Questions about LS4s and Pontiac G6s (Page 3/3)
ericjon262 MAY 06, 02:25 PM

quote
Originally posted by thesameguy:

In my limited OBDII experience, the refs don't have any specialized hardware. They will hook it up to a pretty generic OBDII scanner to look for smog readiness but I don't think they will investigate beyond that. They definitely don't have anything like a TechII or HP Tuners or anything like that. It's not anything more than a regular smog shop would have.

The same goes for looking for part numbers, etc., because they just don't have the references to figure out compatibility - any given part could have dozens of part numbers and they're not going to figure out whether it *actually* belongs or not. If it's made by GM and looks to be in the right spot, that's about all they care about. They will check for the presence of specific smog equipment (PCV, EGR, etc.) but they typically don't test for functionality. They don't have the equipment or procedures to do it. Sometimes they get intense about placement ("PCV valve is in the wrong place") but sometimes they don't. Typically, if it looks like it is performing the intended function they tend to ok a little fudging dimensionally. Typically. It's all a judgment game. The thing I am most worried about with an LSx swap is actually the catalytic converter. I'm honestly not sure how to get that part installed and placed satisfactorily.

The LS2 tip is excellent - that makes a world of sense. an LS2+manual that just happens to have a weird intake manifold and an unusually placed alternator. That's the ticket.

WRT the 3.9, I've actually been surprised by how available they are. There is a G6 GTP with a manual in Stockton or something for five grand, the third I've seen this year. With an automatic it would get substantially more, but I think the market for manual transmissions in this class of car is really pathetic.

http://modesto.craigslist.org/ctd/4999390632.html

High miles, but they are sturdy engines. Worst case it needs a rebuild, but five grand nets everything needed to do the swap except mountains of time and talent. I keep thinking about seeing if they'll take four for it and just having it around for when I decide to do the work.




I like the V6, my next will either be a LZ4 or LZ9. I'll probably stick with the F23 though.
thesameguy MAY 06, 03:27 PM
Sounds crazy, but yeah, I like the V6 too. The Fiero does not need 300hp to be plenty of fun and I'm in favor of the improved fuel economy and hopefully less maintenance. Plus, there is some fun sticking with a pushrod V6.

I just know I want more than the current 3.4pr has to offer, I don't want the complexity of an LQ, and there are too many pitfalls implementing a forced four cylinder. I was originally very excited about an LSJ, but I don't want to hack up the body so it's out. A high value V6 is just such a solid swap all around it really does seem like the right answer. The fact that exactly what I want - a 3.9 and a 6-speed - exists together in a car I can just buy and strip is icing on the cake.

I decided to put my old Suburban and Falcon up for sale... having a sudden influx of cash will hopefully get this show on the road.
thesameguy MAY 20, 11:20 PM
Been doing a little research and just want to clear what I think with the brain trust...

Sometime this year I'm going to buy one of those G6s, I might settle for a 3.5l but I'm really aiming for a 3.9l. Given that I do that, I can use HP Tuners to strip out unneeded module communication from the factory ECM and thus keep functional VVT. What's on the table is either adapting a DBW pedal or tuning for a 3400 throttle body and .... ? Obviously we're talking about a trivial amount of work, but this largely encapsulates all the black box software stuff, yeah?

I already sold the Suburban, so what I think I'm going to do is aim to sell my XJR sometime this summer and use the G6 as my "air conditioning car" until the weather cools down. Then dismantle it.

(Yes, I maintain exactly one car with working AC for the 10 days every summer that I just can't handle the heat.)

[This message has been edited by thesameguy (edited 05-20-2015).]

ericjon262 MAY 22, 12:33 AM
best to stick with the DBW TB for the 3500 or 3900 if you want to keep VVT, if you don't, go with an LS1 or N* TB, a 3400 TB would choke it down.

------------------
"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."

"The day I tried to live, I stole a thousand beggars' change and gave it to the rich."
http://www.fiero.nl/forum/Forum2/HTML/119122.html

dobey MAY 22, 09:50 AM

quote
Originally posted by thesameguy:
What's on the table is either adapting a DBW pedal or tuning for a 3400 throttle body and .... ?



There's really no good reason to not use the DBW throttle. If you're worried about throttle response (which can sometimes be annoying in stock configuration), you should tweak the Torque Management tables.
masospaghetti MAY 22, 10:01 AM
Personally I always have liked the LZ4/LZ9 motors, they are way smoother than the earlier V6's like the 3400 or LX9 - they feel and sound like a modern multi-valve V6. Plus, you could get that sweet variable intake with the LZ9, I assume it would bolt up to the LZ4. It also seems like these engines are superbly reliable.
thesameguy MAY 22, 04:11 PM
Good to know on the DBW. I don't much care for the feel of modern GM pedals compared to the old metal stuff, but ultimately if it's easier to make the thing go, I'm not going to let such a minor preference get in the way.
fieroguru MAY 22, 07:49 PM

quote
Originally posted by thesameguy:

Good to know on the DBW. I don't much care for the feel of modern GM pedals compared to the old metal stuff, but ultimately if it's easier to make the thing go, I'm not going to let such a minor preference get in the way.



The DBW pedal in my LS4/F40 swap feels just like a cable throttle. There is a table (Engine, Airflow, Electronic Throttle, Map A normal) where you specify % pedal movement vs. RPM vs. % TB movement in the calibration, so you can tweak pedal response/feel. Installing the DBW pedal is easier than running a cable pedal. Just a flat bracket with 4 holes and run the wires to the ecm and you are done.
Raydar APR 03, 10:23 PM
Holy resurrection, Batman!

Yeah. I know this is an ancient thread, but I was doing a web search for "G6/LS4" swap, and it came up.
Hey, thesameguy, did you ever go anywhere with this?

[This message has been edited by Raydar (edited 04-03-2023).]