Few months back I started on building a high compression all motor B20. I knife edged my crank, have Crower rods and custom 11:5:1 84.5 JE's. However recently I decided to go CRVTEC with a GSR head. The releifs on the pistons can either accomodate either GSR head or LS. The problem is if I use the GSR head my cr will be above 12, and I have heard nightmare stories of people with high compression and 91 octane pump gas detonating or riding around with major pinging. With the LS head I will be at 11:5:1, but with the GSR head I will be over 12, would the B16 head be a better choice? Can I use a thicker headgasket with the GSR head? How can I put on a VTEC head and not worry about detonating?

 

Thicker gasket sounds like the best and easiest idea to go with. But, how much thicker can you go?? And how much will that lower your comp??

 

How do you guys running near 12 cr keep from detonating on pump gas?

 

The ticker head gasket will help.. and retard your timing shuold help too.

 

ok ignition timing you can't advace it to high stock the highest.
lots of cooling, helps combustion chamber temps wich helps detonation.
and richin fuel ratio helps cool the combustion temps also
here is my setup its a non detonating 12.1 compression.
MY SET UP> RAINFOREST
Block
brand new bearings,seals, and gaskets, flexlite magnetic drain plug.
endyn/eagle rods
endyn 12:3 commprssion they are 12:1 but i tru milled the head and decked the block. unorthadox racing pully
p30 oil and water pump
arp head studs
arp 2000 rod bolts

HEAD b17a
2001 type r cams
portflow ti retainers
type r inner valve springs/b16a inners on exhaust side.
type r intake valves/5 angle valve job
spoon cam gears
ported throttle body
ported sligyly by myself


fuel
rc 270cc injectors
b&m
bosch in take fuel pump
feilds sfc/vtec

spark
ngk wires
ngk spark plugs
msd cap
msd 6a
msd blaster3

cooling
gsr radiator
spoon thermostat adj fan swich
spoon radiator cap

tranny
y1 w/lsd
centerforce dual friction.

bolt on's
hks intake
jdm 4-1 w godspeed test pipe
itr intake manifold



[Modified by rainforest, 2:37 AM 1/23/2002]

 

Well I think I found a 98 GSR head, some local guy has one complete minus distrubutor for $450, so I am meeting up with him tomorrow, how can I tell if the head is good and not blown?

 

look for damage to the combustion chamber, take the valve cover off look for all valvetrain componets lma's, rocker arms, and valves. Look for any bent valves or chips anywher like on the retainers. make sure it has every bolt. just go over it with a fine tooth comb.

 

the B16 head is not necessarily a better choice over the GSR but it will take that compression down approx .3 points. like the other guys said too, ECUs and retarding the timing is the key to drivin on pump gas.

 

Back from the dead baby.....

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Halo &raquo;</TD></TR><TR><TD CLASS="quote">Few months back I started on building a high compression all motor B20. I knife edged my crank, have Crower rods and custom 11:5:1 84.5 JE's.

However recently I decided to go CRVTEC with a GSR head. The releifs on the pistons can either accomodate either GSR head or LS.</TD></TR></TABLE>

Why can't the reliefs handle the B16 head?


Modified by BlueTeg at 6:28 PM 10/30/2003

 

well dont use 92 gas then, from what i undertand 92 is the lowest kind in the US? cuz in canada we have as low as 87 octane , if your gonna build a high performance car, start feeding it 98 + octane no pain, no gain.

 

if you use a gsr head and your comp. is 11:5:1 now, it will be 11:7:1.but if you use b16 you will drop 2 tenths because of the larger combustion chamber.you will be o.k. if you use 93 or 92 octane.

 

So far the biggest gasket you can get is a 1 mm unless you split an OEM and stack part of another gasket inside (risky), this will only drop your c/r down a couple tenths.

I have heard a lot of good things about water injection to stop detonation. It stops the need to run rich or high octane. Check http://www.aquamist.co.uk/

 

hey man, you can send the head off to alainz and they can reshape the combustion chamber to lower the compression and assist in flow.

I think you can do it with the gsr head, but there are a ton of different options.

You should move to the dirty south with me, 12.5:1 and 93 octane, runs like a champ on chipped p28, and THAT'S IT!