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So i picked up an 89 2.0 si 2ws on Craigslist and the engine blew a rod the next day so i have to swap engines now. I know I can drop a b20b in but will I have to change my trans too? All help is appreciated
 

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Sean (1funryd) and Dave (Mustardcat) are the guys to talk to about the B20b/z swap. It's not simple or cheap, and does in fact require changing a lot of things to make it work, so yes....you'll have to get a B20B long block, a transmission, motor mounts, half-shaft axles, hubs, no doubt some other things too, which Sean and Dave can tell you all about - follow their thread on the B20b/z swap for all the details.

It's a pity the B20/21A series are so unimpressive for power and reliability beyond factory parameters...it's one of the main reasons 3g ludes have such piss poor aftermarket support. Virtually nothing about the 3g lude is compatible with other B series engines, at least in part because the B20/21A engines in the lude are laid over like 18 degrees to give a low hood profile and all other Honda engines sit straight up and down in their respective chassis, which is in turn another reason why motor mounts have to change to swap in other powerplants. The stock engines don't have VTEC or a rev limiter - people frequently blow them up by revving them too high because they think all Honda motors are fine with 6500+ revs, which is not the case with these old ones. They're not like the B16/18/20 VTEC engines, or the H series or K series and are poorly balanced in comparison (you can happily get 10k revs out of a properly built K-series, but a B20/21A will shred itself before it gets anywhere near that). Redline is actually about 6200-ish in these old bastard Bs. Much above that, mechanical failure is imminent and inevitable.
The B20b/z swap is worth it if you don't mind spending the cash and doing the custom work, although 1funryd and Mustardcat are still working out some kinks. The H-series swap is tried and true. Plenty of people have done that and there is loads of information on it here on this forum. K-series swap has little official development at this time, so less information available on it....but there are a couple people here who have done it, somehow. I imagine it's just as involved as any B H or F series swap, maybe more so. Use the search function to find some more information on it. In the meantime, here's a link to Sean's experimental build with the B20B, which is a great read/watch (there's videos). Enjoy!

 

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Sean (1funryd) and Dave (Mustardcat) are the guys to talk to about the B20b/z swap. It's not simple or cheap, and does in fact require changing a lot of things to make it work, so yes....you'll have to get a B20B long block, a transmission, motor mounts, half-shaft axles, hubs, no doubt some other things too, which Sean and Dave can tell you all about - follow their thread on the B20b/z swap for all the details.

It's a pity the B20/21A series are so unimpressive for power and reliability beyond factory parameters...it's one of the main reasons 3g ludes have such piss poor aftermarket support. Virtually nothing about the 3g lude is compatible with other B series engines. The stock engines don't have VTEC or a rev limiter - people frequently blow them up by revving them too high because they think all Honda motors are fine with 6500+ revs, which is not the case with these old ones. They're not like the B16/18/20 VTEC engines, or the H series or K series and are poorly balanced in comparison (you can happily get 10k revs out of a properly built K-series, but you'll never get anything close to that out of a B20/21A series without destroying it). Redline is actually about 6200-ish in these old bastard Bs. Much above that, mechanical failure is imminent and inevitable.
The B20b/z swap is worth it if you don't mind spending the cash and doing the custom work, although 1funryd and Mustardcat are still working out some kinks. The H-series swap is tried and true. Plenty of people have done that and there is loads of information on it here on this forum. K-series swap has little official development at this time, so less information available on it....but there are a couple people here who have done it, somehow. I imagine it's just as involved as any B H or F series swap, maybe more so. Use the search function to find some more information on it. In the meantime, here's a link to Sean's experimental build with the B20B, which is a great read/watch (there's videos). Enjoy!

Thanks alot man! And yeh the guy i got it off was gonna put a H22 in and he gave me the motor mounts and CV joints and a whole shit ton of parts. Also how hard would the conversion from automatic to manual be do you think
 

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LOL I'm sure that's not too bad if you're already changing out parts for a motor swap. All of that would likely have to go anyway. Since you already have the motor mounts and CV joints, why not just go with the H22 swap? Those are actually consistently cheaper than a B20b, at least on Ebay....however, I'd never buy one without rebuilding the whole thing first, because you know any previous owner of one of those just beat the living piss out of it, vs. a B20b is prolly pretty safe since they came without VTEC in passenger vehicles like CRVs and Elements. However, the motor mounts between the two are not interchangeable. If you want to change the engine to anything but a B20/21A series, all of that hardware has to be changed, specific to the powertrain you plan to put in it. If you were changing auto to manual with the B20/21A still under the hood, about the only things needing changed besides the transmission itself would be the CV axles and maybe the hubs (I understand the spline count is different between the two), and installing the related manual transmission accoutrements like clutch master and slave cylinders, related hoses and linkages, add the 3rd pedal inside and shifter and related hardware (but don't quote me on that, since I've never had to do that swap...yet. Every lude I've ever owned apart from the '89 chassis in my profile pic has been a manual.) Other powertrains....ALL of that would have to be changed under all circumstances. Very possible, but also very involved and very expensive, and you better not mind getting dirty and some hard work. Sounds like you got nothing left to lose, brother. DO IT!!!! :D
 

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Here's this one too:


Sean isn't the only one to make a thread regarding this particular swap. There are tons of others. Some have information others don't and vice versa.
 

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Discussion Starter #6
Here's this one too:


Sean isn't the only one to make a thread regarding this particular swap. There are tons of others. Some have information others don't and vice versa.
Yeh I read shawns thread I'm prolly just goin to put an h22 in like him. I just wanna get it started back up and running mostly everything else on the car has been done and it was running great and smooth before the engine blew :cry:
 

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Yeah, like I said, that's too bad. I feel for you. One of the chassis I have has a B21A1 with a hole in the block thanks to the idiot kid who had it before me....revved it too high trying to look cool to his friends, no doubt. I have a couple extra engines sitting around that I'm working on right now. Not right now right now (it's winter, the cars are outside, there's 3 ft of snow on them and the ground AND it's like -20f outside to boot), but in the works, you know? The only reason I'm not doing a swap like others is because I happen to already have those bastard Bs from previous project 'ludes that aren't around anymore, and I figure, "Why let them go to waste?" I'll do something with them rather than toss them out. I know I'll never make power out of them, but the car was plenty fun to drive even with only about a buck20 horsepower, and I know I can address the reliability issues with a rebuild. The thread I started to document this rebuild and restore (which can also be found on this forum) is likely not to go anywhere until it thaws - it's just too cold to be outside working on a car. Negative 20 is no freekin' joke.
On a good note, if everything else is done, hopefully you won't have to worry about replacing suspension components like ball joints and such right away. Although if you don't have 4ws, I would check the condition of the rear toe arms IMMEDIATELY especially if your chassis has over 150k on it. Those go bad, will make your car handle like ASS, especially in winter conditions and you can no longer source the replacement parts from Honda. The only option are aftermarket adjustable rear toe arms made for 4-5g 'ludes - they can be made to fit 3gs, but officially they're not listed as parts that fit. These are awesome chassis, the 3gs....but holding onto them is not for the faint-hearted. Your love for this car will be put to the test, trust me. o_O It will drive you crazy for at least a little while....but, an engine swap like that is totally worth it: A) it opens you up to a powerplant that actually has decent aftermarket support, and B) this chassis can do nothing but benefit from having a more modern powerplant under the hood, and it will be quick and reliable and make you fall in love with it all over again. You'll never want to get rid of it afterwards. Just watch out for car thieves and vandals - they tend to get jealous and covetous of these and how cool they are and will try to wreck your ride or take it from you (just look at Sean's more recent threads on the forum - someone tried to do that with his not even that long ago). Buy a CLUB. Ultimately, it won't stop anyone stealing a car who is determined to make off with it, but it will make them take the extra step of having to cut it or the steering wheel off with a power tool, which is something surprisingly few car thieves are prepared to do. Vandals, those are another story.
 

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Well if you have all the stuff to do the H22 swap then go that route. Like Marcus stated I offer all the support parts for swapping our ludes due to the fact that there is literally nothing left to support the bastard b.

And why waste money on that motor when its lack luster power range is just not satisfying.
This car is fun with more power and especially NA power.
Turbo is fun but it breaks down much quicker than NA setups depending on how far you take each build.
 

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Yeah, man. If I didn't already have these others sitting around, I'd totally do one of those swaps. I love the idea of having an H or proper B series under the hood....I'm just not prepared to spend the kind of cash I would need to at this time.

Used H22A - Ebay price = approx. $600 for one listed as "parts engine for rebuild only." Does not come with ECU, wiring or transmission. Want one that doesn't need an immediate rebuild or perhaps comes with a transmission? Double, triple, quadruple that.
Rebuild kit for H22A = approx. $300-ish, half that if you can do without replacing pistons and rods.
Manual transmission for H22 = anywhere from $500 to $1000, depending on mileage and who the supplier is
1funryd motor mount conversion kit = approx. $505 (price + shipping)
Axles = approx. $200
Wiring harness = (according to the admittedly old H22 parts checklist) approx. $480?
I already have a P75 ECU sitting around which should work for a conversion like this - if not for an H22/23, it should work for a regular B series and can be tuned, so I don't think I'd have to buy one. Not perfectly sure on that, though.

there is no doubt in my mind that I'm missing some critical components from this list....but we're at $2585 at the low side so far, or $3085 at my high end. Lotta cash. Worth it, but its a lot.

A B20B on ebay in comparison is around the $7-800 mark without the VTEC head. $1600-ish with a transmission one of us could make use of.
K-series is similarly priced, comes with iVTEC...but we have no comprehensive parts list and conversion documentation for it, so cost to do that is kind of up in the air. That, and most of us kind of balk at the possibility of having to cut a hole in the hood to make it fit. I've seen some super ugly examples, so I don't blame anyone for feeling that way.
 

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I believe an H series swap presents with ground clearance issues.... Also, doesn’t the H Series also have FRM in the cylinders (like the B21A1).... Some say FRM was “perfected in H Series).
I like Sean’s B20B swap, but do ya need the B20B/Z in order to gain vs lose HP vs the B20A5 or B21A1?
 

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I've never heard anything about clearance issues with the H22, probably because the development of the swap kits has taken that into account over the years and solved the problem if it existed to start with - It's been noted that the F-series and K-series definitely have clearance issues...but also that those issues can probably be solved given enough time and experimentation; and yes, the H-series have FRM cylinder sleeves. There is also no doubt Honda's manufacture of those cylinder sleeves was lots better with the H-series and only got better from there. I could be wrong about this, but it is my understanding that Honda is no longer manufacturing engines of any line with iron sleeves, making use of that testbed research they did with the FRM. It's possible that they use FRM in all their engines now.
I'm not sure what you're asking with the last question...Of course you'll gain horsepower with an engine swap, no matter what it is. You could hardly end up with less. LOL The B20/21A series is pathetically underpowered, and there really isn't a whole lot one can do to them for any appreciable gains aside from adding forced induction. You can dump a metric tonne of money into an NA build on a B20/21A and still be under 200hp, if that answers your question. H22 will meet or come very close to 200 right outta the box. B20B/Z prolly a little less, as it is not a VTEC engine from the factory....but adding a VTEC head and proper tuning will probably put it in similar territory to the H22, maybe better. All the aftermarket support that the B20/21A lacks is present for either of those swaps, which means there's a hell of a lot more you can do for power. Like I said above....if I didn't already have extra bastard Bs sitting around, I'd be tackling a swap like this for sure.
 

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I've never heard anything about clearance issues with the H22, probably because the development of the swap kits has taken that into account over the years and solved the problem if it existed to start with - It's been noted that the F-series and K-series definitely have clearance issues...but also that those issues can probably be solved given enough time and experimentation; and yes, the H-series have FRM cylinder sleeves. There is also no doubt Honda's manufacture of those cylinder sleeves was lots better with the H-series and only got better from there. I could be wrong about this, but it is my understanding that Honda is no longer manufacturing engines of any line with iron sleeves, making use of that testbed research they did with the FRM. It's possible that they use FRM in all their engines now.
I'm not sure what you're asking with the last question...Of course you'll gain horsepower with an engine swap, no matter what it is. You could hardly end up with less. LOL The B20/21A series is pathetically underpowered, and there really isn't a whole lot one can do to them for any appreciable gains aside from adding forced induction. You can dump a metric tonne of money into an NA build on a B20/21A and still be under 200hp, if that answers your question. H22 will meet or come very close to 200 right outta the box. B20B/Z prolly a little less, as it is not a VTEC engine from the factory....but adding a VTEC head and proper tuning will probably put it in similar territory to the H22, maybe better. All the aftermarket support that the B20/21A lacks is present for either of those swaps, which means there's a hell of a lot more you can do for power. Like I said above....if I didn't already have extra bastard Bs sitting around, I'd be tackling a swap like this for sure.
Input Much appreciated ... I’m probably wrong, but I thought 1funryd cited lower ground clearance on the H Swaps vs factory whereas B20B swap had ground clearance closer to factory??

I wish 1funryd would be willing to swap an engine for me... I have 1 owner (me) 3G Lude ‘91 model with B21A1 with Mint Body/Paint... Garaged x 30 yrs... It has 18O PSI across all 4 cylinders... IT JUST USES OIL. Maybe just Valve Stem Seals, but a rebuilt B20B would be Schweet!
 

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I believe an H series swap presents with ground clearance issues.... Also, doesn’t the H Series also have FRM in the cylinders (like the B21A1).... Some say FRM was “perfected in H Series).
I like Sean’s B20B swap, but do ya need the B20B/Z in order to gain vs lose HP vs the B20A5 or B21A1?
The H/F series swap is definitely lower than the bastard b. But if you get proper Ksport coilovers from me, and purchase my traction bar with skid bar that will help protect your investment into the H/F series swap.

As for the B-Series swap, you gain about an 1-1.5" back so its better for sure.
But the real benefit is that you no longer have to wait weeks for a part and will be able to use so much of the aftermarket that has been established for the H-B series swaps.
Which the bastard b never had and still does not.

...I wish 1funryd would be willing to swap an engine for me... I have 1 owner (me) 3G Lude ‘91 model with B21A1 with Mint Body/Paint... Garaged x 30 yrs... It has 18O PSI across all 4 cylinders... IT JUST USES OIL. Maybe just Valve Stem Seals, but a rebuilt B20B would be Schweet!
If your willing to pay for the transport of your lude and my swap fee and all the accompanying parts, I can get it done and driving and then ship it back...;)
 

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Input Much appreciated ... I’m probably wrong, but I thought 1funryd cited lower ground clearance on the H Swaps vs factory whereas B20B swap had ground clearance closer to factory??

I wish 1funryd would be willing to swap an engine for me... I have 1 owner (me) 3G Lude ‘91 model with B21A1 with Mint Body/Paint... Garaged x 30 yrs... It has 18O PSI across all 4 cylinders... IT JUST USES OIL. Maybe just Valve Stem Seals, but a rebuilt B20B would be Schweet!
He did cite that, but I thought the H series mounts that were being produced now addressed that issue. Hasport and AZ R&M had not previously, neither of which produces the parts anymore; both had some minor issues with fitment and clearance, but I thought Sean and Dave's rehash actually fixed it up...Sean's involved in this thread, so it's easy to just ask how that worked out, I suppose. LOL I'm still super interested to see the final product of the B20B swap. Those are much more available - I could find one of those locally for sure, for maybe like $100, long as I pull it myself. That would be amazing. If I could find a wrecked CRV with a B20B, ideally with a FWD manual transmission and pull it for even a couple hundred, that would make my mind up. LOL
No matter what, one of the 2 chassis I just bought will have a bastard B in it. My son is getting one of these cars. He's 15 and doesn't know the first thing about working on a car or troubleshooting it, etc....so that will be part of his education....but meanwhile, I want him to be able to use the shop manual to address problems, or at least be able to take it to a mechanic himself and expect them to know what they're doing.

If you're the only owner of that lude for 30+ years and haven't abused it, it probably is the valve stem seals or guides. Also, if it's got a decent amount of miles on it, you might consider a full gasket set. I found that mine was using oil, but it was leaking way more than it burned - the timing side of the engine was a caked on-baked on mess under the plastic cover. The cam seals were just pouring oil out, and so was the front main, the pan and the valve cover. Head was also seeping a tiny bit. With the B21 apart, I've seen that the gaskets and seals are the main cause of the missing oil, all the valve stems seals, as well as a burnt valve in cylinder #1 (see my rebuild and restore thread for pics). That engine had 262k on it when it was pulled from the lude it came out of, and I don't see any issues in the bottom end at all. Check that stuff for sure!
 

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If your willing to pay for the transport of your lude and my swap fee and all the accompanying parts, I can get it done and driving and then ship it back...;)
[/QUOTE]

Thanks Sean... I am tempted to put the Lude in a Box Truck and send it to you in WA State!

One thing I am confused about with B20b/z swap is the transmission. What transmission do we need for B20b/z and from what vehicle? I know you said we need an "S80" Transmission, but does it have to be the manual transmission from the CR-V? I am reading other posts that cite we shoud use a "GSR" transmission.

Also, WHERE do you source engines? ... and do you rebuild the B20b/z internals or have trust in a sourced engine as is?

What is your opinion of some Crate Engine providers? ATK Engines??

The B20b swap makes soo much sense for those babying a still running B21A1... Replacement parts for the B21A1 are just not there...

If and when you take on a job of this magnitude, what sort of time-frame is involved... Like the rest of us, you have a daytime job.
 

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If your willing to pay for the transport of your lude and my swap fee and all the accompanying parts, I can get it done and driving and then ship it back...;)
Thanks Sean... I am tempted to put the Lude in a Box Truck and send it to you in WA State!

One thing I am confused about with B20b/z swap is the transmission. What transmission do we need for B20b/z and from what vehicle? I know you said we need an "S80" Transmission, but does it have to be the manual transmission from the CR-V? I am reading other posts that cite we shoud use a "GSR" transmission.

Also, WHERE do you source engines? ... and do you rebuild the B20b/z internals or have trust in a sourced engine as is?

What is your opinion of some Crate Engine providers? ATK Engines??

The B20b swap makes soo much sense for those babying a still running B21A1... Replacement parts for the B21A1 are just not there...

If and when you take on a job of this magnitude, what sort of time-frame is involved... Like the rest of us, you have a daytime job.
[/QUOTE]

... AND ONE MORE THING... IF YOUR LUCKY ENOUGH TO SOURCE THE B20Z WITH HIGHER HP (NON VTEC), WHERE DO YOU GET A "LOW PROFILE INTAKE" IN ORDER TO CLEAR HOOD?
 

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If your willing to pay for the transport of your lude and my swap fee and all the accompanying parts, I can get it done and driving and then ship it back...;)


Thanks Sean... I am tempted to put the Lude in a Box Truck and send it to you in WA State!

One thing I am confused about with B20b/z swap is the transmission. What transmission do we need for B20b/z and from what vehicle? I know you said we need an "S80" Transmission, but does it have to be the manual transmission from the CR-V? I am reading other posts that cite we shoud use a "GSR" transmission.

Also, WHERE do you source engines? ... and do you rebuild the B20b/z internals or have trust in a sourced engine as is?

What is your opinion of some Crate Engine providers? ATK Engines??

The B20b swap makes soo much sense for those babying a still running B21A1... Replacement parts for the B21A1 are just not there...

If and when you take on a job of this magnitude, what sort of time-frame is involved... Like the rest of us, you have a daytime job.
I personally sourced my engine online from www.jdmenginedepot.com in New Jersey.
But these days many of the jdm dealers are moving their inventory too K series and J series motors.
You can still find the B20b/z motors locally or ebay or other online jdm engine dealers.
Here are some links:
1. HONDA CR-V (1999-2001) DOHC HIGH COMPRESSION JDM ENGINE - B20B - REPLACES B20Z2
2. HONDA CR-V (1997-2001) HIGH COMPRESSION JDM ENGINE - B20B - REPLACES B20Z2


I was fortunate because mine came with the low profile intake manifold, but the beauty of the B series is that you can use a B18 from a 94-01 Acura integra LS model.
 

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Do you rebuild them fresh before you use them, Sean? I mean, I would, since it's conveniently out of the chassis already, but maybe it's not necessary?
 

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Do you rebuild them fresh before you use them, Sean? I mean, I would, since it's conveniently out of the chassis already, but maybe it's not necessary?
My B20b was just dropped in, other than changing the timing belt, and water pump and normal seals.
If you want to open up the motor and let all the Honda butterflies out on a low mileage motor thats up to you.
Even the low mileage motors can have some issues as well.
But mine is pretty much all stock, except now it has a rebuild B18 GSR head so that part is 0 miles when we put it on.
 
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