D21X

hey whats up everyone! i have a 91 accord specs:
F22a1 engine automatic
2.2L, 8.8:1 compres, 125hp, 130lb-ft torque, 140k miles, 6200rpm redline, might need new piston rings, still need to do compression check.
turbo parts consist of:
2nd Gen DSM manifold
14B turbo
1st Gen DSM BOV
SMC fuel management
450cc DSM injectors
1st Gen SMIC
Piping
Tranny Cooler

i want to go turbo but i still have some questions. i've been lurking everywhere to find info but still have some questions on some.

i've been researching the DSM turbo on fitting on to my engine with mods to the manifold, like redrilling some holes so it will align with my engine. i know i have two options on turbos, the T-25 or 14B. they both have internal wastegates set at 8psi. the T-25 i know will have very good spool up while the 14B will not because the wastegate starts to open up at 2-3psi from what i have read.

i will be going with the 14B because my experience with a d16 vtec with that turbo shows that the top end will die out. for my accord i am trying to accomplish quick spool for good low end and some high end. with the 14B will i be able to accomplish this???

i will have to lower the wastegate boost to 6-7psi to be safe. or do u think the stock 8psi of the 14B is safe. i can't risk boost spiking, which will force me to lower the boost to 6-7psi.

i know of 2 ways to lower boost for the 14B. i have read the threads and its either with the carb spring or lengthing the actuator. using the carb spring, i dont feel is reliable. after absorbing heat wont the spring's metal expand, therefore the spring will expand more giving less boost which would be inconsistent. using the carb spring can i still use a manual boost controller???

with lengthing the actuator, for the 14B the wastegate opens early at around 2-3psi so the wastegate will open even sooner, therefore producing turbo lag. on my f22a1 will i notice this lag even tho my engine is slightly larger???

other than those two ways is there another internal wastegate or actuator i can simply swap to give me my ideal boost??? thanks!!!!

twkdCD595

you can run 8 psi as long as you make sure you a/f is not extreme either way.

thats a very small turbo for the 2.2 but with the lower redline the accord has... it would probably work out alright. It is gonna run out of wind on the top end a bit but you seem to know that.

teamlegacy

From what I've seen the 14b has a quicker spool and is capable of 20+ psi like on the 1g DSM cars. The 2g manifold will fit the t25 and the 1g manifold will fit the 14b. As long as you get the air/fuel tuned correctly, you can run safely 6-8 psi daily and maybe 9-10 for the track. But I definetly suggest, bigger injectors, bigger pump, and a standalone unit.

D21X

anyone else???

filthy scarecrow

if you use a pressure relief valve (grainger valve, http://www.mcmaster.com part# 48935K25, $7.33) between the boost source and the wastegate, it won't see boost until 6-7psi (whatever you have it set at) so it won't start creeping open at 2-3psi. it'll stay shut until the pressure valve opens and lets it see boost. this'll help it spool faster.

i believe both gen dsm turbos use the same flange, so the manifold should work for either turbo..

D21X

ok so from what u're telling me i can use this pressure relief valve, so then i can just set the wastegate to less than 6-7psi like say 4psi, by extending the actuator.

doing this, the pressure relief valve will not send the wastegate any boost, when i hit 6-7psi the pressure relief valve sends the wastegate the boost, therefore the wastegate will open right away. the wastegate will then not allow me to go over 6-7psi because i have it set at 4psi?

if i had the wastegate set at 8psi without modifying the actuator it will still go to 8psi even tho i have the pressure relief valve installed right???

did i correctly understand how the pressure relief valve works??? thanks!!!

XDEep

mcmaster never ceases to amazing me

filthy scarecrow

yeah, you got it right..

only issue is that wastegates dno't work on boost alone, they also work based on exhaust pressure. there is a certain amount of exhaust pressure pushing on the wastegate puck from the turbine side as well as the boost trying to open it. if you extend the arm too much, the pressure will overcome the spring in the WG and it will open. the turbo I dodge cars are notorious for this. their WG's open at 10psi whether there is boost connected to the actuator or not. the idea is to set both to about the same pressure so that the WG stays closed as long as possible.