EK1 Monster

[Tropic81]

After years of hibernation, I've gotten the itch to work on my EK1 again. Originally, the engine was in a '79 Accord, buy i may put it in my '81 convertible Prelude. List of mods:
1. EL head from AT Engineering;
2. 2 mm oversized valves;
3. Silicon bronze valve guides;
4. Titanium spring retainers with stiffened valve springs;
5. Shaved .30;
6. Port matched;
7. .420 lift, 296 degree cam;
8. Block bored .30 over;
9. Forged pistons w/ chrome moly rings (AT Engineering);
10. Forged aluminum rods (AT Engineering);
11. Lightened flywheel;
12. Dual Weber side draft manifold;
13. 4-2-1 header.

Now, I also have a turbo setup for the engine. It's possible that it is an old Jackson Racing setup, but I'm not sure. It's currently configures as a draw through using a Garrett Airresearch M-11.

I'm considering use of the turbo setup with the dual Weber side drafts. Not sure if I should continue with the draw through configuration or convert to a blow through. Either way, it should be insane.

Thoughts...?

[Tropic81]

BTW... the Prelude is a Tropic conversion. It has been lowered with King Springs and Koni adjustable struts. Addco sway bars front and rear. Cross-drilled Brembo front disks and EBC "green" pads. Rounding off with the body kit from Design Auto out of Germany.

[Shane86]

After years of hibernation, I've gotten the itch to work on my EK1 again. Originally, the engine was in a '79 Accord, buy i may put it in my '81 convertible Prelude. List of mods:
1. EL head from AT Engineering;
2. 2 mm oversized valves;
3. Silicon bronze valve guides;
4. Titanium spring retainers with stiffened valve springs;
5. Shaved .30;
6. Port matched;
7. .420 lift, 296 degree cam;
8. Block bored .30 over;
9. Forged pistons w/ chrome moly rings (AT Engineering);
10. Forged aluminum rods (AT Engineering);
11. Lightened flywheel;
12. Dual Weber side draft manifold;
13. 4-2-1 header.

Now, I also have a turbo setup for the engine. It's possible that it is an old Jackson Racing setup, but I'm not sure. It's currently configures as a draw through using a Garrett Airresearch M-11.

I'm considering use of the turbo setup with the dual Weber side drafts. Not sure if I should continue with the draw through configuration or convert to a blow through. Either way, it should be insane.

Thoughts...?

Welcome i like to see some pictures of the project

[Tropic81]

Welcome i like to see some pictures of the project

Thanks. I've been dormant for a long time. I can post some pics of the engine setup. The car is disassembled now.

[Shane86]

Thanks. I've been dormant for a long time. I can post some pics of the engine setup. The car is disassembled now.

I would like to see the engine

[tof]

I would like to know how long you've been holding on to these parts. Amazing.

[Oldblueaccord]

Funny I just saw one about a month ago at a car show here. At least im pretty sure. By the time I got parked the guy has left.

BaT Exclusive: 1981 Honda Prelude Solaire | Bring a Trailer


I didnt remember the name of the conversion at the time Thanks!

[tof]

Yeah. I didn't even know these were a thing and suddenly they are everywhere...at least on the Internet.

[Honda#1]

Wow! I'd love to see one in person. A head turner. And not for everyone especially with all the attention you're gonna get. I get a lot of attention in my EK1 already and its just a gray hatchback but people stare at it.

[Tropic81]

I got the Prelude in 1990. It original engine still only has 55k on the clock. As for the other engine, it was from a "79 Accord. The build started with a blown head gasket around 1991. I've been collecting parts ever since. By the time I finished the engine, it made my Accord faster than my "91 CRX Si and that was without the dual carbs or turbo.

[79cord]

Sounds spectacular.
Guess you'd know crank/flywheel bolts changed from 10 to 12mm late in '80, just so you don't lighten the wrong flywheel.
And for others Tropic was the German conversion company, with some others in the US doing their own conversions. So other convertible conversions weren't known as Tropics.

[Tropic81]

Sounds spectacular.
Guess you'd know crank/flywheel bolts changed from 10 to 12mm late in '80, just so you don't lighten the wrong flywheel.
And for others Tropic was the German conversion company, with some others in the US doing their own conversions. So other convertible conversions weren't known as Tropics.

You are absolutely right about the bolts on the flywheel. I found out the hard way. Tropic was a company in Crailsheim Germany and they did 47 conversions. Solaire also did conversions, but I don't know how many. I was lucky enough to get one of the German conversions. They did a nice job with adding frame bracing to compensate for the loss of rigidity after cutting off the roof. I just lost interest for a long time, but have recently gotten back into it. My original top is a mess so I bought I top and frame from an old SL Mercedes. They are so similar that I think I can make it work fairly easily.

[Tropic81]

I really thought about doing B18 conversion and maybe I will some day, but I would honestly love to see how good the EK1 does.

[tof]

If and when you ever do a B-series swap, if the EK1 is still strong please let me know. Heck, even if it's blown.

[AWH]

https://thisoldhonda.org/classifieds...cars-for-sale/

I think this is another one of the same series. For sale.

Auke.

[Tropic81]

That's a pretty decent looking Prelude, but I don't think it is a Tropic. The plaque stating Continental Honda isn't from Tropic and the top is different. Tropic conversion have 3 window panes instead of 1. Of course, it could be a custom top made to replace the original, but that plaque still causes doubt. I'm guessing they said it was 1 of 47 based on some research into the Tropic model.

[79cord]

I wonder what they were thinking with that stupidly small rear window, even a bigger glass window could be stowed easily!
There was even a Solaire based conversion sold here in Australia last month, apparently converted here in '81 with the assistance of Bruce Meyers (VW Beach-buggy fame) who had conceived the Solaire conversions.

Found out about the crank/flywheel bolts (& floor & shift linkage & driveshafts & frt Hubs) after buying Sept'80 Prelude parts-car for 5-speed conversion of my Nov'80. Nov was already '81 Model year.

[chuck d]

hi, Where did you find a Jackson racing EK1 Turbo ??? and Where can I get one ?

[Shane86]

hi, where did you find a jackson racing ek1 turbo ??? And where can i get one ?

x2

[Tropic81]

x2

I don't think it is a Jackson Racing setup although I could be wrong. I just stumbles upon it and the guy didn't know much. It's a draw through setup for a single carb. I was thinking about modifying it for a blow through for dual sidedrafts.

[dedens]

Tropic81,

I have a 1983 Honda Accord. I am collecting the parts for an EK1 build this winter. I too plan to use the EL 1602 no CVCC head (I assume this is the head you used). Do you have a contact name at AT Engineering? Which header and exhaust did you use? I can't see to find anything. This week I am converting to the Weber K725 as the OE carb took a dump and I failed to rebuild it last weekend. Any help would be much appreciated.

Derek

[2ndGenGuy]

For the EL head, you need to make sure it matches the same year as your engine. There are 3 EK1 engines...

78-79ish with the 2 port exhaust
80-81 with the 4 port exhaust
82-83 with redesigned port layout

The 82-83 head will not bolt onto the earlier engine blocks.

I'm pretty sure AT Engineering is long gone. Any parts left over from them are super rare.

[dedens]

For the EL head, you need to make sure it matches the same year as your engine. There are 3 EK1 engines...

78-79ish with the 2 port exhaust
80-81 with the 4 port exhaust
82-83 with redesigned port layout

The 82-83 head will not bolt onto the earlier engine blocks.

I'm pretty sure AT Engineering is long gone. Any parts left over from them are super rare.

I have a 83 EK1 motor. I have not been able to find a 1.6L head. That said, I might have to keep with the CVCC 1.8L head but still do the build. Other thought is to transplant a B18 Non-VTEC from an LS Integra. Not sure yet...I go back and forth as engine parts for the EK1 are getting harder and harder to find but the B18 swap would require extensive fab work. Thoughts

[2ndGenGuy]

You won't have a super easy time finding a head. But every Canadian Accord was non-cvcc, so you don't have to look too far, or know Japanese to find one.

To be honest, I don't think you'll notice a ton of difference between the CVCC head and the non-cvcc version on the same engine. They say those heads bumped compression, but I'm not sure by how much exactly.

There are quite a few B18 swaps out there. It's definitely going to make you more power than even a built EK1. And probably better gas mileage at the equivalent power. Like, if you were able to build an EK to 140hp, it's probably going to be sucking down some gas, not to mention some drivability. I could be wrong though...

Either way, it's going to be work.

[dedens]

Thank you for the response. I reached out to a reputable Honda Performance shop. I am in talks to have them do the B18 swap. Stay tuned