Thread: G Spec VVL Crank Pully + High HP + High Revs = Fail...

Doctor G, I was trying to keep this thread on topic, so I didn't answer that one. That is a discussion for another thread. You're basically asking "what are the benefits of a better harmonic balancer than the stock one?" and that's not going to take a simple answer, although I'll try.

It should dampen crank harmonics better and/or over a larger rpm range than the factory damper. They are commonly used for high rev applications (9k+).

yeah i had this issue but you can tell from the pics he is using the actual ve oil pump drive/spacer. Unfortunately for me it cost me some compression loss due to 3 startups with 0 oil pressure before i realized that the damage was done to the pump before i found out about that spacer. Anyways but i think my compression is slowly coming back as i beat on the motor. It runs better and better the more i beat on it.

Neways payu, sorry to hear about the mishap. But the plain fact is our oil pumps and oil pumps driven off the crank like ours are very very fragile. They do not like 9k+ rpms. They tend to crack and break like that especialy if you missed a shift and went well over 9k. More than likely its not the pulley that caused that pump to crack but the gears inside the pump siezing and then snapping due to just the high revs. Im using the vvl gspec pulley but i only rev to 8k. So far no problems at all. I get great oil pressure throughout the rpm band but again i dont feel comfortable reving our oil pumps any more than 8k anyways. Im sure i still hold power to probably 9 but i rev limited it to 8k. Its still fast enough as it is. Higher you go the more chances you have for something to fail.

I can almost bet you its not the pulleys fault. Maybe an ati dampener would have helped but i bet it would have still broke. Thats why motors that really rev high use an external driven oil pump and dry sump. Thats the only way to go in my book if you want to go to 9K+ especially with big horsepower.

Dont worry for the next one you will see that I will keep the Factory Pulley and I will rev to 9000 like I always like to do without problems jejejeje

THAT A BOY!!!

So it is this spacer in the kit that you guys are havving problems with ???
Front Cover/Oil Pump KIT (VVL), Front cover and oil pump from the JDM VVL motor. Will fit SR20DE wit

I have the one above , and if it really problematic , I might want to change it

or this one ....
http://www.gspec.com/p-5988-oil-pump-drive-pulley-spacer-sr20.aspx

Thanks for the answer, although I don't think the question was off topic at all. This thread is about engine failure, assumed to be from an aftermarket pulley and it's lack of damping, so the question very much fits in imo.
I think perhaps on a BIG BUILD like mazworx or something that ati pulley will be necessary then, but I don't see it being required for the average builds.

As for the stock pulley, and VVL oil pump not being able to handle 8k+ rpm, I thought the N1 16ve had a 8300 or 8600 rpm limit from the factory? I don't see the oil pump being the weak link here. Nissan won't push it to it's limit on a stock setup, so I'm sure it can handle 9k rpm now and then. It seems to be an isolated incident at the moment.

I'm really sorry for your failure Payu.

All SR16VE including N1 have 8000rpm stock limiter.

My sr16ve.n1 build on 1997 has 9200 limiter for more than 2 years using stock tuned ecu.
Engine is untouched inside and my oil pressure is not great above 90C/194F degrees.
I was using for some time underdrive pulley but it was causing lots of vibrations on high rpms and it got in my nerves every morning the belt was noisy. Dyno run back to back on stock pulley showed no gain for me.
N1 water pump pulley didn't work either and it's not needed for 16ve.
I returned back to stock pulley. Belt noises stopped, vibrations were less.
I've revved my engine quite a few times on 10000rpm. Using 2nd and 3rd gear on highway and using 4th gear on the dyno. I had no issues beside some floating noise above 9500.

N1 crank pulley weight
4.59lb
SR16/20VE crank pulley weight
2.54lb

and a small travel back to time for some of you.

^I want to know this as well.

Nissan crazy, I can see why there's a lot of confusion over this. I didn't know Greg sold two different "spacers". The second one you linked to is the one with the problem. If you look at it, it is a perfect circle with a key way cut out. From now on they will come with two notches cut out of them to make them match the shape of the oil pump drive.

Anything over 8500-9000 on a regular basis should use a ati damper in my opinion .My friend has one in his 200sx revving to 11k rpm’s with a VE knock on wood still,but even with the best performance parts a motor is still subjected to failure when under alot of load