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Discussion Starter #1 (Edited)
Well i am doing a small build for my new beater. I dont see too many B21's being built or used anymore so i figured id let y'all know what im doing with my beater.

I acquired this gold 88 Prelude SI in a trade and i was actually already building this car for an old roommate. He saw my current DD and really wanted that so we traded with some cash on top of his end.
So i get this thing with a B21 in it. Ive already swapped the tranny to a D2j5 with a new stock clutch. That shit will be coming out very soon!
So i take a spare B20a head i pulled off one of my extra motors and decide to use that on it to boost the compression on it a bit.
I get a little shaved off the head and get the valve seats checked to make sure they seal and all that good shit. Seals are good so no need to do a full valve job.
I then get the head clean the shit out of it and ive ported and polished the intake and exhaust ports very nicely. I spent 8 hours in the head alone. Its of course port matched as well. I want to squeeze every ounce of power i can out of this beater. Now im working on finishing the intake manifold to be perfectly matched to this head.
Im halfway done then i'll get it all mounted up.
I will of course get pics later today for you guys.
I hope this thing does decent for the time ive put into it or im just going to boost another B21!
PIX 2 CUM!












 

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Discussion Starter #3
I just might. I have a stock ecu for now.
I want your Webcams! I only have a B18 intake cam and a B21 exhaust cam now.
And a DC header and 2.5 inch mandrel exhaust.
Im just using shit i have lying around for this. No real money will be dropped into this shit.
 

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lol, well i have someone saying they'll send money for the cams today or tomorrow. if they fall through and you have the funds, first 250 takes em.
but yeah, stock ecu should be ok, just remember to use 89 octane or higher at all times, and stock ign timing or 1-2 degrees retarded for safety especially considering the higher compression.

but its an 88, so im assuming you're using a pk2 ecu? which intake mani are you using?

im sure you saw my dyno comparisons thread, and how much power was gained through tuning, as well as reliability
 

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Discussion Starter #5
I saw and read through that bible length thread. And yes i of course know about the fuel upgrades and such. I put my cr at 10:6.1 with whats been done.
I am going to be using a PK2 intake manifold and a 4 wire o2 sensor. And yes a PK2 ecu as well.
I intend to get a baseline dyno on it when its put together and have everything in perfect spec.
 

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cams are sold.

but yeah, long as you're using the pk2 intake mani, you should be ok with the pk2 ecu. just be sure to use at least 89 octane or higher, and set the distributor timing according to spark plug readings. start with stock timing, and keep backing the dist off until the plugs look good; with the heat stripe being in the middle of the bend on the ground strap
 

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Discussion Starter #7
Yep got it. I learned the art of plug reading a long time ago by a genius.
Im going to throw in a set of colder plugs too and play with the timing a bit. I am toying with the idea of using a bit of nitrous. Well see what happens.
 

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intake matching

Just a little tip to get the best flow where your intake ports are on the outside instead of trying to match perfectly to the inlet manifold which is nigh on impossible without cutting it up and welding it back on, just open up the edges on teh inlet ports so that they make a nice bell mouthed entry, this really helps with flow just my 2 cents as i'm experienced with head work on an extreme budget as well as no budget!! Also just as another cheap mod you know you can use aftermarket inlets and have them machined to 30mm and use them as exhaust valves? Nice mod if you decide to go turbo as it can do with all the extra help getting the gases out quicker to spool the turbo up faster!! Also if you need more fuel in try adjustable fuel pressure regulator and bump up the pressure a little might make things easier FSE do one you can fit easily rather than the B&M which requires a bit of engineering to fit. Have on on my B20A in my 2G lude which just has bolt ons seems to work well only a few psi above normal but just helps keep things in check untill i get Megaquirt on for now. Nice work on the header 2.5" collector worth adding if you can to match the system will gain nice torque figures with that exhaust not that a B21 needs anymore torque lol!! Oh BTW notice the inlet manifold had quite a rough finish should just polish it smooth as because it's before the injectors no need to be rough like if it were carbs, just nice a smooth to get as much speed as possible, then after the injector same roughness as in your pics, you could also put the valves in a lathe and put the same finish on the heads as well worked well on my last engine doing that where i was running a super short runners on the intake. Also one last thing if you can get the seat on the valve matched to the seat in the chambers honda allways have too wide a seat on the valve head and this will disturb flow, easy to see as you'll see coke on the bit that's not seating on teh valve seat and the rest will be shiny if you get that bit cut away and have a back cut put on the valve you'll increase flow significantly. Also reshaping the valve guide and ramp in the inlet port and also the exhaust port and unshrouding the valves and making sure the valve seats are flush with the chamber walls will help too and you can do all this yourself if you have some spare valves and a steady hand!!
 

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Discussion Starter #10 (Edited)
Yeah everything is getting a glass smooth polish by hand.
I cant really do anything to the valves now cause the head is sitting on the block now and im just finishing up the intake manifold. BTW porting and polishing an intake manifold is a bitch for a B20a. B21 mani's are much easier!!!!!
I also will use my 62mm ported throttle body.
I already have a B&M but i will probably be getting some form of tuning for this.
I'll get more pix when im done with the polishing.

 

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Discussion Starter #12
Yeah i forgot about your build. But i may boost this thing if the numbers arent up to par. With all the head work put into it it should flow very well.
 

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B21 build

Well sounds like it should work well only thing holding it back a bit might be the cam specs but everything else is in place be interesting to see what you can get from a budget build!!
 

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Discussion Starter #14
For this budget build i'll be using a B18A intake cam and a B21 exhaust cam.
And some adjustable cam gears. The suspension is what im looking at now. I have some Tokico's i'll throw on it with some Weapon R circuit pro dual coils.
And my adjustable endlinks. Im still currently hand polishing the intake mani and finishing up the head. Maybe N2o?????
 

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ya its gonna be pretty much the same as mine except u will probably have a better flowing IM and head. im using 90-91 IM with a 62mm tb i got from u. ill have a teggy clutch and flywheel and accord 5th gear.

haha thats my old dc header too!
 

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ya its gonna be pretty much the same as mine except u will probably have a better flowing IM and head. im using 90-91 IM with a 62mm tb i got from u. ill have a teggy clutch and flywheel and accord 5th gear.

haha thats my old dc header too!
you also now have my web cams :)
 

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sorry man i dont have your accord 5th gear i almost got it from u but sold it before i could get to it haha. but i do have your pr4. dang dude anything else u want i got a pretty big parts pile right now
 

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no i dont have a 5th gear right now im gonna buy it new from majestic honda. hm idk about that trade just yet cuz im gonna get a teg flywheel and clutch cuz i need a clutch too
 
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