3.9L LZ9 engine internal upgrade & performance?

[SappySE107]

Yes they designed some rockers for the 3900 as well. They are close but not compatible.

[IsaacHayes]

Interesting that your block was not painted on that one side, its all rusty!

[mrtohil]

Yeah, that'll be corrected after the oven & peening. After that I'm painting it to make it centerfold worthy .

[Nightingale]

My manual confirms a stock deck height of 8.818. The wierd thing is this manual also says rod length is 5.9", but after talking with pauter rods who measured my stocker they gave me a measurement of 5.827 center to center. Hopefully the rest of the specs are all good to go by. No word on wall thickness yet. If anyone needs any other specs listed I will be happy to share.

[bszopi]

I'm willing to bet your manual will list the exact same specs we already have on the site (see post #12 for link).

[Joseph Upson]

My manual confirms a stock deck height of 8.818. The wierd thing is this manual also says rod length is 5.9", but after talking with pauter rods who measured my stocker they gave me a measurement of 5.827 center to center. Hopefully the rest of the specs are all good to go by. No word on wall thickness yet. If anyone needs any other specs listed I will be happy to share.

How about posting the weights of the piston and rod along with some info regarding the VVT function.

[Nightingale]

I will page through tomorrow and try to get some scans, but ya I did read the specs page. I was weary about trusting the specs page as I didn't know the source. Either way the Helms manual is extremely helpful. Also I don't believe it lists weights just clearences and tolerances, dissassembly/assembly instructions, diagnostics, etc. It includes everything for the g6. I was a little surprised to find 3 telephone book sized manuals in the box weighing around 15lbs lol. I knew there'd be a lot of info just not that much heh.

[IsaacHayes]

Yeah thank the electronics for all that extra crap! LOL

[mrtohil]

Hey Nightingale, what the PN for the paper manual. And how much was it if I may ask? Is there a CD/DVD version available? I would like to get the manual myself and start reading up on it. I need to figure out how I'm gonna run this motor after I'm done with it.

[mrtohil]

That is a good question about the weights though. If no one has the specs and/or a scale, I'll see if I can obtain a scale and post what I find since I have everything apart already.

[Joseph Upson]

I knew the weights wouldn't be in the manual, I thought you had parts at the machine shop that can be weighed.

The Helms manuals aren't cheap, and probably cost ~$ 135, years ago they went fromt about $45 to more than double that I discovered on attempting to order a Fiero manual a few months after having ordered one for my camaro.

Electronics wise it should have some valuable info on the VVT module and that would be good to have.

You can search the HELMS company on line for the manuals, I'm sure you won't be interested in the $400 CD sets.

[mrtohil]

I measured one of my rods today. It ended up being 5.925in, which is pretty close to the 5.9in advertised in the spec sheet.
I don't think the school has a scale intended for this. I'll find out. If it ends up too much of a hassle I might as well get a small electronic one of my own.
Well, this weekend I'll have to dedicate on knocking on everyone's door who makes rods and find out how much for some forged rods. Let the Benjamins start flying out my wallet!

[Nightingale]

I would just shave the crank rod journals and use sbc rods. All said and done it'd be cheaper then custom. Pauter quoted me around 1200 for a set of rods, but they are pretty much indestructable. I am probably gonna go with eagle 3d rods with l19 rod bolt upgrade. It will give me a slight bump in displacement (like 3.9l to 4.0L lol), but I still want to keep the rod/stroke ratio good and keep up revability versus just going for max displacement. I know I can pick up more stroke from going to the small journal sbc rod vs the big journal rod, but not sure how much it'd affect the integrity of the crank if at all.

[Joseph Upson]

I measured one of my rods today. It ended up being 5.925in, which is pretty close to the 5.9in advertised in the spec sheet.
I don't think the school has a scale intended for this. I'll find out. If it ends up too much of a hassle I might as well get a small electronic one of my own.
Well, this weekend I'll have to dedicate on knocking on everyone's door who makes rods and find out how much for some forged rods. Let the Benjamins start flying out my wallet!

Check your rod length again to be extra sure because so far at least two other members have measured 5.827" rods including myself instead of 5.9", unless a change was made somewhere I can't see there being two different rods under the circumstances.

A small block chevy rod is the best route to take except in an extreme build. That is what was done with the old 2.8L for increased strength. For the cost of custom rods you can buy a set of forged chevy rods good to at least 600 hp or more and have the crank welded if necessary and offset ground. The pistons have offset pins if I recall correctly to help reduce side thrust loads so going with a 5.7" rod shouldn't cost you any sacrifice especially with todays metallurgy and design. The LS1 pistons also have offset pins which is another plus for them being used in the 3900.

[mrtohil]

I measured them again. I actually did two of them. We came up again with the same number of it being slightly longer than 5.9in. Dunno what to tell you.