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Comcal76 wrote:

vlad01 wrote:Looks good. I'm going to get my new daily VP auto built too, so it doesn't shit the bed before 200k like they all do.

Did you replace your valve springs when you did the rockers or are they still stock?

You should rebuild it yourself they are easy to do, the valve springs are 130lbs they were done when I had the motor built.

for 1700 bucks I won't bother myself. I spent nearly 4K on my manual doing it myself so it was worth it as the car was also a special restro project and the parts were very expensive and presentation was also important for that one.

I am pretty much farming out everything remaining to someone else on my daily as I don't have a hoist or room in my shed to do what I need nor do I have motivation for a daily driver unless it's simple things that don't disable the car for weeks.


Did the new springs help with it being able to rev (not die in the ass) above 4K? I am finding that current shitbox daily isn't performing as it should and I have ruled out everything else. Seems to struggle in all gears except 1st above 4K and is no quicker than my new stock auto low K daily VP despite having pacemakes, good intake and proper tune and manual. It's significantly slower than my VR with the same setup and tune.

I am starting to think springs as it's 91 model and done nearly 350K and been trashed all it's life. I am replacing the springs and lifters on the other new daily as a preventative exercise and given stock springs are cheap I might do the shitbox too?

Can't recall who, maybe Delowizzid? had engines do the same? I am trying to work out which ones to get from Crow. 4936-12 or 6038-12 One is meant to be replacement standard and the other standard one has a damper. Crow don't list the specs for either so I am not sure and their helpfulness is next to none.

vlad01 wrote:

Comcal76 wrote:

vlad01 wrote:Looks good. I'm going to get my new daily VP auto built too, so it doesn't shit the bed before 200k like they all do.

Did you replace your valve springs when you did the rockers or are they still stock?

You should rebuild it yourself they are easy to do, the valve springs are 130lbs they were done when I had the motor built.

for 1700 bucks I won't bother myself. I spent nearly 4K on my manual doing it myself so it was worth it as the car was also a special restro project and the parts were very expensive and presentation was also important for that one.

I am pretty much farming out everything remaining to someone else on my daily as I don't have a hoist or room in my shed to do what I need nor do I have motivation for a daily driver unless it's simple things that don't disable the car for weeks.


Did the new springs help with it being able to rev (not die in the ass) above 4K? I am finding that current shitbox daily isn't performing as it should and I have ruled out everything else. Seems to struggle in all gears except 1st above 4K and is no quicker than my new stock auto low K daily VP despite having pacemakes, good intake and proper tune and manual. It's significantly slower than my VR with the same setup and tune.

I am starting to think springs as it's 91 model and done nearly 350K and been trashed all it's life. I am replacing the springs and lifters on the other new daily as a preventative exercise and given stock springs are cheap I might do the shitbox too?

Can't recall who, maybe Delowizzid? had engines do the same? I am trying to work out which ones to get from Crow. 4936-12 or 6038-12 One is meant to be replacement standard and the other standard one has a damper. Crow don't list the specs for either so I am not sure and their helpfulness is next to none.

The engine I had built I never ran it before I had it rebuilt so I don't know if the springs make a difference.

I had a look through all my logs and not once have I been over 4k, next time I have it out I'll rev it 4500rpm and see what happens.

I remember my old engine that had 280k on it seemed to die in the ass around 4k, when I pulled it apart to keep the heads I found 3 bent pushrod.

I always pretty much rev them out to the limiter as I don't feel any noticeable drop off at all even to the redline. This allows the best acceleration as it allows the next gear to land in a higher part of the power band.


Interesting you mention the bent pushrods. I have only ever personally seen it on Holden 5Ls but when I was looking at buying a VN locally the young bloke said it's normal for the V6 to bend pushrods and he changed his at least a dozen times. I said there must be something wrong as I hadn't heard or seen anyone else do that.

Perhaps it might be a sign of weak springs or a sticking valve or something? But for sure when I replace the springs I will keep an eye out for any bad pushrods, though this engine's lifters are one of the rare engines where they don't tick or rattle so I doubt there will be much problems other than weak springs.

I have read many of the GN guys in the states say new springs make a huge difference in their ability to keep making power higher up without dying in the ass at 4K.


I know there is a problem when 3rd gear struggles to break 150 but 4th quite happily gets to 180 and out accelerates 3rd in the 150+ range. 3rd normally gets to 170-175 at quite a decent pace.

Took the car for a drive top rpm was 4280rpm then started surging and bucking and would not pick up anymore speed.

Edit
This was in third gear at 152 kph on a private road.

Sounds like spark gaps are too big.