timing belt and afr issue... need opinion and expaination from u guys...

[zamrioo2]

1. how strong the oem timing belt...? i'm asking caused my b16a only pulls 156whp with 14.5kg torque and revving untill 8500rpm... powerband only at 7900rpm with b16b cams... wot at 12.8 afr... fr press at 38psi... i'm not the daily driving hi revving, once a week if any... can the oem belt support for my engine...?

2. recently i changed my oem header to jasma or what (just state jasma) and pull out my back muffler... really feels the reaction especially after the vtec engage n hi rpm and the sound also changed (a little bit kosong)... but after wot 3-4 running i felt to check the plug... what a surprise all plugs (irridium) were white... theoritically, why the plugs turn to white...? what i'm thinking is bigger header, less vacuum, less scavenge effect, combustion chambers become hotter, plug tips hotter n white... is there tend to detonate...?

after thinking and got advice from several friends n pomen i increased the fr press to 40psi then did several runs at wot... i checked the plugs again and found the no4 plug (cylinder beside timing belt) was dark brown but the others seem to be lighter brownish especially at no 1 plug (beside distributor) was the lightest (got little bit keputihan but not much)...

then i pulled-ip the fr press to 42psi and again it was happened as same as fr at 40psi... even darker brown but the no1 plug still like fr press at 40psi (fro my eyes)

should i increase the fr press more...? my wideband facility had been stolen and go to find wideband facility is a problem caused i dont have so much time...

thanks guys...

 

[hattech-v]

its normal when u change something that involving air-flow then the afr will be affected. the best way is to tune it using either piggyback or any other management...
sometime u can get correct afr before vtec but not after vtec engage if u do bump the fuel pressure using regulator...

about the hp n torque i think its normal for b16a with 16b cam...
n the oem belt still can supprt it..
but the aftermarket like power belt n toda give better than oem...

 

[shiroitenshi]

yeah, the oem belt can last with stock R cams, it's when you go for aggresive lobe cams like stage 3/specC/etc that reinforced timing belt is a required item. after all, the stock R uses oem belt only.

When using big headers and exhaust, it helps 'scavenging' (this is theory) and also frees up the engine breathing. Plonking in bigger headers and extractor usually results in the engine running a little lean. It's the same case with mine, and a few other cars as well.

For me, bumping up 0.5 bar fuel pressure from the stock 3.0 bar on the B16A was enough to get the plugs to be light brownish.

In any case, when one plug is different color from another, it's likely that your engine compression is different from one piston to another, and blackened plugs usually means that one piston is leaking, and engine oil managed to get in the combustion chamber.

It could also mean that your injectors are blocked and if one piston puts out more fuel than the rest, it could give richer fuelling for one of the pistons resulting in a darker colour than the rest, but that requires visual inspection or flow testing to know for sure. Since there's no flow test facilities, just check compression, then if that's not the source, then clean the injectors and see.

AFR wise, AFR is only as accurate as the engine's health. As I posted about it while ago, my leaking valves gives me 20.8 AFR at idle, which is totally impossible.. :P

AFR is a tool, but it's not the end all way to check engine health.

 

[J101]

1. the original timing belt is as strong as it is if you monitor your service log. you would probably need a strong-ER version, if you decide to pull higher than a stock b16a rev limit.

2. the 1st thing u should do after changing your extractor is to reset your ecu. let it run for awhile. when you have time, go for a proper wideband dyno and check your rpm ranges.

 

[eddie_vtec]

toda timing belt for b16b rm550...
power belt rm?

 

[hattech-v]

power belt RM480.

 

[chris2000]

eddie,

Need Toda Belt? PM me :)

 

[zamrioo2]

When using big headers and exhaust, it helps 'scavenging' (this is theory) and also frees up the engine breathing. Plonking in bigger headers and extractor usually results in the engine running a little lean. It's the same case with mine, and a few other cars as well.

ooowwwhhh... ok...

For me, bumping up 0.5 bar fuel pressure from the stock 3.0 bar on the B16A was enough to get the plugs to be light brownish.

3bar = ??psi... my matrics calculator at another pc... hehehe...

In any case, when one plug is different color from another, it's likely that your engine compression is different from one piston to another, and blackened plugs usually means that one piston is leaking, and engine oil managed to get in the combustion chamber.

It could also mean that your injectors are blocked and if one piston puts out more fuel than the rest, it could give richer fuelling for one of the pistons resulting in a darker colour than the rest, but that requires visual inspection or flow testing to know for sure. Since there's no flow test facilities, just check compression, then if that's not the source,

i suspect my compression also blowby or something... but mr shiro, after i took out my oem header, i found that my exhaust port at no3 wet (oily)... others seem dry... that's why i eager to check the plugs... but the prob plug was at no1 cylinder... as u said i'll try my best to check the compression 1st...

then clean the injectors and see.

how to clean the injectors arrr...? know the price...?

its normal when u change something that involving air-flow then the afr will be affected. the best way is to tune it using either piggyback or any other management...
sometime u can get correct afr before vtec but not after vtec engage if u do bump the fuel pressure using regulator...

i'm using vafc, easier... before e-manage but lazy la to get details setting... hehe...

about the hp n torque i think its normal for b16a with 16b cam...
n the oem belt still can supprt it..
but the aftermarket like power belt n toda give better than oem...

so many case oem belt memanjang n putus... that's why i ask...

about the exhaust port wet, is there any possible the valve seal kong...?

thanks...