knock sensor

by **SC V6** » Tue Aug 19, 2003 2:16 pm

the only problem w\ the numbers is that its getting too much fuel at lower throttle responces below 30% and im getting a WHOLE lot of blue smoke.. which is burnt fuel.. its really rich.. but Im going to see if I can't get that to go down by messin w\ my S-afc II... today just on the way home a impreza WRX pulled up next to me and tryed to play w\ me a little.. and I took off at the light, and at the end of my frist gear (even tho I spun threw the whole thing) I already pulled on him... so.. who knows.. my buddy should be re-building my tranny within the next year.. as soon as I get the $$$ for the kit.. so.. it will be fun once I get that all done and in there...
later
Scottthe only problem w\ the numbers is that its getting too much fuel at lower throttle responces below 30% and im getting a WHOLE lot of blue smoke.. which is burnt fuel.. its really rich.. but Im going to see if I can't get that to go down by messin w\ my S-afc II... today just on the way home a impreza WRX pulled up next to me and tryed to play w\ me a little.. and I took off at the light, and at the end of my frist gear (even tho I spun threw the whole thing) I already pulled on him... so.. who knows.. my buddy should be re-building my tranny within the next year.. as soon as I get the $$$ for the kit.. so.. it will be fun once I get that all done and in there...
later
Scott

by **808Camry** » Tue Aug 19, 2003 2:28 pm

Scott are you getting boost in first?

by **SC V6** » Tue Aug 19, 2003 3:01 pm

yes I get boost in first

by **all_red** » Thu Dec 04, 2003 10:18 pm

Ok.. after reading those 6 pages, my head is spinning, but I'll try to make my wording clear.

I'm gettin my SC installed soon and planning on going to 6psi within few months of that.
So when you go over 4psi you get a chance of blowing up your knock sensors unless you have ALL these below:
1)Headers.
2)SAFCII.
3)Dynotune for the SAFC.
4)Low compression heads (optional).

so first you get the headers and SAFC installed before you swipe in the smaller pully?

Am I right about all that? :-?

by **cdssolara** » Fri Dec 05, 2003 3:03 am

You might be OK with just the S-AFC and dynotune. What is the octane of the premium gas that you get in Texas? Our problem in CA is that we are limited to 91 octane pump gas. The heads were an option that was designed to allow us to safely increase the boost beyond 5.5 or 6 psi.

If you want even more power, go with the headers. You might want to consider higher flow injectors if you go that route, however. One thing always seems to lead to something else.

Website · by **kondo** » Fri Dec 05, 2003 6:13 pm

I originally started this thread a long time ago when I first got my check engine light. What happened to me was I put a 6 psi pully on my supercharger with No fuel management and was running 91 octane gas at the time. If you live in California only run 4 PSI unless you plan on getting some kind of fuel management sytem. The reason is the high compression of the engine and the 91 octane gas makes the engine knock and ping. You will most likely blow your knock sensors without some kind of fuel system if you just upgrading the pully. Trust me it is not worth it it cost me $800 dollars and a ton of time and frustration. There is not that much difference when you go to a smaller pully anyway I have the dyno sheets to prove it. 5.5 psi = 209.4ft/lb and 198.2 HP 4 PSI= 196.6ft/lb and 184.5 HP. Is 10 to 15 HP worth the risk of blowing knock sensors and possbly damaging the engine to you?

Nick

by **all_red** » Fri Dec 05, 2003 9:20 pm

well, down here i always use 93 octane all the time. Actually I just got my SC today. I'm planning on installing it in January. I'm also planning on going with 6psi by May AND getting fuel management device. I'm also getting the headers as soon as I have the money.
So you think I'd be fine with that? and I wouldn't blow my knock sensors? Would I have to install the fuel management device before swiping in the smaller pully?

Kondo, Well I've seen ppl on this forum getting higher numbers like 250FWHP, and I wouldn't mind going there. But I don't know why your numbers are low, because one guy got 162fwhp of his stock engine.

Website · by **kondo** » Fri Dec 05, 2003 11:46 pm

As long as you install the fuel management system before the smaller pully you should be ok. Just make sure that someone tunes the fuel system at the same time you install the pully.As far a my dyno numbers I have a auto so that is the reason why the numbers are a little lower. I also had my dyno done on a different kind of dynojet where they take the wheels off the car to dyno it (not the roller type), this also makes the numbers a little lower. The guy who did my dyno broke it down to me like this, "Any one can tune a car to make big numbers once on a dyno, my goal is to make as much usable power as possible when driving across the entire rpm range not just peak HP"

Congradulations on your supercharger you will come to find that it is money well spent.

Nick

by **cdssolara** » Sat Dec 06, 2003 1:06 am

With 93 octane gas, you could probably get away with a 6 lb pulley without having fuel management, but why would you want to? I agree with Nick about getting the S-AFC installed when you up the boost. As he said, it's very expensive to replace the knock sensors after the supercharger is installed. Besides the protection, fuel management will give you more hp, so it's really the way to go.

If you have headers installed, you will want to increase the fuel to match the higher airflow. The stock injectors just don't give you enough fuel, even with the S-AFC. You will want higher flow injectors, and possibly a higher flow fuel pump.

With your 5 speed and those upgrades, you should be able to get to 250 fwhp with no problem.

by **all_red** » Sat Dec 06, 2003 1:13 am

so what you guys are saying that I should have the SAFC intalled and dynotuned with the stock pully and then have it dynotuned again as soon as I install the smaller pully, right? and then if I get the headers (and maybe injectors and fuel bump) I'd need to dynotune it again, right?

Thank yall

by **cdssolara** » Sat Dec 06, 2003 1:25 am

That would be ideal, although you shouldn't need the S-AFC and dynotune for safety with the stock pulley. If you don't mind paying for the dynotune at that time, though, it would give you a good baseline for comparing your hp and torque with each upgrade. For the second and third upgrades that you mentioned, yes, you should definitely get the dynotune.

by **Hsakuragi** » Sat Dec 06, 2003 1:37 am

cdssolara wrote:.

If you have headers installed, you will want to increase the fuel to match the higher airflow. The stock injectors just don't give you enough fuel, even with the S-AFC. You will want higher flow injectors, and possibly a higher flow fuel pump.

so what if i don't upgrade to higher flow injectors? will there be any problems?

I have my safc ii, 5.5 pulley and headers & y pipe ready to install soon, so i just want to make sure it will be ok to the engine since i'm sorta a mad driver :drinking:

by **JoeB** » Sat Dec 06, 2003 8:14 am

You don't have to upgrade the injectors after those mods. I have an RMM Intake, JPP headers, y-pipe and exhaust and 6psi pulley and it runs ok on 93 octane but it would run even better with the correct fuel upgrade to balance the increased air flow. You do need a fuel controller to adjust the air/fuel mixture. The problem is, as you upgrade to the 5.5psi pulley, you are forcing more air. When you adjust for more fuel, the theory is that you start running the fuel injectors at a higher duty cycle than recommended. Then when you use larger injectors, you need a larger pump to keep up with the flow. I'm dropping my car off tomorrow with a guy that has done a lot of work with the Toyota 4-Runner 3.4L fuel systems that are Supercharged. He has run into the same issues we have and offers an upgrade. He's going to use my car to determine the correct parts, then offer the kit (Fuel pump, injectors and fuel controller). He said that he has had many people say they feel a lot of improvement in the low to mid range. I'll let you know as soon as it's complete. -JoeB

by **cdssolara** » Sat Dec 06, 2003 12:29 pm

JoeB wrote:You don't have to upgrade the injectors after those mods. I have an RMM Intake, JPP headers, y-pipe and exhaust and 6psi pulley and it runs ok on 93 octane but it would run even better with the correct fuel upgrade to balance the increased air flow. You do need a fuel controller to adjust the air/fuel mixture. The problem is, as you upgrade to the 5.5psi pulley, you are forcing more air. When you adjust for more fuel, the theory is that you start running the fuel injectors at a higher duty cycle than recommended. Then when you use larger injectors, you need a larger pump to keep up with the flow. I'm dropping my car off tomorrow with a guy that has done a lot of work with the Toyota 4-Runner 3.4L fuel systems that are Supercharged. He has run into the same issues we have and offers an upgrade. He's going to use my car to determine the correct parts, then offer the kit (Fuel pump, injectors and fuel controller). He said that he has had many people say they feel a lot of improvement in the low to mid range. I'll let you know as soon as it's complete. -JoeB

Joe, you may be correct, but that was not my experience. When I upgraded to a 5.5 lb pulley I also added an RMM intake and S-AFC, and then got a dynotune. Things seemed great at first, but within a few weeks I got a Check Engine Light and found I had blown the #2 knock sensor. It's got to be due to the 91 octane gas we're forced to use here in CA. Eric was using a similar set-up, but with upgraded injectors, the JPP headers and exhaust and the Split Second Fuel Management system, and I don't think he blew his sensors. The Split Second system also allows him to adjust his ignition timing, so maybe that's the secret. Anyway, my point is that even with 5.5 psi of boost you'll run the risk of blowing knock sensors, especially if you drive aggressively.

knock sensor

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