seancornelis
03-20-2006, 04:30 AM
***DISCLAIMER: I do not claim any of this information to be 100% accurate as most of it is typed from memory of research I did on modifying the EK engine over four years ago. This is only intended as a rough draft and hopefully we can get some other info together and eventually make an EK section a part of the FAQ. If you are mislead because of any of this information I am sincerely sorry and do not recommend you attempt anything in this thread without doing further research on your own. IF ANYTHING CONTAINED HERE IS INACCURATE LET ME KNOW AND I WILL CORRECT IT**
I'm still loving that 3geez.com finally added these sections, as a matter of fact in the last couple days I've spent most of my free time reading through all of the threads in the 1/2g sections....but it seems as if a lot of people see the EK as a dead end as far as performance goes, whereaes the 84-85 models have the convenience of being able to take an A-series engine and a whole other world of performance parts.
While that's definitely true (EK is much more limited) there are some options, and at one time there was a decent amount of aftermarket support for these motors. There was a time when Jackson Racing and A/T Engineering catalogs were filled with parts for these with everything from swaybars to full turbo kits.
I'm just gonna rack my brain here and see what I can remember from my EK1 owning days, keep in mind I've never modified one in any way (just fixed em when they broke!) but I've done pretty heavy research so hopefully someone can take what I provide to the next level...
First off, these are all true E-series motors, descendents of the original EB 1200cc all aluminum motor in the 1973 Honda Civic. The ES series motors (84-85) are entirely different and basically early A-series. The only direct swaps are the earlier E-series (EB,EN,EG,EJ,etc,etc.) but those are all smaller displacement and less horsepower so I have no idea why you'd want one. There is at least one motor that is a direct swap that produces significantly more horsepower....but I'll get into that later as it's tricky.
There's (at least) 2 types of EK1 motor, the 79-81 (Accord/Prelude) 2 port exhaust head and the 82-83 (Accord) 4 port exhaust head. While nearly identical, externally, the oil and coolant passages between the block and head do not line up at all nor do the ports for the intake/exhaust manifolds so they're technically two different engines. The four port motor is good for a whole 3 HP more, stock, than the older one. There was also a JDM EK motor (not EK1) that was claimed as having 97HP stock although I know nothing about it whatsoever. The EK1 in the 82 Prelude (1st gen) I also know nothing about and am not sure if it was a 2p or 4p or some kind of total freak.
Stock specs are:
2port: 1751cc(77x94) 8.0:1 72HP@4500rpm / 94lb.ft@3000rpm
4port: 1751cc(80x79.5) 8.8:1 75HP@4500rpm / 96lb.ft@3000rpm
Both redline at 6000rpm and have CVCC heads....which is what I'll get into right now.
First order of business when modifying an EK should be upgrading to the EL (1602) head. This is the crossflow, non-CVCC head that came on 79-83 1.6l non-USDM Accords/Ludes. In the states, our closest source for these is Canada where they seem to be fairly common, although sourcing one might be tough without a connection up north. This is a direct swap, although you need to right EL head relative to your year - 79-81 EL is 1602cc and 82-83 is 1598cc. Not only will these flow much better and slightly bump compression, but they also are much less complicated and less prone to overheating. As with anything, a good shop can port/polish. Larger valves can be done but are expensive since they have to be custom made. I don't know what you can swap on the bottom end of things, but a 2v crank in a 4v block would make one hell of a stroker, which I just realized. No clue about this however. Of course the EK can be bored out as well, but I wouldn't go too far with it.
In 2002 there was a company still building cams for the EK1 but I'll be damned if I can remember their name anymore....they did have a website so if I come across it, I'll definitely post it here. In any case, it's probably even cheaper to have your cam reground to whatever specs you like, just find a quality shop.
Getting back to the "bolt on" ends of things....
There were at one time several kinds of headers available, Jackson Racing, A/T, Pacesetter and S&S being the bigger names although there were also some long since defunct brands out there. A couple years ago there was a "Hondo" (actual brand, not a misprint) header for the 82-83 EK1 that went for a whole $23 on Ebay, brand new in the box.
Dual carb manifolds also existed from a variety of sources (mostly the same listed above) so Deltoros, DCOES, Mikunis, etc. are all possible although this may be the hardest item to locate of all. I've seen a handful of 1st gen Civics running EL/EK motors with these on the web so they do still exist (scroll down to the end of this post for a link to 1st gen Civic info). I also remember someone telling me that the early EL head has the same port spacing as the ES1 dual carb motor from the 2nd gen Prelude, although I have no clue how factual that is. Those carbs aren't the greatest things in the world in performance terms, but that motor was good for 100hp (same displacement) and I owned one and never had any problems with the carbs whatsoever. Ran smooth and pulled hard.
Weber 32/36 is of course do-able and last time I checked, full kits were still available from a few sources (that was 4 years ago though, so again sorry if I'm wrong). If you want to upgrade your carb and don't plan on doing much else, this is definitely the way to go. If you wanna do a little rebuilding and fabricating of your own, used carbs can usually be had for a song as well - this is one of the most popular aftermarket carbuerators out there.
If you want a completely different method of fuel delivery however.....there was at one time a company called Mosselman that built a Fuel Injection kit for these motors. It was all mechanical and based off the early VW Rabbit system. Insanely rare and in all likelihood a piece of crap, but I just figured I'd throw that out there.
Custom built TBI injection wouldn't be THAT hard, however. A TBI system fits the motor in the same way a single downdraft carb does, however it's a computer controlled single injector system. To get this running, you would need a donor TBI system (best bet probably being the 4th gen Civic or a GM TBI system from a J-body 2.0l motor) an adapter plate to fit on your manifold (can be easily fabricated) an EFI pump, a return line ('85 SEi), a modified distributor (if you want spark control as well) and hours and hours of patience with wiring, tuning and adapting sensors. From a performance standpoint, all this work wouldn't give you huge gains - but it would improve driveability immensely. Plus it'll allow you to run a pretty wild cam without sacrificing as much fuel economy or idle quality. This is only an idea I've gotten in my head recently and if anyone is interested I can go into it a little more because in reality it is more complicated than I'm making it seem.
I'm still loving that 3geez.com finally added these sections, as a matter of fact in the last couple days I've spent most of my free time reading through all of the threads in the 1/2g sections....but it seems as if a lot of people see the EK as a dead end as far as performance goes, whereaes the 84-85 models have the convenience of being able to take an A-series engine and a whole other world of performance parts.
While that's definitely true (EK is much more limited) there are some options, and at one time there was a decent amount of aftermarket support for these motors. There was a time when Jackson Racing and A/T Engineering catalogs were filled with parts for these with everything from swaybars to full turbo kits.
I'm just gonna rack my brain here and see what I can remember from my EK1 owning days, keep in mind I've never modified one in any way (just fixed em when they broke!) but I've done pretty heavy research so hopefully someone can take what I provide to the next level...
First off, these are all true E-series motors, descendents of the original EB 1200cc all aluminum motor in the 1973 Honda Civic. The ES series motors (84-85) are entirely different and basically early A-series. The only direct swaps are the earlier E-series (EB,EN,EG,EJ,etc,etc.) but those are all smaller displacement and less horsepower so I have no idea why you'd want one. There is at least one motor that is a direct swap that produces significantly more horsepower....but I'll get into that later as it's tricky.
There's (at least) 2 types of EK1 motor, the 79-81 (Accord/Prelude) 2 port exhaust head and the 82-83 (Accord) 4 port exhaust head. While nearly identical, externally, the oil and coolant passages between the block and head do not line up at all nor do the ports for the intake/exhaust manifolds so they're technically two different engines. The four port motor is good for a whole 3 HP more, stock, than the older one. There was also a JDM EK motor (not EK1) that was claimed as having 97HP stock although I know nothing about it whatsoever. The EK1 in the 82 Prelude (1st gen) I also know nothing about and am not sure if it was a 2p or 4p or some kind of total freak.
Stock specs are:
2port: 1751cc(77x94) 8.0:1 72HP@4500rpm / 94lb.ft@3000rpm
4port: 1751cc(80x79.5) 8.8:1 75HP@4500rpm / 96lb.ft@3000rpm
Both redline at 6000rpm and have CVCC heads....which is what I'll get into right now.
First order of business when modifying an EK should be upgrading to the EL (1602) head. This is the crossflow, non-CVCC head that came on 79-83 1.6l non-USDM Accords/Ludes. In the states, our closest source for these is Canada where they seem to be fairly common, although sourcing one might be tough without a connection up north. This is a direct swap, although you need to right EL head relative to your year - 79-81 EL is 1602cc and 82-83 is 1598cc. Not only will these flow much better and slightly bump compression, but they also are much less complicated and less prone to overheating. As with anything, a good shop can port/polish. Larger valves can be done but are expensive since they have to be custom made. I don't know what you can swap on the bottom end of things, but a 2v crank in a 4v block would make one hell of a stroker, which I just realized. No clue about this however. Of course the EK can be bored out as well, but I wouldn't go too far with it.
In 2002 there was a company still building cams for the EK1 but I'll be damned if I can remember their name anymore....they did have a website so if I come across it, I'll definitely post it here. In any case, it's probably even cheaper to have your cam reground to whatever specs you like, just find a quality shop.
Getting back to the "bolt on" ends of things....
There were at one time several kinds of headers available, Jackson Racing, A/T, Pacesetter and S&S being the bigger names although there were also some long since defunct brands out there. A couple years ago there was a "Hondo" (actual brand, not a misprint) header for the 82-83 EK1 that went for a whole $23 on Ebay, brand new in the box.
Dual carb manifolds also existed from a variety of sources (mostly the same listed above) so Deltoros, DCOES, Mikunis, etc. are all possible although this may be the hardest item to locate of all. I've seen a handful of 1st gen Civics running EL/EK motors with these on the web so they do still exist (scroll down to the end of this post for a link to 1st gen Civic info). I also remember someone telling me that the early EL head has the same port spacing as the ES1 dual carb motor from the 2nd gen Prelude, although I have no clue how factual that is. Those carbs aren't the greatest things in the world in performance terms, but that motor was good for 100hp (same displacement) and I owned one and never had any problems with the carbs whatsoever. Ran smooth and pulled hard.
Weber 32/36 is of course do-able and last time I checked, full kits were still available from a few sources (that was 4 years ago though, so again sorry if I'm wrong). If you want to upgrade your carb and don't plan on doing much else, this is definitely the way to go. If you wanna do a little rebuilding and fabricating of your own, used carbs can usually be had for a song as well - this is one of the most popular aftermarket carbuerators out there.
If you want a completely different method of fuel delivery however.....there was at one time a company called Mosselman that built a Fuel Injection kit for these motors. It was all mechanical and based off the early VW Rabbit system. Insanely rare and in all likelihood a piece of crap, but I just figured I'd throw that out there.
Custom built TBI injection wouldn't be THAT hard, however. A TBI system fits the motor in the same way a single downdraft carb does, however it's a computer controlled single injector system. To get this running, you would need a donor TBI system (best bet probably being the 4th gen Civic or a GM TBI system from a J-body 2.0l motor) an adapter plate to fit on your manifold (can be easily fabricated) an EFI pump, a return line ('85 SEi), a modified distributor (if you want spark control as well) and hours and hours of patience with wiring, tuning and adapting sensors. From a performance standpoint, all this work wouldn't give you huge gains - but it would improve driveability immensely. Plus it'll allow you to run a pretty wild cam without sacrificing as much fuel economy or idle quality. This is only an idea I've gotten in my head recently and if anyone is interested I can go into it a little more because in reality it is more complicated than I'm making it seem.