VTC_CiViC

I know some of you have followed my uncontrolled boost dilema on my wife's GSR, well that of course only led to the discovery of even more problems, namley the fact that no matter what I did, I couldn't sync the base timing with the ignition map. I decided to go ahead and take a few other preventative steps since there were alot of question marks with this car since I bought it. Picked up a new Walbro 255 pump and a set of RC 650's. Previous owner assured me there was a Walbor already in there but I figure it's cheap insurance since there like $80 new. Go ahead and pull out the old pump and what do you suppose I find? Yep, original 17 year old Denso/Honda pump.. nice, guess that explains those random lean moments where no matter what I do the damn thing runs out of fuel in boost.

Go ahead and swap the injectors, ran the part number on the old ones and this time it was actually as advertised, 550cc Racetronix/Siemens Dekka. I learned a lesson with my old GSR to always check injector reistance despite what they were sold as. Sure enough all 4 RC's check out at 12ohms. Just for giggles, let's check the original ones... 2.5ohms, 2.4ohms, 2.5ohms, 2.2ohms. Wow, low impedence injectors with NO resistor box! How the car runs as well as it does is beyong me, but this thing is a time bomb waiting to go off.

Finally get the fuel system set, plug up the new AEM v2 and decide that with all the timing headaces, I'm gonna try on last thing and see if I can't figure this out. Everything up to this point is making me belive the head has been milled (cams appear slightly advanced with the crank at TDC, excess belt slack etc..) so I toss a set of adj. cam gears and set the timing to what would be TDC for the cam... EUREKA! Timing matches perfectly on the map and the crank, guess that answers the questions about the head being worked.

Now I can finally iron out the map and get some results out of this thing. 6 months later and we still have yet to enjoy the car, take it as a lesson learned, if you don't know the seller, you might wanna think twice before picking up somebody esle's project!

Universal Magnetic

Could you imagine owning a performance shop and having to deal with these types of problems? LMAO!

If someone gave me a nickel for everytime I've heard someone say "My car is ready to be tuned.", i would already have my M400

thumbsup to you for figuring stuff out!

SiRCiviC94

I dont think people research go at it and then end up hacking **** up pretty bad. good story you seem good with mechanics....its a tricky game when everything is aftermarket

BigMike0147

How off was the timing?? I've had my current head milled and I haven't seen any timing issues. They must have taken off A LOT!

racebum

the cams advancing when you mill the head, or, head and block like a typical rebuild push the timing +1deg for every .015? .020, someone should remember the exact number.

VTC_CiViC

it was like 5-6* at the cam + /-

kbouchard1092

Are you saying ignition timing was off 5-6 degrees? or you saying you had to move the cam gear 6 degrees to get it at TDC? Generally .012" milled is 1 degree retarted since milling advances cam timing...so you need to retard to get back to proper tdc. but this is a rule of thumb. IF you had to change 6 degrees cam timing that would be a crazy amount of milling done(and would explain the slack in the belt)...well past the service limit im sure

VTC_CiViC

At maximum physical advance (distributor pinned to the firewall) the car would see approx. 10* retarded from the ignition map. Took about 5* at the cam to make the map sync with the crank.

kbouchard1092

Its a DOHC right?...how many degrees per cam was taken off? you just took 5 degrees from the exhasut cam, or did you adjust both?

is this at idle? (when you were getting 10degrees with dist pinned to firewall?)

Tony the Tiger

The timing can go either way.. It depends on where the slack is on the timing belt. I am inside the same building as my engine builder, so I get to see a lot of similar situations. You can sometimes still line up the marks a lot closer even if the head was milled a lot. It's one of those things that are slightly different with every engine.

On one of my old setups (GSR head, milled a little over 0.090" over the course of its 13-year lifespan), I had to advance the cam timing by +7 deg both IN/EX to get the motor properly degreed. Just for reference.

VTC_CiViC

Pretty much where I am now, how did you deal with the excess belt slack? Fear of this thing jumping on me is keeping me awake..

Whiterice-gsr

how did it not blow the ecu without a resistor box is what i wanna know.

wantboost

iTrader: (2)

This is why we closed our shop... tired of having cluster****ed projects roll into the shop that seem to be never ending headaches...

kbouchard1092

Wow pretty crazy....never had a head milled that much. What is the service limit? at what point is the head been milled too much and cannot be used...Wouldnt a head with .090 taken off have a much greater risk of P2V contact? Seems like youd be limited on cam choice ie. Pro 1's...i could be wrong just seems really excessive

fastgtr

Thats alot to take off a head and still be usable.