NewbVetteGuy
Well-Known Member
I'm wondering if Grumpy or any of the Grumpites have observed any back-to-back dyno results for a 4-7 or 4-7,2-3 LS-style firing order swaps for engines with TPI-style intakes.
I know the normal rule-of-thumb is that there's no to very little power to be gained and that the benefits are largely reduced harmonics and better cooling of cylinders 5&7, but after thinking about the fact that cylinder 7 has massive airflow challenges on all these types of intakes (including my beloved FIRST intake) -it seems like any additional competition for air to cylinder 7 is a really bad idea.
Because of the up-to-3 PSI of "boost" from the reflective waves at the torque peak, people can also run into knock / octane issues if "pushing it" with static / dynamic CR and it seems like keeping the heat even ESPECIALLY back on Cylinder 7 which is so far from the water pump could also be a benefit on a TPI-style intake.
I'm kind of regretting not learning about this sooner because I've already got my custom Mike Jones cam, but I'd still like to get a few more opinions; it certainly seems like TPI-style intake SBC could see the biggest benefit from a 4-7,2-3 LS-style firing order swap. (although it means there are ZERO off-the-shelf TRI-Y headers available for you then.)
Adam
I know the normal rule-of-thumb is that there's no to very little power to be gained and that the benefits are largely reduced harmonics and better cooling of cylinders 5&7, but after thinking about the fact that cylinder 7 has massive airflow challenges on all these types of intakes (including my beloved FIRST intake) -it seems like any additional competition for air to cylinder 7 is a really bad idea.
Because of the up-to-3 PSI of "boost" from the reflective waves at the torque peak, people can also run into knock / octane issues if "pushing it" with static / dynamic CR and it seems like keeping the heat even ESPECIALLY back on Cylinder 7 which is so far from the water pump could also be a benefit on a TPI-style intake.
I'm kind of regretting not learning about this sooner because I've already got my custom Mike Jones cam, but I'd still like to get a few more opinions; it certainly seems like TPI-style intake SBC could see the biggest benefit from a 4-7,2-3 LS-style firing order swap. (although it means there are ZERO off-the-shelf TRI-Y headers available for you then.)
Adam
