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CriScO
10-10-2008, 08:43 AM
I'm gonna sound like an ultra noob right now, but oh well... :hehe: I've never messed with timing before.

I've gone over the BGB procedures and I'm confident I know how, it's just a matter of getting the numbers I want. So, the 3S-FE timing is supposed to be:

Base: 10 degrees @ 650rpm Advance: 13-22 @ idle.

So if I wanted to advance it 5 degrees, then I would want to set the base to 15 @ 650rpm, correct? With that, the advance should then be 18-27 @ idle, right?

Sorry for the basic question guys, my head ain't been working right lately and I want to make sure. :)

Shadowlife25
10-10-2008, 10:54 AM
Sounds correct sir. I'm getting a migraine right now... fail.

So why the timing bump? Just curious. :)

CriScO
10-10-2008, 11:36 AM
*shrug* Thought I'd see what it would do. :) Just wish I would've got around to it before the track closed...

greenmachine87
10-13-2008, 03:42 AM
whats your time with out the timing advance

CriScO
10-13-2008, 04:19 AM
19's yo! :hehe:

Best run was like an 18.8.

What? You guys try hooking up thirteens! :)

DaneDog311
10-31-2008, 07:54 PM
Timing advance has it's advantages at a higher RPM but in order to prevent spark knock you need to keep to a slower burning fuel (AKA 93+ octane) I have my 93 at around 17 BTDC on 93 pump and have no hesitation or knocking so... I heard guys doing more but I personally wouldn't without having higher lift and shorter duration cams

ciento44
10-31-2008, 08:10 PM
Timing advance has it's advantages at a higher RPM but in order to prevent spark knock you need to keep to a slower burning fuel (AKA 93+ octane) I have my 93 at around 17 BTDC on 93 pump and have no hesitation or knocking so... I heard guys doing more but I personally wouldn't without having higher lift and shorter duration cams

Actually, advancing your timing tends to give you more low end grunt.

We tested this on a 92 Integra GSR. We advanced the hell out of the timing using Crome, and it picked up a TON of low end.

We then went back and took it way back, the car was STUPID SLOW out of Vtec, and then around 6000 rpms, it felt like you got hit from behind by a freaking cement truck.

I have my 92 at 17 BTDC now that i've taken the nitrous back off, and i run 92 with no issues. I never rev this thing past 4500 anyways, so it does great for driving around town like i do.

That being said... i DID run the dragon at close to 30 BTDC, and i didn't ping or hesitate there, either.

Kastigir
10-31-2008, 08:36 PM
Is the power boost worth the extra cost in fuel?

ciento44
10-31-2008, 08:48 PM
Is the power boost worth the extra cost in fuel?

If you're worried about paying an extra $1.50 to fill up your car.... probably not. :lolhittin

Personally, i was able to run 15 degrees on 87 with no issues. Your car may vary.

It's not a HUGE power boost by any means... just makes it a little more enjoyable to lug around. I can pull up hills in 4th gear at 20mph if i have to.

DaneDog311
10-31-2008, 09:58 PM
Actually, advancing your timing tends to give you more low end grunt.

We tested this on a 92 Integra GSR. We advanced the hell out of the timing using Crome, and it picked up a TON of low end.

We then went back and took it way back, the car was STUPID SLOW out of Vtec, and then around 6000 rpms, it felt like you got hit from behind by a freaking cement truck.


Your theory may be true but we are talking Variable Timed against straight NA... advancing your timing on a car with variable valve timing is like pissing in the wind kind of.... the variable valve timing is to compensate for the a/f ratio at higher RPMS... 13:1 is the optimal burn ratio and I am under the impression VTEC or VVTI does this on it's own... that's the purpose... on an NA car the valve timing does not change... so advancing the timing on a VTEC or VVTI would through your top end way out of range because the car is trying to compensate at higher rpm hence the VTEC or VVTI ... someone please jump in... I may be wrong here...

Kastigir
10-31-2008, 11:16 PM
If you're worried about paying an extra $1.50 to fill up your car.... probably not. :lolhittin

Personally, i was able to run 15 degrees on 87 with no issues. Your car may vary.

It's not a HUGE power boost by any means... just makes it a little more enjoyable to lug around. I can pull up hills in 4th gear at 20mph if i have to.
At current fuel prices I'm not, but when/if we hit the 5+/gal range, then I might be. The Talon is already going to require 93, so perhaps the Celica should just stay where it is.

ciento44
11-01-2008, 03:24 AM
Your theory may be true but we are talking Variable Timed against straight NA... advancing your timing on a car with variable valve timing is like pissing in the wind kind of.... the variable valve timing is to compensate for the a/f ratio at higher RPMS... 13:1 is the optimal burn ratio and I am under the impression VTEC or VVTI does this on it's own... that's the purpose... on an NA car the valve timing does not change... so advancing the timing on a VTEC or VVTI would through your top end way out of range because the car is trying to compensate at higher rpm hence the VTEC or VVTI ... someone please jump in... I may be wrong here...

Vtec isn't valve timing, it's a secondary set of lobes on the cam. It doesn't affect timing in itself.

A timing advance increases low end great, a retard increases top end. We've had someone experience that on their 3s just this week.

DaneDog311
11-01-2008, 12:09 PM
cams decide when the valves open and close wouldn't that be timing them?

Honda's definition of VTEC is - VTEC Variable Valve Timing and Lift Electronic Control System

although i did check into the theory you do get more low end from timing advance...

DaneDog311
11-01-2008, 12:14 PM
Never mind... I'm crossing Ignition timing with valve timing... not thinking correctly here... my bad... thanks for the info

glenn
11-02-2008, 07:41 AM
okay wow i'm such a noob what is BTDC and also how do you advance timing? i've been told you can do it by loosing the dizzy and turning it a certain way? plus i've seen the cam gears that have the little bolts and i bunch of little lines that gauge i would say the timing but can someone direct me to this stuff so i can read and learn

CriScO
11-02-2008, 08:13 AM
BTDC = Before Top Dead Center. As in how many degrees of rotation the crank is turned before the piston reaches the top of it's travel. Zero degrees is top dead center of the number one piston. So what this means is that as the crankshaft turns, the spark will fire in the number one cylinder just before that piston reaches the end of it's travel. So at the stock timing the spark occurs ten degrees before the crank hits the zero mark.

Click the BGB link at the top of the page and go to the "Technical Articles" section. The file is called either "4cyltuneup.pdf" or "tuneup.pdf", I forget which.

CriScO
11-02-2008, 08:20 AM
Sorry, you need to go to the home page to access the BGB section. Duh! :)

BTW, I love when one of my "brain fart" threads turns into an actual discussion. :hehe:

glenn
11-02-2008, 09:41 AM
okay well is it just me or is the whole bgb thingy jacked up to hell and also i dont know where to look for the tuneup4cyl either

CriScO
11-02-2008, 04:28 PM
The BGB's are being worked on.

Yeah, I guess I just assumed the file would be similar in the fifth gen book, guess not... Here's the fourth gen one, procedures are the same:

http://www.celicatech.com/imagearchive/bgbonline/89tech/tuneup%204%20cyl.pdf

DaneDog311
11-02-2008, 11:36 PM
I messaged someone about the 5th gen BGB's I have the second manual almost done... but i can't be positive it will work without it being uploaded... I work alot and screw around in my spare time... when i have it completely done... I'll harass Luni until he puts it up... but until then or until someone beats me to it... you gotta deal with it... it's still TONS of great celica info... :)

CriScO
11-03-2008, 05:28 AM
If you've got most of it I'd PM Luni now, the files have to be prepped a certain way. Actually, PM Mario, Shadowlife25. He's volunteered to to do a lot of the work, so he should be able to work with you on it.

glenn
11-03-2008, 08:36 AM
so let me get this strat when you turn up the rpm's at idle by the distribtor you advance the timing ? correct me if i'm wrong plus also the idle screw it self on my car doesnt change shit ever... i've messed with it a million times and it never raised or lowered my idle rpm's....

CriScO
11-03-2008, 08:55 AM
No. The idle speed and timing, though linked, are two seperate entities. The timing needs to be set at the correct idle speed, but it shouldn't change it.

DaneDog311
11-04-2008, 03:30 AM
thanks i'll get ahold of shadowlife25... sorry to get OT

CriScO
11-04-2008, 05:28 AM
No problem, it was brought up. :)

What do I care anyway, this isn't my section. :hehe: j/j

glenn
11-04-2008, 07:38 AM
okay well why when i loosing my dizzy and turn it a certain way it changes my idle speed is that a bad thing ?

CriScO
11-04-2008, 07:40 AM
That's why you fix the idle speed by jumping the check connector.

MrWOT
11-04-2008, 05:18 PM
You fix the computer curve by jumping those pins, with the dizzy centered, the timing should then be at 10btdc. If you move the dizzy after that and the idle raises, you advanced it.

The more you advance your timing the closer to TDC you move peak cyl pressure, the downside is that more negative work is being performed as the pistons is fighting an increasing pressure before TDC for longer, and that also increases the heat load in the piston, and the higher pressure can lead to detonation OR preignition.

On another note, vvt is primarily used to vary overlap, in newer cars, you wont notice an EGR valve, because they contol EGR through overlap and intentional reversion ;)

CriScO
11-04-2008, 08:23 PM
Ah, my mistake, thank you WOT.

glenn
11-04-2008, 11:27 PM
okay lol so how do i know if my dizzy is centered lol i know noob questions but i'm a total noob with this stuff lol

MrWOT
11-04-2008, 11:35 PM
You can't tell where it is once it's been moved, only way to know where it is, is with a timing light with the jumper in place.

85gtsblackman
11-06-2008, 07:44 AM
you have taken one of the most simple mods and made it complicated, go out, put whatever grade of gas u will use all the time in your tank, get a 12mm wrench and drive and adjust the dizzy so that u have no pinging under load with the a/c on

glenn
11-06-2008, 08:27 PM
well i'm sorry i just really have no clue what i'm doing and trying to learn it

ciento44
11-06-2008, 09:33 PM
^ It's ok buddy, he wasn't ripping on you or anything. Just giving you an easy relatively safe way to do it. :)

glenn
11-08-2008, 11:46 PM
gotcha lol well what if i dont have AC? lol

ciento44
11-08-2008, 11:58 PM
gotcha lol well what if i dont have AC? lol

Then go for a test drive, put the engine over load, and if you hear any weirdness, back it off some. The motor will survive a ping or two if need be. :)

glenn
11-10-2008, 12:32 AM
okay lol well i'll hook up the AC when i get the motor back in the car