Stock boost on a 21 cm housing, 5 speed 3.54? Reaction to basic mods?
with stock injectors and maxed out IP I was running 26psi, but it took forever to get fully spooled. That is with the timing advanced as far as it will go too, so that drops boost a little. Every truck is different though.
I was running that same setup last week before going to the 16cm with the 366 spring hell of setup it runs like a new pickup and i still have stock injectors. the reason for the stock injectors is gas in washington state is 4.75 a gallon
Trending Topics
When my truck was stock it also didn't see much over 14.5lbs.
That was a 92 with a 21cm auto and stock everything.
Thanks to wannadiesel I'm now seeing close to 47lbs
But with everything stock and my pump maxed out i couldnt get past 28 lbs of boost on it.
That was a 92 with a 21cm auto and stock everything.
Thanks to wannadiesel I'm now seeing close to 47lbs

But with everything stock and my pump maxed out i couldnt get past 28 lbs of boost on it.
Well, mine made a whopping 6 psi w/ a dirty air filter, 9 with a new BHAF, 12 w/ adjusted throttle linkage, 15 w/ fuel pin rotated to deepest point, and 19 w/ one turn of the fuel screw. I haven't touched the starwheel yet. It seems to have had the warranty recall injector pump put on it that some had, maybe thats why it wasn't so hot. It drives good now, I'm probably going to put a 14wg housing I have laying around on it. I've seen 15-16 on past stock 93's I've had w/ 18.5 housings, auto and manual, so I was expecting less on this one. On previous trucks I could get 29-30, but that was w/ a 4" exhaust, 366 spring, and more fuel screw. I haven't ruled out boost leaks, I'm going to build a leak checker soon. It doesn't smoke though so I doubt it. Just checking to see what everyone else was getting because it seemed so low stock, but it seems to react like every other truck to minor tweaks. What do you guys think based on your experiences, about right for those mods w/ a 5 sp and 21 cm housing?
16cm on my truck with 4 inch trans back made 25psi in forth and spooled alot faster, big difference over stock and mine was a 18cm.



