Thread: Safe max rev on SRXXVE cams

So sorry to jump in here. I have stock springs, and N1's. I was also curious as to what you feel a safe range to rev to is.

I spin in first so when I shift out I instantly bog down quite a bit in second. I feel hitting the limiter would help allot with the car getting up to speed in first gear.

I was thinking of setting my limiter to 7500 so I won't have to worry as much about limiter.

I am a conservative driver and don't usually redline the car, but getting out of the hole is pretty weak right now with that 1st to second shift.

Any advice would be great.

Dudeman

Do you have cam gears,pulleys, and a light weight flywheel? Those three should help you out alot if you don't have them already.

What are signs of valves floating? What do you hear?

Peace

Breaking...

Normally guys hear the motor go flat when they start to float. Other guys don't notice until the valve hits the piston.

it's a very monotone metallic sound it's hard to describe but very easy to point out when you hear it.

You can also tell on a dyno because your torque line looks like you feel off a cliff

So the safest rpm for stock sr16 cams is about 8500rpm. I think I will just use the VET and 20ve cams with some valve springs and rev to 8500rpm or so. I wonder which one will be best? Hmmmm.

Is anyone scared of pulling the valves through the seat on these aftermarket valve springs. I have had some bad experiences using high rate valve springs...

Its easy to hear on a B series motor on the dyno when they rev a stock Type R motor to 10k... once. at about 9300rpm or so the engine note flattens off like someone is lifting off the throttle, then the engine makes noise and dies... its great



SR16 cams can probobly go to 9000rpm maaaybe but i dont want to be the one to find out.

The problem with the valves pulling through the seat is usually on CHEAP aftermarket valves that are weak and or the valve throat was opened up too much. Usually its the cheap material, like chinease $110 set of valves for all 16. These are not real Inconnel or stainless valves that are strong and have high heat fatigue.

Just get some BC springs, throw em in, and you should be good to 9k no problem on the sr20ve or VET cams.

^^^Snickers, have you back to back tested your turbo grind cam against the sr20ve cam..im just curious as to how much it would be worth power/torque wise on my setup over 20ve cams?

I am not sure, There is about 2mm more lift and another 20 deg duration @.050" lift and the duration at .004" has been reduced as well. I'm quite confident these will make more power.

I wont be making anymore of these until Cam cores are available.

So there are 2 types of SR20VE spring? Ha ha... this kind of explains the different results we were having that resulted in those arguments about standard vs uprated springs - We were all correct!

Gold.

I now have Kelford's uprated springs in my engine but my previous build had Nissan springs & hit its 9,250rpm limiter on Franklin Stage 4s many times. When we pulled the head off there were no signs of any problems & it had done over 50,000km.

The gentleman who built my engine builds most of the competition VEs in NZ and always uses standard Nissan springs in his race engines as he reckons they are just about perfect... He grumbled about my new head having uprated ones!

I'm not saying anybody else is wrong or right, just putting out there what has been working for us for several years. Maybe we get different results 'cause our country is upside down :P