Any thoughts on how these two motors would compare?

Autocross season is coming up QUICK and I have a new vtec build planned BUT I would like to sleeve my GSR rather than run a Non-Vtec block.

P75 head Milled .035"
Local machine shop "performance" valve job stock port

Supertech single springs
Stock retainers/Valves
Crower 403 cams
BDL cam gears
??Blox/Skunk/Ebay?? intake manifold (bought it local for $50)
PP 65mm TB
Skunk2 Header
Vtec oil/water pumps

B20B Stock JDM block (unknown milage)VS B18B block w/P30 pistons/ARP bolts (Built for a friend who backed out)

It will basically cost me next to nothing to change to the blocks over, I already have every part sitting around and the short block is already assembled.

This motor will be kept around as a back-up motor in case I sustain another mishap.

OLD B20 dyno on smaller cams/LS manifold/Edelbrock header

 

I personally say go with the B18, because its rebuild, and you know its reliablity, unlike a unkown mileage/condition B20. just my opinion though,

 

stick the 1.8 in. Its been rebuilt and has rod bolts i'd think that would be better forr autocross.

 

Its a toss up may be a neat project.

B20 Pro's
Larger bore allows better breathing
Larger displacement moves more air

B18 Pro's
Fresh build
Higher compression.

At what point does compressing the air tighter overcome the displacement?

 

I dont think that your 1.8 will have the same torque feel...Your 2.0l is a nice idea for your autocross season.

 

I say the B20. The low compression ratio (and additional displacement) will insure torque is good in the lower RPM, where you need it on a tight autocross course when powering out of corners. Just don't use a huge cam or that low rpm torque will be lost.

 

When you have the cams to release it.

 

I'm going similar build trying to do either b20 or ls all motor non vtec.

on the ls head you had mill'd?? the stock combustion chamber volumne is 45.00 for ls heads and you milld yours .035" over so what does it bring your (CCV to) looks like a gsr head which is 41.60

 

Stage 1 Complete

 

Looked like this after milling


with .035" off its roughly 40.5cc