89 Prelude S engine swap-HELP!!!! - Honda Prelude Forum

Prelude_2367 · 10-28-2002, 11:24 PM

i need some major advice on which engine i should swap into my 89 Prelude S. Note this is a crappy old S model which is carbed, this is why i need to get that peice of crap out of that car. I tuned the rest of the car like custom interior and custom system, suspension, and paint job and kit. Now i need some real good advice on what engine swap would work for my car. I know an H22a is my first choice but i have heard some there will be some major difficulties with that. Since i drive the car daily, except in
the winter, i need something that isnt as tall as the H22 and wont scrape off the bottom of my engine bay like i was told would happen because my car is lowered. I guess the oil pan is too big or something. I also heard that the H22a swap is pretty much a pain in the @$$ to do anyway. So if you guys can help a fellow luder, it would kick. Thanks for help'n out a newbie. Later

HPRpreludeSOHC · 10-29-2002, 02:28 AM

hrmm... a lot of people told me to sell my S and buy and Si. But since I have already put too much money into my car just like yourself... you have a couple options... first is convert your carb system into FI, that's a pain in the ass too... once you have a fuel injection system, you can then opt to get a twin cam motor, H22A, or whatever you prefer... this conversion costs quite a bit of money and/or time and effort... second is get better carbs like WEBERs or something along those lines, but in order to fit those you'll need a custom intake manifold which don't come cheap either (or at least at where I've been looking) But dead honest truth, the 2.0S wasn't made to be upgraded... if you think finding aftermarket parts for a 3rd gen was hard, find one for the carb version is even fewer.

Anyone happen to know if the B20A3 block could support a B20A5 head? Because I was thinking of looking into doing a motor swap with a JDM B20A and then just upgrade the fuel system but run a carb setup. But then I opted for a FI injection conversion.

TheCecil · 10-31-2002, 09:39 PM

i am sawapping a B20A5 into my S and its not going to be that big of a deal. i am going to start the actual swap in the next few weeks. i finally got my engine back and rebuilt. you'll need a new wiring harness, ecu, dash harness, Si fuel pump and a return fuel line, but thats about it. the hard part is just going to be rewiring the freakin car. but the engine bolts right in, and bolts up to the tranny too. e-mail me if u have any questions bout the swap, im starting it soon.

HPRpreludeSOHC · 11-01-2002, 09:14 AM

I would like to hear how this swap goes, I don't know how much time is actually spent into rewiring the car. But once you have it done, tell us what problems you came across. Do you happen to know if the S has different gear ratios compared to the Si?

Q9erLude · 11-01-2002, 10:23 PM

Anyone try a B18C5R swap? Same weight as a ITR and engine is a hair smaller than the B20A5.

HPRpreludeSOHC · 11-02-2002, 04:55 AM

I think someone tried a B18C swap, but I believe it was off a GSR integra. It wasn't the C5 version but a vtec nonetheless. However, I was told it was hassle but still worth the money. But then again I was thinking...

A smaller engine usually means you save more on gas. But if you put it into a larger, heavier car, wouldn't it eat up more gas because you have to rev slightly higher in comparison to a larger displacement engine to achieve the same amount of acceleration?

I don't think that .2 of a litre would make much of a difference, but yeah. I'm dumb.

merlindavis · 11-02-2002, 07:00 AM

i bet i get better gas mileage with my jdm than i would with a c5... do you really think you could keep yourself out of vtec to save gas? i couldn't.... i think a more acurate measurement of how much gas would be eaten up on a honda would be power output and vtec/non-vtec... a high hp non-vtec would probably eat up as much gas as a mid hp vtec... a c5 should go in without too much trouble... if you are already wired for fi it would just be a matter of the engine harness and ecu... although i'd much rather try it on a car wired for fi from the factory... my $.02

Q9erLude · 11-03-2002, 12:35 AM

The idea of the B18C5R is not to get better gas mileage. It is strictly a performance idea. Like I said, the 3rd gen and ITR are pretty close to the same weight (each weigh 2700 lbs). The B18C5R has more hp and better gearing. As far doing just a B18C swap, might as well get the top of the line B18, the B18C5R.

TheCecil · 11-05-2002, 05:51 PM

well, i am finally starting the swap on my car. the engine is finally back from the machine shop. right now i am starting the prep work for taking the old engine out. oh, only the 1st gear ration is different that the B20A5 tranny. i dont have my helm manual with me right now, but i remember that only the 1st gear ratio is different.

HPRpreludeSOHC · 11-07-2002, 03:43 AM

nice, keep us updated!