LS4 / F40 swap - fieroguru (Page 97/216)
dobey JUL 18, 11:19 AM

quote
Originally posted by fieroguru:
I am ditching DoD for a camshaft with more power and better drivabilty.



Have you thought about retrofitting VVT as well, or done any research on it? I did a bit of research into how the VVT on the newer Gen IV engines works, last night, and am now leaning very strongly toward going with VVT on my build. It of course limits the cam choices again, but allows some pretty interesting things with balancing performance and economy too.

Just curious what your thoughts are on it.
ericjon262 JUL 18, 01:27 PM

quote
Originally posted by dobey:


Have you thought about retrofitting VVT as well, or done any research on it? I did a bit of research into how the VVT on the newer Gen IV engines works, last night, and am now leaning very strongly toward going with VVT on my build. It of course limits the cam choices again, but allows some pretty interesting things with balancing performance and economy too.

Just curious what your thoughts are on it.



FWIW, Mast Motorsports does VVT LSx cams
dobey JUL 18, 01:32 PM

quote
Originally posted by ericjon262:
FWIW, Mast Motorsports does VVT LSx cams



Yep, so does Comp Cams, Texas Speed, and several others. They also do DOD cams. Ran across plenty of them yesterday when searching for info on how the LSx VVT setup works.
fieroguru JUL 18, 01:53 PM

quote
Originally posted by dobey:

Have you thought about retrofitting VVT as well, or done any research on it? I did a bit of research into how the VVT on the newer Gen IV engines works, last night, and am now leaning very strongly toward going with VVT on my build. It of course limits the cam choices again, but allows some pretty interesting things with balancing performance and economy too.

Just curious what your thoughts are on it.



Yes, I have looked into it. My engine is already a Gen 4, the E67 ecm is already setup for VVT, and has the tables populated so I think the conversion would be fairly simple - add the VVT hardware + timing cover, wire it up, see if it works, then tune it.

The only real issue is the timing cover needs a little more than 1" of additional room between the timing cover and the water pump for the VVT hardware to fit. switching to an electric water pump would be about the only way I could do it w/o having to completely rework the whole accessory drive to shift the balancer/belt out the needed amount, which puts it in the middle of the frame rail. But I don't want to run an electric water pump.

My next 2 electrical upgrades would be:
1. see if the LS4 E67 ECM will run my swap w/o transmission - concern is speedo input function
2. upgrade will be to flex fuel. I just need to add the sensor to the return line and run a couple wires to the ecm. I will need larger injectors and fuel pump too, but then I can switch to running E85 which is about $0.80/ gallon cheaper than the 93 octane it uses now. Then I can tune it for E85 as well and limit the MPG. I could still fill up with gas if I travel to place w/o flex fuel. The tables are already in the E67 LS4 calibration.

The rest of the summer is going to be quite busy with 2 more brake kits to launch (12" kit for Hybrids - 84-87 front/88 rear and the 13" for the 84-87), the LS4 flywheel/starter bracket launch, making some modified decklid hinges, and starting 1-2 other personal swaps... so the LS4/F40 Fiero probably won't get much attention for a while.
dobey JUL 18, 03:58 PM

quote
Originally posted by fieroguru:
The only real issue is the timing cover needs a little more than 1" of additional room between the timing cover and the water pump for the VVT hardware to fit. switching to an electric water pump would be about the only way I could do it w/o having to completely rework the whole accessory drive to shift the balancer/belt out the needed amount, which puts it in the middle of the frame rail. But I don't want to run an electric water pump.



I haven't really looked at the Gen V engines much yet, but I see the Ecotec3 truck engines have a water pump that routes over top of the VVT hardware on the timing cover, and hang off to the driver side of the engine. It looks like it doesn't hang out as far as the LS4 manifold does, and the thermostat is back up top. I don't know if it will bolt up to the Gen IV engine yet though. Still have to dig a bit to see. If they do though, they could be a pretty good option for people doing LS swaps who want a mechanical pump, with a custom exit/fill tube at the thermostat similar to the stock 2.8, and possibly converting the intake port on the pump to an angled connection (or cutting it off and welding up an exit to the rear, to be more suitable for the Fiero.

The Gen V engine also has the new variable displacement oil pump, which will help slightly with MPG and avoid torque loss. If it will fit the Gen IV engines as well, I think I might install one on my build.

On the subject of E85, the Gen V has a sensor on the feed line that measures more accurately the content of ethanol in the fuel. I don't know if the signal is the same between it and the older system though. If it is, then maybe it would be a better option. The tech article I just read about it in, stated that one would no longer need to wait until an empty tank to switch between E85 and regular fuel in the trucks, like is necessary on the Gen IV flex fuel engines. I don't know enough about how that works yet, to say if it would be good for you, but it might be something you want to look into before doing the conversion, if you're going to add flex fuel capability.
fieroguru JUL 18, 05:12 PM

quote
Originally posted by dobey:
I haven't really looked at the Gen V engines much yet, but I see the Ecotec3 truck engines have a water pump that routes over top of the VVT hardware on the timing cover, and hang off to the driver side of the engine. It looks like it doesn't hang out as far as the LS4 manifold does, and the thermostat is back up top. I don't know if it will bolt up to the Gen IV engine yet though.



They will physically bolt to the block, but the ports are wrong. The top hole is still round, but its a different diameter and offset (not the issue). The bottom one is rectangular on both engines, but the rectangle is 90 degree from each other, so there are areas of the ports that won't seal up with a normal gasket. The other issue is the "inside" of the belt is 4 5/8" from the block vs. the LS4's about 1 1/2"... so a shimmed LS4 pump to clear VVT will still have the belt closer to the engine than this pump.


quote
Originally posted by dobey:
On the subject of E85, the Gen V has a sensor on the feed line that measures more accurately the content of ethanol in the fuel. I don't know if the signal is the same between it and the older system though. If it is, then maybe it would be a better option. The tech article I just read about it in, stated that one would no longer need to wait until an empty tank to switch between E85 and regular fuel in the trucks, like is necessary on the Gen IV flex fuel engines. I don't know enough about how that works yet, to say if it would be good for you, but it might be something you want to look into before doing the conversion, if you're going to add flex fuel capability.



I am not sure where the fuel sensor is in the OEM Gen 4 engines (might be in the tank somewhere), but the guys converting to flex fuel are putting the sensor in the return line (which was my plan), which should work just like the Gen 5 setup. The E67 ecm has a table to change the stoich A/F ratio for 0 to 100% alcohol in 6.25% increments so it shouldn't matter what concentration of E85 to gas is ran. With the sensor in the return line, it should know the % alcohol that is running through the engine and compensate for it in a quasi-real time fashion (there is a slight lag between the fuel splitting and a portion making its way to the injectors and the other portion going back through the return line. Installing it on the fuel rail (If you have aftermarket fuel rails) might be even better.

I would love to do a Gen 5 4.3L swap, but I want to wait till the tuning software is further developed/understood.

[This message has been edited by fieroguru (edited 07-18-2014).]

dobey JUL 18, 06:01 PM
Ah, well that sucks about the water pump. I finally managed to find a picture and indeed they're wrong. Would need an adapter with Gen IV gasket on one side, and Gen V on the other. Guess I won't be trying that then.

Thanks.

Hopefully the oil pump will fit though. The variable displacement pump is a nice way to get a little drag reduction.
fieroguru JUL 19, 06:08 PM
Now I have the engines for my next two LS4 projects. One is a 92K 2006 and the other is a 114K 2007 - both from Impala's. I only needed one to start my next LS4/F40 project, but the other one had a factory replacement transmission (unknown how long since its been replaced), so I picked them both up. They are complete drop outs (except one is missing the MAF - but I have 2 on the shelf) and I could have had the suspension, but both wouldn't fit with it on and putting them in the bed of the truck would have made it even more overweight. It was a 3 hr drive back home and I didn't want to press my luck too much.

My plans with these is I will do two more LS4 swaps. Both will be bone stock with zero performance upgrades. A custom harness will be the only aesthetic upgrade (both engines have covers), but I will clean them up and paint the aluminum to keep it from oxidizing. One will have the F40 6 speed, the other will keep the 4T65e-hd. Once they are running/driving I will likely sell them either as dropouts (on 88 cradles) or as complete cars. The buyers could have me do some performance upgrades before they pick them up, but I don't want to overbuild them...





Waiting for something to be done with them (the 06 one had a pretty bad power steering leak and oil soaked the accessory drive):



One of the easiest ways to tell an 05/06 (Gen III) from an 07+ (Gen IV) is the placement of the MAP sensor.

07 (right on top of the manifold):


06 (is on the end behind the power steering pump - or not on the top of the intake):


Here is the small difference in the ECMs.
The 07 uses the E67 ecm. It has the longer gray connector:


The 05/06 uses the E40 ECM and has the shorter gray connector:

[This message has been edited by fieroguru (edited 07-19-2014).]

dobey JUL 23, 10:25 AM

quote
Originally posted by dobey:
Hopefully the oil pump will fit though. The variable displacement pump is a nice way to get a little drag reduction.



Looks like the new oil pump won't fit on the Gen III/IV engines either. The pickup is a little different, and the bolt holes and pump outlet don't line up either. So no using the variable displacement pump. :-/
Steelsoul JUL 25, 09:08 AM
Hey Guru

Been lurking on this build for a while and have to say your a master at working on cars.
Have a few questions about some of the tools you are using.
What kind of brake are you using to bend the steel?
And I would really be interested in the LS4 with the auto transmission once you are done with it.

Keep up the good work, I one day hope I have half as much talent as you do