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Old 06-01-2010, 12:39 PM   #1
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Proper way to set SR20DET Ignition Timing?

I really need some assistance on setting the ignition timing to 15* BTDC on a stock S13 SR20DET.

I know it needs to be set to 15* BTDC and I know this is the second to last mark on the crank pulley. I have marked this with white out and have access to a timing light. My problem is this, what is the best way to set the ignition timing? When I set the timing by attaching the pickup for the light to the 1st coil pack, and the MAF is plugged in, car warmed up, the signal is somewhat jumpy, but when i adjust it to 15* on the crank, the CAS is maxed out almost all the way advanced (no gap between the CAS adjustmetn and where it bolts to it, its maxed all the way out almost).


If I unplug my MAF and set it to 15* it has a very smooth signal and it appears to be in the right area (the CAS is adjusted slightly advanced and there is a small gap between where it bolts to the head). I have read to unplug the TPS, rev it a few times to lock it in timing mode, then time it off the black wire in the back of the motor on the coil pack harness?

I'm really confused. Also, I know how to remove the valve cover and put the CAS back in that way (like the FR sport guide How To Set Crank Angle Sensor (CAS) Timing on the SR20DET Engine)

The main reason i ask is because currently my car has a Gt2871RS .64 set to about 9-10 psi. The downlow power just feels slow compared to my friends stock T25 car. He has a stock redtop and has never adjusted the timing. His car feels like it pulls harder down low and even when he is WOT past 5500 rpm, his car just feels awesome and we have very similar setups. I'm not sure if the lack of downlow power on the 2871 is from my timing or just because its that much larger than a T25?

My specs are
Stock S13 SR20DET redtop
GT2871rs .64 stock manifold
Brand new wiring harness (helped with idle and overall smoothness of car)
FMIC
3" turbo back
pretty standard, stock MAF, injectors and FPR

This is the only video I have of the car running/driving around.

Quick pull on Vimeo
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Old 06-01-2010, 02:22 PM   #2
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pop the valve cover and put you motor at TDC. Make sure that line on the CAS is aligned with that little dot like FRSport shows. When you set ignition timing you have to unplug your TPS not your MAF.
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Old 06-01-2010, 02:39 PM   #3
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It is, I have set it to the specs per FRSport guide. From here, I'm asking how do I adjust the Ignition timing - so you do unplug the TPS? I'm just stating I seem to get a better reading with the MAF unplugged, but I know it should be plugged in.
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Old 06-01-2010, 04:29 PM   #4
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Quote:
Originally Posted by TrustS13 View Post
It is, I have set it to the specs per FRSport guide. From here, I'm asking how do I adjust the Ignition timing - so you do unplug the TPS? I'm just stating I seem to get a better reading with the MAF unplugged, but I know it should be plugged in.
leave the maf plugged in, the only thing that needs to be unplugged to set the timing is the tps. leave it unplugged and rotate the cas till you hit 15*, bolt the cas down and plug the tps back in and your done.
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Old 06-01-2010, 04:54 PM   #5
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It revs up to like 2k RPM when I unplug my TPS. Do you rev it up a few times to lock it into timing mode, or what? It seems like at 2k RPM It isn't going to get a proper signal on the light, but I will try it out.
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Old 06-04-2010, 12:49 PM   #6
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TIMING
Get a spark plug wire, plug it in the #1 coilpack with Spark Plug #1 in order to be able to connect the timing gun...

Disconnect TPS (NOT THE MAF!) hold it at 3k for a little bit...

Start To adjust it...its actually 13* degrees not 15*

On the power Issue:
Your car with GT2871rs vs. a Stock T25 will feel way slower on bottom end... T25 has a different efficiency usually falls on its face around 6k where the GT28 will continue to pull to rev limiter... Its just how it is... If you dont have the supporting mods like more fuel and more boost with the GT28 you wasted your money.

Good luck
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Old 06-04-2010, 05:53 PM   #7
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even though this has been gone over like thousands of times....

99% of the cars I tune or check out or diagnose always have the timing improperly set.

It's like a black art I guess.

Another thing people forget to do is synch their timing with their maps.

You must synch your standalone to your cas.
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Old 06-04-2010, 05:58 PM   #8
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if your chasing timing and your cas is clocked completely one way or another its off a tooth..
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Dude if I made 500WHP on a 54C SR20DET back in 1999-2000 with old school technology .. This VET will T-BAG your RB engines
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Old 06-04-2010, 06:00 PM   #9
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ehhh....in my experience the actual CAS is just f'ed

Usually...not always...but most of the time, if you are a tooth off the car won't run

And if you need to move a link just to get the CAS to allow you to touch the edge of right adjustment the CAS is what's f-ed because you probably lined it up right when you punched it...
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Old 06-04-2010, 06:04 PM   #10
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i meant on the cam gears.i had that problem once ,and when i was trying to time it i was hafin to rotate the cas all the way to even come close to 15*..
ps,we need to talk,im finally almost done with my block and need a basemap,this one is gona suck lol...
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Old 06-04-2010, 07:41 PM   #11
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Quote:
Originally Posted by steve shadows View Post

Another thing people forget to do is synch their timing with their maps.

You must synch your standalone to your cas.
what do you mean by this? how do you sync the cas to your standalone?
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Old 06-06-2010, 06:06 PM   #12
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if you're good at something never do it for free hahaha

but seriously very very few techs do this or do it properly. but this is the most important step when you're setting up a standalone on any car.
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Old 06-06-2010, 06:43 PM   #13
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Quote:
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what do you mean by this? how do you sync the cas to your standalone?
Quote:
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if you're good at something never do it for free hahaha

but seriously very very few techs do this or do it properly. but this is the most important step when you're setting up a standalone on any car.

yeah, I too want to know what this means?


I mean I know PFC has a function where you can adjust all timing values at once (through the IGN setting in the commander)....but if your CAS is in properly, everything should be good to go, right?
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Old 03-04-2011, 11:25 PM   #14
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Quote:
Originally Posted by inopsey View Post
what do you mean by this? how do you sync the cas to your standalone?
Quote:
Originally Posted by jspaeth View Post
yeah, I too want to know what this means?


I mean I know PFC has a function where you can adjust all timing values at once (through the IGN setting in the commander)....but if your CAS is in properly, everything should be good to go, right?

Do both of you lack common sense? I'm not sure about the PowerFC, but any standalone, you have to synchronize the timing.

You finish installing a haltech on your sr20, load an ignition map. That map is useless until it has a reference with the CAS.

You need to tell any standalone, "THIS IS 10 Degrees" and then SET the CAS to 10 degrees.
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Old 05-10-2011, 02:28 PM   #15
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Quote:
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if you're good at something never do it for free hahaha

but seriously very very few techs do this or do it properly. but this is the most important step when you're setting up a standalone on any car.

Wow, what a dick comment.

All he is saying is that your tune was designed around a certain base-engine timing mark. From the factory it's 13 degrees... With a full standalone this can be changed so you need to make sure the engine timing matches the ECU timing. There is no "set" way to do it, it depends on what EMS you are using.
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Old 06-21-2011, 09:11 PM   #16
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Set the map to 15 degrees

Set the CAS to 15 degrees

if you want to start at 10 - 2 - 100 degrees go for it! There's no set way right?

The suggested manual method to override any specific EMS "Timing Lock" controls or function is to set the map manually to 15 degrees in the cells in the map where the Engine is scaling through or hunting through at idle or at the rpms ranges where you are checking the timing with the timing gun...

If you don't do this then you can still tune the car on the dyno but the timing map will probably be way off and hard to compare to other tuned cars etc, the timing advance may be 10 - 20 degrees too advanced or too retarded in the map during runs because it's just making power wherever the settings happen to be in the EMS map file and not scaled off base suggested BDTC with the CAS...
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Old 06-22-2011, 12:32 AM   #17
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Well on a PFC, it's fairly ease to do... the IGN timing is show on the controller... all you need to do is put a Timing Lamp on a spark plug wire, connected between the #1 coil pack and the spark plug...

You take a look at the value of the IGN timing on the controller... and then adjust the CAS 'till the timing lamp shows the same value...

That's it!

See ya!

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Old 02-03-2016, 07:52 PM   #18
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So I'm trying to take off the head on my sr20det (due to head gasket) and literally can't find the marks on my timing chain theres only 1 gold one and thats it, how can I set the motor to TDC?
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Old 02-03-2016, 08:30 PM   #19
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remove the spark plugs, get a really long screwdriver, or anything else that is long enough and put it in the spark plug hole so that its making contact with the top of the piston...

Then spin the crank over by hand. Youll notice that the screw driver, or what ever you have in the sparkplug hole, will start moving up or down.

Spin it until it the screwdriver goes up as much as it can, youknow the piston is at tdc when the screw driver starts to go back down.

Just verify youre at tdc by looking at the marks on the crank pulley, as well as making sure the cam lobes facing opposite directions. exhaust cam lobes should be "pointing" towards the drivers side fender and the intake towards the passenger side.
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Old 02-03-2016, 08:35 PM   #20
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cylinder 1 cam lobes are what I was referring to when saying they will be facing the driver/passenger side fenders.
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Old 02-03-2016, 08:40 PM   #21
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well like i can see the 2nd mark on the crank pulley number one cylinder is all the up but my chain has no marks on it
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Old 02-03-2016, 09:02 PM   #22
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top dead center is top dead center. Doesn't matter if your chain has marks. If I remember correctly, some don't. Now would be a good time to mark your chain though.

Just make sure everything else is correct. If number cylinder 1 cam lobes are facing out, on both intake and exhaust, and the crank pulley is lined up with the second mark from the left (0 degrees) you should be fine.
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Old 02-03-2016, 09:03 PM   #23
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And do your cam sprockets not have the dots on them?
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Old 02-03-2016, 10:41 PM   #24
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No my cam sprockets do have dots on them! and lobes are facing out so I guess I'm just being overly cautious, my first time pulling the head off
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Old 02-04-2016, 05:12 AM   #25
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Quote:
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top dead center is top dead center. Doesn't matter if your chain has marks. If I remember correctly, some don't. Now would be a good time to mark your chain though.

Just make sure everything else is correct. If number cylinder 1 cam lobes are facing out, on both intake and exhaust, and the crank pulley is lined up with the second mark from the left (0 degrees) you should be fine.
This is correct, but I just wanted to mention that you can put a long screw driver down #1 Cyl and as you rotate the crank, watch it go up and at TDC (Compression) cam lobes facing out (< >) and 2nd mark from left, your key ways on your cams should be 10' oclock and 12' oclock. I had a f'd up problem where the previous owner installed the cams a link off each and my dots lined up with the dark colored links, 9 links in between, but my cam lobes were slightly pointed up on intake and slightly down on exhaust...the dots were more like 11'oclock and 1 oclock.

The Exhaust cam key way is the easiest because its 12' oclock and verify that 2nd mark from left is truly TDC and when you stab the CAS it looks exactly like the frsport guide.
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Old 02-04-2016, 01:28 PM   #26
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What should I mark my chain with? so I can put the chain back on where it was
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Old 02-04-2016, 01:44 PM   #27
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The marks on my cam sprockets are at 11 o clock and 1 o clock and the crank pulley is at the 2nd mark from the left
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Old 02-04-2016, 01:50 PM   #28
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Count the number of links from the mark on your exhaust cam sprocket to the mark on the intake sprocket. Should be 11 links from mark to mark, or 9 links inbetween
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Old 02-04-2016, 04:21 PM   #29
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The marks on my cam sprockets are at 11 o clock and 1 o clock and the crank pulley is at the 2nd mark from the left
Where is the key way on your exhaust cam? It should be 12'oclock at TDC on the #1 Cylinder compression stroke...my mating marks lined up just like yours at 11 and 1 at TDC and i ended up being a link off

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Old 02-04-2016, 05:39 PM   #30
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Mine are exactly how yours are 11 and 1 at tdc
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