Thread: SR20VE compression test numbers...

^ That would be good! Report back sir!

I did some reading and it seems that SR16VE cams raise the compression a bit and N1 cams lower the compression a bit. Smaller low lobes make a difference I guess?!

oh you know what, the sr20ve low lobes and n1 low lobes are nearly identical, very subtle change iirc. so i doubt that would change much from stock cams.. 16's might though..

Edit: the n1's Exhaust cam has 1.35mm more lift on the low lobe, same duration. The intake cam low lobe is identical between n1's an stock sr20ve cams, its the exhaust cam low lobe thats slightly different.

Ya, I hear ya. I'm going to try and find the posts I read earlier just for shits and giggles. I think the comparison might have been just between the 16VE's and the N1's.

Yeah the reason the sr16 cams bump compression is the less duration on the intake cam. The longer duration cam you go with the less compression your likely to see.

In reality, the stock cam and n1's should compression test the same.

^ Makes sense. I'm just happy that my numbers are 200 across the board. I'm not loosing coolant or oil so I guess I shouln't worry too much. It is kind of weird that they all would have dropped 20 PSI equally. I think another test is in order just to be sure. My poor starter!

I like to do my tests with all the plugs out at the same time. Makes it easier on the starter and get a little bet quicker cranking speed which will make a difference.

Yeah 200 psi and the fact they are all even is another good sign. You should be just fine.

i do 1 plug at a time an put it back in before moving to the next.

when you say 5 cranks , is it 5 full turns?

5 Compression cycles on the cylinder

I got 225 on all 4 with 20V low lobes on my 11.5:1 87mm motor. Makes sense with the 20V intake having the longest duration bringing it down from what I might have expected.