blown 350 wont pull over 4000rpm
 

ok heres the parts list.2010 block 030 over 4 bolt main ,9.5:1hyperuetectic pistons,world products sportsman 2 heads 72 cc ,es1095m cam450/461 lift 224/224dur, 1.6 alum full rollerrocker,hi perfomance welded push rods,gm performance nodular iron cast crank,kodiak alum headers, dean nickerson 750 carb. timming set at 30 deg all in, carb rebuilt blocked off power valve ,jeted 80s all around .best i can get is 4000rpm even when over trimed ,:eekdrop:b&m 142 blower

Prop pitch/drive ratio? The hyperpistons dont make the best blower pistons, I have broke the Gm zz4 ones in a non blown 350 small block so watch the boost, timing and don't torque load it (which is what you might be doing right now), Smittty

Ring end gap is critical on those hyper-u pistons . Too tight and you tear the top ring land off .

Compression seems high for a blower motor. Is it detonating?

How does the AFR look?

lower the sparkplug gap to .028 and see what it does..may be blowing out the spark..

If there is no PV in the secondaries, then the secondary jets need to be about 10 sizes bigger than the primaries. Did Nickerson build this carb for your engine????

I had a similar set up in a street rod and the engine pulled hard to 6000rpms+.

The cam is kind of small. I would think something closer to .490 lift would have a lot more power up top.

How much boost????

bought engine as is runs extremly rich with 90 in secondary,5 psi boost,cant find any info on cam. probly pull it out and go with a lt4 hot cam.

plugs are a nice tan color,look goood

no detonation,pops or backfires starts great ,idels great,runs great, just wont go past 4000

Prop? Drive ratio?