i have a crx si and im getting an 89 civic dx hatch for free. the tranny is bad but im gonan use the engine on my crx but with all the si goodies. whats this engine have stock? what about with the asi stuff will it be faster than a real si b.c of the comprewssion differences? ill have nore questions after i pick it up

 

A D15B2 with the Si intake manifold and Si computer won't make the power that the D16A6 has stock. Because, think about this; its the same setup with less displacement, and a weaker cam. Sure the D15 block is shorter than the A6, but the D15 rods are also shorter. The C/R on either car is about the same (I'm not for sure what it is on either car).

 

im gonan use the si cam.. all the si stuff, just dx head and block

 

Its still not going to be quite as powerful because of the amount of displacement. It'll feel basically like the same engine though. I have the A6 cam and rocker arms in my B7 and the engine pulls pretty hard, especially for what it is.

 

For what it's worth
get a die grinder, do a quick P&P on the head (gasket matched of course), then take a stock head gasket and strip it down to 1 layer to raise compession. Might gain you some hp if it's a low budget project anyway. or spend $80 to have the head shaved.

the extra compression and better flow will make up for lost displacement and could easily get you the 108 flywheel hp output of the A6.

 

you could always find a d16y7 head for very very cheap, seeing as how these are thrown away more than anything else.. with d16z6 sized combustion chambers and larger valves than the OBD0 engines, a d15 block with d16y7 head will be around 9.8:1 compression.

 

i have a 4th gen DX

DX = Slow

 

i have a 4th gen too...mpfi done to it...its ok...not HELLA slow...but its gone...d16z6 is my best friend now

 

this statement pretty much sums up the majority of civic's

Slow unless Swapped

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nuc79 &raquo;</TD></TR><TR><TD CLASS="quote">For what it's worth
get a die grinder, do a quick P&P on the head (gasket matched of course), then take a stock head gasket and strip it down to 1 layer to raise compession. Might gain you some hp if it's a low budget project anyway. or spend $80 to have the head shaved.

the extra compression and better flow will make up for lost displacement and could easily get you the 108 flywheel hp output of the A6.</TD></TR></TABLE>

wtf are you talking about? if you wanted higher compression you would get a thicker head gasket. and everybody can't just pick up a grinder and do their own P&P, it's not that simple. don't listen to this guy. just use the Si intake mani, the Si cam, and Si ecu, and you will have almost as much power.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheBestCRX &raquo;</TD></TR><TR><TD CLASS="quote">

wtf are you talking about? if you wanted higher compression you would get a thicker head gasket. </TD></TR></TABLE>

You sure on that, I thought thicker meant lower CR.

 

thick means low, thin means high, the less area for air to go, the higher the compression

 

And with the thicker head gasket, there is more area for the air to go, therefore lowering compression.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheBestCRX &raquo;</TD></TR><TR><TD CLASS="quote">

wtf are you talking about? if you wanted higher compression you would get a thicker head gasket. </TD></TR></TABLE>

One of the most important factors in engine building is determining your engine’s final compression ratio. Compression ratio (C/R) has far reaching effects on the performance of any internal combustion engine. If the C/R is too low, you’ll have a real dog on your hands. Too high and you won’t be able to run pump gas without incurring pre-ignition and destructive detonation. Ignore the C/R and you could be in for a very unpleasant surprise.

Remember what happens during the compression stroke of the four-stroke cycle: Both the intake and exhaust valves are closed so no air can escape, and the piston moves upward from bottom dead center (BDC) to top dead center (TDC) so that the air/fuel mixture in the cylinder is compressed into the combustion chamber. Compression ratio is the relationship of cylinder volume (or displacement) with the piston at BDC to cylinder volume with the piston at TDC. If the volume of the cylinder with the piston at BDC is 10 times greater than the volume of the combustion area with the piston at TDC, then 10 units of volume get squeezed into 1 unit of space, and the compression ratio is 10.0:1.

There are five factors that affect compression ratio: cylinder swept volume, clearance volume, piston dome or dish, head-gasket volume, and chamber volume.

Head-gasket volume is determined by the compressed thickness of the gasket. A thicker gasket adds volume and reduces compression; a thinner gasket reduces volume and increases compression.

You're right, I must not know what I'm talking about But seriously, I guess the statement about head porting should be retracted. It takes a little bit of skill and/or experience, and shouldn't be taken lightly.