BA4Lifes B20A5 swap/build...

[BA4Life]

Well the B21 finally started giving me problems, such as oil burning, oil leaking from the backside of the head gasket, etc. My intentions were to rebuild the B21 back to stock, using honda parts and leave it be. The cylinders look great in the B21, but its getting replaced. So, I am swapping a B20A5 in instead. Here are the plans and checklist......Pics soon to come.

However I understand most of you guys may not have a lot of knowledge about this particular Prelude but I wanted to share my work and progress.

-B20A5 block bored to 83mm--going to machine shop--This will bump compression from 9:1 to a little over 10:1 using OEM parts.
-Honda pistons/rings for a B21--purchased
-Honda main/rod bearings--
-Honda or ARP head studs/bolts and Rod bolts--
-Honda water/oil pump--purchased
-Honda gaskets/timing belt--purchased
-PK2 head-port/polish--working on currently-doing myself-nothing too crazy
-Valve guides/valve seats--machine shop
-JG Engine Dynamics stainless steel valvetrain--purchased
-Web Cams grind#115--maybe...
-Ported/Polished B21 IM w/ 65mm TB--complete
-DC Sports header/Thermal R&D--own
-New clutch for d2j5--have not decided brand
-Fidanza Flywheel--for d2j5
-D2A4 Tranny(90-91)--current trans
-Chipped OBD1 ECU
-Have a decent Tune

I will post updates as I go(along with pics).

UPDATE 10/28/08

So its been a hectic time trying to get everything together and finding time to work on the lude. Its been quiet a while since Ive posted any info. But on a good note I FINALLY, FINALLY,......FINALLY received my valvetrain that I ordered back in June!!! Ive recently progressed a little on the cylinder heads port and polish. Within the next few weeks you guys will be seeing a lot more parts rolling in and some more progression on this car. Heres some pics of the valves, etc, and the work that Ive done on the head so far:
http://i13.photobucket.com/albums/a300/prelude85/DSC00419.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00418.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00420.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00436.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00453.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00457.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00443.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00440.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00437.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00442.jpg
Exhaust-Just started
http://i13.photobucket.com/albums/a300/prelude85/DSC00446.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00447.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00450.jpg



Update:6/27/08
Here is the bottom end, which is in really good condition! Still have to remove the rods and pistons....
http://i13.photobucket.com/albums/a300/prelude85/DSC00261.jpghttp://i13.photobucket.com/albums/a300/prelude85/DSC00259.jpghttp://i13.photobucket.com/albums/a300/prelude85/DSC00258.jpg


Heres the cylinder head. Ive started cleaning up the ports and port matching the intake side. Ive got a lot of work to do here. All of the cast lines and rough-ness will be removed from IN/EX ports. Then all the ports will be polished. After the new valvetrain comes in itll be off to the machine shop to have the guides and valve seats worked.
http://i13.photobucket.com/albums/a300/prelude85/DSC00263.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00255.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00251.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00252.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00257.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00236.jpg

Here is the ported/polished intake mani and 65mm TB which was custom. I completed this project last year.
http://i13.photobucket.com/albums/a300/prelude85/DSC00237.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00239.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC01097.jpg

UPDATE: 6/30/08
I had a small amount of time today, so I decided to start polishing and trying to finish one of the intake ports. I also started on the exhaust side of the head. This has been really time consuming....I really need to take a vacation so that I can get this head done!!! Keep in mind this is my FIRST time porting/polishing a cylinder head. Ive done a few intake manifolds and other machine work, but not a head. Its fun and a learning experience for me, but I think itll perform a little better than stock. So here are some pictures:
http://i13.photobucket.com/albums/a300/prelude85/DSC00273.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00275.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00276.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00277.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00278.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00279.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00283.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00287.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00274.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00290.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00291.jpg?SSImageQuality=Full

Started one of the exhaust ports.....
http://i13.photobucket.com/albums/a300/prelude85/DSC00289.jpg
http://i13.photobucket.com/albums/a300/prelude85/DSC00288.jpg

[9ussy]

nice porting job..

[j0nbunklah0m]

nice nice wat do u use to port n polish?

[Dirty Octopus™]

you are somethin' else my friend :goodjob:

i love your love for this car.

[southside]

Dang Nice port and polish.I wanna know what you use too

[BA4Life]

All that I have used to do the port work consists of: a dremel tool, flex-shaft, drum sanding bands (60 and 120 grit), flap wheel (120 grit), a few grinding stones, and some abrasive buffing heads (120, 280, 320 grit). Havent even used the fine grit buffing heads yet. Ill use those after the head has been reworked at the machine shop(valve guides, seats), and hot tanked. Thanks for the feedback guys.

[southside]

All that I have used to do the port work consists of: a dremel tool, flex-shaft, drum sanding bands (60 and 120 grit), flap wheel (120 grit), a few grinding stones, and some abrasive buffing heads (120, 280, 320 grit). Havent even used the fine grit buffing heads yet. Ill use those after the head has been reworked at the machine shop(valve guides, seats), and hot tanked. Thanks for the feedback guys.Where can I find these?

[BA4Life]

Lowes, Wal-mart, Home Depot....They are in seperate packs with the dremel accessories. I spent about $50 for all the accessories that I wanted....Must have the heads and attachments that I listed...it makes things easier.

[Sol-Badguy]

Now you know why I got rid of mine. My B21 was drinking oil and coolant everyday. I really can't wait to see how this thing turns out with the A5 in it!

I actually figured you'd go with a B20A over the US motor.

[BA4Life]

Now you know why I got rid of mine. My B21 was drinking oil and coolant everyday. I really can't wait to see how this thing turns out with the A5 in it!

I actually figured you'd go with a B20A over the US motor.

My b21 was pouring oil out of the head gasket and the valve stem seals were SHOT!! Other than that its in GREAT condition. I decided to go with the b20a5 block and head, so that I could gain some compression with OEM parts. After being bored from 81mm to 83mm and keeping the small combustion chamber head (PK2) itll gain just over 10:1 comp. from that lame 9:1. There is no difference in the b20a and the b20a5....they make like 5hp more than the U.S. spec. Which is not worth it considering that Im doing a rebuild. I think Itll run pretty well when its all said and done. There will be some cams being added to this build later. I just havent decided on which profiles to get.

[Sol-Badguy]

Are you sure you want to bore out the block that much? I thought when Honda took it to 82mm for the B21, the walls were too thin and that's why they went FRM?

[BA4Life]

Are you sure you want to bore out the block that much? I thought when Honda took it to 82mm for the B21, the walls were too thin and that's why they went FRM?

Yea, its been done tons of times with no issues. You have to think of it this way....its only taking a milimeter out all the way around the cylinder. Theres plenty of room. The B21 is a 83mm stock. Thats why Im using the new Honda b21 pistons.

[FasTech]

Why didn't you just go ahead and build a JDM B20a? I had an extra block!

[FasTech]

Sell me your DC Sports Header! I can't find one anywhere.

[BA4Life]

Sell me your DC Sports Header! I can't find one
anywhere.

haha, nah Ill pass! Yea I bought mine about 6yrs ago from the forest park nopi warehouse. I had a spare b20a5 block, so Im building it.....and besides how would I have known you had a spare b20a?? lol

[jtaylor48]

I did the same swap. I had a b21 in my lude and swapped the b20a5. My b21 had bad rod and mains and the knock didn't get much better after replacing so I just said **** it. I'll just swap it. Still ran almost as strong.

[FasTech]

haha, nah Ill pass! Yea I bought mine about 6yrs ago from the forest park nopi warehouse. I had a spare b20a5 block, so Im building it.....and besides how would I have known you had a spare b20a?? lol


I thought I told you awhile back when you sent me that type-r throttle body info.. But if you ever come across another DC Sports Header please let me know! I found one on prelude-power.com but some a$$ hole had already bought it...lol

[BA4Life]

you may have told me haha, but I dont remember.....B20A5 and B20A are the same. Theres no point in getting a Jdm B20a when Im doing a rebuild. I already had the B20A5.

[BA4Life]

Well didnt get much accomplished today....Im working on getting the head finished and waiting on the new valvetrain so that I can drop it by the machine shop for reworked valve seats and guides. Im just going back with the stock 3 angle valve job. I should see a big difference in that alone. The vavle job will net the most power next to the bump in compression.

[Sol-Badguy]

I CAN'T WAIT TO SEE THIS!!!!

I had a Pacesetter header on my B21. It actually felt niice.

[BA4Life]

I CAN'T WAIT TO SEE THIS!!!!

I had a Pacesetter header on my B21. It actually felt niice.

I cant wait till Im done! Im going crazy:crazy:....I have NO time to work on it! But uhh....I decided to put some cams in this build. Im more than likely goin to order Web Cams grind #115. They have a .418/.418 lift, 242/242 duration. Duration @.050" 220/220 degrees.

[TheChosenOne]

I cant wait till Im done! Im going crazy:crazy:....I have NO time to work on it! But uhh....I decided to put some cams in this build. Im more than likely goin to order Web Cams grind #115. They have a .418/.418 lift, 242/242 duration. Duration @.050" 220/220 degrees. I'm not completely firmiliar with this motor specifically, but get a bigger regrind. I know f22a1, a4, & a6's can run a Delta 272 regrind with stock valvetrain and rev 1.5k over redline with no problem. The Idle is a little rough, but do-able, none-the-less.

So, even if you want something a little more smooth, the 242 could afford to bumped up a good bit! :goodjob:

Just my :2cents: ... Love the Lude.

[BA4Life]

I'm not completely firmiliar with this motor specifically, but get a bigger regrind. I know f22a1, a4, & a6's can run a Delta 272 regrind with stock valvetrain and rev 1.5k over redline with no problem. The Idle is a little rough, but do-able, none-the-less.

So, even if you want something a little more smooth, the 242 could afford to bumped up a good bit! :goodjob:

Just my :2cents: ... Love the Lude.

Yea Id like to go bigger, but I know that these cams make a BIG difference in these motors. Not to mention that its the biggest that is listed as of right now without having to get a custom grind. But basically the stock cams SUCK!!! Theres a guy on preludepower.com that specd the stock cams at all degress and the specs are ridiculous. I dont even know how they made 140hp stock, theyre that bad. If youre interested I can give you the link to the write-up. But anyway, theres a lude coming out--as in will be in a magazine pretty soon that is using these cams, and is "supposed" to be making some gnarly numbers for these "b"(b20/b21) series. But we shall see.

[TheChosenOne]

Well consider me subscribed 2 this thread. Once I get outta debt, ima get me some cams

[89preludesi]

I cant wait then you can help me with mine hahahaha :yes:

[JDM SLiViC]

So Stephon finally decided to show us whats up with the lude lol
cant wait till he brings it back out!

[BA4Life]

^^haha those pics of the head.....It looks waaay better now! My valvetrain SUPPOSEDLY shipped out today!!! FINALLY BISHES!!!

[TheChosenOne]

^^haha those pics of the head.....It looks waaay better now! My valvetrain SUPPOSEDLY shipped out today!!! FINALLY BISHES!!!
I've been waitin' homey! I got my cam in about a month ago but i'm still waiting to get tuned. :(

Post some pics of the progress!!!:boobies:

[BA4Life]

UPDATE top of page 1!

[TheChosenOne]

SOoOoOo, when you gunna assemble? I NeEeEed more pixxx!!!:boobies::taun::crazy::D:bump:

[rhd_civic_ej]

stephen...you are gay


but just kidding should be stellar when its all finished up my friend hit me up sometime foo, i only like like 2 min from your work now

[dabuilding]

man ill always love these preludes my first car was an 86 carbed

[SPOOLIN]

what the hell is the hold up?

[southside]

what the hell is the hold up?x2

[h22lude]

where does a b20a5 come from?

[southside]

still doing this or no?

[SPOOLIN]

hell naw he saw the light he'll do an h22a swap :)

[sikfricks]

any progress