ok here is the situation. i have a boosted crx that i love but its not the best people mover. so sometime soon i want to pick up an EF 4 door or maybe even a hatch and use as a DD. so right now i am going to start and put together a motor that i want in it

ok so heres what i have in my garage
Y8 head
d15b motor out of my hf with mpfi harness
another si trans
and enough other parts to build another

now my questions to HT are
can i put the y8 head on the D15b6 block to make some kind of a mini me??
is there anything i can do to the block at all, like ls rods or oem pistons to raise compression??
is this block similar or the same to the d16a6??

sorry for the long post and any input would be great and thanks for all you help in advance

 

does any body know??

 

the hf pistons only have 2 vavle indentions(dont know technical name) since its an 8 valve motor. And im pretty sure the rods are alot smaller and weaker.
personally i wouldnt use that bottom end at all.

 

yes you can put on the y8 head on the d15 block...but you gotta either go obd1 or get the conversion harness if you want to stick with your obd0 ecu.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 290allen &raquo;</TD></TR><TR><TD CLASS="quote">the hf pistons only have 2 vavle indentions(dont know technical name) since its an 8 valve motor. And im pretty sure the rods are alot smaller and weaker.
personally i wouldnt use that bottom end at all.</TD></TR></TABLE>

This is correct information. you CANNOT put a 16 valve head on an 8 valve block without changing out the pistons. The reason for this is d15b6 block's pistons have only 2 valve reliefs instead of the needed 4. if you dont swap the pistons, you will ruin the head.

If you want to build up the d15b6, you could swap in SI connecting rods and pistons, which will then allow you to run the vtec head without issues.

edit: a correction was made to the connecting rod statement i made below.. disregard my statement.


Modified by sanimalp at 12:18 AM 5/30/2008

 

you can't use Si rods in a D15B6 - the crank journals for the rods in the B6 are 38mm (41mm rod big end) and in the Si, they are 45mm (48mm rod big end)

 

thanks for the info guys .. i guess i will have alot of work ahead of me if i try to do this i might as well try and find a d16a6 block

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jlicrx &raquo;</TD></TR><TR><TD CLASS="quote">you can't use Si rods in a D15B6 - the crank journals for the rods in the B6 are 38mm (41mm rod big end) and in the Si, they are 45mm (48mm rod big end)</TD></TR></TABLE>

Gotcha... didnt know that. can you use the SI crank in the b6? or is it just all wrong?

 

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

Gotcha... didnt know that. can you use the SI crank in the b6? or is it just all wrong? </TD></TR></TABLE>Si crank has 55mm main journals - B6 has 45mm