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FJ1600 Question

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If your ports are restrictive you might actually want more duration.  Have you contacted anyone with experience grinding cams for EA engines?  I think Delta cams specializes in grinding Subaru cams, they might have a good idea what you want.

Also, if you can drive it so you can at least keep the RPMs over 3000 (preferably 4000) while climbing, it doesn't matter much what it does at low RPM.

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Hi Guys, things are progressing well, I have all of my major parts machined, and have the bottom end together. The heads received a huge haircut of 0.071” to achieve a chamber capacity of 30cc. This will give me a 10.8:1 compression ratio. The cam is a little more sensible with 230 degrees duration. I have had to trim and re-profile the valve guides as my new spring retainers are different to the ones I initially measured the clearance with. I also decided to run an exhaust valve stem seal as the original EA engines did not have these. I have had to use a seal which is shorter than the Subaru ones to allow clearance for the valve lift I have. My new valve springs are a beehive style of spring with 10 degree retainers and locks. Spring pads have also been re-machined to suit the springs.

I’ve dummy assembled the heads to the block to check pushrod length and rocker geometry and I now know what push rod length I need, but all the shops are closed for Christmas, so I’ll order them as soon as I can. In the process of checking the rocker geometry I realised that the rocker posts were not positively located by any means other than the clamp pressure of the head bolt so I made some hollow stainless steel dowels to locate them. This allowed me to check the alignment of the rockers on the valve tips. Most rockers were in the ballpark but there were a couple that I wanted to move so that the valve has contact in the middle of the rocker pad. This led me to some research online and I came across plenty of information about VW rocker shaft assemblies, which are very similar to the Subaru ones. There are several aftermarket versions available.

All of the aftermarket assemblies are made to eliminate the wavy washers and spring clips used on the OEM versions. They instead, precisely shim the rockers and use thick washers and bolts in the end of the rocker shafts to eliminate the spring clips, or (circlips in Subaru case). I have used this information to modify my own assemblies to eliminate any possible failures. The rocker shafts were drilled and tapped each end. I used M6 countersunk screws in one end of the shafts because there is not much room inside the valve cover and M8 at the other, as this is where most of the load comes from the pushrods. The end caps are recessed onto the ends of the shafts to locate them and to eliminate some shims. A potential side benefit is that the rockers might be a lot less noisy than the standard setup. A lot more work but I think this will be very much worth it.

I had to make an ignition timing scale bracket, as the original marks had been removed from the flywheel in the process of lightening. A simple bracket was made using a right angle section of aluminium, bolted to the front of the engine near the crankshaft pulley.

After modifying the rocker assemblies I realised that there is even less room now than there was under the rockers to tension the head bolts. I had previously machined a socket to fit the head bolts under the rockers but now with more stud poking out, this socket is useless so I have made a tool, which will allow me to tension the bolts with the rockers installed.

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Rocker End Caps.JPG

Timing Scale1.JPG

Clutch Install1.JPG

Head Bolt Tool1.JPG

Head Bolt Tool2.JPG

Timing Scale2.JPG

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G'day All,

With the engine now finished, it is time to take the bodywork off the car again for fitting the engine. Due to having to take so much off the heads and block, my twin carb manifold does not fit anymore, so I have had to fast track the Weber manifold, which also meant that I had to finish the remote thermostat housing and related plumbing. Radiators were plumbed in and the wiring finalized. Only thing left to do is fill it with fluids and fire it up.:banana:

Eng Comp.JPG

Car Strp.JPG

Thrm Hsg.JPG

Carb Mock.JPG

Therm Plumb.JPG

Carb On.JPG

Inst2.JPG

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Looks great!

Did you fire it up?

How do you get the engine and fuel cell in?  Slide in fuel cell and then engine from the side and then put on the carb, etc?

Are the rear CV axles at a huge angle?

You should weigh it when it's all assembled and running.

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Thanks Guys, it's finally coming together after all these years.

There is a removable triangular bar on the left side, which allows you to get the engine in sideways. Carb, dizzy and everything else has to be installed when the engine is in the car. It's not the easiest thing to work on, it just takes patience. Fuel cell is installed after engine.

The CV's are at a huge angle unfortunately, but that's the way the car was designed and it would be a huge job to change. Maybe in the future if the CV's don't last long.

I will definitely be weighing it when finished as I need to set the individual corner weights anyway.

I have fired it up, fixed a few leaks and adjusted the timing. The carb is very rich still and sounds a bit fluffy on acceleration. I'm ordering a jet kit tomorrow.

I'd post some video, but they are too big a file to post here. Could you suggest an alternative?

Astro

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6 hours ago, Astro12 said:

Thanks Guys, it's finally coming together after all these years.

There is a removable triangular bar on the left side, which allows you to get the engine in sideways. Carb, dizzy and everything else has to be installed when the engine is in the car. It's not the easiest thing to work on, it just takes patience. Fuel cell is installed after engine.

The CV's are at a huge angle unfortunately, but that's the way the car was designed and it would be a huge job to change. Maybe in the future if the CV's don't last long.

I will definitely be weighing it when finished as I need to set the individual corner weights anyway.

I have fired it up, fixed a few leaks and adjusted the timing. The carb is very rich still and sounds a bit fluffy on acceleration. I'm ordering a jet kit tomorrow.

I'd post some video, but they are too big a file to post here. Could you suggest an alternative?

Astro

After all that engine work you should really get it on a dyno sometime to fine tune the jetting and timing.  Might as well get it running as best you can by feel first.

If it's just a matter of not being able to post it on the forum, I'd put it on youtube.  Then you only have to upload it once and can share it anywhere.  If it's too big to upload in general you can edit it shorter and/or reduce the resolution.

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Hi Guys, the car is finally all together and been inspected by CAMS official. Just waiting on my log book now. Need to replace the fuel pump and get it on the dyno for some tuning.

:banana:

Finished Car1.JPG

Finished Car2.JPG

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Top effort mate! Were they happy with what they saw? 

Mans was the fuel pump a requirement to a certified one or is it just dead/dying and needing replacement? 

I’m keen to see this thing out and about but am a bit far south to just drop in on an event... 

Cheers 

Bennie

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Bennie, the inspector certainly was happy with what he saw. He even wrote a comment on my application that the car was well constructed and tidy, which he said he doesn't often do but that this car deserved a comment.

The fuel pump in the car seemed to be getting lazy the last few times I've started it. The fuel pressure has dropped. The pump in the car is the original one which would be 20+ years old, so not too surprising. I have the replacement pump already so I will fit on the weekend. Got my log book today in the post.

Bendigo is where I got the car from.

I hope to get to Bathurst at some stage as they run hillclimb events down there so I'll let you know when I'm going.

Astro

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Bendigo eh? I missed that detail if it was shared. 

I’m yet to visit Bathurst and “do a lap”.  Keep me posted and we’ll see what we can do ;) 

And top effort on the inspector’s remark. That must’ve been a good feeling! 

So now the log book is in, what’s the first event? 

Cheers 

 Bennie

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Had my first outing with the car at a hillclimb event. Went OK but there are some things I need to change and the engine was a bit on the rich side.:)

SK 94 @ Grafton 2019 Rd5 Hillclimb Champs1.jpg

SK 94 @ Grafton 2019 Rd5 Hillclimb Champs5.jpg

SK 94 @ Grafton 2019 Rd5 Hillclimb Champs4.jpg

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Anything good to report? 

Pics were awesome, “report” was a bit “meh, it goes” :( 

Cheers 

Bennie

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Hi Guys, sorry about the long gap in posts. I’ve not had too much to report.

My first outing in the car was a bit disappointing really. I turned up to a state championship hillclimb round on a freshly laid surface with 20 year old slicks. I arrived at the track on Friday to setup and Saturday (practice) rained for most of the day so I put the car away after lunch as the track did not even look like drying out. No open wheelers ran in practice but all the sedans were out in the rain and actually doing good times.

Sunday dawned quite foggy but no rain yet. By the time drivers briefing was over it was clear that the rain had finally gone away. The track was still wet in most places by the time competition got underway. My first run was way cautious, having never driven the car at all. The track seemed very greasy but I’m sure it was my vintage slicks providing the lack of feel. One other feature of the car which wasn’t helping was the fact that the car is so stiffly sprung that it was picking up a wheel whenever the road twisted, which this circuit does lots over the course of a lap. An open diff also wasn’t helping the situation at all. The engine ran ok, but just didn’t seem happy at times, backfiring through the carb occasionally. I completed all my runs, getting a little bit more game than the run before, and I was just happy getting the car home in one piece.

Since that first outing I have had other things taking up my time and money, but I have managed to get the car on a dyno for some tuning and it seems that the original jetting which I had in the car was very close and the only thing which really changed was reduced ignition timing!! I was originally running 15 initial and 35deg total and now it’s at 8 initial and 28 total. I know this will reduce power but the dyno guy reckons 98 octane can only handle 30 total usually. I didn’t have the right jets to do any further tweaking that day so I’ve got some on the way and maybe I can sneak up the timing a little once I have them fitted. So the engine made 90 rwhp, which is certainly not awesome, but just happy that the engine now runs cleanly to 6000rpm. Also discovered that my digital dash tach isn’t working properly and now just relying on a shift light set at 5500.

I’m hoping to get the car to a practice day at a circuit more suited to it’s setup in a couple of weeks, where I can do multiple laps in a session to get a bit of a feel for the car. I have to do some more running in this car before the big man in the red suit comes down the chimney!! 

Astro

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90 whp out of an EA81 is still pretty damn good!  If a big valve made 84 chp and you figure in driveline losses a stock EA81 is putting out 63-71 whp.  Given the breathing issues these engines have I'd say you're doing well, with some room still to grow that output!

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Hi Guys I've finally had the car out at a circuit to do some laps and get used to it. The car felt quite fast, but probably just because I'm not used to it yet. I got about 8 laps in and was starting to really enjoy the ride, pushing a little more each lap,but when I came into the pits the car was making a hell of a racket from the transmission area. I inspected it as best I could, but could not see what the problem was. I figured it was in the transmission and I wasn't about to split the transmission at the track, so I packed up for the 3hr trip home. A bit of a disappointment but that's what happens sometimes when you play with cars.

When I got the car home I pulled the car apart and discovered that the  flywheel had come loose!!  I used RTV to seal the flywheel bolts and torqued them to spec, as they go through the crank flange into the crankcase. Big Mistake. I should have used Loctite. 

That was only the start of my dilemma, as now the original flywheel bolts were a little bit worse for wear and one had broken off. Originally I thought that the bolts were M9 x 1. Stupid size to make a critical fastener I thought, but no, it gets worse. I have a spare EA 81 engine which had a set of flywheel bolts in it, so I pulled them out and tried fitting them. They are too big. They are actually M9 x 1 but the bolts that came out of the EA 71 crank are about 0.5mm smaller in diameter. Really!!!...…. Mr Subaru, M8.5 x 1!!!! I cant even buy M9 bolts. I'm also having trouble getting an M9 tap. There's not really enough meat in the flywheel flange for M10, for which I could buy decent ARP bolts. So I'm going to continue looking for an M9 tap so I can use the EA 81 bolts. I remember someone saying that Subaru engines are like Lego, ie, you can mix and match parts. From my experience with these engines I find that very far from the truth.

Hopefully I can update soon with a bit more of a positive story. 

 

Morgan Park Oct 2019.2.JPG

Trans Split1.JPG

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