Injector CC Rate

[SpeedySweetie]

Hey all.....

I'm new to the import tuning thing but not new to cars (have been circle track racing a Dodge Daytona for 2 years). My Dodge turd finally blew up in September and I bought a 89 Accord LXi to turn into my new racer. I am soooo lost! I'm hoping you all can help me out while I learn all about my new baby. My question is this: does anyone know what the stock injector cc rate is in the 2.0L motors? I'd like to bump up the fuel delivery rate, but don't want to have to install a fuel pressure regulator or bigger fuel rail (we're supposed to limit the value of our cars to $800). I already installed a resistor in the IAT sensor.

BTW, other mods to the car are a CAI, battery relocated to rear, entire interior coming out (& my Kirkey seat & race harness getting installed), A/C & cruise removed, headlights & headlight motors out, Falken Azenis 205/50/15's (need 4x100 4 lug 15" steelies to mount them on if anyone has some for sale!), drop zone coilovers (lowered 3.5"), ractive 9mm plug wires, quick-disconnect steering wheel, window net, lexan front windshield, battery master disconnect switch, weight & ballast added to gain better wedge, homemade strut bar, preloaded sway bar, full 6 point cage being installed, and hopefully will get an MSD and irridium plugs.

thx!

[Vinny]

its listed at 235

[AccordEpicenter]

nope thats our displacement... 240cc is the stock honda injectors for these cars... peak hold injectors

[SpeedySweetie]

nope thats our displacement... 240cc is the stock honda injectors for these cars... peak hold injectors

So maybe a 270cc injector would give me more punch w/o having to buy the rail & regulator....

You guys rock! Thanks a for the info...I'll be sure to thank you in Victory Lane! XXX's&OOO's

[night]

i see no reason u even remotely need bigger injectors

[AccordEpicenter]

umm.... try a b&m command flo FPR for honda civics... itll adjust your fuel pressure for like $50... I think 270cc injectors is a little on the large side for an N/A accord.. id just bump your fuel pressure with a cheap fpr. Take it to 40-42 psi fuel pressure and youll get all the fuel you need.

[Accordtheory]

increasing the fuel press/delivery on a stock or mildly modified engine is counterproductive..the ecm has a fuel correction factor under closed loop of up to 30%

[shepherd79]

there is no reason to run bigger injectors on NA motor. you will just run very very rich.
unless you have forced induction i would stay away from upgrading the fuel system.

[smufguy]

on a NA motor, you can run full ignition adv on the distrbutor and run 43psi of fuel pressure and not detonate. I have tried it and it works. I detonated at full ignition adv and 37psi.

[night]

spark advance is not ideal btw

[PhydeauX]

He/she/whatever is going to be racing the car circle track, the car is going to be at wot most of the time and running in closed loop so the fpr should have some effect. The a20 loves to be run on the richer side of things so there are probalby a few extra hp to be picked up with a fpr in this case.

[smufguy]

spark advance is not ideal btw

not entirely. spark adv with leaner AF ratio gives you more response but it also drops the exhaust gas temperature. But this also leads to overheating under continueous heating. Also spark advance is good to make more power cause it lengthens the total time of combustion which also reduces the CO and HC emissions, but increases the NOx emissions cause of the prolonged combustion time. As a matter of fact, if you knew anything about engine dynamics or have taken a class regarding internal combustion engine, you will know that ignition advance, is actually a complex activity that not only depends on the engine load but it also depends on how the engine is used.

This might be kinda out of place, but the rally cars retard their ignition timing 40deg on turns and causes the combustion to occur in the exhaust manifold to keep the turbo spooling. Weird, but this is to point out that the ignition settings depend on the usage.

[Sean]

not entirely. spark adv with leaner AF ratio gives you more response but it also drops the exhaust gas temperature. But this also leads to overheating under continueous heating. Also spark advance is good to make more power cause it lengthens the total time of combustion which also reduces the CO and HC emissions, but increases the NOx emissions cause of the prolonged combustion time. As a matter of fact, if you knew anything about engine dynamics or have taken a class regarding internal combustion engine, you will know that ignition advance, is actually a complex activity that not only depends on the engine load but it also depends on how the engine is used.

This might be kinda out of place, but the rally cars retard their ignition timing 40deg on turns and causes the combustion to occur in the exhaust manifold to keep the turbo spooling. Weird, but this is to point out that the ignition settings depend on the usage.

hmm im not really gonna give you a lesson in spark advance but more advance does not mean more power. and thats most of the time.

[smufguy]

hmm im not really gonna give you a lesson in spark advance but more advance does not mean more power. and thats most of the time.

i know thats why i said, it depends on engine load and how the engine is used. You dont need to give me a lesson tho, i already took it

[Sean]

i know thats why i said, it depends on engine load and how the engine is used. You dont need to give me a lesson tho, i already took it

actuall load has very little to do with the actuall spark advance. it has alot more to do with combustion chamber shape,cam timming,quench area,plug position,induction,and exhuast routing and pipping. the optimal spark advance for any given load is far mroe dependent on these then load. and how are you defining load. as a percetage of cylinder filling based on throttle angle or amount of Tq produced. in reality cylinder filling and the things i mentioned above have famore to do with spark advance then the actuall work load on the engine.

as for spark advance it self. think of it as a hysteresys. i always forget how to spell that word. the process of combustion in the cylinder is always ready to take place. the spark simply acts to tip the reaction at an ideal time. but if the variables concering cylinder filling were to change even without spark you could still have combustion. although it would be rapid and uncontrolled. hence isooctane in gasoline. but that a whole different topic.

[smufguy]

i was just generalizing the whole engine load which was a combined term of the engine type, chamber charecteristics, velve geometry, piston area and shape, and all the other stuff. I used engine load to say in simple words of how everyone is used to referring an engine running condition. Its true what you said about combustion without a spark, adiabatic compression or detonation as we know. also you know about diesel engines, they are controlled spontaneous combustion engines but dont use gasoline obviously.

You are an ignition god and we know it sean

[Sean]

i was just generalizing the whole engine load which was a combined term of the engine type, chamber charecteristics, velve geometry, piston area and shape, and all the other stuff. I used engine load to say in simple words of how everyone is used to referring an engine running condition. Its true what you said about combustion without a spark, adiabatic compression or detonation as we know. also you know about diesel engines, they are controlled spontaneous combustion engines but dont use gasoline obviously.

You are an ignition god and we know it sean

well trying to simplify a topic as complex as spark advance and its deliterious effects on both TQ production and resistance to preignition,detonation would be both silly and reckless. there are many point at which the return for more advance actually becomes small then the potential for a gain in output. ive had this argument with the engineers at lingefleter engieering many times.

the piont reall is that the a20a does not particuallary care for lots of advance. secondly it doesnt need it. very efficient chamber. it does however enjoy having the compression ratio ( dynamic) riased by additional fueling and having some spark removed. for those of you reading tjhis in laymans terms running a tad rich 12.2:1 at around 29btdc total with all the adavance in aroun 3500rpm with most of the stock cams. this will net an improvement of around 10-15hp depending on the condition of the engine. it would seem od that is would perform so well but infact the actually afr isnt really 12.2:1 its actuall right around 12.8:1 but due to the overlap in the stock camshaft etc etc etc plus the effect of reduced timming most widbeand will observe this AFR. gotta remeber spark advance will have a function of AFR shift as observed in terms of exhuast content based on spark advance.

[smufguy]

lingenfelter engineering...................:: drools ::.................. oh cool stuff Sean. so lemme ask you this, so for our cars, stock motor can i have full ignition adv and run 43psit of fuel? what adv would be best and at what pressure? like resonable i mean.

[Sean]

lingenfelter engineering...................:: drools ::.................. oh cool stuff Sean. so lemme ask you this, so for our cars, stock motor can i have full ignition adv and run 43psit of fuel? what adv would be best and at what pressure? like resonable i mean.

look up i already told you thre best afR and total advance

[smufguy]

look up i already told you thre best afR and total advance

since i dont have a af gauge, but just a AFPR and a fuel press gauge, how am i supposed to know what psi of fuel corrolates to what ratio u mentioned?

[Sean]

since i dont have a af gauge, but just a AFPR and a fuel press gauge, how am i supposed to know what psi of fuel corrolates to what ratio u mentioned?

how am i supposed to know that ? i just program my AFR i dont use a fpr.

[PhydeauX]

You'll need a wideband sensor if you want to read afrs in that range accurately.

andy

[smufguy]

well i used full advanced and running 45psi right now. dont have detonation or overheating, also could be cause i got redline stuff in there so the cylinder head temp seems to be like it used to be. Well this is just ghetto, but it does pull harder than before when i was only running 37psi. Thanks anyway tho sean, ill keep what u said in mind

[SpeedySweetie]

Thanks everyone, for the great advice! I've decided to stick with my stock injectors, and work with the timing and suspension setup. I'm also using one of those cheapy resistors that you stick into the IAT sensor that advances the ignition timing, and it seems to give the car a little more torque. BTW, PhydeauX, I'm a 100% "she"! and you're absolutely right, my poor little a20 is going to be WOT (or what we call WFO) for 20 laps around a 3/10 mile circle and a fpr should help. I ran one on my Dodge and it was nice to be able to adjust for environmental changes. Well, I'm owt...gonna go install my new iridium plugs & 9.5mm silicone wires! Check pix & progress on my website (www.2chixracing.com). XXX's & OOO's