Mitsubishi Eclipse 3G Club banner

461 - 480 of 487 Posts

·
Premium Member
Joined
·
376 Posts
Copy cat ;)

haha jk they look good!! I am waiting for some exhaust stuff to finish up my downpipe, dont mind the mess lol
42818
 

·
Registered
Joined
·
380 Posts
Discussion Starter #463 (Edited)
I've been trying to figure out what piston relief depth is needed for my Web Cams cams and decided the best way to check is to install them. I started with a single exhaust valve to keep potential bent valves to a minimum. Then went on to the low intake lobes and mivec lobe. Each test I changed the cam sprocket advance/retard from -12 to +10. To my surprise there was no contact! This saves me from piston machining, balancing, rod and main bearings, piston rings, engine gaskets, etc.
 

·
Registered
Joined
·
380 Posts
Discussion Starter #465
How are you checking it?
A borescope and rotating the engine very slowly. The fact that I can move the gear over 10 degrees in both directions without interference gives me assurance that at higher rpms, where valve control becomes sloppier, the engine will stay happy and not crunch valves. If that were to happen, it'd guarantee the new heads will be installed this year :LOL:
 

·
Moderator
Joined
·
54,348 Posts
A borescope and rotating the engine very slowly. The fact that I can move the gear over 10 degrees in both directions without interference gives me assurance that at higher rpms, where valve control becomes sloppier, the engine will stay happy and not crunch valves. If that were to happen, it'd guarantee the new heads will be installed this year :LOL:
Lumps of clay work well too, but then you gotta bolt it all together and apart repeatedly.
 

·
Registered
Joined
·
380 Posts
Discussion Starter #467
Lumps of clay work well too, but then you gotta bolt it all together and apart repeatedly.
I don't plan to crack open the engine quite yet. The engine spun over with no interference but if I bend some valves on the first fire up then so be it.The current heads can be my sacrificial lamb to the car gods :ROFLMAO: When running I can disable my rpm window switch and manually enable mivec to test that all profiles have clearance.
 

·
Premium Member
Joined
·
376 Posts
Oh yes I forgot how did you test the high lobes!!
 

·
Moderator
Joined
·
54,348 Posts
I don't plan to crack open the engine quite yet. The engine spun over with no interference but if I bend some valves on the first fire up then so be it.The current heads can be my sacrificial lamb to the car gods :ROFLMAO: When running I can disable my rpm window switch and manually enable mivec to test that all profiles have clearance.
You know, you gave me an idea! Put some candle wax on the piston top, turn the engine over, then look in with the scope for damage to the wax. When you run the engine the wax should just melt/burn off. Doesn't help for the high lift lobes I guess, unless you can pop them on with some air pressure I guess or just put the pistons at TDC one by one then manually push the valve down?
 

·
Registered
Joined
·
380 Posts
Discussion Starter #470
Oh yes I forgot how did you test the high lobes!!
I used a bolt across the Mivec rocker arm to have it always engaged. I'll try to get a picture to upload.

You know, you gave me an idea! Put some candle wax on the piston top, turn the engine over, then look in with the scope for damage to the wax. When you run the engine the wax should just melt/burn off. Doesn't help for the high lift lobes I guess, unless you can pop them on with some air pressure I guess or just put the pistons at TDC one by one then manually push the valve down?
My only concern would be having wax run onto the rings. With the borescope the valves appeared to have quite a bit of room as the piston neared the top of the stroke (maybe a little less than 1/4"). I'm confident I could run the stock head gaskets (24 thousandths thinner) and still be fine. That would save me nearly $200 every time the heads come off and bump compression (y)
 

·
Moderator
Joined
·
54,348 Posts
I used a bolt across the Mivec rocker arm to have it always engaged. I'll try to get a picture to upload.


My only concern would be having wax run onto the rings. With the borescope the valves appeared to have quite a bit of room as the piston neared the top of the stroke (maybe a little less than 1/4"). I'm confident I could run the stock head gaskets (24 thousandths thinner) and still be fine. That would save me nearly $200 every time the heads come off and bump compression (y)
That's a ton of room if it's that much. Things tend to look a little distorted on those ebay/amazon butt-cams. I know the one I use at work is great but take the apparent distances with a grain of salt. It's always better to know more exactly. Just read about using feeler gauges between the valve and rocker or the cam lobe and follower (and then some math) to figure how much clearance there is. You always need more than you think because things get hot and expand and also stretch under load too.

Wax in the rings would just melt and flow out, liquid paraffin will flow right out like water at engine temp and dissolve into the engine oil. Paraffin is one of the components of engine oil, or used to be, so it'll be harmless.

So back in the day when I was shaving the head down on an old single cyl engine I used modeling clay to check clearances, wanted a little more compression out of it since it was electric start anyway. That worked well, but yeah pulling the head off and putting it back on each time to check was a pain.
 

·
Registered
Joined
·
380 Posts
Discussion Starter #472
Using my overhead valve spring compressor I can further compress a valve when it's at full lift to see the clearance. I will have to check that for peace of mind.
 

·
Registered
Joined
·
380 Posts
Discussion Starter #473
I bought Fidanza adjustable cam gears and I noticed they put the TDC timing mark between the teeth rather than on a tooth. I stacked the gears and lined up the dowel pins/teeth to determine the actual TDC location. With the Fidanza TDC mark half a tooth back from the valve cover mark (still at 0 degrees on the gear) the cam is in time. I'll be calling Fidanza to see if they've corrected this and can send a replacement set. Last thing I want is to bend valves cause I read the gears incorrectly!

Yesterday I pulled the original Mivec heads to install the new "head lift fix" heads. These new heads also have a lot more material in the ports and should stand up to heat better. A friend convinced me to oring the block so I will likely do that while I'm in there.

Lastly I managed to get the interior completely back together. The backup camera now functions when the car is in reverse and the line out converter is wired in to send the rca's and amp-on signals to my small amp/sub combo.
 

·
Moderator
Joined
·
974 Posts
Are you still running the "Kicker 500.1 amplifier" and "Sundown SA-8v2 subwoofer" or do you have a different unit now? Looking for a small combo unit for my car just to fill out the bottom end a little without taking up a lot of space in the trunk. Nothing crazy loud. The system is already pretty balanced.
 

·
Registered
Joined
·
380 Posts
Discussion Starter #475
Are you still running the "Kicker 500.1 amplifier" and "Sundown SA-8v2 subwoofer" or do you have a different unit now? Looking for a small combo unit for my car just to fill out the bottom end a little without taking up a lot of space in the trunk. Nothing crazy loud. The system is already pretty balanced.
Yeah still running that combo. It sounds awesome and plenty loud. I believe I have a 1.25 cu ft ported box so lots of room still in the trunk.
 

·
Registered
Joined
·
380 Posts
Discussion Starter #476
I will have my new heads installed by the end of this weekend 👍

Compressing the springs and transferring everything over except for the valves


New viton valve stem seals installed and transferring the insert washers


New lifters taking a bath before installation 🛁


I'll post pics after the heads are installed if I survive torquing to 120ft-lbs. Stay tuned
 

·
Registered
Joined
·
380 Posts
Discussion Starter #477 (Edited)
The plan to install both heads hit a speed bump but when doesn't that happen? :rolleyes: there ended being 11 of the 16 insert washers stuck in the heads and I had no way to tap them out. I ended up making a slide hammer attachment that was small enough to hook under the inner lip and pull them all out! One head is completely ready to go now.

 

·
Registered
Joined
·
380 Posts
Discussion Starter #478
Both of the heads are done and ready to drop in but I've decided to go "all out" and o-ring the block. I have the tool... now I just need to find time to do it AFTER I've finished the house projects and everyone else's projects I've taken on :rolleyes: pics will be posted of the o-ring process
 

·
Registered
Joined
·
380 Posts
Discussion Starter #480
Why not a cut ring head gasket?
Because that doesn't exist for any of the 6G7x engines, especially with a 1mm overbore like I have. Also you don't want something that cuts into the already thin/weak head deck.
 
461 - 480 of 487 Posts
Top