A Bad Day In CA18DET Land

Discuss topics related to the CA18DE and CA18DET series engines.
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Re: A Bad Day In CA18DET Land

Postby float_6969 » Mon Jun 13, 2016 5:15 am

Buddyworm wrote:Might still have a hard time keeping it from creeping. With externally gated manifolds it's usually a good bet that the WG pipe doesn't have an "ideal" flow path for boost control. Could have the bulk of your exhaust flow blasting right past the wastegate.
Image
It sets exactly opposite of the turbo flange. This is kind of an odd manifold in that it's a divided manifold, but it is NOT equal length. It's a sort of log/divided mixture. The exhaust runners are about as short as they can get, especially #3. I think it's MAYBE 3" long. They also feed into a "plenum" of sorts for each side of the turbine housing, and as such, don't feed into the turbo at an ideal angle. I think HKS's thinking in this was that it was more of a pressure manifold and less for flow. I'm sure given their turbo options at the time, decreasing spool RPM was the highest priority, and so sacrifices were made in regards to ultimate flow. In that regard, if you look closely at the picture, you can see the wastegate flange is exactly opposite of the turbine flange, both of which feed off of the "plenum". Since advancing the timing, I haven't seen more than 8psi, which I think is in the acceptable range. I'm also pretty sure I'm still way off from the ideal ignition timing. And even if it does creep to 8 or 9 psi, I have no intention of ever running it that low once I'm done tuning those ranges of the map, so I suspect any creep issues will be gone once I get the 14psi spring in it.
Buddyworm wrote:It does depend on how far off you are from MBT though...
I think i'm way off from it. E85 likes lots of timing advance due to it's slow burn rate. All I did with the timing was ramp it up from the idle timing of 25°to 40°by 3000rpm. From there, it's just fixed at 40° regardless of RPM or boost. The slight creep I was seeing I'm sure was from the lack of advance I have at the higher RPM's as I know from experience (and as other's have said on the internet) that the timing needs to start to be advanced once you get up in the RPM's or you start to get away from MBT.
Buddyworm wrote:If I had to put a (very) rough number on it I'd say 5-6deg or so retarded from MBT is when you start to put enough extra energy through the turbine to get an increase in wheel speed/boost pressure.
You may be right. I haven't spent enough time on a dyno to know what it's going to like.


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Re: A Bad Day In CA18DET Land

Postby Buddyworm » Mon Jun 13, 2016 11:18 am

float_6969 wrote:
Buddyworm wrote:Might still have a hard time keeping it from creeping. With externally gated manifolds it's usually a good bet that the WG pipe doesn't have an "ideal" flow path for boost control. Could have the bulk of your exhaust flow blasting right past the wastegate.
Image
It sets exactly opposite of the turbo flange. This is kind of an odd manifold in that it's a divided manifold, but it is NOT equal length. It's a sort of log/divided mixture. The exhaust runners are about as short as they can get, especially #3. I think it's MAYBE 3" long. They also feed into a "plenum" of sorts for each side of the turbine housing, and as such, don't feed into the turbo at an ideal angle. I think HKS's thinking in this was that it was more of a pressure manifold and less for flow. I'm sure given their turbo options at the time, decreasing spool RPM was the highest priority, and so sacrifices were made in regards to ultimate flow. In that regard, if you look closely at the picture, you can see the wastegate flange is exactly opposite of the turbine flange, both of which feed off of the "plenum". Since advancing the timing, I haven't seen more than 8psi, which I think is in the acceptable range. I'm also pretty sure I'm still way off from the ideal ignition timing. And even if it does creep to 8 or 9 psi, I have no intention of ever running it that low once I'm done tuning those ranges of the map, so I suspect any creep issues will be gone once I get the 14psi spring in it.
Lots of good stuff going on with that manifold, but yea, WG position is far from ideal. Will do the trick though!
Buddyworm wrote:It does depend on how far off you are from MBT though...
I think i'm way off from it. E85 likes lots of timing advance due to it's slow burn rate. All I did with the timing was ramp it up from the idle timing of 25°to 40°by 3000rpm. From there, it's just fixed at 40° regardless of RPM or boost. The slight creep I was seeing I'm sure was from the lack of advance I have at the higher RPM's as I know from experience (and as other's have said on the internet) that the timing needs to start to be advanced once you get up in the RPM's or you start to get away from MBT.
Wow! That's a huge amount of advance on boost. Even low boost.

I don't have experience with E85 but 40deg I'd wager puts you well past MBT. I highly doubt it wants that much timing, especially since you're high compression.

Your boost creep lessened when you advanced timing because the combustion process is more complete when your Ex valve opens, keeps more energy in the chamber vs. dumping it out the exhaust valve where it can drive the turbine.

I doubt those excess degrees are producing additional torque though. More than likely you're just putting more heat into the metal parts and cooling system. You might even pick up power if you take some timing out.

You're better off dealing with boost creep vs. overadvanced timing if you ask me. The e85 will keep combustion under control and away from knock and let you get away with all sorts of crazy timing advance, but too much timing can lead to preignition, which is worse.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Mon Jun 13, 2016 11:27 am

On gasoline it ran 15 deg at idle. On E85, it would barely even idle at 15 deg. It actually had the best idle at 30 deg, but I like to keep my idle timing just back from ideal, so that as the revs drop, I can add some timing to keep the idle stable.

I'm not high compression anymore. The 84.5 mm pistons with standard dimensions otherwise yield a CR of about 8.7:1. I also have cams, which effect the timing as well. Ultimately it'll end up on the dyno and a timing map based on MBT minus 3deg will be built.

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Re: A Bad Day In CA18DET Land

Postby Buddyworm » Mon Jun 13, 2016 1:20 pm

Definitely makes sense that it wants more timing with the E85, but damn 40deg is a lot lol.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Mon Jun 13, 2016 1:36 pm

I agree, though 25 at idle is a lot as well. We'll see what the dyno says.

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Re: A Bad Day In CA18DET Land

Postby Buddyworm » Tue Jun 14, 2016 9:34 am

What you using for injectors there Float?

The newer Bosch EV14 tech likes higher rail pressures and will produce better atomization at low pulsewidths than the EV1 hardware. Plus smaller lag times at equivalent flow rates :bigthumb: Might help a bit with idle quality.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Tue Jun 14, 2016 10:25 am

Deatchwerks CA specific 1200cc injectors. Idle is OK, though it wanders a bit more then I like, but that's just me being picky. If I didn't have an AFR gauge to see what was happening, I'd think the idle was as good as it can be with an ecu that doesn't have any idle control.

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Re: A Bad Day In CA18DET Land

Postby Buddyworm » Thu Jun 16, 2016 8:13 am

float_6969 wrote:Deatchwerks CA specific 1200cc injectors. Idle is OK, though it wanders a bit more then I like, but that's just me being picky. If I didn't have an AFR gauge to see what was happening, I'd think the idle was as good as it can be with an ecu that doesn't have any idle control.
Good stuff.

An IAC would go a long way to stabilizing idle for sure. :cool: Even though the CA ones suck.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Thu Jun 16, 2016 8:33 am

Idle just varies with load. It's otherwise stable. It's about 1100 with no load, and drops to about 800 with everything on. Idle AFRs vary between a displayed value of 13:1-15:1. It's on E85, so the actual AFRs are more rich than that. I'm really just being picky about the AFR's. These 1200cc injectors on E85 are equivalent to about 700cc injectors on gasoline. That's a pretty damn big injector for a 1.8L. If I didn't have an AFR gauge telling me what was going on, I'd think everything was fine.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Tue Jul 12, 2016 4:24 pm

Still working on street tuning here and there. Just hasn't been much time. I was going to do some tuning on Sunday, but the first time I went to do a pull
to redline, I threw a magnet out of the crankshaft pulley. I ended up having to get the car towed home. Luckily the magnet stuck to the lower timing cover behind the pulley. Apparently I got a bad batch of epoxy because it never set up completely and was still kinda gooey, which is why the magnet came out. So I redid all three magnets and let them set all afternoon to make sure the epoxy set up this time, which it did.

Also, in regards to me saying the AFR's were wandering more than I wanted, I ended up gapping the plugs down just out of curiosity and it seems to have helped a lot. The AFR's are much more stable now and the random mis-fire I was getting at idle has disappeared. I've given up on using the stupid coin gappers, as I think I was gapped over 1.1mm. I gapped them down .8mm.

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Re: A Bad Day In CA18DET Land

Postby RustyAE86 » Fri Jul 15, 2016 6:39 pm

float_6969 wrote: I threw a magnet out of the crankshaft pulley

Forgive me if I missed it, but are you running crank trigger? :confused: The magnets caught me off guard and now I'm really interested in that too

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Sat Jul 16, 2016 5:22 am

The standalone I'm using is made by a company called SDS. I've had it for about 10 years now. I recently upgraded it to the newest version, the EM5-F. SDS stands for Simple Digital Systems. Tuning this system is about as easy and simple as it gets. It also does not require a laptop for tuning. The way it works is very simple. For a 4 cylinder, there are 3 magnets glued into drilled holes in the crank pulley. Two trigger magnets and a sync magnet. Then you have a Hall sensor to detect their rotation. From that the ECU is able to calculate engine speed and when to fire the injectors and the wasted spark coil packs.

At the time that I bought it, it was one of the cheapest standalones and it didn't require a laptop, which I didn't have and would have been an additional expense. I also knew I could only afford to street tune it, so I wanted something simple to tune. Admittedly it's lacking functionality by today's standards, but it's robust, reliable, and still the easiest to tune system on the market.

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Re: A Bad Day In CA18DET Land

Postby boost_boy » Mon Jul 18, 2016 5:35 am

Ahhh yes, the old "Magnet flew out and is now stuck to the timing cover"...lol. Love it. Take it home, clean-up the hole, mix up some more epoxy and stick it back in. I don't miss those days, but it was an adventure that makes you get better over time.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Mon Jul 18, 2016 6:06 am

LOL, yea, it was a first for me. I've installed magnets in probably 5 crank pullies and never had an issue. I know it was that epoxy though. I've never seen it do that before. It was all soft and rubbery. I ended up re-doing all of them because the old epoxy just peeled off. I know it won't happen again though... Plus I took it 8K about a dozen times this weekend tuning it and never had a hiccup. Now if I can just get all these coolant leaks that keep popping up chased down...

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Re: A Bad Day In CA18DET Land

Postby boost_boy » Mon Jul 18, 2016 9:57 am

Well, good you're up and running again. Leaks can be sorted, but when you blow-up a motor, that's just the pits. I'm near completely back up and running both the sentra and the S13, but I have a lot of cleaning to do as those cars have mildew under their hoods, oxidation on those turbocharger housing (what a waste of $$$s), so yeah, I'll be around a lot more moving forward :cool:

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Tue Nov 15, 2016 9:29 pm

13, 15, and 17 psi respectively. Wanted to do more, but the 5psi spring wasn't up to the task. I tried to change it out, but its impossible to get it in when it's on the manifold in the car. So I get to pull the turbo and manifold off to get the spring back in it. Then back to the dyno for more boost.
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Re: A Bad Day In CA18DET Land

Postby float_6969 » Tue Nov 15, 2016 9:30 pm

Oh, and the runs are from 2K, to 8K RPM.

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Re: A Bad Day In CA18DET Land

Postby dash » Wed Nov 16, 2016 12:46 am

could only understand dynos with ft-lbs tq over an rpm scale
can't make out the hp numbers..... is that 315(13), 344(15), 372(17)?
sounds like a beast in the making. 30psi should b nuts. How does it drive?

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Wed Nov 16, 2016 5:49 am

Yea, he tried for a while to get a good tach signal and it just couldn't get one. Without a tach signal, the computer can't calculate torque.

319 @ 13psi, 344 @ 15psi, 372 @ 17psi

Unfortunatly, I didn't get to drive it with the boost turned up. I can't get the wastegate back together with the 15psi spring, so it's just open all the time. I'm going to have to pull the manifold out to get it back together.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Mon Mar 06, 2017 6:52 am

I totally forgot to update this post! I got what I THOUGHT was the correct wastegate spring in there, only to find out it was like a 21 psi spring. Those old HKS wastegates are impossible to get springs for now through HKS. I ended up buying a Chineese copy complete wastegate with a 12 psi spring in it and robbing the spring out of it. Works perfectly now, and no more boost creep issues. Shortly after that I started having fueling issues. It was random though. Eventually the problem got worse and I was able to figure out that the issue was a bad set of injectors. They were new, so I sent them back to Deatchwerks for warranty. During the time I was trying to track down my issue I borrowed a friends set of Injector Dynamics 1000 cc injectors and was AMAZED by them. I ended up buying a set of ID1300's and when I get the DW injectors back, I'm just going to sell them. The way they perform at low pulsewidths is nothing short of amazing. After I got that done, I redesigned my fuel system to a semi-returnless system so that I could pre-heat the fuel during cold starts so the engine wouldn't be so fussy when it gets cold out (below about 35°F, the engine didn't like to stay running unless you just let it idle and warm up). Then I re-did my ignition system. I converted to VAG coils fired in pairs (direct fire, wasted spark). These coils are no joke. I had a 7.5A fuse in my old setup (GM twin-tower coil packs). I've never blown it before. I fired it up with the VAG coils and it blew in a few seconds. I had to put a 10A fuse in it to keep from blowing. I haven't stuck an amp meter on it to see what it's pulling, but it must be between 7.5-10A. Car is running really well. I've been just running wastegate pressure because it's been cold and I had traction issues, but it's starting to warm up again, so I'll see if it stops breaking up around 19psi now (was getting spark blow-out). I still need to get my PCV system sorted out as the valve covers are just blowing into the engine bay and it's stinky. I need to get my EBC hooked up so I can get rid of my cheap-o MBC, I also have a fully electric power steering column that I had built to install so I can ditch my hydraulic power steering setup.

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Re: A Bad Day In CA18DET Land

Postby dash » Mon Mar 06, 2017 1:53 pm

Aren't those sds/GM coils the same as on the buick grand nationals ? street buicks hit hi 500s ft-lbs tq @30+ psi
they send out a long hot white spark. I'm surprised they needed upgrading

which electric power steering u went with ? ....separate ecu controlled ?

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Mon Mar 06, 2017 5:05 pm

Idk if they're the same as what's on the GN's, but they're pretty well known to start to have issues around the 200hp/L mark, which is right where I was out. I gapped the plugs down to .8mm and that stopped it at 19psi, but then I started having part throttle issues where I have it leaned way out for fuel economy. The VAG coils let me open the gap back up to 1.1mm and not break up at 19psi. They must have more power than the GM coils because uthey're pulling way more amps.

There's a thread in the 240sx forum about the power steering. I had it made by zpoweesteering.com. That's a company that AZHitman (the guy that owns NICO) also owns.

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Re: A Bad Day In CA18DET Land

Postby dash » Tue Mar 07, 2017 2:14 am

hmmm, I wonder what coils boost_boy use on his hi output sds/ca18's ?
just noticed several hi strung sds cars not running the GM coils
I remember talking to this guy online, about his 1.6L build way back; http://www.sdsefi.com/features/jan064ag.htm toyota GZE coils

quite a few have 'adapted' other factory electronic power assist columns/ecu to their cars, diy junkyard style
they rave about how they can 'dial in' their steering effort. Suzuki Ignis unit compact, more popular abroad
pretty much like this; https://www.youtube.com/watch?v=uKzCaEjvJeM

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Tue Mar 07, 2017 6:31 am

If you're not concerned about fuel economy, gapping the plugs down will let you continue to use the GM coils at higher power levels. I'm also on E85, which supposedly requires more ignition energy as well. And really, even if you're just running closed loop/near stoichiometric AFR's a tighter gap would probably be fine. I'm running a gasoline equivalent AFR of around 18:1 at cruise loads, so I need as much spark gap as possible to light the mixture. And I'm still not going to be surprised if I end up having to tighten it back down at higher boost levels, but I'm hopeful I don't. I might also change to a different plug design that may help as well, but I'll cross that road when I come to it.

Here's the link to the post about the powersteering; topic612421.html. I'll have the same ability to dial in the steering effort, which I'm excited about. It looks like a similar setup, but the guy has WAY more room to work than we do in S-chassis car's. I had seen similar video's before on these, but they all have miles of steering rod to work with. With tilt wheel, a collapsible steering column, and the way the steering rod enters the steering rack, it was beyond my skill level and the tools I have available to me to be able to install this type of assist in my car. It required some pretty serious fabrication to pull it off.

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Re: A Bad Day In CA18DET Land

Postby boost_boy » Tue Mar 07, 2017 7:59 pm

hmmm, I wonder what coils boost_boy use on his hi output sds/ca18's ?
I actually still use MSD coils which are sitting on top the MSD coil blocks to properly utilize my MSD DIS-2 ignition box. 20 to 30lbs of boost and not an issue. Been behind the scenes for a minute, but I had to come check on float to see what is up to these days :crazy:

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Tue Mar 07, 2017 8:33 pm

Annnd I think the VAG coils are acting up on me. I went for a drive today for about 20 minutes. As I was headed home the car mis-fired once and then seemed fine for about 15 seconds and then just died. I had to let it set and cool down for about a minute and then it fired back up. It ran fine for another few minutes, then mis-fired once, then died about 15 seconds later again. I let it set for a minute and then was able to make it home. I'm pretty sure they just overheated. I have the dwell set at 3.5ms and everything I'm seeing online says they hit max saturation at 3ms. That being said, the only way I was able to get the SDS to trigger them in pairs was to change the trigger output to a 12v signal and they're designed for a 5v signal. If dropping the dwell down to 3ms doesn't solve the issue, I'm probably going to have to give up on them. The SDS ignition trigger circuit is limited to about 30ma @ 5v and the coils are pulling more than that running them in pairs. I could have an external ignitor made that will run them, but I'm kind of getting tired of fighting ignition issues. At this point I'm really wishing I had just bought a DIS-2 and been done with it. It would have been more money than what I've spent on this setup, but I KNOW it would have worked. Outside of the ignition problems, the engine runs great. No smoking or oil consumption. Compression is great. Idle quality is great. Blow-by is lower than any of my other builds. I still get some lifter noise, which is a little annoying, but it's minor and I don't worry about it much.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Sun Mar 12, 2017 7:13 am

Dropped the dwell down the other day. That seemed to have fixed the issue, BUT when I was "testing" it I was getting onto the highway and was beating on it pretty good. Something felt weird so I pulled off. I thought the engine felt a little off, but when I pulled over and got out, I heard the drivers rear tire hissing like MAD. The valve stem had torn and was leaking badly. I quickly hopped back into the car and babied it back home. I threw it up on jack stands and pulled the wheels and took them down the next day to get them replaced. I went out yesterday and put them back on. While I had it up on jack stands on, I decided to check the plugs because it was running a little funny. I knew I had a helicoil on the #4 cylinder and I read a while ago that you're supposed to run colder plugs if you have a helicoil on an aluminum head because they can't sink the heat as fast as aluminum does. I had to order an 8 range (NGK) plug because nobody carried it in town. It came in last week sometime, but I hadn't been to worried about replacing it because I've had these 7 range plugs in there since I rebuilt it and it's been fine. I should have put them in sooner;
Image

I'm going to do a compression test today and pull the CHRA out of the turbo to see if anything has been damaged. I'm actually pretty hopeful because of how well the engine was running and the complete lack of oil burning or anything. This is the same cylinder that that had issues on the last build. I'm wondering if the helicoil on this cylinder caused the issues I had last time too.

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Re: A Bad Day In CA18DET Land

Postby Buddyworm » Tue Mar 14, 2017 2:45 pm

I doubt your problem is plugs Float, 7's should be fine at your power level on the street. Your timing is overadvanced plain and simple. You usually see that kind of failure on an engine that's seen long stretches of WOT with too hot plugs or insufficient cooling. Top speed trials type WOT action.

Like I said before, too much timing just puts more heat into the metal engine parts. Your ground strap started glowing and it started lighting off the mixture before your ECU fired the coil. Aka: preignition. It probably progressed earlier and earlier into the combustion cycle and eventually you experienced insanely high localized pressures around the plug, shattering the porcelain and blowing off the weakened ground strap.

A full inspection for that type of failure should be an engine teardown to inspect bearings, wrist pins and ringlands on #4. They've been abused for sure.



You need to take a bunch of timing out of your map or you're just going to do it again. The CA18 straight up doesn't require as much advance as you're giving it.

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Re: A Bad Day In CA18DET Land

Postby float_6969 » Tue Mar 14, 2017 4:59 pm

I had just done a pretty long WOT stretch when this happened. Like 4k-8k in 2nd, 3rd, and 4th and was at about 6k in 5th. I've never had any hints of detonation or knock. The total timing under load is 27deg. That's not an arbitrary number, but was set on the dyno with a detonation microphone to ensure there was no knock. This is only 12-13psi of boost and about 320whp. EGT's never exceeded 1300F. I'm on E85 with an actual ethanol content of 85%. The issue is isolated to this cylinder. I had plug issues on the same cylinder with the last rebuild. The porcelain cracked and a piece came off and scratched the cylinder wall. The only thing that would effect this that was the same from the last build is this cylinder head. the entire intake manifold is different, the turbo is different, the cams are different, fuel injectors are different, pistons are different, and compression ratio is different. I didn't know that there was a helicoil in it the last time. I didn't even know about it until recently when I went to check the plugs after dyno'ing it and that cylinders spark plug felt funny when it came out, like it was steel-on-steel threads. So I stuck a magnet down in there and it stuck to the threads. Then I got a flashlight and realized it had a helicoil in it. I have read in the past and heard from engine builders that a helicoil in an aluminum head doesn't allow the plug to dump heat as easily as the original aluminum thread because the steel doesn't conduct heat away from the plug as well as the aluminum does. In high performance applications, this can require the use of a colder plug on that cylinder to prevent this exact situation. If you don't do that, it can cause the exact situation that you're describing, but it wouldn't be due to ignition timing, but instead, the plug it self not being able to conduct heat into the head like it's supposed to.

I'm pretty confident the plug overheated from the helicoil, but I'm never one to say I know it all. I'm going to do a compression test and go from there. If the compression is low I'll start inspecting the engine more closely.

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float_6969
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Car: CA18DET swapped 1995 Nissan 240sx (toy)
2003.5 Mazda Mazdaspeed Protege (lightly modded DD)
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Re: A Bad Day In CA18DET Land

Postby float_6969 » Wed Mar 15, 2017 7:29 pm

Well I messed with the engine a little after dinner tonight. I turned the crank so the #4 piston was at BDC and then looked down the plug hole with a flashlight. I could see the piston pretty well and I didn't see any damage. I could also see some of the cylinder wall and what I could see looked fine. I then tried to do a compression test. It's only like 40°F here right now. I tried to do the compression test cold, but it didn't really work. My battery charger couldn't keep up and the cranking RPM wasn't keeping up. The oil pump also primed from the cranking so much and that REALLY dropped the RPMS down, so I didn't trust the results. I was running out of daylight, so I just said screw it and threw some plugs in it to see what would happened. The engine fired right up and sounded fine. I let it run for a few minutes and everything sounded fine. It's supposed to be warmer tomorrow, so since I know it runs, I'm going to go ahead and warm it up to NOT and then do the compression test. I'll probably hook up my work truck to it with jumper cable to be double sure the engine RPM's stay up there. I'll update again when I know more.


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