Jdm b18c into em1 ECU and MANIFOLD question

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Okay guys, I've seen similar thread to this but not quite what I'm looking for and I am a noob so please take it easy on me :shrug2: ... I have a USDM 00 Civic Si (obd2b) and my motor blew up, so I figured why not time to upgrade? Wanted to make OBD conversion as easy as possible on myself, so I ordered a JDM b18c GSR motor and p72 ecu from jdm-online (both obd2a), which is in the process of shipping.. This is my daily driver, so when it gets here I want to have everything ready for my mechanic and me so that we don't run into any problems. I also have obd2a to obd2b conversion jumper harness ordered, but the website I ordered my motor from said nothing about a wire harness included in package... I have included the URL for the motor I bought.

JDM Honda | Acura Integra B18C GSR DOHC VTEC '96-'00 - B Series - Honda - JDM Engines - JDM Online

1) With the above parts given, do I have everything needed for a compatible plug-and-play swap and should all the wires hook up?

2)Given that I also bought JDM ecu, are there any major things I need to change out? ie. sensors, etc.

3) Will my AEM short ram intake hook up to the gsr motor?

4) Will my b16 header (cheap pace setter) fit the b18c head and also clear the longer block/oil pan?

Like I said I really want to know necessary information and have all the parts ready for my mechanic when we go to swap... ANY INPUT IS APPRECIATED!! Thank you
Since you are using the JDM motor and JDM ECU it will be fine the B16 harness will have some extra plugs because the JDM motor will not have some of the sensors the USDM has. The B16 header is to short and will most likely hit the oil pan you will need a B18 header. Your intake AEM intake will work but you will need an elbow coupler to make it work.
The header should bolt right up. Intake should work fine too and yeah, same harness will work with new motor but there will be extra plugs...
You're also going to have to use the IAB plug from the JDM GSR harness, and wire it into your USDM B16A2 harness.
I am pretty sure B16 headers are shorter than B18 headers because the B16 block is shorter. You can use a B18 header on a B16 but Im pretty sure it does not work the other way around. I could be wrong though. Oh you either need to reuse the B16 AIT sensor and leaft the Type R one in the manifold or lengthen the B16 AIT wiring to reach the one on the B18. I just used the Civic's AIT sensor on my swap.
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Okay - a little update. I had a professional import performance shop do the swap. B16 header did not clear the oil pan as you guys suggested, but lucky for me a JDM ITR header was included, which worked out for the best. The head guy strongly suggested a hondata tune, so the butterfly secondary was disengaged. One thing to note was the car was the victim of HEAVY water intrusion - yellow grim caked throughout entire motor!! Either the tsunami or careless pressure washing was to blame. Either way I went ahead with the preventative maitenance - valve lash and clearances set to spec, head gasket change, oil pan cleaning, motor thoroughly flushed, water pump/ timing belt and tensioner replaced, etc. So after all that and the tune the car ran AWESOME for like a day, with the exception of a loud chatter - sounded just like a diesel motor! So the head guy, Corey Parrish of SlowMotion in Sunbury, OH (VERY VERY knowledgable man) thinks it is very possible that it is bad LMA hitting the rocker arm, with slight possibility of bad internal bearings.... and said to get it in to replace LMA as soon as I get the money. However, upon startup the very next night, I immediately noticed a lopy idle - dipping down to +/- 500 rpm. The performance decreased... felt like I was down about 20-30 hp, and VTEC kept engaging at inconsistent rpms (oil pressure related??), so I parked it for the night. The day after that, the idle seemed even lopier, performance WAY WAY DOWN... hard to even reach 60 mph and would NOT rev past 3500 rpm like it hit a fuel cutoff - I can only assume it is now in true limp mode. I'm having it towed back there today, and before it was picked up I noticed both the oil and coolant levels seem low, although the exhaust does not indicate a strong presence of burning either fluid, and it does not appear to be leaking under the car. Antifreeze is usual green and Oil does not appear milky. With the given information, any suggestions??? I apologize for the lengthy post, just want to give all necessary information...
Look into the H22 Type S LMA upgrade. They can handle larger cams and is way cheaper than buying ITR or new GSR LMA. I did it to my Vtec head and it works great. Sticking LMA is really common on older motors or motor that have sat for a while. HHmmmm didnt I say the B16 header would be too short and hit the oil pan, B16 block is shorter that all B18's. Since you have Hondata get it tuned and have the tuner turn on the GSR intake mani valves back on so they work, you will get some really good low to mid range power.
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Yeah some of the guys at the shop were suggesting h22a LMAs, much cheaper! Yes you did, very good call on the header.. it was a blessing in disguise though because I'm pretty sure the b16 header, even aftermarket trim, would still hamper exhaust flow out of the b18... as the ITR header piping appears larger in diameter. Also, do you think the current awful performance (if you can call it that) of the car is a direct result of the bad LMAs? Ran great after the tune.. very pleased with car with exception of the LOUD diesel noise. Next night it idles funny as hell... almost sounds like it is going to die and slight decrease in performance, also engaging vtec at inconsistent RPM point... day after that it barely runs at all and cuts off totally at 3500 and got slower by the minute

SO.... Bad LMA > Rattles so bad it affects crank sensor > Triggers ECU to run in true "limp" mode .. (best conclusion I could think of w/out testing the car that is now at the shop)

BUT - Why is it idling sooo lopey ... camshaft damage?

Thanks again.........
Oh, and I believe the tuner disabled the secondaries (now always open) when he changed the power band and raised the VTEC engage point to 5250 +/- ... very smooth power delivery, still has usable street torque, and great gas mileage. Still pulls very nicely off the line and strong 5th gear pull without use of the dual-stage manifold. However, I must say that is a brilliant design from Honda.. just not necessary for my current setup
Ok few things. 1 the LMA will not cause the motor to run badly just noisy so there is something going on. 2 you want the GSR intake valves to work not stay open all the time, you will get some really nice low end tq out of it. Best stock mani IMO is the GSR because the the dual runners, on a stock motor keep them on trust me. Most of the driving on a street car is in the low to mid range so that is where you want your power. 3 you dont want to raise the Vtec point lowering it a bit is most common. Mine comes on at 4800-5000 depending on driving condtions and Vtec should kick hard when it comes on. I would go back to the tuner/ install shop with these issues since you paid good money to have the motor swap it should be right and they should make it right.
Maybe I misunderstood him and he programmed the secondaries to changover the same time VTEC engages, because it does kick hard like my b16 did and not in 2 stages like the b18 did before the tune (cam then intake mani). Either way, he tuned the ratios to optimize the efficiency of my current setup, and it seems the VTEC engagement has been set at approx 5250 RPM, and looking at the dyno chart, that is the rpm where the torque and hp lines intersect... and the power curve is pretty linear. Regardless of the tune I trust his judgement on that because he is a well respected tuner in the state... but then again I can only base my own credibility on my modest noob knowledge lol - but definitely something to ask him more in depth about.

But as far as the shitty performance I am experiencing currently... like as in the car is barely drivable... it seems to me that it is running in limp mode (over used term on threads... I know), like barely making it to 60 and feels like a fuel cutoff at 3500 RPM. I read somewhere where bad LMAs can trigger a crank sensor and put it in limp mode...

At any rate, my plausible theories are...

A) the heavy, unnatural vibration or whatever from the LMA issue, triggered a crank sensor ...
B) a cam lobe was damaged due to lack of clearance from the LMA (both predisposed to damage due to prolonged exposure to water while sitting over the years).. which would explain why the idle is so damn lopey
C) Ignition components, namely parts of the distributor are not taking kindly to the relatively new MSD setup (I heard a cyp sensor can also trigger limp mode).. maybe coil is fried
D) Ecu somehow lost its tune over a day??
D) And the worst possibility is a bad main bearing :yuck: - which might explain the noise, inconsistent vtec engagement point, and might also trigger limp mode

Any of this sound likely to you??

Like I said, I'm a noob who is trying to learn as much as I can, and make this damn car decent and reliable without breaking the bank. I'll keep you posted on what I find out as I await a call from the shop........
Bad LMA would maybe trigger the knock sensor not crank sensor, not possible. You are best off going back to a stock ignition setup. the OEM ignition can handle 500whp no problem and upgrading from stock will not get you anything worth the cost. The ECU can not loose tune it is burned into a chip. Again you paid good money for a motor, to have installed and tuned now you are having issues. Take it back to the shop that did the work, they need to make it right.
Just got it back, idles super smooth now and purrs like a kitty. I meant to say knock sensor and managed to type 'crank sensor' in it's place. Regardless, you are THE MAN once again lol - the LMA did trigger the knock sensor, putting the car in limp mode. The cam timing was also thrown off about 8 degrees. They said ignition is functioning just fine. They modified and installed new H22a LMA, which we both agree is the logical choice.

And as far as deciding to install the MSD ignition setup - I know that it is by far not necessary for my application, but my b16 at the time (last summer) needed a tune up and was running rich as well. So my logic went as follows: Remembering back, I had a MSD cap, wires, and blaster SS coil on my old integra LS 3-4 years ago. And although it didn't necessarily gain ponies, it had noticably better throttle response and a few more MPG. Also felt like it woke up off the line, at low RPM. I figured why not do the same for the b16 and increase spark capacity with a 6a box at the same time. Looking back, it was definitely not worth the money, atleast when money needs to be spent elsewhere in the car.

Anyways, she seems to be in good and stable mechanical condition as of today. Runs pretty strong. On month old 89 octane, it dyno'd 163 whp for a tuned i/h/e setup... which seems on the higher side of most b18c with light mods that I've seen so far on the internet...

Now I just have a few fixes left before I can rest easy: Replace whiny wheel bearings, outer tie rods (and alignment), swap out the current skunk2 resonator (MOST UNBEARABLE EXHAUST RATTLE EVER) - then start paying down this heap of debt!!:wall:
Glad you are getting things normal. I was worried as I read about some water damaged motor :unsure:

Just as an FYI.....Honda no longer sells the older hydraulic style LMA's.

They are all spring style like the H22 and NSX LMA's. I bought some brand new in 2010
^ yep but they are still more $$ than the H22 LMA.

Wow must have been some pretty bad clatter going on for the LMA to trigger the knock sensor. My bet is that is was more the cam timing being off that was the issue. Glad to see you got it fixed. 163whp on a tuned GSR IHE is not to bad but should be a bit higher. My LS Vtec made 161whp with IHE and tune. The GSR has higher compression and slightly better cams, normally you get about 165-170whp with a tuned GSR, but LS Vtec makes more tq.
^ yep but they are still more $$ than the H22 LMA.

Isn't the only difference the little washer on the bottom of the LMA to make it the correct height?

I thought the H22's needed some spacer to work correctly in a B-series motor?

EDIT: I just looked it up on hondapartsunlimited.com

Same price.....$23 and some change a piece for either or.
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^ yep pretty much. But still B series LMA list at $33 and H22 Type SH list at $11.50 and ITR list at $48.03. The H22 LMA is still much cheaper and out performs the ITR LMA which is still the old hydrolic style and the spring style. All you need to make the H22 LMA work is a .030 I think it was (need to check my spares to verify)shim. A hardened washer will do the job just fine and is what most people use. I had some shims made out of hardened tooling steel. Mild steel washers will get squished and flatten out so dont use them.
Thanks again for the support fellas... Good to feel a sense of community in this day and age! But in response to the low whp comment... My tuner said the same thing. He said he woukd like to see it 8-10 whp higher than what it is clocking - but he also added that due to the nature of the higher compression motor, the month old 89 octane I had in it at the time of the tune was hiding some potential ponies. I'm not gonna make a butt dyno claim but it definitely seems to pull a little harder with fresh 93 octane in it :) ... What head did you have on your ls/vtec ??