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Discussion Starter · #603 ·
I need to stop trying to read things on my phone.
I've noticed the site isn't very mobile-friendly and requires a larger screen. Between the upper banner and the keyboard popping up you're pretty much blind when trying to reply. Takes me about 3x as long to navigate and make a post! o_O
 

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Discussion Starter · #604 ·
I was at the local you-pull-it yard and found this cool chrome license plate bracket. I also ditched the license plate mounted backup camera for a more discrete camera that doesn't block the license plate light. That's all I've got for you guys this week :ROFLMAO:
 

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Racecars dont need back up cameras haha
 

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Discussion Starter · #606 ·
Racecars dont need back up cameras haha
So you'll throw an unnecessary parachute on your 3G but won't install a $10 backup camera? It's not even a pound between the camera and wiring. And maybe 10% of the driving my car sees is track related so it'd be impractical and make the car unenjoyable to drive if I gutted it... Like too loud to talk, too bouncy, no heat, no ac, no radio, no sunroof, no passenger seat, etc. I'm trying to gap people while riding in style and comfort :LOL:
 

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Discussion Starter · #607 ·
I measured my cams to find the intake and exhaust centerlines and then compared those centerlines to the TDC of both cylinders 1 and 2 to see if the combustion cycle is identical between both banks. I found the timing marks that Mitsubishi places on the valve covers are staggered and cause bank 1 to fire around 24 degrees later in the cycle than bank 2. It turns out some manufacturers stagger cams to create a broader power range on engines without variable valve timing. Since I have custom cams, I wasn't sent a "cam card" to degree them to specific numbers and will have to play around with them and find what produces the most power. Just setting the rear bank timing identical to the front gave the engine a very unique exhaust tone, it builds more vacuum at idle, it turns over a lot easier by hand, it revs quite a bit faster, and it gets the turbo spooling quicker than I've ever seen with any of the turbos I've used. Who knows the gains I can pull out of it with a few more tweaks of the cam timing!

In order to degree the cams I had to pull the spark plugs and I noticed the insulator of the cylinder 2 plug was brown from baked on oil. I looked in the intake and exhaust ports of that cylinder and they were both oily as well so I decided to replace all 4 valve stem seals. I started by plugging the oil drains in the head with chunks of paper towel to prevent any lifters, bolts, or valve spring locks from falling into the engine. Then I removed the rocker arms and left the cam installed. I put the piston at BDC and filled the cylinder with a long bungee cord before bringing the piston up until it pushed against the valves. My valve spring compressor bolts onto the head so it's as simple as prying down on the spring and grabbing the locks with a magnet tool to release them. I replaced the 4 valve stem seals and it seems to have helped but I'll need to check out the intake and exhaust ports later on and make sure they've dried up.
 

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I thought everyone knew that the banks were timed differently? It's the same on the 6G72 also and I believe it was Russ way back over a decade ago that stumbled on that and I think he had the same experience you did with cams. I recall a few others over the years including maybe the guy from Minnesota that kind of quit the forums also talking about this and another turbo guy, Pharm maybe too?

I want to say it's for some reasons on the 6G72 but I can't recall what that was right now...maybe to do with idle or timing belt stretch?

Sent from my SM-G892U using Tapatalk
 

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Discussion Starter · #609 ·
I thought everyone knew that the banks were timed differently? It's the same on the 6G72 also and I believe it was Russ way back over a decade ago that stumbled on that and I think he had the same experience you did with cams. I recall a few others over the years including maybe the guy from Minnesota that kind of quit the forums also talking about this and another turbo guy, Pharm maybe too?

I want to say it's for some reasons on the 6G72 but I can't recall what that was right now...maybe to do with idle or timing belt stretch?

Sent from my SM-G892U using Tapatalk
I haven't been around long enough to know Russ and Pharm was already out of the scene when I bought my first 3G. I'll have to do some searching and see how many degrees others found.
 

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We lost a lot of older posts for some reason a while back, or the search doesn't find them. I was looking for something a few months ago and I couldn't find it. Might have just been an off topic thing though.

The important thing is you found this and it'll only get better.

Found one!


Also found some interesting info about staggering intake valves in a 4 valve head for better flow without loosing low rpm performance, open the valves more but open one a little sooner and you mitigate the low rpm velocity losses by having really big opening. I think. It's s bit over my head. Google staggered intake valves and I'm sure you'll find more.
 

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Discussion Starter · #611 · (Edited)
I've been driving the car on and off for the past few weeks and noticed it's been a bit sluggish on the top end. I did more research on degreeing cams and decided retarding the cams would be the best place to start since I have no other reference or cam card to go off of. I started with 4 degrees and the top end gains were unreal... this thing WOKE UP! Another 2 degrees and it's easily making more power on 18psi of boost than it did on 30psi! It also developed a choppy lope at idle that sounds great :geek:

The car has had intermittent misfires while cruising with higher engine load since I matched the rear cam to the front. After looking over the ignition system I found the distributor rotor is very far off from lining up with the posts in the distributor cap when firing. This causes the rotor to burn on the trailing corner rather than firing from the center of the rotor. The only real way I found to fix this is indexing the distributor, but because the left ear of it isn't slotted it can't rotate. I removed the distributor and pulled it apart before slotting the ear. I'd guess there's 15 degrees it can be advanced or retarded now. I advanced the distributor as much as possible and will know if it corrected the issue when the roads clear again and the 3G can leave the garage!



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I've been driving the car on and off for the past few weeks and noticed it's been a bit sluggish on the top end. I did more research on degreeing cams and decided retarding the cams would be the best place to start since I have no other reference or cam card to go off of. I started with 4 degrees and the top end gains were unreal... this thing WOKE UP! Another 2 degrees and it's easily making more power on 18psi of boost than it did on 30psi! It also developed a choppy lope at idle that sounds great :geek:

The car has had intermittent misfires while cruising with higher engine load since I matched the rear cam to the front. After looking over the ignition system I found the distributor rotor is very far off from lining up with the posts in the distributor cap when firing. This causes the rotor to burn on the trailing corner rather than firing from the center of the rotor. The only real way I found to fix this is indexing the distributor, but because the left ear of it isn't slotted it can't rotate. I removed the distributor and pulled it apart before slotting the ear. I'd guess there's 15 degrees it can be advanced or retarded now. I advanced the distributor as much as possible and will know if it corrected the issue when the roads clear again and the 3G can leave the garage!



Before:


After:
Looking good bro.
 

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Pretty soon you'll be snapping axles or spinning tires on the wheel bead. Can't wait to see a dyno plot with those cams and the tuning that's gone into them, should be pretty badass.

Too bad coil on plug or coil packs aren't a simple option here, but the distributor isn't such a hindrance yet. You'd be looking a an engine standalone and then either running the stock ECM as a trans controller piggyback or getting a standalone trans controller too.

I'm kind of in the same pickle with my Celica as far as tuning, except the Toyota ECM is locked and encrypted with no possibly way around it. I'd have to use it like a trans controller and feed it pass through data or something from a standalone engine computer. It gets messy real fast doesn't it?
 

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Discussion Starter · #616 ·
Pretty soon you'll be snapping axles or spinning tires on the wheel bead. Can't wait to see a dyno plot with those cams and the tuning that's gone into them, should be pretty badass.

Too bad coil on plug or coil packs aren't a simple option here, but the distributor isn't such a hindrance yet. You'd be looking a an engine standalone and then either running the stock ECM as a trans controller piggyback or getting a standalone trans controller too.

I'm kind of in the same pickle with my Celica as far as tuning, except the Toyota ECM is locked and encrypted with no possibly way around it. I'd have to use it like a trans controller and feed it pass through data or something from a standalone engine computer. It gets messy real fast doesn't it?
I'm excited to see the results of the new turbo piping/turbo components, higher compression, and these cams. And yeah it seems like there just aren't a lot of good solutions to removing the distributor. Either a standalone or an external ignition module that can drive the coils and uses a separate sensor/reluctor.
 

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Looking good bro.
That's how the old distributors were use for to advance or retarded base timing. The ECU supposes to advanced timing if the barometer detects if the vehicle is in higher attitudes but it's always good to adjust base timing.
 

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That's how the old distributors were use for to advance or retarded base timing. The ECU supposes to advanced timing if the barometer detects if the vehicle is in higher attitudes but it's always good to adjust base timing.
Even with ECM controlled timing the cam crank correlation has to be matched. When he indexed the cams that correlation was lost. This is more like indexing the distributor on a later model Chevy 4.3 or 5.7 with electronic ignition and a distributor. Actually it's exactly like that.

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Discussion Starter · #620 · (Edited)
Even with ECM controlled timing the cam crank correlation has to be matched. When he indexed the cams that correlation was lost. This is more like indexing the distributor on a later model Chevy 4.3 or 5.7 with electronic ignition and a distributor. Actually it's exactly like that.

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Something I found interesting is no matter how many degrees I retard or advance the distributor, the ecu still fires at the correct timing according to the timing light. Changing mechanical timing with the rear cam or distributor has no effect on the ignition timing, but indexing the distributor to match the rear cam DOES fix the rotor and cap alignment issue.

Also the MSD ignition setup causes a delay in the ignition timing. For example when the ecu was displaying idle ignition timing at 12 degrees the timing light was showing 2 degrees BTDC. 10 degrees is a pretty large delay and is something I'll have to account for the next time I tune it.
 
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