i was looking at the stats of a gsr motor and a si motor. they both have the same bore of 81.0 mm. but the gsr has a stroke of 87.2mm while the si has a stroke of 77.4. hence the displacement difference.

a poor man type r motor is a b16 head+gsr bottom+pistons

can i just swap a gsr crank into a b16 motor to gain the displacement (to get same power as a poor mans typr r power), or is there a difference in deck height? or is there something else im missing? is there any weaknesses of just swapping out the crankshaft vs. the whole gsr bottom?

so what would be better i am on a budget???

option 1: build the poor man type r or option2: just swapping out to a gsr crank



Modified by DImages56 at 12:40 AM 9/27/2006

 

You'd be better off with whichever crank has a larger offset. I don't know the numbers off hand but that would be better...for compression anyway.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DImages56 &raquo;</TD></TR><TR><TD CLASS="quote">
a poor man type r motor is a b16 head+gsr bottom+pistons
(the poor man type r needs pistons because of the loss compression with the swapped block.)

can i just swap a gsr crank into a b16 motor to gain the displacement (to get same power as a poor mans typr r power), or is there a difference in deck height? or is there something else im missing? is there any weaknesses of just swapping out the crankshaft vs. the whole gsr bottom?

so what would be better i am on a budget???

option 1: build the poor man type r or option2: just swapping out to a gsr crank
</TD></TR></TABLE>

i don't get what you are saying about the pistons for the poor man's type r?
i thought GSR(B18)+B16 head= poor man.
the pistons have nothing to do with it.

also, you just can't swap out cranks. i believe there is a deck difference as well.

 

Ok the "poor mans type r" is just a GSR block and B16A head. You will only loose about .2 point of compression as the PR3 casting head has the domed combustion chambers and the P72 castings have the pentroof design.

You would be better off just buying a GSR engine as you have the 1.8L of displacement, no compression loss AND slightly more aggressive cams. Just run a better throttlebody, intake manifold set-up and some quality bolt-on's and you are good to go.

 

any other opinions or useful knowledge?

 

b16a/b and the b18c5r have different cranks but same deck heights as far as I know. Some people get the B16b engine and swap a type-r b18c5 crank in for more stroke.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chrisw85 &raquo;</TD></TR><TR><TD CLASS="quote">b16a/b and the b18c5r have different cranks but same deck heights as far as I know. Some people get the B16b engine and swap a type-r b18c5 crank in for more stroke.</TD></TR></TABLE>

Not exactly.

B16A/B17A share same block.

B16B/B18C/1/5 share same block.

A B16B is essentially a B18C-R w/ a B16A crank and different length rods in it.