Thread: Can't figure out this rattle!!!!

I just installed an L26 block with S1X cam, double roller, 90# springs, Gen V blower, SLP Headers, built tranny with 3.29 single chain, 4340 IS, pump shaft, and 2750 zzp converter.

all these parts were in another car of mine except the L26 and they all worked with no issues what so ever. they are now in a different car of mine that ran prior with no issues with a stock L67 and tranny.

The car rattles/clatters when going up steep hills in 4th gear, doesn't do it in any other gear, doesn't do it at wot, only in 4th gear going up a hill. noise is on the Passenger side.

I removed the SC belt, noise goes away 100%.

Replaced the Tensioner with a used, known good, tensioner and pulley, noise remained.

Replaced the smooth idler with a new idler, noise was reduced, but still present.

Replaced the grooved idler with a new idler, no change.

Blower is tight, coupler is good, no odd play.

even tried a different belt no help.

I'm out of ideas, and can't find anything else that would cause this issue.

ANY HELP is greatly appreciated.

IT ISN'T FROM THE BLOWER.


i stated, the blower is good and the coupler is good aswell.

i've had this entire setup other than the L26 block running before and no noise.

but you said that you removed the belt from the blower and the noise went away??
is the trans dipstick banging against the header?
could be the rotor bearings in the blower or the snout. make a video of it if you can

Originally Posted by QwikGT

but you said that you removed the belt from the blower and the noise went away??
is the trans dipstick banging against the header?
could be the rotor bearings in the blower or the snout. make a video of it if you can

which is why it's wierd. noise goes away with the blower belt off, but everything driven by the blower belt is good. I've driven cars with junk couplers and bad bearings and they will make noise in all gears aswell.

trans dipstick isn't even close to touching the headers

hard to get video of it since it will only do it going 60 mph up a hill. kinda gets drown out by road noise, atleast on my ****ty digi cam.

I'm all for trying a different blower, but i don't exactly have a spare gen v laying around.

my blower is noisy as hell. i think its ZZPs snout rebuilding. but im so used to it i dont even hear it anymore