turboant

I just got done rebuilding my motor, its a B18a with eagle rods, and srp pistons with acl rod and main bearings,and i got a B16a head and i got a t4 turbo boosting like 8psi, And with 450cc DSM injectors with inline resistors, with a safc2. I hear a little knowcking sound until i get to about 2 1/2 thousand RPM's. Is that good or bad???? or is that just because i still have to break the motor in????

DaX

iTrader: (1)

You are already boosting and haven't fully broken in the motor yet?

turboant

yup i got like 35miles on the motor

G"UNIT

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboant &raquo;</TD></TR><TR><TD CLASS="quote">I just got done rebuilding my motor, its a B18a with eagle rods, and srp pistons with acl rod and main bearings,and i got a B16a head and i got a t4 turbo boosting like 8psi, And with 450cc DSM injectors with inline resistors, with a safc2. I hear a little knowcking sound until i get to about 2 1/2 thousand RPM's. Is that good or bad???? or is that just because i still have to break the motor in???? </TD></TR></TABLE>

what kind of clutch you have?
mine does the same thing and it was a stock motor. i hvae a 3 pux unsprung clutch in mine. i think it was that chattering at idle becuase that sound has been in my last 2 motors.. but who knows.. the bttom ends never broke on them.

turboant

i just got the stock clutch for now

earl

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboant &raquo;</TD></TR><TR><TD CLASS="quote">yup i got like 35miles on the motor</TD></TR></TABLE>
too much piston to wall clearance...keep boosting without tuning and you will be rebuilding again. You may have hurt the pistons already.

turboant

what do you mean too much piston to wall clearance

slowpokesi

is it coming from the block or the head, it could be the valves ticking, my b16a is loud clicky clicky clicky

earl

cylinder bore size minus piston size = piston to wall clearance

turboant

it bore 20 over and i got b16 eagle rods in it so i can get the low comp. so your saying that my piston is rubbing on the walls

adeihl

no he is saying your piston wall clearance is to much and yoiu pistons are esentially rattling in the cylinder

Liltrix

In other words the cylinder bore is probably larger than it should be for that size piston or your Machinist needs to get some training from Earl

boosted_dc2

are the pistons slapping the head??

Landon

99B16Si

whenever u put in an aftermarket piston u need to set the piston to wall clearance accordingly every piston has different specifications.

and if youre using SRP's like u say they have a pretty high silicone content which keeps them from expanding as much as other forged pistons thus needing less piston to wall cleance than lets say regular JE's

an easy way to tell if u have too much piston to wall would be excess noise at cold start then quieting down when the motor warms up

1point7T

hey turboant, i'm not trying to jack your thread or anything.. but i'm having the same issue that you are..

a low knocking sound at idle that speeds up with rpms, then goes away after ~2K rpms..

mine sounds the same whether it's cold and I just started it, or it's been running for an hour..

i've got a b17a1 block, b16 crank, eagle rods, arias 9:1 pistons, and honda 'green' bearings..

i'm 99% sure it's not related to the clutch (action 2md) or flywheel (streetlite), since it doesn't sound any differently with the clutch pedal in, or out of gear.

i'm going to plastigauge the rod bearing clearances tonite/tomorrow morning to see if that's an issue.

havok hybrid

i have a ls vtec with cp pistons and eagle rods... and it does something close to what you guys are talking about.. BUT.. i think my issue is with my injectors.. i hear a click/ knock at low rpm.. but that is becuase i have 1000 cc injectors and there trying to fire so slow.. that it makes a lot of noise between all 4 of them

Try in figure out if the click / knock is coming from the bottom end.. or the head... or injectors.. or timing belt area.....

DONT BOOST A UNTUNED MOTOR!!!!!! ....

dennis

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1point7T &raquo;</TD></TR><TR><TD CLASS="quote">hey turboant, i'm not trying to jack your thread or anything.. but i'm having the same issue that you are..

a low knocking sound at idle that speeds up with rpms, then goes away after ~2K rpms..

mine sounds the same whether it's cold and I just started it, or it's been running for an hour..

i've got a b17a1 block, b16 crank, eagle rods, arias 9:1 pistons, and honda 'green' bearings..

i'm 99% sure it's not related to the clutch (action 2md) or flywheel (streetlite), since it doesn't sound any differently with the clutch pedal in, or out of gear.

i'm going to plastigauge the rod bearing clearances tonite/tomorrow morning to see if that's an issue.</TD></TR></TABLE>

Similar situation with mine...F22b2, CP pistons, Eagle rods, ACL bearings

1point7T

i know it's not injector tick, it's more distinct, and lower pitch than that..
also, i've used a dowel rod, and a stethoscope to listen on the entire motor, and it is very audible when holding the dowel to the corner of the bottom of the block, but it's just as loud on the back plenum of the intake manifold..

standing above the car it sounds like it's coming from the back of the motor, but it's distinctly audible from inside the car with the windows closed, or outside the car..

this is really annoying for a fully built motor..

B18C1CYA

was any thing removed from the block or head that would change your deck hight?

turboant

how long have you guys been driver with it making the knocking sound

G"UNIT

mine only does it idleing at low rpms like 800 to 1000k and after that it goes away.

VanHonda

Like others have said, it is more than likely piston slap.

1point7T

i realized today that my '00 Si makes the same knocking sound, but it's almost inaudible when compared to the GS-R. I drove the Si around for a while to make sure the motor was warm.. the sound is still there when warm.. it might be quieter at that point though..

i'm up to 300 miles on the motor.. i noticed the sound at about 50 miles. i can't honestly tell you if it's any louder or not..

it's not slapping against the head.. the deck height wasn't changed..

Bailhatch

turboant, post up your piston to wall clearance if you have it.

turboant

i just did a Compression Test and it reads #1 175 #2 155 #3 140 #4 140 so does that mean the #1 piston is messed up