Jeep 4.0 in 69 Barracuda
No worries mate!, I simply wanted to clarify the correct science of flow to those
following this so they have the ammo for their own projects. I agree the aesthetic
of the siamese dual system ala BMW etc. looks cool,as does the center exit,tho'
you will have to be creative w/ the spare well rite there. I would also second the idea
of making your own X-pipe as close to the frt. as poss., that would give you the 6
into 2 into 1 benefit and allow for the siamese system.
I didn't remember if the factory "manifold" was the shorty 6-2-1 unit, and planned
on cutting the "Y" section out, then putting flanges on the pair? Later units,and now
most aftermarket units come with flex/expansion sections as they were notorious
for cracking(sure you saw plenty of those), which will probably require some sup-
port bracket .
Glad you're moved in,I'm sure we've all done that for ourselves,friends and our
families.It can be extra challenging for us gearheads!!
To address the carb. & OBD I, carbs are probably more sensitive than any EFI
system,and OBD I all had closed loop adaptive learn. GM's Block learn mem.etc.
The GM's & Fords w/mass air systems have a definite advantage over speed den-
sity systems because they read actual airflow in,not calculate it.Also the OBD I's
Open loop idle AND WOT! This takes out adaptability when WE would like most.
The solution for us OBD I speed density users is the adj. fuel press. regulator.
Dial up the press. to compensate for flow improvements etc., and the closed loop
operation will dial back the injector duty per the O2 sensors input at normal drive
conditions, usually within it's parameter's unless you make a drastic change,read
big cubes, super headwork etc. The Grand National guys lived on that method w/
stock system use.You only need a scanner & watch O2 readings at WOT,then adj.
I'm excited to see your progress on this,keep us posted!! :coffee2: