1998 Civic LX to HX D16y5 conversion has begun!

[firehawk618]

Oh the date code is what you were talking about?

[Xist]

Good luck!

[firehawk618]

Valve guide seals replaced, engine stripped down as far as I am taking it.

Now waiting for new parts to arrive.

If all goes as planned I should have it in and running by Thursday.

[firehawk618]

Head installed, valves clearanced *boy were they all tight*, oil pan cleaned and installed, water pump and timing set installed.

Dismantled the intake. All but one egr passage was totally blocked. Cleaned it all up good. Even all the snake passages were full. There's no way this engine wasn't throwing a cel not to mention no lean burn as a penalty.

Idle air valve screen was also completely blocked.


Tomorrow will be re install the wiring harness and intake.

After that it's time to pull the d16y7.

On track to have it running by Friday.

*forgive spelling errors this is all posted from my phone.

[darcane]

Originally Posted by firehawk618

Apparently from my research the LX/DX can have one of two final drives. The sedan has a lower geared one vs the coupe/hatch.

This is correct.

Honda transmission gearing:
http://ecomodder.com/forum/showthrea...ios-26279.html

HX would have the same gearing and FD as an LX/DX hatch (FD= 3.722:1)
Your LX Sedan has the same gear ratios, but a lower FD (FD=4.058:1)

For all the work you are putting into this car, I think leaving in your LX tranny is being shortsighted. The HX would give you about an 8% drop in RPMs, 5th gen CX/VX tranny would be about 20% drop.

[Xist]

Doesn't lean burn require higher RPMs?

[Chrysler kid]

Originally Posted by darcane

This is correct.

Honda transmission gearing:
http://ecomodder.com/forum/showthrea...ios-26279.html

HX would have the same gearing and FD as an LX/DX hatch (FD= 3.722:1)
Your LX Sedan has the same gear ratios, but a lower FD (FD=4.058:1)

For all the work you are putting into this car, I think leaving in your LX tranny is being shortsighted. The HX would give you about an 8% drop in RPMs, 5th gen CX/VX tranny would be about 20% drop.

It really depends on driving style. If this is a long commuter all highway miles very few stops he would see more benefit from the taller gearing and steelies with disc covers

If this is a mixed city and highway driving there really is not much point. City driving you would want shorter gears and the light weight wheels from a hx or vx to require less effort to accelerate.

With my d15b s40 lsd trans on my hx this winter I'm getting 36.8 mpg all city driving. Lean burn kicks in at 52mph and with 45mph speed limits I can usually hit a clean lean burn atleast once on my trips for a few minutes

There is also a thread back in the depths of this forum where a hx member did install a vx trans into his car, I believe he was hoping to turn 2k rpms at 60mph similar to a vx model but noticed he was still turning close to 2200 rpms. He concluded that the trans swap which he intended as an upgrade was more work than it was worth and didn't really net him any benefit.

Lean burn is rpm and speed sensitive on the hx ecu. It only engages in final gear during certain conditions above 2300 rpm or 55mph-78mph. There was also a member who did install a few resistors into his vss sensor to trick the ecu but again I don't recall him updating his posts or fuel log after that

Now if his factory lx trans is on the way out then I would say yes to swap them but he hasn't mentioned that

[Xist]

Balto did that, but when I did a quick search, I did not find anything relevant. I just remember that he disliked the gearing and could not get into lean burn at reasonable speeds.

[Chrysler kid]

Originally Posted by Xist

Balto did that, but when I did a quick search, I did not find anything relevant. I just remember that he disliked the gearing and could not get into lean burn at reasonable speeds.

Yeah I know he had a build thread about the vx trans swap and he didn't have anything positive to say about it. Half the time with my short gear trans I just shift first third fifth to keep the engine over square and use torque to accelerate

[firehawk618]

Originally Posted by darcane

This is correct.

Honda transmission gearing:
http://ecomodder.com/forum/showthrea...ios-26279.html

HX would have the same gearing and FD as an LX/DX hatch (FD= 3.722:1)
Your LX Sedan has the same gear ratios, but a lower FD (FD=4.058:1)

For all the work you are putting into this car, I think leaving in your LX tranny is being shortsighted. The HX would give you about an 8% drop in RPMs, 5th gen CX/VX tranny would be about 20% drop.

I really question the accuracy of the 6th gen civics because.

1. There was no EX hatch.
2. When you check interchanges for the HX transmission it is exclusive to the HX only.

I have an EX transmission in my car now. It's most definitely NOT the same ratio as the DX trans as that reference says.
The trans I originally removed from my car was the stock one.

Either way, it's not hard to swap out transaxles later so if I am not satisfied with the DX ratio / FD combo I will find a HX or VX to try out.