Stock boost on a 21 cm housing, 5 speed 3.54? Reaction to basic mods?
 

What should a 3.54 5 sp 4x4 get w/ a stock pump and a 21 cm housing?

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

Do you guys remember what your trucks boosted at stock though?

totaly stock 21cm should be around 15-18 psi. That was the standard for stock 21 IC trucks.

Mine has never gone over 14psi.

Close enough.[laugh] Is your fuel still set at stock and have you advanced your timing any?

To get my stock truck to hit 18psi I have to push the pedal as far as I can.

That sounds about right for stock.

Turned up, the thing will spool up just about when the pump defuels in 3rd, and about halfway up 4th and 5th. A smaller turbine housing does wonders even if you don't touch the pump.

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[laugh]

But with everything stock and my pump maxed out i couldnt get past 28 lbs of boost on it.

All stock, no pump or timing changes. I did get a 16cm housing which I hope to get on soon.

WHY did you buy the 16? Get 360 would be better with the 14 or 12 w/ gate 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?

I got it cheap and am just looking for a faster spool, it's a work truck that tows a lot of heavy loads so it will never get modified to the point of being a toy.

mine is the same "work truck" but its also fun to play with, i have a 14cm and it is great for towing but i didn't get one with a wastegate because they were too expensive.

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.