DarkFlame

Yes, I'm new to this site, but I've put 116k original miles on my '98 Civic LX (D16Y7), and am about to start doing some work. The exhaust manifold is cracked and the CEL led is on.

So, if I'm replacing the exhaust manifold, should I go with stock (to pass the Texas emissions test), or will the 4-2-1 manifolds (& new cat back exhaust) pass the inspection.

I like the quietness of the stock muffler, but don't want anything loud. Still, a performance boost would be an acceptable trade-off, if not too loud.

So, what say you?

grumblemarc

iTrader: (4)

Stock. There is NOTHING you can do to that engine that will increase it's performance. If you want it to be a little more spirited then get an EX transmission.

DarkFlame

So, taking off the entire 13 year old OEM intake & exhaust & replacing them with aftermarket performance parts will have no impact on vehicle performance??? This isn't my first rodeo, I've rebuilt a handful of engines. Why does the Honda Civic LX D16Y7 NOT get any performance boost when changing out the intake & exhaust???

grumblemarc

iTrader: (4)

Because it is a D16Y7 that's why. You will do nothing short of move power around the powerband. The couple of horsepower you will gain, and I mean a couple, will be negated by your grocery getter transmission. And then yu STILL have to get a new catalytic converter and extend the O2 wires.

You're not the first to ask this very same question and you're not the first to disbelieve what I'm telling you but I have collected dyno charts that back me up. This isn't any brutish domestic V6 or V8 where the design of the engine begs for replacement of ultra restrictive parts. These are refined and efficient four bangers from Honda that are designed for economy. Plus I own one so I can tell you first hand.

Do your OWN research if you do not believe me but if you click the link in my signature you will see that i already have.

Bix VT

As marc has said, you will gain less than 5whp for replacing the entire exhaust, which could run you upwards of $500.

The best (read: most cost-effective) solution would be an OEM replacement from a junkyard IMO. If you want to give your car more pep, read up on a "mini-me" swap, or maybe even a B-series engine if you have extra money lying around.

EsotericImage

iTrader: (8)

^^
By the time he spends 2 grand for a swap, he could boost that little sucker and get some real performance..

Either way, he will have to upgrade the clutch, suspension, exhaust and maybe even upgrade to EX front brake set up.

Doing those upgrades will save your life when you have a car with double the power its designed for. boost can be done safely nowadays since the technology has come a long way.

Bix VT

This is very true, and the reason I'm boosting my Y8. It all depends on the budget and power goals. I picked up a full turbo kit from a guy on here for $1100, so that plus neptune/demon and a dyno tune and I'm looking at almost exactly 2 grand end cost, but I would call that a rare deal.

However, a mini-me can be done for much cheaper if he just wants a little extra go.

EsotericImage

iTrader: (8)

50 shot of nitrous is another route to go..

totally safe and will still retain mpgs with power on demand.

grumblemarc

iTrader: (4)

Until the bottle runs out. Who wants to keep refilling a bottle?

Bix VT

I had nitrous on a car I owned a while back...it was a blast, always put a smile on my face. I decided to switch to turbo on every project car since for a few reasons:

1. I got tired of driving 20 miles to fill the tank 1-3 times per week.
2. Each fillup was about $30 back then for a 10lb tank, that's $120-360/month just in happy gas.
3. I got pulled over and searched one day. Not an experience I'd care to repeat.

But if it's a track only car, all of those issues go out the window.

DarkFlame

Ok, this Civic is half of my Daily Driver Brigade, the other half is a Honda motorcycle (Shadow Sabre, 1100CCs, shaft, shield, custom seat, hardbags, full touring setup). I intend to continue driving this thing as long as I can, & figure doing a bit of upgrades while I'm replacing worn parts is a good idea, especially for handling & pep - increasing the fun value of the drive.

Ok, at this point, I'll stick with the exhaust providing very little power or handling benefit. But, if I replace the stock intake and the exhaust, won't I be able to improve on the 25 mpg I'm always getting? No, it's not a track car, and I don't want a track car. I just want to make it a more fun drive.

"mini me" swap? I'll have to figure out what this is. I do not really want to yank the engine. This one, with 116k, is barely broken in.

I am not really interested in doing nitrous (is that "boosting" the car?), and don't really care for turbo. I just figured that if I could bolt on a new intake & exhaust, there ought to be some kind of reason to do that. If there's not, then I simply need to replace the header with something that's not prone to the OEM header crack about which I've been reading so much.

Also, I guess a diff auto tranny from an EX might be a good idea.

On the other hand, when I'm really wanting to build a fun car, I guess I'll pick out one of the Civics with a little more "tuner" in it - & with a standard transmission.

DarkFlame

I did click the link - the one about making your Civic go faster. "Mini me" is apparently a head swap. I think I'd rather swap a full engine, or tranny.

This is not the first forum I've joined, and am quite active on a Honda Shadow forum as well as a Woodworking forum. I am reasonably sure that any question I might ask about fixing and/or upgrading my vehicle, as it's needed, has already been asked thousands of times before.

Looks like turbo would be the best way to up the performance of my engine, and should not include any prior alterations to the intake or exhaust as they will need to be redone for the turbo.

The one thing your article does not mention is whether a chip swap is worthwhile.

I'm learning as I'm going, and I appreciate the candor of your response.

I snapped a pick of my car today. Now I just need to upload it from my phone, to my file server, to my web server, and then I can link to it from the forum.

HondaPartsHero

Here's some examples from googling for Y7 dyno charts, from another link it looks like a baseline graph for a stock Y7 is around 98 whp so here ya go:

Y7 with more than moderate bolt ons (118 whp):
http://www.d-series.org/forums/natur...yno-sheet.html

Y7/Y8 head (199 whp):
http://www.htarchive.com/showthread.php?t=2718815

Its really not worth anything you do to it, even the EX transmission doesn't make it feel that much better. I have a 96 DX with the Y7 with an EX transmission and while it does make it a bit more peppy its not really worth it.

grumblemarc

iTrader: (4)

You cannot "chip swap" this car.

redm3turbo

y7 is the economy engine...thats why you can throw money at it and not get anywheres, however 25mpg isn't good enough. I have a y7 and consistently get 34 mpg.

It doesn't sound right, but really nothing wakes the y7 up. Its great at its job, and that job was economy. Get her running tip top and enjoy the slow yet fuel efficient motor.

EsotericImage

iTrader: (8)

you can just replace the cracked mani with a set from ebay. Its not going to do much, but will fix your issue.

DarkFlame

& that's pretty much exactly where I started. So, for this engine, in this car, the intake & exhaust stay stock. I like the sound of that.

And, as long as we're considering options, what about an engine swap? Do ALL the engines attach at the same mounting points in each model? And, with this car, WHAT other engines will fit - esp those that would offer a few more ponies under the hood?

Bix VT

http://krang.modified.com/tech/swapguide1.pdf

I personally like the idea of an LS motor with a Vtec head (LS-V) since it's great for turbo. But if you want to stay NA you may want to look into a larger displacement engine for better torque.

NotAJDMFanBoy

To pass emissions, you would need the Y8 catalytic converter, and by moving it farther from the engine, the catalyst won't warm up as fast. I would go ahead and convert it just because the Y7 manifold is known so well for cracking. If you have access to it or know someone who can, a TIG welder and nickel wire could be used to repair the manifold you have, but that requires preheating and post heating and if not done right, it may just crack worse or just not last. And there's nothing saying a new manifold won't just crack later anyway.

As for extending the O2 sensor wires, soldering isn't that hard. And they sell extension harnesses.

I think the issue is the design of the manifold and possibly not thick enough material. Cast iron is brittle and they didn't include any way for it to flex as it expands. It's just not an ideal design.

Hardrath_R

Swap her and boost it! In the long run you will save more money and will have more fun

EsotericImage

iTrader: (8)

DarkFlame

You make a lot of sense. I figure the cracked exhaust manifold is such a common ... experience - I'd call it a "defect" & Microsoft would call it a "feature," ... that neither fixing it nor replacing it with the same thing (ESP one from a junkyard!) would provide sufficiently reasonable results.

So, what you're saying is that the best I can do is to get an exhaust manifold and catalytic converter from a D16Y8 engine instead of from my D16Y7, and lengthen the wires on the O2 sensors ("I've cut them 3 times & they're STILL too short!") so that they'll reach? This is a viable long-term solution? (I mean, that's easy enough to do).

Are there any "warm up" issues with the converter further away from the exhaust ports?

Even tho my FIL can weld cold bubblegum to a greased watermelon, I am of the mind that repairing it is not a good idea. IF I were to repair it, I'd probably try JB Weld, which eliminates all that pre/post heating minutia.

As for a Cat Back exhaust, will those pass inspection in Texas (not concerned about California)? I'm asking because this is still the original exhaust, 116k miles on it. I wouldn't mind replacing it. But, if anything other than the OEM results in no extra ponies, just a redistribution of the power curve, then I should do the OEM (or similar replacement).

DarkFlame

So, the D16Y7 is what it is, and they're getting everything out of it that goes into it, making it pretty efficient. I like that. ... BUT, if I were going to REPLACE the engine, and trans, is the D16Y8 (US:EX) a direct bolt-in (no mounting mods)? What about the B16A2 (US:Si)? Will the B16A2 mount up to the LX or EX transmissions? (The last thing I want to do to a car is convert it from auto to standard - I LOVE driving standard, but I don't want to bother with the conversion, linkage, interior, etc.)

I'm learning a LOT about my car! This is GREAT!!!