Honda Prelude Forum - PreludeDriver.com

First off awesome site! I have searched other prelude sites and was to afraid to ask anything cause they will just flame you and tell you to use the search option. Anyways here's my story:

I recently purchased 2 ludes but i am completely new to this. I bought a white (manual) 1988 SI 4WS that is pretty rusted with sagging front and rear bumpers along with dings and dents. Drives Ok but could be better. Has the B20A5 engine which was supposedly rebuilt. I did a compression test at Honda and got 170 - 160. It has 287,600kms. I paid 600 for it.

Then i bought a black 1990 SR Automatic with very, very minimal rust great panel alignment throughout the car, new windshield starts up fine with only 134,000kms. But previous owner ran over something that tore a hole in the radiator and messed up the front wheel alignment (i think).
I paid 400 for it.

Originally i bought the 90 SR as a parts car for my 88 4ws. I was gonna interchange the doors, quarter panels, hood, windshield and whatever else i can get away with. However the 90SR is so much nicer and in much much better shape then the 88, unfortunately it's and automatic.

So now Im thinking of converting the 90sr to a manual transmission taking the parts from the 88 along with swapping the B20 head onto the B21 block. Also taking the 4ws out of the 88 and slapping it on the 90. I guess the only good thing about the rusted 88 is it has the 4ws and rebuilt b20, but its rusted as hell and i don't want to risk taking all the panels off the 90 only to find out the 88's frame is garbage. I didn't take the cars to a body shop yet to determine the corrosion But just from looking at it it looks bad.

I was hoping that someone here is from Calgary (or close to me) that I can bum some knowledge from or that can help me with this project/conversion/swap. I want to do it as a DIY or with a partner of course to save money. I am a total noob when it comes with taking, removing, swapping or doing anything under the hood. However this is a growing passion so the only way to learn is to dive in. I plan to have this set up until next year, then i plan to swap for the h22. If anyone can help me ill be happy to pay for your help or get you some discounts at Honda... I work in their parts dept.

Any helpful feedback, opinions or whatever would be great from anyone.

Hi Silasluder,

Welcome to PreludeDriver.com. We're glad you're here.

First off, let me say that I think you made the right decision to make the white car the donor and the black car the recipient. It's always easier to mess with mechanical things than it is to fix rust, etc.

As I see it, you've got 4 major tasks ahead of you. We'll try to work out the best order to do them in.

The tasks are:
1 - Fix front end (including radiator) of black lude.
2 - Move 4ws from white to black.
3 - Move manual tranny from white to black
4 - Move engine from white to black (optional).

I should note at this point that number 4 is actually an optional step. You mentioned that the black car had low mileage, so I wonder if you may just want to keep the engine that it has in it. Plus, it's an SR, so that's a 2.1 litre rather than the 2.0 litre in the white car. The biggest problem here is that the ECU in the black car is for an automatic transmission, so if you decide to keep the B21A1 in the black car you'll need to find a different ECU for it before you can run the manual. Head to your local Pick N' Pull to find said ECU. It may take a few months to locate one for a manual SR, but I'm sure you could find one. Also note that the B21 is an OBD1 engine while the B20A5 is an OBD0 engine, so you can't just take the ECU from the white car. Too bad. All this being said, you could just decide to pull the B21 for later use and drop the B20A5 into the black car and carry on with life. You'll have to swap all the wiring out and the ECU if this is the case. Let us know what you decide for this part and I'm sure we can come up with a solid action plan for making it all happen.

For now though, I'll provide you with my thoughts on the first three steps. None of this is terribly hard, but you will need a good set of tools. Here's what I think you'll want:

-A decent tool set. Doesn't have to be large. I can take apart almost my entire car with my Craftsman tool set that fits into a case about the size of a small suitcase. Just basic ratchets, sockets, and a set of wrenches. You probably already have this.
-2 (or preferably 4) good jack stands. Cheap at Canadian tire, and they are very useful. A must have for any mechanic. This provides you with a safe way to keep the car off the ground when you've got things torn apart.
-A 32mm (or it might be 36mm, I'll have to check) socket to remove the hub nuts. You'll need to do this when you take your axles off for the engine swap. 5 bucks at Sears.
-A breaker bar that fits your sockets. Get a long one. Since you're going to be taking apart some large parts on the underside of the car and the bolts will likely be tighter than you can muster off with a stubby 3/8 ratchet. Not expensive, and a good way to save breaking your hand.
-A good jack, to lift the car.
-An engine hoist. Required if you plan to swap the engine. More expensive than the other tools, but if you're going to be swapping engines, a must have. Useful for the tranny swap as well, although I happen to know from personal experience than two strong guys can work together to haul a tranny out of a car bare handed if need be.
-A torque wrench. A nice to have, but since I believe in torquing things to factory spec, it's a good thing to invest in. Get a decent one with a warranty, and never use it as a breaker bar.
-Rags, rags and more rags. This will get messy.

I'll stop there for now to see where you're at. Let us know about which engine you want to use, and then we'll start going through the tasks bit at a time. I want to set this up so that you can do everything in a good order. You'll be taking the black car very very apart and then rebuilding it. We'll find a good order to do this in so that you don't set yourself back by doing things like re-installing the exhaust only to find out that you need to take it off again to get the 4ws on.

Stay in touch!

Great Advice, deeply appreciated. Like I said i am pretty new to auto mechanics but I'm a quick and dedicated learner. I will be more confident with your step by step help... hope you don't mind

OK so i will go ahead with fixing the RAD and buying some Jacks today to have a real clear look under the chassis. Like I said the guy that sold it to me said there is a minor gash in the bottom somewhere and the alignment might be off. Ill access the damage and let you know what i see.

I didn't realize that the AT to MT conversion also needed the ECU change. Does it have to be a 90 SR ECU? or can it be either 90-91 model? Cause i think 90-91 are all OBD1? (correct me if im wrong)
Is converting the AT to MT a difficult task? Difficult as in I need to be super mechanically inclined? or can it be done by following step by step directions? (stupid question i know) Would you consider it to be more difficult then an engine swap?

I guess until i get the Manual ECU part I will stick with 2 tasks:
1. Fix RAD and damage if any under the car
2. Transfer 4ws over to black car (ill definately need your help with this)

I will stick with the b21 too. Also I heard the B21 are notorious for burning oil, Is there any way i can fix that problem or improve on it? I guess i should try and get the most of out the engine considering it only has 134,000kms. Heck the car even came with the owners manual and service records in near mint condition. Thanks again for the help, hopefully i can be in the position to help others like yourself.

Happy to help. We're glad you're here. Don't be afraid to ask ANY question, no matter how elementary you may feel it is.

Let's just chat about the AT to Manual swap a bit so that you have a better idea of what is involved. Here are the potential areas that are affected:

-Pedals. The AT doesn't have a clutch pedal, so the pedal system has to be swapped out.
-Cruise Control. If equiped, your cruise works slightly different with the Manual than it did with the AT. This can be sorted out later. I'm a little foggy on what all is involved with this part.
-Guage Cluster - The AT cluster is different than the MT cluster. You can keep the AT cluster in, but certain parts of it (gear selector, S3 light, etc) won't work anymore.
-Shifter assembly - You need ot install the MT shifter and cables to replace the AT gear selector.
-Clutch lines and master cylinder - You have to install the clutch master cylinder and the clutch fluid lines. Luckily this will be easier since you have a donor car for all the parts.
-ECU - There are differences between the AT and MT ECUs. The part I'm not positive of is whether this affects the actualy ECU or the unit underneat the ECU called the ICU. An AT car has a seperate ICU that controls the tranny, and I believe that MT cars also have one, but it's different. On the 90-91 preludes, I believe these boxes can be found underneath the ECUs. If I were you, I would start digging for these things and taking stock of what you have. Then we can research more and figure exactly what you'll need from a wrecker. You'll likely need at least one new version of these boxes. We'll do more research as we get closer. The ECU is dependent also on which engine you have. B21 ECUs are WAY different than B20A5 ECUs.
-Mounting brackets - There are differences here too. Nothing hard to figure out though.

My advice to you is to think of this project as one big rebuild. If you try to do everything in sections you'll end up stabbing yourself in the foot by having to do things twice. It would probably be easiest to just gut the donor car for the parts you need, then take the entire front end of the black car apart (rad out, front bumper off, axles out, etc) so that you have space to work and get these things all sorted out. If I were doing it, I would probably even pull the engines just to give myself space to be fiddling with clutch lines and wiring into the firewall etc. Be sure to label things as you go so that you don't forget where allt he bolts belong. It takes years to memorize how these cars go together. I still label things and put them in baggies for later use and take pictures as I go if I'm tackling new ground. Taking the front end of a car apart is not hard. It's just a lot of work and a lot of time disconnecting wires and hoses. Easy-peasy, but time consuming. I think though that if you give yourself the space to work you'll end up saving effort in the end.

This will be an exciting project. I'll try to write as much as I can to you each chance I get. Get us those pictures though. We can help you identify what needs to be swapped out if the bottom end of black truly is toasted from the impact.

Oh, and on your final note: There is nothing wrong with a B21. Everyone says that they burn oil, but it's just because Honda used a compound called FRM to make the cylinder sleeves in the B21. FRM is ridiculously tough stuff, far more so than steel as it is a composite material. It is hard on rings, but you benefit from very strong cylinder walls. Some owners have reported still seeing the factory cross hatching the cylinder walls past 200,000km, which is un heard of with traditional steel. To fix the oil burning problem, all you have to do is swap out the rings. This isn't that hard, nor is it very expensive. I think that Honda's use of FRM was a great decision. When you pop open the engine and see how thin the cylinder walls are, yet they stand up so well, you'll know why Honda went that direction.

Yeah im pretty excited to get started with the project. I hope the weather in cowtown stays nice so i can begin working.
OK with everything that you mentioned parts wise besides the ECU, will i be able to get most if not all the parts for this swap from my donor car? Or will i need to also buy some new parts? Besides using the owners/service manual do you recommend other reference manuals?

I will be posting some pics up of the 2 cars today or tomorrow. I was hoping to get this project finished soon, but by the looks of it it will take a couple of months to get everything i need and done right. Is pick and pull the best wrecker to find the parts? or do you know of any other wreckers?
Also i heard with 4ws that to prevent any future problems i would need to solder some parts inside the 4ws unit?... is this true?

The only thing holding me back with starting this project is that the donor car is the car that im driving. So i will need to either convince my wife to share her car with me haha, or wait until i have a 2 or 4 day weekend and tackle it head on! Either way its gonna happen sooner rather than later. But that can change if i find out the black car needs only a RAD then i will register it and drive it while i take apart the white car.
Your right this project needs to be thought of as a "big" project rather then multiple projects. Also where is the best place to find and purchase the rings for the b21? thanks again pics coming soon.

You should be able to get almost everything that you need from the donor car. That's what makes this such a great project; lots of work, but not much hunting for parts. I use the service manuals on this site (under the manuals section up top) for everything.

Pick N Pull is a good wrecker. I don't know of a better one in the area.

Solder parts in the 4WS system? The person who said that must have been referring to the 4WS system on the 4th generation preludes (1992-1996). The 4WS system that you have is strictly mechanical. Zero electronics in it, so there is nothing to solder. It has a reputation of being very reliable. I have a 4WS system (yet to be installed), and as all things Honda are, I can vouch for it being very well assembled on inspection. The only thing you need to know about your 4WS system is that once you get it installed, you need to TAKE IT TO HONDA to get it properly aligned. The alignment process requires a special tool, and ordinary shops won't be trained on it. When you go to Honda, talk in person to the mechanic who is going to do the work on your car. Ask him an open ended question about the 'special tool' required to do a 4WS alignment. If you get a blank stare, go someplace else. A seasoned Honda mechanic will be able to tell you what the tool is, and how to use it. This shouldn't be a problem. I have had a great experience with all Honda staffers on the rare occasion I actually need them to do something for me. They're well trained, and they do good work.

I think you're going to need to do something about having a car to drive. It is possible to complete this project in a long weekend, but that will only work if everything goes relatively smoothly, which is rarely does. If you really can't get another car, or heaven forbid, take the bus, then try to chip away at the project while keeping the car operational until you get that 4 day weekend. Then, hit it hard, and get the whole lot done. Nothing you're doing is terribly hard, but you will hit snags, so plan time for this, else you put yourself in a bit of a jam. Just give yourself time. Rushing through a car project is a good way to forget something important, make a mistake, or worse yet, hurt yourself.

Always buy rings from Honda. Case closed. Doesn't matter the application, they're the best ones out there.

Since I am far from a 3rd Gen master, I will continue to leave the best man in charge, in charge of this conversation.

Just wanted to welcome you to the site, SilasLuder!

Learn by asking, we'll do our darndest to get the right answer or hurt ourselves trying!

And teach others by contributing whatever you know..... however small or big.... knowledge is key!

~ Josh

Thanks RedRacer I'm happy to be here.

I haven't been able to do anything yet cause i have been sick with the flu. And mother nature decided to give us a nice snow fall and crazy wind gusts that its to freezing cold in the garage to do anything.
I am hoping for better weather this weekend so i can get started on this project. I will definitely get the rings from Honda and anything else i would need from them too.

I would also like to know if there is a way to check the condition of the M.transmission and clutch? I haven't experienced any probs with them but if there is a few things i should look for or things to replace before installing it it would be great to know. Since most of the parts and hardware will come straight from the donor car I'm a little concerned with the condition of some of the bolts,washers etc since they are so old. Should i replace them? I'm assuming that the home depot/Canadian tire would have what i need and the manual will have the info that i need for bolt specifics.
If you can recommend any little things i should change/replace and the best place to get them please do so.

I will probably take the bus for transportation. Taking the bus would suck so bad that it would kick my but into gear with getting the project done fast. I sometimes tend to have my lazy moments, but taking public trans would change that pretty quickly.
That is all for now.

You'll know the condition of your clutch and tranny based on driving around. Putting in a new clutch when you undertake this project may be a good idea, but it's not a mandatory thing to do. Clutch units aren't that expensive (~$100 or so) and since you'll have the tranny and engine seperated it will be a great oportunity to throw on a new clutch.

Your tranny is pretty fine. Just watch for any gears grinding when you shift (indicating bad shift syncros).

Most of your bolts and washers will likely be okay. Replace any that are in really bad condition, but anything in and around the engine bay will probably be okay. I'll tell you tight now that you're going to have trouble getting the bolt that connects your strut fork to the lower control arm off the car. These are infamous for getting seized. If you can spare the $10 each they cost, not a bad thing to replace when you get them off. These I would buy from Honda.

For other fasteners, poach them from a wrecker or get them at Canadian Tire if you have to. Best bet though is to get parts from Honda, but some people don't like paying $5 for a bolt when the same bolt is 1/3 the price somewhere else. When I say to buy parts from Honda, I don't do it to break the bank, I do it because I have had superb experiences with the quality of all things Honda. Our member RedRacer has actually worked in a Honda plant, and he too can vouch for the attention to detail that Honda puts into their cars. Honda OEM parts are GOOD parts.

Another option you have for transportation is to just buy a really cheap beater car. A bus pass is going to cost you almost a hundred bucks a month, and depending on your commute can have an impact on the amount of time you spend transporting yourself to and from work. When I was doing body work on my 2nd gen years ago I couldn't drive it for a couple of months because I was busy welding panels etc. Rather than take public transit, I spent $100 and bought a '76 Chevelle that had seen a lot of road in its life. The Chevelle wasn't much to look at, but it passed inspection, was reliable and (I'm ashamed to say) had a lot of character. We became friends; some days I still think about my days with the Chevelle. Sure, I missed the 'Lude terribly, but that old beater Chevelle had real character and it never let me down. When it had served its purpose of purveying me back and forth between school while the 'Lude was getting a make-over, I recycled it, and re-couped almost %100 of what I paid for it. Money well spent, and memories that will last forever.

Also, if you're like me and enjoy biking as well, don't discount riding your bike to work as another option. Summer is coming soon, and there are few things better than busting a sweat on the way to the office as long as you have access to someplace to change and clean up when you arrive. During the summer I bike 20km to and from work every day. Great way to get around, and often just as fast as a car because you can take routes cars can't.

Silas,

Have't heard from you in a while. How's progress?