Mild(ish) mods to an ea81 ?

tim dyver · Post by **tim dyver** » Tue Sep 11, 2007 8:32 pm

Hello All,
I am too incompetant and lazy to consider fitting an ej motor to my ute. i also cant be trusted with that much power. However i have bought a spare motor to play with,and am wondering if any of you guys can remember what you did to your motors before fitting an ej.
I am looking for the specs for a head deck, and a cam regrind, all clues welcomed,
Thanks Tim

90brumby · Post by **90brumby** » Tue Sep 11, 2007 8:55 pm

this is comin from me who spent like 1500 buks on a ea81

dont bother with it tooo much

put a webber on it TWIN PORT heads if u can find some and a cam

but i wouldnt bother

EDIT the ej22 conversion is fairly easy and sooooo much betta

BRUMBERTY · Post by **BRUMBERTY** » Tue Sep 11, 2007 9:08 pm

we will help you.

I wish I didn't bother.
I wish I listened to others early on (Brett, Ian, Grant, Stuart etc),

Go EJ.

If not.......

Weber, search and you will find.
32/36 I think is the one.

A cam is a pain as you need to split the block to get them out..
But a mild grind apparently helps.

Exhaust..leave the Y pipe but open it up after that as far as you can, 2 1/2 inch max.

EA71 (1600cc) pistons will raise the compression ratio remarkably...came in the series 1 Brumby and will bolt right in.

Good spark...get the best dizzy you can, and the best coil...run good fuel and advance the hell out of it.

Ask.

Best of luck

mattl200 · Post by **mattl200** » Tue Sep 11, 2007 9:15 pm

gt40t coil new dissy cap, leads and ngk iridium sparkplugs

u have to order the plugs pre gapped 1.2mm gt40 coil or .8mm standard coil
and advance the timing as far as u can go without it pinging mines at 12deg never pings with 98oct fuel

and ive had iridium plugs in for 20000k look nearly as clean as the day i put them in

MY_STI · Post by **MY_STI** » Tue Sep 11, 2007 9:56 pm

For a quick hit, the linkage for the second throat on the carb can be 'joined' with another linkage using a short peice of looped wire to effectivly make it mechanical instead of vacuum.
There is pics floating round somewhere, but its not too hard to figure out.

And definatly open up the exhaust, despite popular opinion an engine 'needs' very little, if any backpressure.

But if your looking to spend some money, then ej is the way to go.

subelover · Post by **subelover** » Wed Sep 12, 2007 9:16 am

all gr8 posts and nice mods to an Ea81 but my 2c def worth putting an ej in between the front struts m8

an Ea will never be as good as an Ej imo

dfoyl · Post by **dfoyl** » Wed Sep 12, 2007 12:09 pm

Tim,

Send a PM to generaldisorder on usmb (http://www.ultimatesubaru.org) for a cam profile that's he's had good results from.

I don't think there's any signficant benefit from head work on the EA81. EA71 higher-compression pistons will gain you a little but will basically require use of P-ULP (and they're pretty htf here).

Weber or an imported SPFI are both mild performance options - I'm in the process of the latter now but requires a fair bit of setup for it to work (my current hold up is the need for a complete L-series MPFI y-pipe for the O2 sensor).

I've also heard extractors are NOT a good idea for the EA81.

Dean.

Jack · Post by **Jack** » Wed Sep 12, 2007 2:43 pm

The EA81 (while not a rocket) isn't a bad engine.

Mine has done over 350,000km and is still quite reliable. Off road, about the only gripe I have is fuel starvation on steep slopes - the engine just runs out of puff and I come slowly to a slow halt. When that happens, it's simply a matter of reversing back to a flat spot and trying again.

My EA81 Brumby keeps up with EA82T and EJ22 converted L series' off-road, and in many ways my stock Brumby is a much more reliable vehicle than a modified L series.

I'm still on the original gearbox, where as I know of some modifed L series' that are on to their 2nd (or 3rd) gearbox. I won't mention broken strut tops on this thread as it'll cause too much of a topic tangent.

Yes, I'd love to have a bit more power down low, but I've learned to make do with the equipment I've got. I haven't received any complaints from those with whom I've played.

Jack

Gannon · Post by **Gannon** » Wed Sep 12, 2007 5:59 pm

dfoyl wrote:Tim,

My current hold up is the need for a complete L-series MPFI y-pipe for the O2 sensor.

Dean.

I have one that im gonna throw out, but its a kinda long way to post it.

Matt · Post by **Matt** » Wed Sep 12, 2007 9:15 pm

I agree with the EJ comments, I have most of the mod's listed above and i now know the EJ would have been cheaper in the long run, however i like my EA81 because it is simple and basic tools can fix everything. The amount of effort for a cam (I can post Pics), etc is pretty big, possibly bigger then putting the EJ in. But if you want to keep the stock engine and play with it the Weber is one of the best starts and go from there....

steptoe · Post by **steptoe** » Wed Sep 12, 2007 9:29 pm

it is the manifold design that sucks on the EA81. Your spare inlet manifold a 32/36 weber adaptor plate and a machine / weld shop is what will give the best easy improvement. Get them to machine a bigger hole in the manifold to match the weber adaptor with the carby in best orientation for accy cable. I spent just on a grand in 2000 on a rebuild and 16/56 watson race cam and then later the twin carbs. I got a very reliable revvy racy little beast that finally succombed to main bearing surface tearing away after about 180,000 km. Best thousand bucks i ever spent on a car!! keeping it nearly stock was less hassles. But then look at what i am up to now - (edit - all I wanted to do was turbo the EA81 for more go) -still no EJ though

EDIT and get them to weld the adapter in place

rtcb65 · Post by **rtcb65** » Wed Sep 12, 2007 9:46 pm

I agree with Jack. The old EA81 is no rocket, but is reliable. They must be, if they put them in planes. I have the same problem. running out of puff . Yet a friend has the same car with less mods and he made the hill first time. Go figure. I wont be doing ej conversion. If i break down somewhere aways from home , i am more likely to find a standard subaru in someones back yard to request a part from than a mod one.

If people dissagree, please say why. i would like input.

Matt · Post by **Matt** » Wed Sep 12, 2007 9:47 pm

It depends on what size intake you have there is 2 sizes, Brumby (i believe) all had the smaller size one and Wagons had the larger. Something to look at anyway..

BaronVonChickenPants · Post by **BaronVonChickenPants** » Wed Sep 12, 2007 11:18 pm

I don't understand why people keep recommending the GT40 series coils, they are designed for points ignitions and are severly under rated for electronic distributors, even a standard electronic coil is rated higher, although their performance may have deteriorated over the past 10-20 years.

As for performance options, have a look at this sticky.

Jordan.

AndrewT · Post by **AndrewT** » Thu Sep 13, 2007 5:24 pm

rtcb65 wrote:I agree with Jack. The old EA81 is no rocket, but is reliable. They must be, if they put them in planes. I have the same problem. running out of puff . Yet a friend has the same car with less mods and he made the hill first time. Go figure. I wont be doing ej conversion. If i break down somewhere aways from home , i am more likely to find a standard subaru in someones back yard to request a part from than a mod one.

If people dissagree, please say why. i would like input.

I disagree....after a conversion part of your car is EA based, part of it is EJ based. Both series of parts are common and relatively easy to find - lots of Libs getting wrecked all the time now.
It's not like your car will be full of "hard to find modified parts". Just an adaptor plate which is very unlikely to break.
That being said, converted cars are usually less reliable simply because you always end up with a weak point somewhere with certain parts under far more load than they were originally designed for.
The EA81 is reliable sure, but an EJ22 is also very reliable. Converted cars don't break down from blown motors, usually things like CV joints or gearbox because of the extra power.
This is all philosophy anyway....if u want to stick with a boring old slug EA81 its still definitely a good choice for reliability's sake.

Matatak · Post by **Matatak** » Thu Sep 13, 2007 7:09 pm

i culdnt see ya havin a prolbem finding most parts either like AndrewT says

unless of course

it was like 90 Brumby's...which most of u probly dont no about but ahhh yer he may have some troubles finding various items if he breaks stuff.....LOL

tim dyver · Post by **tim dyver** » Thu Sep 13, 2007 8:20 pm

Thank you all for your informed replies. I have scoured this list, and USMB and the amount of information on this topic is vast. And of course it varies considerably . I drive my ute in heavy traffic most days, never play in the mud, so all i would like is enough low down excelleration to beat the ma##a 323's off at the lights. A modest enough ambition for an old man fast approaching his dotage. Points about the cam are duly noted, as are all points which start with "hard" or "difficult". I will do the coil and plug upgrade, port and polish the heads etc etc. I already have a 2.5" cat back exhaust. I had a webber/holley on it for 6 months and never got it to run properly. One day it was great, the next day a pig, eventually i gave up in disgust and cleaned up the hitachi and put it back on.Its all in that transition from idle/low revs to throttle, important when battling melbourne peak hours.
Regards ,Tim

schultzie · Post by **schultzie** » Sat Sep 15, 2007 1:43 pm

hey time i am in contact with some one that has something u might like to have.....

Ea81 rally motor, with dual port headders and dual carbies, rebuilt heads ect ect it is in bits and he wants 700 for it, it is in horsham vic...

even has the air cleaner for it...

the blokes old man built areoplane engines and when he died his son sold all the motors except for 1...

150hp ect ect... just get it to where u are and get some one to rebuild it, if your interested ill find his number and get in contact with you