Intake Manifolds

**EK1 Civic** · 14-08-2010 09:46 PM

Hi i just want to get this cleared up and i searched around and received different answers.

I heard the d16y8 IM is the same as the d16y4 IM, they look pretty similar. I also heard they aren't the same? Does anyone know?

Was planning to swap mine for the d16y8 is there not the same, seems the Americans swap out there d16y7 IM for a d16y8 as it gives a boost in low-mid range power.

**Mikecivic78** · 15-08-2010 05:23 AM

D16y8 will only give you 5kw (93kw vs 88kw) more than a D16y4. IMO it would be better to save towards a B-series Honda.

**EK1 Civic** · 15-08-2010 12:35 PM

But the part itself costs like $40-50, its like $10 a kw then =D. I don't want a b series or a car with vtec, dont wanna start trashing the car and acting like a dickhead red lining it for the vtec.

**Tai** · 15-08-2010 12:36 PM

Just leave it.

Spend the $$ on suspension mods.

And no changing the IM will not give you 5 kw gain.

there are other parts that contribute to the extra 5kws.

**EK1 Civic** · 15-08-2010 12:40 PM

Yeh i was researching on d series and stumbled somewhere the IMs are the same. And the d16y4 had a lower final drive. Guess ill just stick with i/h/e and a cam regrind while i change my timing belt, needs replacing pretty soon. Anything pretty cheap to do while the rocker cover is off? I heard the valve springs but the d16y4 are pretty strong. I'll be doing a tappet adjustment to match the cam.

**beeza** · 15-08-2010 12:50 PM

There's no gains to be had,they are basically identical.The IACV is on the back of the IM on the y8 where as on the y4 it's on the TB.I think U can can remove the IACV on the y8 plug up the holes but there's no reason to do that unless U had to.

**ekcoupe** · 15-08-2010 12:52 PM

Originally Posted by Mikecivic78

D16y8 will only give you 5kw (93kw vs 88kw) more than a D16y4. IMO it would be better to save towards a B-series Honda.

the y8 im is the same as the y4 im there would be no gains if you swapped them, that extra 5kw is the y8 vtec

**EK1 Civic** · 15-08-2010 12:54 PM

Originally Posted by beeza

There's no gains to be had,they are basically identical.The IACV is on the back of the IM on the y8 where as on the y4 it's on the TB.I think U can can remove the IACV on the y8 plug up the holes but there's no reason to do that unless U had to.

Well the manual y8 has the iacv at the back of the manifold. Its best to purchase an automatic one, where the iacv is on the TB. Then the 98-00 is air injected so u gotta plug the holes up. Thats the key differences that i know of between them.

**beeza** · 15-08-2010 01:00 PM

Gotcha! Upgrading the IM is one of the simpliest things to do to yeild good gains but what IM?

I have seen dodgy ebay ones,just bad designs.

I believe the best the thing to do is modify/bore out the stock y4 one with a dremel.

That's the best way I have found for the y4.

**beeza** · 15-08-2010 01:04 PM

That y8 automatic,is it still a 56mm opening on the TB/IM?

**EK1 Civic** · 15-08-2010 01:10 PM

ye its the same, some ppl say just put a b series tb, as its 60mm and port match with the IM. Just wondering would the car bog down at low rpms? Its my DD and i just want to increase its low-mid power, not its high end.