Adj FPR with bigger injectors

[lexcrob]

Can you use an adjustable FPR to allow an engine to run with bigger injectors?

I would imagine it would only work with "slightly bigger injectors ...

It would allow factory psi to be turned down then when an FMU came into play you get a few more psi before you run into really risking inj. failier.

^just thought it might work i agree probly not most effective but id say it would work! Also NA guys could run a touch bigger injectors if they NEED it (higher compression/big cams etc.

It be a cheap alternative even tho youd have to do allot of fiddling same goes for safc and other alternatives. Some say mechanical adjustments are more reliable than "electical" Piggy backs only of course.

Anyone done it soing it etc?

[lexcrob]

Maybe you could run BIG ones and tune fuel psi down to really low like 20 then if you had 8:1 fmu youd be able to go to 8-10 psi compared to 5-6psi.

[biggie]

I'll just go ahead and say no.

[WDRacing]

Not a good idea. If you're going to use larger injectors, just save for a rom tune.

[lexcrob]

^ agreed id normally opt for that but i cant say there is an affordable option thats entry tunner friendly you have to be licensed or you have to use crapy shady freeware -please correct me if im wrong-lets hear success stories

Ok i guess a JW send out tune would probly be affordable and get you close enough to fine tune with safc<--

[lexcrob]

So it cannot be done tho.......

Is there an oem/swappalbe injector that is just a tiny bit bigger? rx7 maybe???

[biggie]

Any bigger without tune is bad.

You can find used JWT and Enthalpy tunes.

[WDRacing]

EFI Specialist's tune is only 350 and I hear good things.

[SiDwAyZ240]

There is enthalpy, JWT, etc. rom tunes used all over forums for sale around the $200/shipped price.

I think a FMU could be had for less than that if your only going a little bigger and looking for less than 10 psi.

[lexcrob]

^ YUP got fmu for 100$ shipped

Ok bad idea....ill probly just go SAFC with an msd unit to control timing

*how do you know that your timing is not to far advanced besides the obvious loss of power*
-more or less why would an engine blow if it never runs lean but ignition to advanced???
_how would you street tune timing as far as boosted>

[lexcrob]

I advanced my base timing on my old integra till if butt dyno'd or felt the strongest.... check it with light and it was bout 1.5 deg. advanced from stock setting.

I talked to a local shop owner and he said " i would put it back to stock even tho you prolby will make slightly more power you will run ALOT hotter" I noticed coolant temp even on my factory gauge were higher than before.....is that why to hot MELT DOWN!!!!

[WDRacing]

Knock is all about increased cylinder pressure. It doesn't matter how you go about increasing it, be it higher compression pistons, boost or increased timing, then end is the same, higher cylinder pressures. Higher pressure gives a bigger bang, more bang = more power.

With that said, if you increase the cylinder pressure by using a turbo you're going to want less timing to avoid detonation. Why? Because the cylinder pressures get so high under boost that having the spark occur too early will have the flame front pushing down on the piston as it's trying to come up.

It's easier to pop a motor by running to much timing then it is by running lean. I've had to much retard before and run in the 13's for my AFR under boost without knock. But I've also had to much timing while running very rich and had knock register under boost.

My rule of thumb is .5 degree's of retard for every 1 psi of boost once you go over 4 psi. This is retard done at the ecu or by a MSD though, not at the base. That way you don't lose mileage and power while driving off boost.

Help any?

[neverlift]

[lexcrob]

^ saved it to folder for reference

I never really thought about ignition timing affecting cyl. pressure. Good TIP!

this sound right? Ex: if say you increase compression from 8:1 to 13:1 you would retard the timing because the combustion process would begin earlier due to increased pressure-

If you retard to much you obviously lose power and to fig out the best advance would probly be on a dyno when it reaches peak power??? As soon as power dropped off as you advanced youd know your bout to or did KNOCK"

How would you street tune timing....G-tech ?



^sound right? thats what i got .....

[lexcrob]

So in other words for partial throttle your just kinda adding retard per "increase in pressure" but how much exactly is a educated guess????? Unless your on a dyno that you can tune for partial throttle.....<

[SiDwAyZ240]

WD- What's the best MSD product to do the said timing retard? There are tons of products out there and some are cheap and some are real expensive. Makes choosing the right one scary.

[WDRacing]

MSD BTM