2012 8:36 pm

Like this?

Link to USMB page Superoo 72 GL racecar

Tweety · Post by **Tweety** » Mon Mar 26, 2012 11:37 pm

mmmmm this is getting interesting.

I enjoy counter claims and reasons for them.

So anyone carried out the inclusion of a SC on an ea81/2 and have a report for us?

Cost
Powe rincrease
ease of fitting
anything else...

steptoe · Post by **steptoe** » Tue Mar 27, 2012 8:07 am

Next thread by Tweety will be on the VW sites looking for a 2.0 kombi auto beefed up to take the extra power

Maybe get another EA81, build it a bit wilder, shave the crap out of the heads, some porting, a cam, weber, shift kit on the auto k-whump changes

YouTube · Post by **El_Freddo** » Tue Mar 27, 2012 4:22 pm

Tweety wrote:I assume there's be more pull when towing. Dont get me wrong- ea81 is adequate. But reserve power! mmmm Economy? does it suffer?

Economy, well that all depends on a few aspects that I'm sure you'll be familiar with so I won't go over them again. One I will mention is that with any forced induction you're going to use more fuel, but the economy can be made up with the way it handles hills etc without struggling or need for down shifting.

Tweety wrote:mmmmm this is getting interesting.

I enjoy counter claims and reasons for them.

So anyone carried out the inclusion of a SC on an ea81/2 and have a report for us?

Unfortunately I can't think of anyone that has. BVC has some good points to think about that I hadn't considered, but I also wonder if these are primarily for a turbo application that goes from non boost to full boost very quickly in the rev range where as a SC once it's on is pretty steady throughout the rev range...

Really though, after reading what BVC has said I'm feeling over my head about helping you with this unless you went with the EFI route, but as you're looking for reliability I wouldn't suggest going for the custom EFI on the EA81.

Cheers

Bennie

Tweety · Post by **Tweety** » Tue Mar 27, 2012 8:58 pm

the following is a reply eamil sent to me form Scott Hardwick of CAPA

Subject: CAPA website feedback form
---------------------------------------------------------------------------

comments: One very desirable VW style trike
would make ideal promo machine for your product if I go ahead. My inital enquiry is if my Subaru engine would be suitable for a supercharger. Seeking modest power/torque increase (if bolt on is easy). Is mated to a VW auto 3 speed trans from a VW fastback. Carbie is a common 32/36 twin throat Weber. Possible? rough price? have you doen an ea81 Brumby engine before?

answer

hi there,

definately possible to do, i would look at the Eaton M-62 unit and do a draw through setup with an SU or similar carby... You will then need to hook up a belt system to drive and do electronic ignition setup (with boost retard)

regards,

scott.

see http://www.capa.com.au/eaton_m62data.htm

YouTube · Post by **El_Freddo** » Tue Mar 27, 2012 9:05 pm

Sounds promising!

You should also find out if that supercharger can be used when the charger is not in operation - so there's an electro-magnetic clutch on the front of it so you can decide when it's going to be used. Best of both worlds there.

Did you get a rough figure?

Cheers

Bennie

Tweety · Post by **Tweety** » Tue Mar 27, 2012 9:14 pm

The "kit" has a price on the web site. $2800. and that wouldnt include the SU carbie or anything else.

This is still a possibility though at a much later date, before our round Aust trip in 2-3 years time. Whereas a Toyota S/hand unit would be possible later this year etc.

I suppose if this is promising I'd be better off going to a supercharger installer exper tin Melb and ask them to install a Toyota one and get them to do the carbie stuff.

But yes, it looks promising alright

Tweety · Post by **Tweety** » Sun Apr 01, 2012 8:43 pm

This is impressive. anyone know of this brand of SC? have emailed them for more details esp price etc. seems compact for a twin shaft job.

http://www.sprintex.com.au/sprintex/superchargers/

and aussie made

YouTube · Post by **El_Freddo** » Tue Apr 03, 2012 8:11 pm

That unit seems a bit on the light side of things - but it seems that it will also service the EA81 perfectly.

Do I hear custom manifold

Cheers

Bennie

Tweety · Post by **Tweety** » Tue Apr 03, 2012 9:48 pm

and very very compact.

Custom manifold? well everything else is custom!

steptoe · Post by **steptoe** » Wed Apr 04, 2012 7:22 am

of your mention of LPG as the fuel on another thread, some of the longer on the board members might recall "Brumberty" Matt who had an EJ22? in his Brumby - he supercharged it using LPG to simplify things advanced search LPG by BRUMBERTY ....