engine knock with ultimate

IpHoOnDyou

New member
ok so here's the deal i have a stock 1992 and it has exhaust and an RPM intake. I took it out for a couple miles yesterday and noticed upon reaching boost my knock sensor in the ultimate itself flashes 3 or 4 times real fast but it wont do it after that, only when i start to boost just a couple quick flashes and then none.
what i have done
intake gaskets upper and lower
ultimate chip guage style stock inj
3bar map
RPM intake
proper ac delco plugs wires cap and rotor(all info from sytyarchives)
set timing to zero spark advance dissconected, then pluged in and checked again

So i guess my question is that....... Is a little bit of knock ok on these trucks? I also gapped the plugs to .32
 
Re: engine knock with ultimate

Are you running a converter? Is your intercooler pump working? Just a couple of thoughts since your truck seems to be stock. If it only fllickers a couple times while starting to build boost, sounds like a little boost spike. Are you running a aftermarket boost guage or just the stock one. You need a accurate guage or maybe datamaster to see what is going on when it does it. Maybe check your wastegate to see if it moves freely and the vacuum lines on the solenoid.
 

IpHoOnDyou

New member
Re: engine knock with ultimate

Do you still have the stock fuel pump and req ?

As far as I know the pump is stock?! I have never dropped the tank so I really cant give you an honest answer on that. But the fuel reg is also stock and looks to be almost new.....what im sayin is that it was very clean compaired to the rest of the engine bay. To answer the other guys questions, Yes it has a converter(not for long), yes my intercooler pump is workin, and as far as the wastegate working im not 100% on that. I was not sure when I got the truck if it was working so........ I unbolted it from the turbo and was able to move the gate in the turbo itself but did not see the rod move into the plunger of the wastegate itself. I would it is hard to push with your hands tho, Also I have an aftermarket boost guage but i am waiting on RPM to send me the very nice brake booster hose with the flange on it. And with having the ultimate my boost readings on the inaccurate gauge to begin with are of course way way off
 

IpHoOnDyou

New member
Re: engine knock with ultimate

Seems just a bit big.

Need to use a scan tool.:tup:

That is what Mike Lee at sytyperformance told me to gap them to.......... Remeber stock truck becides intake, ultimate, and exhaust. If this gap is incorrect what should I gap them to?
 

SY2455

70's Veteran
Re: engine knock with ultimate

If the truck has the stock fuel system, Then there is your problem. With the Ultimate should be run with a 255 fuel pump and a AFPR set at 45 psig min with the vacuum line plugged.
 

It's just a six

Super Member
Re: engine knock with ultimate

That is what Mike Lee at sytyperformance told me to gap them to.......... Remeber stock truck becides intake, ultimate, and exhaust. If this gap is incorrect what should I gap them to?

I was just making fun ,,, .320"/that's more than 1/4" ,,, I know you ment .032.

How much boost are you trying to get to? If it's above 14 or so, a stock fuel pump would be hard pressed to fuel much more than 14 PSI of boost pressure.
 

IpHoOnDyou

New member
Re: engine knock with ultimate

If the truck has the stock fuel system, Then there is your problem. With the Ultimate should be run with a 255 fuel pump and a AFPR set at 45 psig min with the vacuum line plugged.

what do you mean vac line plugged? on the reg?
 

IpHoOnDyou

New member
Re: engine knock with ultimate

I was just making fun ,,, .320"/that's more than 1/4" ,,, I know you ment .032.

How much boost are you trying to get to? If it's above 14 or so, a stock fuel pump would be hard pressed to fuel much more than 14 PSI of boost pressure.

HAHA know i get it yeah I had a blond moment i guess LOL, so yeah i guess it walbro time, so befor I get the new reg and the pump would I be safe lets say running 17 or 18 psi?? or should i just leave the ultimate at the lowest setting?
 

SY2455

70's Veteran
Re: engine knock with ultimate

what do you mean vac line plugged? on the reg?

On the fuel pressure req top you will find a vacuum line that gets unplug on a adjustable req. You will need to cap this vacuum line and then adjust your fuel pressure with a gage connected to the testing port on the fuel rail. After you adjust the pressure, then you need to reconnect the vacuum line and remove your testing gage.
 

SY2455

70's Veteran
Re: engine knock with ultimate

HAHA know i get it yeah I had a blond moment i guess LOL, so yeah i guess it walbro time, so befor I get the new reg and the pump would I be safe lets say running 17 or 18 psi?? or should i just leave the ultimate at the lowest setting?

Do not drive your truck without the pump and AFPR with the Ultimate.
 

IpHoOnDyou

New member
Re: engine knock with ultimate

Do not drive your truck without the pump and AFPR with the Ultimate.

Will it blow it to all hell? Im just really confused now..... I have the original instuctions right in front of me and no where does it say to run a walbro pump or an adjustible fuel reg?? As far as I can tell you buy the ultimate and but a 3bar map and your ready to go? I doesnt even say it on sytychip's:squint:
 

SY2455

70's Veteran
Re: engine knock with ultimate

Do you remember reading this part?

The advantages:

FUELING- A 3 bar chip now has the potential to add fueling at boost levels
greater than 14.7psi. However, the stock setup is limited as the stock
injectors are nearly maxed out (100% duty cycle). On the 3 bar Ultimate chip,
the fueling is slightly leaner than stock, so a higher base fuel pressure can
be run to deliver a bit more fuel at higher boost levels.

You can only run a higher base pressure if you have a AFPR and a pump that will handle it. I just don't want to read about you blowing it up.
 

IpHoOnDyou

New member
Re: engine knock with ultimate

You also need to read the 1st paragraph again. Look at the last sentence. The pump is security, the AFPR is a must because you will not get 50psig out of the stock fuel pressure req.

http://www.sytychips.com/Ultimateinstructions.html

Ahhhh im glad you have better eye's than mine:lol: So I know you said not to drive it....... but what if i drove it and just didnt cross into boost ALL the time. Because I would need to get this to my shop AGAIN. But I should also mention when i bought this truck from NY i drove it all the way back to IL and when i got home I noticed the vac line off the back of the upper plentum that attaches to the fuel reg and the map........yeah.....that line was rotted right off the upper plentum, so I should be ok to drive it to work as long as im not boosting the shit out of it right.... Again i apologize i didnt notice that on the web site:lol::lol:
 

SY2455

70's Veteran
Re: engine knock with ultimate

Ahhhh im glad you have better eye's than mine:lol: So I know you said not to drive it....... but what if i drove it and just didnt cross into boost ALL the time. Because I would need to get this to my shop AGAIN. But I should also mention when i bought this truck from NY i drove it all the way back to IL and when i got home I noticed the vac line off the back of the upper plentum that attaches to the fuel reg and the map........yeah.....that line was rotted right off the upper plentum, so I should be ok to drive it to work as long as im not boosting the shit out of it right.... Again i apologize i didnt notice that on the web site:lol::lol:

It may be ok to drive it to your shop, but make sure that you drive EASY. Hopefully you have another car/truck that you can drive until you get it fix. You don't have to apologize to me, I'm just trying to help you out :tup:.
 

IpHoOnDyou

New member
Re: engine knock with ultimate

It may be ok to drive it to your shop, but make sure that you drive EASY. Hopefully you have another car/truck that you can drive until you get it fix. You don't have to apologize to me, I'm just trying to help you out :tup:.

Thank god i have a brother with a Sy:tup:, He recently ordred an RPM fuel reg and the walbro 255 intank pump. And he is being nice enough to loan me them till I can order them. So when I do this drop the pump in ect..... To set the fuel pressure do it with the vaccum line disconnected? And to what pressure do I need to set it to? I believe you said 50psi at idle
Thanks again
Steve
 
Re: engine knock with ultimate

50lbs would be a good start. Back when I was running just the ultimate and exhaust only, a fellow forum member did a couple logs for me and my injector duty cycle was at 137 with the fuel pressure set at 45. Just by raising my fuel pressure up to 55lbs my duty cylce dropped to 111.
 

IpHoOnDyou

New member
Re: engine knock with ultimate

50lbs would be a good start. Back when I was running just the ultimate and exhaust only, a fellow forum member did a couple logs for me and my injector duty cycle was at 137 with the fuel pressure set at 45. Just by raising my fuel pressure up to 55lbs my duty cylce dropped to 111.

I am gonna hook up my tech 1 tonight and let you guys know what i find. Thanks for all the help guys
Steve
 
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