Tweety's ea81 build

Tweety · Post by **Tweety** » Tue Nov 11, 2014 11:01 pm

El Freddo

Reckon my first trip might be Shepparton for a coffee. Might get it sorted before I come though. Make sure its running 90%

A nice ride around the orchids might be on the cards.

YouTube · Post by **El_Freddo** » Tue Nov 11, 2014 11:25 pm

I'll book it in mate!

Might even put a yellow stripe on my helmet to colour coordinate

(too far?!

)

Cheers

Bennie

steptoe · Post by **steptoe** » Wed Nov 12, 2014 6:44 am

don't start it until 2015 so you can claim it is a 2015 MY update, (re)manufactured late 2014

Tweety · Post by **Tweety** » Mon Nov 17, 2014 8:29 pm

Yep, will be a 2015 engine ha.

Some progress here. Got the 6 manifold bolt holes reamed 2.5mm each end by local engineer that built Tweety's roof.

There are always problems. Dummy fit the adapter and two studs protruded too far and hit the carbie. see two pics below.

So in the end I decided to replace all four studs with bolts and ended up with 2mm clearance from the carbie components. problem fixed.

The next problem was the dizzy locking plate. Once the stock ea81 dizzy was in place the vacuum steel pipe would hit the coolant drain pipe on the SPFI manifold. giving very limited adjustment. So with a spare locking plate handy I cut and welded the plate to allow for the fixed not to be about 20 degrees anti clockwise from stock. This allowed for the vacuum diaphragm to clear that small coolant port altogether even with max adjustment.

Next issue was the home made accelerator arm. At its stop position it was resting up against a spark plug lead on the dizzy. So took that off and bent that successfully to clear it about 10mm.

Spent plenty of time on plumbing items. hose from RHS rocker to PCV (and smaller hose to air intake) is mainly hidden as the hose goes around the rear of the engine before making its way to the middle manifold area. LHS rocker cover hoes also goes to the rear then up a little to a mini air filter.

For the main air filter I use a large cone type and as with the mini filter I spray that goop on them. However the cone doesnt suffice in my book so inside the cone I have an easy pull out unit with fine sponge. I've taken the precaution of some tie wire in a # pattern to stop the sponge in the event it dislodges and wants to head for the carbie. More pics next time.

Tomorrow I'm putting on some anti seize on the manifold bolts and bolting that down to the head. Bolt down the carbie using thin layers of carbie gasket sealer.

The Porsche "centre" radiator will be purchased in February (we have to budget) along with 3 x 6" thermatic fans. Exit diameter is 41mm of the radiator so silicone reducers have been ordered from the UK. 41mm>32mm. Radiator is 610mmx170mmx41mm single row. Initially that will be the only cooling item but later a small universal heater unit will be installed up front for a demister and left on all the time hence more cooling capability. Essentially the cooling system I've settled on is a trade off. A few years ago I started with the ea81 engine with a Toyota MR2 radiator mounted directly above the torque converter which meant the thermatic fans came on even at 100kph. That led to an Alfa 33 radiator being mounted up front. Lately I have liked the look of the radiator mounted there. Tweety is all about appearance so it had to go back to the rear. However the Porsche radiator, being so short in height can be mounted above the towball just inside the engine bar and hidden a little by the number plate.

YouTube · Post by **El_Freddo** » Mon Nov 17, 2014 10:52 pm

Looking good mate!

I bet you can't wait to get that radiator and fan setup on the go!

Cheers

Bennie

Tweety · Post by **Tweety** » Tue Nov 18, 2014 6:56 pm

yeh Scott, cant wait alright. But xmas comes and goes quickly.

Finished off the engine today. All connections, PVC hook up, fan belt protector (mandatory on trikes as engine is so open to the public). Waiting now for frog to send me a new rotor button, dizzy "O" ring, dizzy cap rubber seal making cap waterproof.

So, thread to continue around Feb.

steptoe · Post by **steptoe** » Wed Nov 19, 2014 6:44 am

you mean you cannot use any of the previous radiators to bodgey up, just so we can see a newtube of Tweety ??Before the Porsche one comes along .....

Tweety · Post by **Tweety** » Wed Nov 19, 2014 1:12 pm

Nah, it wont be a 2015 engine then eh?

I'd have to connect the thermo fans also and buy some 30mm radiator hose etc. I'll just stare at it for a few weeks.

steptoe · Post by **steptoe** » Thu Nov 20, 2014 9:11 pm

would not hurt to do a compression test on it now eh ??

I'd like to know - for one

I am a little cross x to find turbo like compressions coming out of my full build EA81 - may as well put a turbo on it, but the 30 psi difference across may kill it sooner than I would normally

130 - 160 psi only 40,000km

Subydoug · Post by **Subydoug** » Thu Nov 20, 2014 10:41 pm

Looks good Tweety, Fingers crossed for you.

Jonno, if you have the ea81 service manual, chapter 3, page 31. Has a cyl compression vs rpm chart. STD comp pressure is 149psi@250rpm-156psi@350rpm. Limit is 121psi@250rpm. My car with a CR of ~9.3 cranking at about 250-280rpm gives about 160psi. So Tweety you should be around the 160psi mark or higher as my starter motor is a little bit crap.

Regards

Doug

steptoe · Post by **steptoe** » Fri Nov 21, 2014 6:35 am

Technical Doug to the rescue (I hope) taking the panic out by checking rpms may help - thanks

Just comparing to clapped out old EA81's with way higher readings cranked over possibly at different speeds ?

Subydoug · Post by **Subydoug** » Fri Nov 21, 2014 8:44 am

Possibly Jonno. I was surprised to see my engine only turned over at that low rpm. I do run a pretty small battery though. You said in a different thread that you had differences between cyl's though which is a bad sign

. I would pop the rocker covers off and check your tappets and try again, wide open throttle during cranking. If it still looks low get a syringe and squirt a few cc's of oil down the plug hole and try again. If it only goes up a little bit (like 5 psi) its most likely a problem with valves or headgasket. If it goes up a significant amount (20psi or so) your probably looking at bore and rings. Differences between cylinders....well do the test above first but in general large differences between cyls isnt a good sign. I measured the volume of my combustion chambers with a pipette tube after shaping them and dremeled out the lower ones a bit until they were all within a cc of each other. Comp test back then was a few psi spread between all the cyl's.

Sorry for jibber jabbering in your thread Tweety. There is actually some really good reading in the ea81 service manual, found myself just reading it for kicks lately

. Well worth a look, its a download somewhere on this forum.

Regards

Doug

Tweety · Post by **Tweety** » Fri Nov 21, 2014 8:00 pm

Not a problem Doug.

When I suggested to my eB that I get the engine balanced he was real keen, said the areo ea81's he'd done a few years back ran much smoother when balanced. I know this is obvious but maybe it is more "essential" than merely an extra option?

Re: comp test. In my case wouldnt it be better to run it in first before a comp test? eg get those rings "bedded in" as they say?

Besides if I turn the engine over even though I'm not starting it.....it might qualify for a 2014 recycled engine instead of 2105 as Jonno reminds me of....

Subydoug · Post by **Subydoug** » Fri Nov 21, 2014 10:07 pm

Yeah mate I wouldnt bother doing anything until you have a few hungy km's on it. Even then, your EB sounds like he went to town to give you the best he could so comp checks probably wont be needed unless your curious.

In other news Tweety, I recently got my ea81 running with wasted spark and a 36-1 trigger wheel on the crank. Fully programmable ignition. I mocked up the timing table from the curves shown in the ea81 WSM and its running like a champ. Deffinately feels if anything slightly smoother at the top end, gives the impression that I got another 1k of rpm in the pocket. I will probably get it on a dyno soon, so for sh1ts and giggles Il run both the disty and the wasted spark map and see if there are any notable improvements to be had. The actual install of the hardware on the engine was pretty simple. Could be a nice way to get a little bit more out of your new engine at a reasonable cost, really take advantage of the extra torque down low. Or it could be a gigantic waste of time but let me test that for you

.

Regards

Doug

steptoe · Post by **steptoe** » Fri Nov 21, 2014 10:14 pm

pinches self to find a lad can build efi on EA81

Me thinking as I add in Tonys thread, yeah, valves must be tight on the 130 side.

Thinking it all happened about same time as I fitted up EA82 Y pipe, can alter mixtures, and temps, maybe hotting up the ex valve, asking too much of my 4 thou hot setting.

Fitted new sp plugs BP7ES, 7 for LPG and ran stronger until heat soak set in 16kms later - lumpy idle @91 C when temp alert goes off. There is a pattern. Investigating tomorrow - cold set first to 6 and 8 as cam maker specifies.

Rest Tweety until Feb...or, we do some, is it cloud funding, or crowd funding ..? to see it happen earlier !!??

Tweety · Post by **Tweety** » Fri Nov 21, 2014 10:18 pm

Hi Doug

I have absolutely no idea what you are talking about.
But I read with interest. lol

I assume that "wasted spark" logically means there is some degree of spark that doesnt do any positive things for the engine output.

Pauline Hanson- "please explain"

:p:p:p

Tony

Subydoug · Post by **Subydoug** » Fri Nov 21, 2014 11:26 pm

Wasted spark. No distributor, no rotor button, no cap. Two coils that alternate. One coil fires plugs 1 and 2, then the other fires both 3 and 4. Its called wasted spark because every time the coil fires, one plug arks in a cylinder that doesnt need it, and is wasted.

Advantages besides being able to map the ignition curve. Because there are 2 coils instead of one, the time between the individual coils firing is doubled. Not too much of a problem on our low revving ea's but on screamers it can be hard to get sufficient dwell times. Other major advantage is no mechanical parts. No rotor and cap to wear out. Less maintenance and if you dont just make up a beefy bracket and slap it right in the middle of your engine bay, it can be a lot neater then a traditional coil.

Il post up more when I have it all dyno'd. A distributor isnt going to stop your engine from being awesome.

Regards

Doug

steptoe · Post by **steptoe** » Sat Nov 22, 2014 9:19 am

Good compression is gonna make my beast roar again. thread stealer, adjusted tappets cold, 6 thou ins, 8 thou ex - now got 165 cold cranking pressures all around. Test drive coomin' up

Don't use any sealant goo on rocker covers Tony, seal OK without, and less mess to do tappets again later.

Did I miss your tappet specs set ?

Tweety · Post by **Tweety** » Sat Nov 22, 2014 2:12 pm

Jonno,

Thread stealing is fine by me. ha.

I will assume safely my tappets gap is the stock 10/14 thou. Dont know if eB used sealer on rocker covers but yes, realsie it is not needed although I have in the past used it on the rocker cover only and got many uses form the gasket staying there.

So your comp ratios are fine. (sigh of relief eh) Now, beg to ask here, but your previous posts were (if I recall correctly) 4 thou hot on all. Maybe you went too small a gap?
I've always thought that going down to 8/12 or maybe 8/10 was low enough without risk of trouble????? and getting rid of any tappet noises at the same time. I'll leave them as they are for 1000 kms and check em.

My EB did tell me that retensioning the head bolts is not needed.

By the way guys. My EB was Campbell from Benalla Engine reconditioners. Think his experience on aero and car eA81's speaks for itself.

Doug- that wasted spark idea is interesting. with my severe lack of knowledge on the workings of engines....lol. Will keep an eye on that.

steptoe · Post by **steptoe** » Sat Nov 22, 2014 9:41 pm

Well, the stock Gregories gaps were chaff cutter loud, so refined it to the 4 thou HOT, and that is run to fans on I think, switch off, race under, adjust, and back to heat up for other bank. I should have given more to exhausts but ran that on my 16/56 cam maybe 150,000km just fine. But, it never got an EA82 Y pipe. Thinking 4 thou hot may have cooled down to greater gap on exhaust anyway ??

Even compressions now, but would have been happier to see better than that on my other EA81s and 2's in the 180, 190 region. Hauling Brumby arse now anyway

Cam tag actually has IN .006" and EX .008" hand written on it. Must have missed that detail on initial build