Turbocharging a 5th Gen. Prelude

Since I've seen some members curious about boosting the lude, I've wrote up something that I think might help,

HERE WE GO! TURBOCHARGING THE 5TH GEN HONDA PRELUDE

If puchasing a 5th gen. Prelude, buy a base model and NOT the Type Sh! The reason is: 1)almost no aftermarket turbo kit support for the SH including the basic start up turbo kits. 2)Heavy,lack of space due to the atts assembly, and the system will start to fail after 250whp. I beleive some Type Sh owners have disconnected the atts and has been fine but dont quote me on that. But why put up with all the headaches! just buy a base model!

OK Now the you have purchased a base model! =)

Option 1: Boost the H22A4
pros: engine is already in the car
Cons: OBD2, Open-deck design, weak sleeves, ring landings, compression ratio.

If you plan on not building, purchase a kit that has AT LEAST has some kind of fuel management. This includes: upgraded fuel pump, FMU, Missing Link MAP and a "blue box" like the greddy piggyback unit or do the afc hack. Do I recommend any of this? NO! But it should get you by at 5psi of boost at the cost of no gaurantee on longevity of your engine. Some have been able to pull this off where others blew their engines and failed miserably shortly after.

Option 2: Swap JDM H22A or US H22A1 and boost
Pros: OBD1, Closed deck, availabilty on engine and parts.
Cons: Cost, weak sleeves, ring landings, compression ratio.

How to swap OBD1 H22 into a 5th Gen:
You must move the followings from the H22A4
a) Wiring Harness (OBD-II)
b) Distributor
c) Coolant Thermostat Housing
d) Oil Pump Housing
e) Crank Position Sensor and Top Dead Sensor (attached to OBD-II oil pump)
f) Exhaust header (JDM 4th Gen is different but you will be turbo anyways)
g) Intake manifold (if not using 5G IM, then move your fuel injectors over and get a 4G MAP sensor)
h) Knock sensor (BE VERY CAREFUL TAKING THIS OFF, THE CONNECTOR BREAKS EASILY)
i) Oil Pressure Sensor
j) Oil Pan & baffle
k) Oil Pan/Transmission Stiffener
l) Various gears from the timing belt side (crank gears especially - required for CKP/TDC sensors)
m) VTEC solenoid pressure switch (the connector seemed to be different on the H22A one)
This means you will still be able to run the OBD2 P5M ecu on this OBD1 H22 motor. As for turbocharging, pretty much what was covered with the H22A4 section. You could aslo invest in a good engine management for option 1 or 2 and your stock motor might have plenty of boosted life. More on engine management below.

Option 3: FULLY BUILT H22A,A1,A4!!!
Pros: FAST, RELIABLE
Cons: NOT CHEAP

The H motor is notorious known for weak sleeves and ring landings. This is the main reason why most Prelude engines fail when boosting.

You want to get the motors bottom end beefed up by doing this:
1)sleeved (golden eagle, darton etc)
2)rods(eagle,pauter,peak etc)
3)Low compression pistons(arias,mahle,JE etc..)
*lower compression is usually safer, sluggish but more power capability*
*Higher compression means easier to make and more responsive power*
*Higher compression also means tuning is CRITICAL. I find 9:5:1 is ideal*
4)engine/rod bearings(OEM,ACL,Clevite,King,Calico etc..)
5)balanced/blueprinted assembly

If you want to go all out, you may build the H22 head:
1)stainless valves(skunk,crower,farrera etc..)
2)springs(skunk,crower, etc..)
3)retainers(same as above lol)
4)Port/Polish/3angle valve job
*stock H22 head flows very well*
5)aftermarket cams (crower etc..)
*stock camshafts works very well*
*aftermarket cams is good if you want to make power at higher RPM's*

Engine management:AEM EMS Standalone fuel management or:
1) Convert to OBD1 by purchasing conversion harness and proper ecu. P28,P08,P72 are the few ecu's you may use. P13's does not have much support.
2) Decide if you want to use Hondata, Chrome, Uberdata etc..
3)Decide how much boost you are runnig. If thats 10psi or under, the OEM Honda MAP is fine. IF MORE, upgrade to GM 5bar MAP sensor. Part#12223861.
4) Decide your power goals and upgrade fuel injectors accordingly. RC and Precision make very good units. I recommend going big because the last thing you want is to run out of fuel on your tune. Any good tuner should be able to idle big injectors. 550cc would be the smallest i would run on a built H22 with an engine management that is why i left out DSM injectors as an option. 5th Gen Prelude's run saturated injectors. 750cc are the biggest saturated injectors available. Bigger injectors can be used but you must run a resistor box because they are Peak and Hold Low Impedence type. YOU WILL FRY YOUR ECU and risk BIG DAMAGE if you do not run a resistor box! You can find out how to wire up a resistor box here: www.hondata.com/techinjectorwiring.html

THE TURBO:
with a built h22 and proper engine management you have a wide variety of choices for turbo. Its up to you on how you want your car to drive and its characteristics. Most want quick spool for the street like the geddy 18g mitsubishi turbo or big power like the garrett GT40 series turbo. Its all on how you want it but as long as you have the right tune, you should be good!

MISCELLANOUS:
Be sure to have sufficient cooling. Upgrading to a C&R, Fluidyne, or KOYO etc. is a good investment for longevity on your motor. Run good oil and be sure to change it out frequently. I have found that 20-50w oil runs great on a boosted H22 but that is just my personal experience living in AZ. The lighter viscosity oils were just too thin and couldnt hold up. INVEST on a Electronic Boost Controller, boost gauge, oil pressure gauge, exhaust temp gauge, and air/fuel gauge. I dont know how accurate those air/fuel gauges are without a wideband o2 so having this can be optional. Also if you plan on keeping AC, be sure to put heat reflector wrap on your AC line by the turbo manifold. A filter on your turbo is a smart idea but if your setup is space constraint, you may use a mesh. There may be few more things I might have missed but just be sure to cover the little things to make your boosted H22 experience a better one.

That is ALL! Hope my :2cents: helped. Have fun BOOSTING THE H22 BECAUSE IT IS REAL FUN:lol: !
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the sleeves arent weak.