Ok I have a ITR head lying around and I have a line on a GSR block for a really good price...... I need something in my street car for now but don't want a complete dog I know the compression drops when you do this set-up so if I shave the head 20thou what else can I do? thiner head gasket???.... if so I heard you could take a layer out of the stock one should I do that or buy a thiner one? and who makes those?
Thanks for the help guys I would like to get as high of compression as posible without taking it apart like the pistons and ****. Rob

 

I would invest the time and money now and replace the pistons. It isn't that hard to replace the pistons when the block is already seperated.

 

no doubt... the stronger rods are well worth it! and 11.5 compression is great too!

 

yup i agree

 

Yea I know but time and money is not on my side! Rob

 

don't mill the head and run a thinner HG- you will end up with piston to valve issues- as me how I know

 

how do you know?

 

B16 stock bottom end, milled head .020, Mugen HG, JUN III cams= blown motor at 3200 rpm @ 2:30am in the middle of no where.... not a good time.

 

if you milled the head you have to correct(advance) the cam timing back by using the adjustable cam gears, that would be another investment. ignition timing would be a problem too... thinner head gasket may be a good way.

btw, also consider is your cooling system needed to be upgrade? higher CP motors generate more heat.

 

actually, if you install the cams correctly, you won't need to adjust them via the gears... common mis-conception.

 

Head gasket would be the cheapest way to gain compression. just make sure that if you have a big cam ,your clearance is ok.

 

I'm going to run CTR cams and already have ajustable cam gears..... you can ajust the cams to compensate for the milling of the head....... So what would my compression be then 20thy shave and a Mugen head gasket or just shave the head what's the compression???? TIA Rob

 

well .020 mill and the Mugen gasket (which equates to .030 mill) would be about a .050 mill- realistically, you'd have to clay the motor to figure out what is going to work best for you

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sircrxracer &raquo;</TD></TR><TR><TD CLASS="quote">Ok I have a ITR head lying around and I have a line on a GSR block for a really good price...... I need something in my street car for now but don't want a complete dog I know the compression drops when you do this set-up so if I shave the head 20thou what else can I do? thiner head gasket???.... if so I heard you could take a layer out of the stock one should I do that or buy a thiner one? and who makes those?
Thanks for the help guys I would like to get as high of compression as posible without taking it apart like the pistons and ****. Rob</TD></TR></TABLE>

If you run a 2 layer headgaset you should get back to the GSR's 10:1 compression. With a mild cam this should be OK. I'm not sure of what kind of power you will be able to put down.

Does anyone have any numbers from this type of setup? would 180-190 hp be possible at 10:1 compression and something like a Skunk stage 1 or Toda A?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by advanracing62 &raquo;</TD></TR><TR><TD CLASS="quote">actually, if you install the cams correctly, you won't need to adjust them via the gears... common mis-conception.</TD></TR></TABLE>

The guy posting above is saying htat if you mill the head it will retard timing ive heard and believe that this is true.

 

Well, I had my head milled .020 and ran the Mugen head gasket on a B18C. I have Toda b's and toda Cam gears. Car was dynoed/tuned for approx. 3.5 hours. Drove home from NY (2 hrs.), drove 1 hour next day and boom. 8 intake and 3 exhaust bent like an S. I was told if I wasn't running all Ferrea valvetrain I would have no motor from valves breaking into pieces. I now am running stock headgasket with my set up. My advice is to just run stock headgasket, not worth the hassle of blowin it up.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by advanracing62 &raquo;</TD></TR><TR><TD CLASS="quote">actually, if you install the cams correctly, you won't need to adjust them via the gears... common mis-conception.</TD></TR></TABLE>

milling head doesn't really reatard the timing, but it does change the relative position of piston and valve. it decreases the clearance between the valve face and piston. for example, in compression stroke, the intake valve is about to close after BTDC, at this time the piston is raising so is the intake valve, you know the bigger duration cam will close the valve slowly, if there is not much clearance between the piston and valve then they might just hit each other.... it happens more commonly in aftermarket cams applications.

 

I was under the impression that when the head is milled or a thinner headgasket is used, there is more slack in the timming belt. When tensioning it down, the slack will cause the cams to be pulled backwards slightly (retarding them).

 

well it looks as I'm going to cheap out and mill the head 20th and that's it....... what's my compression going to be? Rob

 

I think the best way to bump the compression with your set up would be to weld the combustion chamber square (like the gsr head) mill it .060 with a mugen h/g. Aim for about 40cc in the chamber. This is the easyest and cheapest way. if your planning on running big cams you might want to clay test that bitch.....lol