Which 3500 should I choose to turbo.

[scrabblegod]

Tomorrow, I am going to pick up the 3500 to use in my turbo Fiero project. Should I grab the 06 G6 3500 or the later 3500 VVT. I am not so much worried about the VVT, but am wondering if one engine is preferable to the other to turbocharge.

Thanks,
Gene

[Jonpro03]

The VVT will be better.

How do you plan to run the engine? Which engine computer are you going to use.

[scrabblegod]

I am not decided on the 7730 or megasquirt. Not even decided on the turbo I am using yet. I have several turbos, but none that really seem to fit the bill. I just want to get the engine so i can get it mounted on a spare cradle.
I considered the 3.9, but want to stay with the 3.5 for the easy flywheel/clutch comb.
I guess i am wondering if the different bore/stroke of the 3.5 vvt is enough benefit to deal with the vvt hassle.

Gene

[CNCguy]

There are Pros and Cons to both engines.

The LX9 (non VVT 3500) has been proven to be a reliable performer, fits with minimal work and uses a standard cam but only has oil squirters on cylinders 5 & 6.

The LZ4 (VVT 3500) has larger ports, runners & valves and squirters on every cylinder. The drawbacks are that you will be stuck with locking the VVT cam (can be reground) in the proper location. The alternative is to eliminate the VVT setup which requires using cam bearing spacers or having the journals welded and reground on a GEN3 cam. The other obstacle is the coolant return system. The returned coolant exits the front of the heads via a large casting that is also the P/S and ALT bracket. This requires using the late model alternator and rearranging your radiator and heater hoses.

The LZ9 (3900) has the same bellhousing pattern and flywheel mounting setup as all of the earlier 60V6 engines. Where people run into problems is with the clutch/flywheel setup for the 6 speed transmission. They came with the thick and heavy dual mass flywheel.

Do a search for JosephUpson. He has many posts with pictures both here and on the Fiero forum about his turbo 3900 Fiero swap. The LZ4 and LZ9 would be identical swaps since they use the same block, heads, lower intakes, VVT and coolant system.

[scrabblegod]

Well after looking at the 3.5 and the 3.5VVT, I see what you were talking about concerning the water manifold. I also looked at a 3.4 from an 07 Torrent.
He did not have the 3.9 there, so I grabbed the plain 3.5 out of an 05 G6 with 28k miles.
He offered to get me a 3.9 from one of his other yards, but I decided I did not trust him and just got what I could.
The back story is, I spent a the better part of a Saturday a month ago pulling cat5 for him and configuring his wired and wireless network. It was only a couple hundred bucks, but the check bounced. I told him I would take the 60 degree of my choice and call it a done deal. I am comfortable with the motor I got as I actually saw the car it came out of when I cut the pillar section out of it to fix my wife's G6 3 years ago. It has been on the warehouse shelf since.

Thanks for the information, and I hope I can get some more guidance when I try to decide on the turbo/turbos to use.

Gene

[CNCguy]

Although I have a converted 3900, I think you made the right choice. It will be much easier, you will spend less money and can still get great results. A couple hundred bucks is a great price as well. Good luck.