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Discussion Starter · #1 · (Edited)
Hey gang! Been lurking on the list for a few months but haven't posted until now. I'm looking for advice/suggestions/whatever since I'm now faced with building an engine. Here's the situation:

A couple days ago I was driving to work, cruising at about 60MPH. I hear a clunk, and the engine looses power. I push in the clutch and the RPMs drop to zero. Uh oh. Pulled over and tried to start it; turned over slow and was making a rasping noise, wouldn't even fire. Yeah, that's bad. Car was towed to the shop, guy says the timing belt broke and since it's an interference engine, Bad Things(TM).

The car is still in decent shape and should last at least another 2 years before it rots away (I live in the road salt capital of the universe). So I'm planning to build an engine for it.

The car right now is an '87 DX, 1.8L dual carb. Totally stock drivetrain AFAIK. What I want is a mild performance upgrade without having to take out a second mortgage. I'm more interested in torque than HP. More HP is of course better but I'm used to driving big engine cars at low RPMs so I don't want to sacrifice torque for high end HP if I don't have to.

I'm not sure how much I want to put into this but I've set a starting point of $1000(US). I don't know what that will get me as I'm just starting the research now. If it's less great, if not enough, then I'll have to reevaluate.

I am mechanically inclined so I would like to do as much of the work as possible, but I've never built an engine before. I have or can get most any tools needed except for the specialized stuff like for crank balancing, flow testing, and specialty automotive machining. I do have access to a general (non automotive) machine shop though.

So after some initial research here's where I'm at now:
I found a complete A20A1 engine (carbed) for really cheap and plan to pick it up this weekend. It's got roughly 170k miles on it so I'm figuring on doing a complete rebuild. Keeping in mind that I'm interested in torque primarily and HP second, what's the best combination of parts?

A20A1 block is a given.

A1 pistons or A3 pistons? Stock (Honda) or aftermarket?

A20 head or A18 head? I like the simplicity (and cost) of a single downdraft carb. So the A20 head + A20 intake? A hood cowel/scoop would be neat too.

What to do for headwork? Port/polish? Larger valves? How about compression ratio? Is this stuff more for high end HP?

A Cam regrind is a given but what specs?

What carbs to use? A friend has a Weber 32/36 (forget the model) I can use to get this thing going. Upgrade to a 38/38 later? Tuning setup?

The exhaust is not stock and has a performance muffler. Don't know any more than that right now. I'll find out when I get the car back from the shop it was towed to.


I know this is a ton of questions so I'm not expecting a dissertation. Just some general direction for how to proceed given where I'm at.

Right now I'm creating a list of parts and machine work needed to get an estimate for total cost. Obviously it's incomplete right now but I'll update this list (here) as I go:


***The big list of engine stuff and prices***

Parts:
A20A1 engine - ebay - $90
pistons (13102-PJ0-308 ) - hondapartsdeals.com - $175
rings - (sealed power E526KC50MM) - Rock Auto - $76
wrist pins - hondapartsdeals.com - $40
rod/main bearings (Toga HP) - importperformanceparts.net - $95
thrust bearings - hondapartsdeals.com - $10
engine gasket kit (Felpro KS2404) - Rock Auto - $149
spark plugs (NGK 2115) - Rock Auto - $26
spark plug wires (Bosch 381-8065) - Rock Auto - $16
distributor rotor - hondapartsdeals.com - $4
distributor cap - hondapartsdeals.com - $16
ignition coil (accel ACC8140) - advanceautopars.com - $50
expansion plugs (sealed power 381-8065) - Rock Auto - $8
head bolts (ARP 218-4703) - importperformanceparts.net - $89
rod bolts (ARP 208-6001) - importperformanceparts.net - $36
oil pump (Toga OPH15-HV) - importperformanceparts.net - $89
water pump (Topline WPH17) - importperformanceparts.net - $32

valve rockers (1462[1/2]-PC6-600) - hondapartsdeals.com - $136
Timing Belt/tensioner (gates TCK160) - Rock Auto - $46

S&S Header - second hand - $220
Weber 38/38 - ebay - $170
Weber adapter plate - Carbs Unlimited - $65

clutch disk (4822Y30 yellow sprung organic) - clutchnet.com - $95
clutch plate (47615R47 red) - clutchnet.com - $178


Machine work:

degrease/inspect block - $58
bore/hone cylinders (1.8L bored to 2.0L) - $198
Final wash block - $48

balance crank - $99
polish crank - $58

lighten flywheel - $48
balance flywheel - $48

Install ARP rod bolts - $84

Install pistons on rods - $48

cam regrind, stage 1 triflow - (Colt Cams) - $165

Pre/post wash + 3 angle valve job + remachined surface - $296
port cleanup - DIY - Free

bead blast intake manifold - $25

*********************************




Any help will be much appreciated.
Thanks!

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A20a1

Well sounds like you know what you want and you've been studying want we've been saying.
Well with a $1000 budget to be honest your going to be limited to a basic rebuild, but if your able to do your own headwork which would be really just a basic cleanup job and reshape the exhaust port, fitting bigger valves is going to be posible but you would have to put 4 new exhaust valves and use the old exhaust valves and convert them into new inlet valves by machining down in size.
As for the block, Custom forged pistons would take up most of your budget, so i would just go for Honda Accord 3G A20A3/4 pistons which have a slightly higher CR ratio and with some block and head skimming will raise the CR ratio a bit higher again, and no lower CR ratio is not good for gas mileage or for any extra performance, low CR ratio was mainly for areas where poor gas is only available so that engine doesn't blow up, it won't effect loosing torque. But what even you do make sure you buy genuine Honda pistons, you can buy patent pins and Rings Hastings are the best for the money as they are cheap but well made also you will need an oversize to whatever bore size you use as it's best to gap the rings by hand to get the best compression, oem patent pistons are poorly made and designed although they are very cheap they also have a really low CR ratio.
If the crank is in good condition and just needs a polish a wouldn't bother having it balanced as they come spot on from factory wasting time and money, but have your Rods balanced with the new pistons and pins and have the flywheel and new clutch plate from your lude cleaned up and re-balanced, don't use the A20A1 flywheel way too heavy and the
Pacesetter Exhaust header and system will help or a header and a custom system with just 2" piping or you can just try it with what ever you got on there at present first.
Inlet manifold, you can clean up this instead as much as you can to get a nicer finish to speed up the air, corners and bends try to make as smooth as possible a bend without creating holes to the outside, ditching the Honda carbs is the best move as you know and saves a whole heap of trouble with vacuum tubing etc. but keep the ignition setup from the original carbed Lude it's matched with module and coil and does a fairly descent job just maybe get a new cap and rotor i'm still using it with uprated leads and plugs and seems goo upto 200bhp!! And you won't have to re-wire the whole car too which will save time and effort!!
The major problem then comes down to choice of carbs 32/26 or 38/38 the 32/36 is progressive meaning that the smaller one opens first then when you floor it the bigger one opens at full throttle gives you better low end torque but to be honest i'd go with the 38/38 as it opens up both at the same time and they are much bigger with a modded head, and cam you'll get more benefit from the bigger carb with minimal loss in torque. As fasr as camshafts go i'd stick with something conservative maybe try the Colt Triflow with say a 270/260 duration inlet and 280 duration exhaust this should give you excellent all round power with a nice idle.
 

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Discussion Starter · #4 · (Edited)
hondasavela said:
just for giggles, why don't you replace the timing belt to see if you have bent valves or not. often this is all required
When I get the car back I will check it out more. I could just fix it but then I'm stuck with a stock 1.8L. What fun is that? :wink3:

Budget:
I just kinda pulled that number out of my... umm... yeah. So it may not be realistic. I can expand that if need be, I just don't want to dump too much money into a car that could be a rustbucket in 2 years

RJ, been reading a lot of your posts. Good stuff! Sounds like I have nothing to worry about as far as losing torque for HP.
Still digesting. Stay tuned.

C|

5/4/2006
Got the car back today. Pulled the valve and upper timing covers. The belt isn't actually broken but the teeth are stripped out at the bottom, so it might as well be broken. I didn't have time to pull the head but I remember hearing a clunk when it happened, so I'm betting the valves are toast.

I'm picking up the new (old) engine Sunday so after then I can dig in and see what will be needed.

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bent valves

Hmm not good depends how fast you got the clutch in travelling at 60mph mind you bet it's not as bad as when my two conrods departed from the crank at 120mph at 7000rpm that made a clunk and a half not to mention quite a few holes!! Miraculously the head wasn't damaged and only a couple of ever so slightly bent valves might even be poor seating rather than bent did a leak test in the chambers and only let a dribble through on 6 out of 12 valves.
Might be worth pulling out your valves and spinning them up on a lathe to see if bent handy to have spares to turn into bigger valves or if your cambelt screws up again or if you screw up by misaligning :0( (done that before)
 

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Discussion Starter · #6 ·
Work begins

Finally got the A20 home and on the stand. I have the manifolds off already. Next I guess is the head. Is there anything I should do before I start? Anyone interested in pics? I guess I could take some to document the progress.

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Pics are always a good thing. Label everything, it makes the putting back together process alot easier.
 

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Discussion Starter · #9 ·
Cylinder specs

Pulled off the head today (A20). The cylinders look pretty good, no scoring and I can still see the original(?) machine marks, so maybe no boring needed? I measured one of the bores at 3.2565", which leads to some confusion. The engine was taken out of a 1988 Accord, and it's an 'A1 so it has a carb. The cylinder specs I have from a Haynes manual list all 1988 engines at 3.1894" - 3.1898". My measurements match the cylinder specs from '86-'87 fuel injected models (3.2562" - 3.2566"). In the end I don't really care what the actual size is but I want to make sure I get the right pistons. Does anyone have any more reliable engine specs?

I put some pictures here:
http://bluegreenlabs.com/Prelude/Engine-build/

These are pretty big so those on dialup beware.

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bore size

well they all vary a little bit as long as it's not massive amounts out. I allways use 82.75mm it's a bit bigger than stock specs by .05mm but gives you a little more room to breathe if the engine runs hot and if the climate is hot. With this size stock size Honda pistons work fine you can safely go to 83mm but i would run maybe 83.05mm but if your going to be running purely as a road car then stick with the Haynes Manual sizes 83mm and 82.7mm.
 

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Discussion Starter · #11 ·
Parts sources

Finally got the head and block into the shop a couple weeks ago. The basic head work is done, just waiting for the valves to be ground.

The block was inspected and the cylinders have some major ridges, so it needs to be bored. So now I need to order the pistons and rings so the shop knows what size to bore to.

My dumb question of the day is, where would be the best place to get pistons from? The dealer? I want the stock A20A3 pistons but a dealer will likely want real money. Any good places online? All the places I've found so far have either NPR or Topline. Are these comparable to stock?

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Pistons

No don't go with 3rd Party makes they are poo, lower CR ratio and the valve relief pockets are in the wrong place. Bets Pistons to use a forged custom ones but you'll be looking at 4X the price of the stock Honda ones although you would get pins and rings included which with Honda Pistons all you get are the pistons!!!
Best ones to get are the 83mm oversize for a A20A3/A4 you might need to rob a Chassis number from a 3G Accord thats FI or a Lude thats FI so that the dealer can get the right parts for you.
stock size is 82.7mm but 83mm isn't a major bore enough to get you back into shape then just get some Rings that are touch bigger than 83mm and gap them by hand to racing tolerances, don't forget if your going to be thrashing the living life out of it or if the engine is going to be running hotter due to climate or extra engine mods run .05mm extra piston clearance if not stick to recommended stock clearance. Trust me on this unless you want to be putting in new pistons after 15k miles.
 

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Discussion Starter · #13 · (Edited)
Hmm. Stopped by the shop today. The guy says he thinks the cylinders will probably need .03" overbore. That would put the bore at 83.46mm. That sounds way too big for 83mm pistons. Does that mean I can't use OEM?

Oh, and the shop guy recommended Federal Mogul pistons. He said he can get them for $32 each. Next step from there would be forged. Sizes for those are +0.5/0.75/1.0mm.

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Pistons

Nope Federal Mogul are crap there made by some cheap oem third party in Mexico i no this as i've been using them for the last 4 years and of yet haven't had a set last more than 20k miles, there the same as top line and all the other crappy makes oh apart from they put some cream coloured coating on them to make them look good!!

Just stick with Honda but get Federal mogul pins as they are lighter and maybe choose another make in rings sealed power or hastings are okay Goetze too, and i can't imagine that your engine must need bigger than 83mm to straighten out the bores?? Honda do another size up i think it's roughly 83.25mm and then 83.5mm as well but you want the smallest you can get away with.
 

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Discussion Starter · #15 ·
Ok. So it sounds like I pretty much have to go to the dealer.

The guy at the shop showed me the block after they cleaned it. The cylinders have a pretty major ridge so I believe him. He even said it's uncommon for Honda blocks to be that far out.

I'll have to check with the local dealer on Monday and see what they can get me.

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Discussion Starter · #16 ·
According to the local dealer Honda only makes a 0.3mm oversize piston, so if it's out more than that then OEM is a no go. Maybe time to find a plan B.

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wear

I'd look for another block maybe sounds like that ones done a zillion miles to me, but i'd still be surprised if it's more than .3mm out you can allways run a little more clearance 0.05mm extra or maybe look into some forged pistons, or you could go for the third part ones but the low CR ratio won't help you emissions or power output and you'd have to have the valve relief pockets modded to suit if you wanted to run a better camshaft later on.
But you could probably get another block a lot cheaper i'd go with that if the block is that worn i'd hate to think what state the head is in??
 

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Discussion Starter · #18 · (Edited)
The head is fine. They already did the valve seats and I'm just waiting for them to finish the valves. Then I can start on the porting.

This is quite a quandry with the bottom end. At this point I see the following options (in rough order of cost):

1) punch out the A20A1 block and go for forged pistons.

2) punch out the A18 block that's in the prelude now and use OEM A20A3 pistons.

3) find a less worn A20 block and use OEM A20A3 pistons

4) use crappy replacement pistons and hope for the best.


I'm actually leaning towards 1 right now because 2 and 3 will take more time and the cost savings is probably not going to be worth the extra time spent, at least to me. And 4 is a non starter. Why would I go through all this trouble for minimal gain?

So, lets talk forged pistons. Does anyone stock them "off the shelf" or will they have to be custom made? What about rings and pins? Seems like I remember reading somewhere that forged pistons would come with rings and pins included. Maybe I misread.

I'm looking at the Paeco catalog right now. Lots of neat stuff in there. I see JE and Diamond also. Anyone else? Any favorites?

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forged pistons

Nope sorry dude lead time from most companies is 4-6 weeks best peopleto speak to are JE pistons also i'd wait untill i canfind out if i broke conrods to whether you need ARP rod bolts or Eagle H Beam rods if your going for forged might as well have some H beam rods from B18B apparantly they fit and all you need is your forged pistons to have a pistons pin fitted to suit the B18 Rod.
 

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Discussion Starter · #20 ·
Feature Creep

I was hoping you wouldn't say something like that! LOL
I'm inclined to agree with you but this will drive the cost up even more. I haven't had the rods checked but they appear ok, and the crank just needs polishing so the rods are likely good. So how much am I looking at for the Eagle rods?
 
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