Dropped the car off this morning for the leakdown test and the motor is officially BLOWN! Cylinder #1 had 22% leakdown and Cylinder #3 had 11%. We stopped there. I am making arrangements to ship the car to SGP to have it rebuilt and then the car will be sold!

I think the ringlands might have gone. Whatever it is I will have SGP fix it and get the car running like new again before it is sold. This is a great opportunity for someone looking to build a G. You could even pay for any extras you may want, like sleeves for example. I will be paying for the motor to come out anyway so you can take advantage of that and not have to pay those labor charges.

Anyone interested please email me at jguzman@carnival.com. $43K OBO.

 

Wow, this is tragic. I hope you don't have to foot the full engine rebuild cost. Good luck on getting it fixed and sold.

 

Sorry to hear this Jorge. It was a beautiful car. I was lucky enough to see it when it was at CP Race back in August.

 

That REALLY SUCKS !!!

Sorry to hear that man, you had a really nice car.

Best of luck !



Tasso-

 

how many people are running 550whp or so on a built block with no issues? Seems like there's some sort of coolant or oil problem above 500whp right? like the water pump or oil pump aren't strong enough to keep the engine cool with that much power? Think I read that somewhere as being a theory

sorry to hear about the bad news I'm going to keep my vortech under 400whp on my stock block

 

How is Sharif running 600+ then?

 

I dunno, just relaying what I've read

sharif uses race gas for that power level doesn't he? Also does he run it at 600+whp all the time or drive the car around all the time? I mean, I don't know. He could answer that better than me

 

Well I know he runs at AT LEAST 500 RWHP all day on pump gas...

 

These leakdown numbers do not mean your motor is blown.If you are getting your leakage through the oil filler then it is a problem with the rings or pistons, for sure.........but if it is coming from the intake ports out of the intake manifold or out of the exhaust ports then it is a problem with a valve.If it is coming up from the crankcase breathers on the valve cover then it is a valve seal or guide problem.Just some info for you.

 

I think most people would agree that going FI or any major mod will most likely reduce engine life. The question is how much? Speed = money, are you willing to step up and play with the big boys? if I remember correctly, the benchmark for Nissan engineers was to make the Z motor go 200k but I could be wrong on that fact.

It would be an interesting thread to survey people to see what they would accept out of the life of their motor if it was FI (10K?, 30K?, 50K, 100K?). Time will tell what percentage of FI cars will safely hit 100K. Hey, sounds like an interesting mag article for the first guy that hits the benchmark????

The rate of blown motors that are FI seems to be gong down percentage wise. At least we are beginning to find some somewhat safe limits.

 

We modify the factory oil pumps to allow for more pressure on the motors we build.We have the cranks cross-drilled and allen plugged for better oiling to the bearings which helps out quite a bit

 

I got the joy of taking a ride in Sharif's beast on sunday and he said that it was still probably pushing around 580-600 rwhp on pump gas. After that quick spin around the block I wouldn't doubt it

 

can any machine shop do this? how much would one charge for this.. i think this is a great idea.. since my problem was a rod end bearing from oil.... can you reccomend any other precaution with being over the 500hp mark? like larger radiator? ect...

thanks tim.. i should be contacting you in a month or two for a 3" exhaust btw do you guys have 3" test pipes?




ps... sorry gmann.. hopefully its not as bad as you think.. if i were you i would keep the car forever since youve put so much into it and have it be your project for life... thats what im gonna do... hopefully its just a valve.. i dont think you have that much damage going on

 

ps... how much would you charge for a modified oil pump?

 

How much of a decreace in life span is it??

 

GMan2004,

How much mileage did you VQ have before FI?
How much mileage did you put on it before she died???

 

Any machine shop building motors for the Z also "mods" the oil pump as well - it typically involves shimming the pump so there is more pressure supplied. Does not increase volume, but it works very well on motors such as this.

The quick down and dirty way to tell where the loss of compression of is to dump a bit of tranny fluid into the spark plug hole and crank the motor with the compression tester hooked up. If compression shoots up, its the rings, if it stays the same, it's in the head.

My own theory - its not a cooling issue at all - but rather, a tuning issue. If it is a problem with cracked ring lands, 9 times out of 10 it is due to tuning (especially with regards to timing)

 

I would agree that it would be tuning not the motor or parts, I think you have the emanage still right jorge? it would be interesting if you could post up the fuel and timing maps.

As for longevity I wouldn't expect low life look at the 300ZX TT, they go into the 100K+ range easily, usually the turbos give out, if it is tuned properly a forged motor like this should not have a short life span at all.

 

The block had 18K mile before SGP built it up.....5K on the built block.

 

Still have EU. For some reason I can't get my lap top to communicate with the EU.