Cool, are they the same shape, just no letters? I would prefer the same shape...
Printable View
Cool, are they the same shape, just no letters? I would prefer the same shape...
MMmmmm lumpy ;)
http://www.turbo-mopar.com/forums/ph...ignmapSRT4.jpg
if you havent seen this... SRT-4 base timing map that is supplied with AEM systems.
btw, that is total timing, no base advance
Brian
What CR do you have JT?
Wow JT. That looks amazing! I'm always blown away by your work.
I don't know if it's been asked yet, but what are you using for electronics??
Is that pump gas timing?
yes thats the factory pump gas timing for the SRT4, as stated earlier in this thread thats why people have probs when switching to a larger turbo, lots of timing, breaks the oil pump gears from detonation and cracks the ringlands.
I think the stock ramp style pistons like more timing then dished pistons from what I understand, so when they switch to a higher CR piston and dished quench design they have major probs if not done properly. Thats why on SRTforums I allways suggest running the lowest CR possible. IMO there is not a good off the shelf piston for the SRT4 motor(using a stockish computer) because they are either stock ramp style( which I dont care for) or dished raising the CR, the 8.5CR JE's are the lowest common dished piston and dont have large enough valve reliefs for larger than Crane 14 cams.
Someone needs to get there act together and make a damn piston w/ like 8.3CR/dished and large enough valve pockets.
Then again I'm running ~9:1CR, but have the timing very low in comparrison(almost 1/2 the stock SRT4, hint JT:thumb: )
Yeah, there's no way I'm going close to those stock numbers ;)
What are the numbers on the left side of the scale?
Kpa... i have another image that i converted to psi, lemme see if i can find it.
here it is. i think those are the correct values.
http://www.turbo-mopar.com/forums/ph...apSRT4-psi.jpg
Brian
I am still confused by you guys that are at 10-15* timing at WOT. Weak stuff man.
On the SRT4 stuff, a bunch of them run AFC's or other hack devices that make the pcm think they're at lower boost levels so it doesn't dump so much Effing fuel, because they run them very, very rich. Except then they run rediculous timing.... way rediculous.
aaron, so are you saying that the map posted is way too aggressive?
do you have the resources/experience to suggest some better timing values and edit them into the pic?
I am helping a friend tune a 2.4L swap in a 97 eclipse sometime within the next year and id like to start with a somewhat safe base map as he and i still need to work on a good knock detection setup. he is running megasquirt II. plus I think that we all could benefit from this.
thanks
Brian
Its no 8valve
My vac and 100Kpa values are basically the same as that map(basically 2 deg less except for idle)
This was posted by Kevin Davis on TD awhile ago
"Yes he is talking total timing,I talked with bill hahn and some other people darrel cox etc. about total timing with the pent roof stlye head when I was building my 2.4 dohc.This is what bill hahn told me,@ 8.6:1 comp. with the sc6152 turbo 15 psi is max with pump gas @ 15 to 17 total if you go to 21 psi 110 octane, 26 psi 114 anything else c16. I found that with the automatic its more like 13 or 14 I was getting slight knock at 15 degrees.Like brian said the pent roof style head is so efficient and such a fast burn head with its central plug location it just doesnt need the advance.Darrel cox said @30 psi with c16 keep it between 9-12 total if you need more power raise boost dont increase timing he was bending aluminum rods.Usually the first thing to break on the 2.4 with serious detonation is the oil pump then it just escalates from there.Sorry not trying to hijack thread but thought this would be some good info for the dohc guys"
Also heres a good formula for dynamic compression ratio
the formula is: (actual boost/14.7)+1 xCR).
so right now I'm running(15/14.7)+1x9.0), which =~18.2:1cr