I got tired of giving lame excuses about not finishing my SC install because I'm too busy on weekends, so I left work at lunch yesterday and finished the job. I'm still checking EGTs and fuel pressure and tweaking the BOV adjustment, so I haven't done a WOT run to redline yet, but so far there is nothing but a smile on my face.

My setup: V1 blower, 3.25" pulley, 8:1 disk, Walbro 255lph pump in tank, Blitz DD BOV, one step colder plugs

I do have a few questions, though.

I did a WOT run yesterday and shut it down after a few seconds because I heard a rattling that sounded like detonation at about 4500-5000 rpm. EGT was only about 1300F at the time. When I let off the throttle the rattling continued, which makes me think it was just BOV noise and not detonation. Still, it was a bit scary and it's making me very cautious. I had the BOV adjusted with very little if any preload in the spring. What do you think? Just BOV noise because it was set to release pressure at a fairly low boost pressure? Is it possible to have detonation at 1300F EGT? (My EGT probe is a couple of inches below the front O2 sensor.)

How do you determine the optimal setting for the BOV preload spring?

 

I have the same problem with my Blitz Bov. At high rpms if you let off the gas you hear flapping sound. It might be that the BOV needs to be loosened.

 

Update: I increased the BOV preload and did a few runs during lunchtime. The scary rattle is gone, so it must have been the BOV releasing boosted air at a low boost pressure.

 

Congrats dude... Glad to hear your finally boosted. Now go drive that beast.

 

Congrats on the install!

1300 F = 700 C (my gauge goes by celcius) and at 700 C, you are not leaning out.

just wondering...do you have a full free flow exhaust? Because I dont and my EGT raises very fast. Probably because my cat-back is way to restrictive and it takes forever to release hot fart.

Do you have a boost gauge? what psi do you read at redline?

 

I do have a test pipe and cat back, but I uninstalled it and put the cat and stock b-pipe back on in order to pass inspection last month. That's going back on this weekend if it doesn't rain. Once I get the cat back on I'll have it dyno'd.

Last night I saw 9 psi at redline and the EGT was at 1400F . There was just a hint of raggedness in the firing, I think I may need to adjust the spark plug gap a couple of thousandths.

 

Oh yeah, I also have a Warpspeed mandrel bent y-pipe. My cat-back consists of a Stillen b (with resonator) and HKS exhaust. A pretty eclectic mix, but it works.

 

1400 is a good number with 9psi. Mine reads ~1400F at 6psi and I still have 500 rpm to the red line. so I cant boost for too long. I have a 3.33 btw....a bad 3.33 pulley.