just wanted to know if anyone gets boost spike by running straight thru exhaust or open downpipe? only reason im asking is because this is the only thing i changed at the track and i went and put 2 rods thru the block! smashed the main bearing cap to bits and pierced my radiator with block shrapnel! new semi built motor is going back in soon just worried about it doing it again! thanks in advance for any help and looking! russell..

 

you will run leaner on open DP, but not that much leaner....you were probably teatering on the brink on detonation in the first place, sorry to hear that

 

When i had my 2.5 inch to 2.25 inch exhaust on my boost stayed at 12 psi. When i run open down pipe i find that it creeps to 15-16 psi.

 

I don't notice much difference at all on my wideband or boost gauge going from my straight through 3 inch exhaust to open downpipe.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beerbongskickass &raquo;</TD></TR><TR><TD CLASS="quote">I don't notice much difference at all on my wideband or boost gauge going from my straight through 3 inch exhaust to open downpipe.</TD></TR></TABLE>

a 3 inch exhaust is pretty big so no you won't notice much difference

 

thanks for the reply's after researching lots and lots it seems that some suffer and some dont with boost creep so i will have to keep my eye on it when rebuilt! thanks again