Jump to content
SAU Community

Recommended Posts

Surely there is a limit as too the maximum amount that the rb20det head can be skimmed.there must be a way to measure maybe a reference point on the top of the head to the block mating surface.i don't want to buy another unskimmed head as a reference, as that will tell me nothing other than mine is thinner.i just want to make sure im not gonna increase my compression ratio on my stock bottom end and damage anything.

Link to comment
https://www.sau.com.au/forums/topic/429062-rb20det-head/#findComment-6939009
Share on other sites

At the end of the day, someone will have had to really hack into the thing for it to be considered 'too thin' to use. Not too many machinists would do that.

Rb20det comes from the factory with quite a low compression ratio as it is. A couple points more static CR is only a good thing.

When you put it back together, just be sure to get it on a dyno.

Cheers

J.

Link to comment
https://www.sau.com.au/forums/topic/429062-rb20det-head/#findComment-6939072
Share on other sites

At the end of the day, someone will have had to really hack into the thing for it to be considered 'too thin' to use. Not too many machinists would do that.

Rb20det comes from the factory with quite a low compression ratio as it is. A couple points more static CR is only a good thing.

When you put it back together, just be sure to get it on a dyno.

This ^ at 8:5 to 1 an increase in CR wont harm the motor

Cheers

J.

Link to comment
https://www.sau.com.au/forums/topic/429062-rb20det-head/#findComment-6941335
Share on other sites

Piggaz advice is 100% valid. Put the valves in with some grease around the seats to make sure they seal. Get the clear part of a CD case and drill a 5mm hole in the middle. Slap that on the head face with a smear of grease to seal it. Set the head so it's nice and level. Use a burette or even a syringe to measure how much water you put in through the hole. Even with rough set up and equipment you'll be able to find out to within a fraction of a CC what the volume is. Job done.

Link to comment
https://www.sau.com.au/forums/topic/429062-rb20det-head/#findComment-6941339
Share on other sites

  • 3 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Thought I would get some advice from others on this situation.    Relevant info: R33 GTS25t Link G4x ECU Walbro 255LPH w/ OEM FP Relay (No relay mod) Scenario: I accidentally messed up my old AVS S5 (rev.1) at the start of the year and the cars been immobilised. Also the siren BBU has completely failed; so I decided to upgrade it.  I got a newer AVS S5 (rev.2?) installed on Friday. The guy removed the old one and its immobilisers. Tried to start it; the car cranks but doesnt start.  The new one was installed and all the alarm functions seem to be working as they should; still wouldn't start Went to bed; got up on Friday morning and decided to have a look into the no start problem. Found the car completely dead.  Charged the battery; plugged it back in and found the brake lights were stuck on.  Unplugging the brake pedal switch the lights turn off. Plug it back in and theyre stuck on again. I tested the switch (continuity test and resistance); all looks good (0-1kohm).  On talking to AVS; found its because of the rubber stopper on the brake pedal; sure enough the middle of it is missing so have ordered a new one. One of those wear items; which was confusing what was going on However when I try unplugging the STOP Light fuses (under the dash and under the hood) the brake light still stays on. Should those fuses not cut the brake light circuit?  I then checked the ECU; FP Speed Error.  Testing the pump again; I can hear the relay clicking every time I switch it to ON. I unplugged the pump and put the multimeter across the plug. No continuity; im seeing 0.6V (ECU signal?) and when it switches the relay I think its like 20mA or 200mA). Not seeing 12.4V / 7-9A. As far as I know; the Fuel Pump was wired through one of the immobiliser relays on the old alarm.  He pulled some thick gauged harness out with the old alarm wiring; which looks to me like it was to bridge connections into the immobilisers? Before it got immobilised it was running just fine.  Im at a loss to why the FP is getting no voltage; I thought maybe the FP was faulty (even though I havent even done 50km on the new pump) but no voltage at the harness plug.  Questions: Could it be he didnt reconnect the fuel pump when testing it after the old alarm removal (before installing the new alarm)?  Is this a case of bridging to the brake lights instead of the fuel pump circuit? It's a bit beyond me as I dont do a lot with electrical; so have tried my best to diagnose what I think seems to make sense.  Seeking advice if theres for sure an issue with the alarm install to get him back here; or if I do infact, need an auto electrician to diagnose it. 
    • Then, shorten them by 1cm, drop the car back down and have a visual look (or even better, use a spirit level across the wheel to see if you have less camber than before. You still want something like 1.5 for road use. Alternatively, if you have adjustable rear ride height (I assume you do if you have extreme camber wear), raise the suspension back to standard height until you can get it all aligned properly. Finally, keep in mind that wear on the inside of the tyre can be for incorrect toe, not just camber
    • I know I have to get a wheel alignment but until then I just need to bring the rear tyres in a bit they're wearing to the belt on the inside and brand new on the outside edge. I did shorten the arms a bit but got it wrong now after a few klms the Slip and VDC lights come on. I'd just like to get it to a point where I can drive for another week or two before getting an alignment. I've had to pay a lot of other stuff recently so doing it myself is my only option 
    • You just need a wheel alignment after, so just set them to the same as current and drive to the shop. As there are 2 upper links it may also be worth adding adjustable upper front links at the same time; these reduce bump steer when you move the camber (note that setting those correctly takes a lot longer as you have to recheck the camber at each length of the toe arm, through a range of movement, so you could just ignore that unless the handling becomes unpredictable)
    • I got adjustable after market rear camber arm to replace the stock one's because got sick of having to buy new rear tyres every few months. Can anyone please let me know what the best adjustment length would be. I don't have the old ones anymore to get measurements. I'm guessing the stock measurement minus a few mm would do it. Please any help on replacing them would be fantastic I've watched the YouTube clips but no-one talks about how long to set the camber arm to.
×
×
  • Create New...