L31 Extreme Budget Build

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Scooterwrench

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Most of the GM vehicles I have owned use the 4 port valves. IMO it would be easier to retrofit a 4 port than a 3 port. The vehicles with the 3 port valve had a somewhat goofy metal pipe with 3 fittings on it. If you want to keep the coolant bypass to the radiator, the 4 port is the easiest way.
I think it was you that mentioned an electric HCV that could be controlled by adding a switch on the blend door actuator arm so I've been looking for a 4 port HVC that is electrically operated. I haven't found such an animal. There are plenty of vacuum operated valves so my thought is to use an EGR control valve to operate the HCV. Seems like the hard way to do a simple task.
 

L31MaxExpress

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I think it was you that mentioned an electric HCV that could be controlled by adding a switch on the blend door actuator arm so I've been looking for a 4 port HVC that is electrically operated. I haven't found such an animal. There are plenty of vacuum operated valves so my thought is to use an EGR control valve to operate the HCV. Seems like the hard way to do a simple task.
Not that I recall, seems a bit complex. Some big trucks and buses use a solenoid operated 4 port valve.
 

Scooterwrench

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Not that I recall, seems a bit complex. Some big trucks and buses use a solenoid operated 4 port valve.
I found 'em and ouch! Reckon I could tee off the A/C clutch wire to operate and electric valve but I kind of wanted to shut the valve off anytime the temp setting was at cold so my vent temp would be cooler. Sometimes you don't need A/C,just cool fresh air.
 

L31MaxExpress

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I found 'em and ouch! Reckon I could tee off the A/C clutch wire to operate and electric valve but I kind of wanted to shut the valve off anytime the temp setting was at cold so my vent temp would be cooler. Sometimes you don't need A/C,just cool fresh air.
I have used a ball valve for years to do that. Here in Texas, stays closed about 8 months out of the year.
 

L31MaxExpress

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I made a couple WOT rips on this thing today. It screams for what it is. I will also be the first to admit, I screwed up in the tune setup and had the thing targeting a 14.7:1 WOT AFR, although I do remember setting it for 12.5:1. Oddly it did not spark knock but then again currently conservative on the timing with only 29* total timing at 4,000 rpm. I need to get some 91 in the tank and give it some timing to see how it is really capable of running. I also overshot the adjustment on the TH400 governor. At WOT even with the kickdown not currently connected, it bounced off the 5,500 rpm fuel kill a few times before I lifted a bit and let it upshift. 5,500 rpm is right at 60 in 1st gear. So I have some adjustments to make but otherwise it is an animal and it does not even feel like it has a torque curve, just grunt everywhere. Feels like it pulls equally hard from off-idle to the fuel kill. Pin the throttle, sets you back in the seat and it goes. I would guess 0-60 was about 6 seconds. Remember this pig is only ~4,500# curb weight as it is largely an empty shell with only 2 front seats and the stock TH400 converter is stalling about 2,600-2,700 rpm behind this L31 setup. It gets up into the torque curve quick and pulls.

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L31MaxExpress

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Front end re-assembled hopefully for the last time. Worked a little more on finishing the harness up as well. Will soon be ready for some actual cruising. Rear shocks arrive wednesday and the fronts are already installed. Went with KYB Gas Adjust Monotubes

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