Can i fully advance the timing on my stock JS550

[Js550FTW]

Sorry for making all of the new threads. just so many questions need answers. but i have a stock js550 with 110 psi comp. can i safley advance the timing all the way for more power, or will i just make the thing detonate. i heard it can make the thing like a rocket and some people say the thing will blow up. i want the real answer cuz if it makes it a bit peppier, then im gonna do that. Thanks guys!

 

[SmittySX]

Might want to take care of that compression before modding...

 

[Yami-Rider]

Well, you could try it and see what happens.
Stock compression is 130, so your a little low.

 

[Js550FTW]

well thanks guys! i have a top end kit with a copper head gasket for compression so yeah. oh, andi got the fancy dual ring pistons as well. so lets just assume the compression is goingto be around 135. can i run that and advance the timing. isit just the myth that it increases the whole powerband. i wantto try it but i am afraid of detonation. anyboy have some personal experience with this. ordoes anyone have smething to say bout this?

 

[SmittySX]

well thanks guys! i have a top end kit with a copper head gasket for compression so yeah. oh, andi got the fancy dual ring pistons as well. so lets just assume the compression is goingto be around 135. can i run that and advance the timing. isit just the myth that it increases the whole powerband. i wantto try it but i am afraid of detonation. anyboy have some personal experience with this. ordoes anyone have smething to say bout this?

I dont know what you mean by "all the way"... Advance it about 3 degrees to be safe.

 

[Yami-Rider]

I'm with smitty, don't advance it much. 550 have no bottom end and have to be held at wide open throttle everywhere, if you advance it too much it will most likely seize up at full throttle.

To each there own, but I don't think it's worth sinking a bunch of money into a 550, just ride it, enjoy it, then upgrade to something better.

 

[Js550FTW]

what i mean is turning it all the way counterclockwise. but thanks guys! whats the best bottom end mods while keeping the speed i want

 

[Quinc]

There is a good 440/550 thread on here somewhere and think it says you can do something like 17-18 degrees advance. But dont take my word for it, find the thread.

 

[oldschool440]

I ran my 550 for years with the timing advanced all the way and this was with a ported cylinder,coffman pipe,milled head and sbn 44 with no problems! Just run 93 octane in it! I could hold that thing pinned for awhile. I have a nice 550pp head that was milled by groupk I can sell ya,it ran 165psi on my ski, it will prob be around 170ish for you since my cylinders were ported and that brought down the compression a little.

I would start with timing advance and then the head and get a 15.5 prop!

 

[Bradford135]

I have ran fully advanced on all my 550s for a long time I would personally recommend it but it's up to you had detonation in one of 5 but it was more from poor upkeep and lack of preventative maintenance it was my beater ski I let everyone ride but my new engine is fully advanced as well