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Hey all, I picked up an LSA supercharger from a buddy, so I'm putting together a BOM of parts I'll need to swap into my '71 Nova. I'm looking for some general guidance while I plan out the build. I'm not getting into the weeds with parts (hoses, belts, gaskets, etc.), but feel free to comment with anything important that I missed.
About the SC: rotors look good, very little coating wear. It spins freely with no noise. I will hot tank and replace the coupler.
Engine
LQ4 with LS3/L92 top end
Bored to .030", stock crank
Mahle flat-tops with -4cc LS3 valve reliefs
Heads milled to 67cc
OE head gaskets (.051" thickness)
10.5:1 CR
LG Motorsports G6x3 cam (no officially-published specs, but I believe it's 235/244, .647/.612", 111°)
Holley 90mm cable TB
1 7/8" American Racing long tube headers
3" Pypes exhaust
411 PCM
I am very likely to replace the cam with something more street- and boost-friendly. Recommendations welcome.
Accessories
I have modified truck accessories with a high-mount AC. I cannot run a low-mount AC without pulling the engine and modifying the subframe. LS3 water pump. I may have to get creative with my upper (driver's side) radiator hose.
I'm planning to run an 8-rib to the SC. It looks like I can run corvette-spacing for accessories. LSX Concepts have a high-mount AC, blower drive, and alt/PS bracket) with the OE LSA balancer pulley (12603916). Other recommendations welcome.
I also looked at a 6-rib setup, which would be much cheaper but limit boost. I doubt I'll go this route.
Fuel
I have a ZL1 pump (13592334) with Vaporworx PWM controller. I'll run the LSA injectors (12145849) with LS9 fuel rail (12602070) for the driver's side inlet.
Heat Exchange System
ZL1 lid (12622236), ZL1 pump (22901367), aftermarket intercooler TBD, recommendations welcome. I need to measure
Sensors and Misc
I have the 85(?) mm truck MAF/IAT. I'm guessing I'll need to replace that. The ZL1 lid comes with a "pressure sensor" (12592525), but it's a different PN than the MAP (55573248). What am I missing?
A note on accessories. This post has some good info on bracketry - and it looks like I'm going to need to ditch my LS3 Camaro water pump for the LS3 Corvette/LSA pump, Delco PN 292966 if I want to run a dedicated 8-rib belt to the supercharger. I plan to use the OE LSA balancer, which I should be able to install and run prior to the full swap: the 8-rib pulley is the same spacing as truck accessories, while the 6-rib pulley is at Corvette spacing. So my options with that are to either come up with brackets to pull my existing AC compressor, alternator and PS pump inboard or buy new brackets and possibly accessories. I'm leaning toward the former.
According to LSXConcepts, the LS3 Camaro/truck accessories are 1.5" further out as compared to the Corvette and LSA 6-rib pulley. I found a photo from user Pocket which helps illustrate that. Corvette on the left, LSA middle, truck right. I might be able to use the truck's 4-rib pulley as reference for building accessories.
Question: anyone know where I can find a set of pointy inserts to thread into the block/heads and mark hole locations on a piece of cardboard or metal plate? I can't think of what they're called.
Corvette, LSA, truck balancer for reference. Photo courtesy user Pocket.
It sounded great and had good power. Seems like a lot of people run BTR cams due to the low overlap, but I had no issues.
If you look at the LSX Concept Blower Drive you mention, they state you have to run factory pulleys, so you will only get about 6-7 psi if I recall from the factory blower. You can run a lot more than that on your combo.
That's what I figured, the tight LSA would bleed a bunch of boost. I did the calculations and you're right, 17.5° overlap. I've looked at the BTR cams, and see that they're ground with CamMotion cores. I might give CM a call and get their recommendation, as it will be a street performer with some time on the autocross. The current cam pulls well over 3,500, but it's not always fun to stay in those upper revs while in traffic.
And good catch on that blower drive. No reason to stick with stock pulleys. What accessories are you running on your combo?
That's what I figured, the tight LSA would bleed a bunch of boost. I did the calculations and you're right, 17.5° overlap. I've looked at the BTR cams, and see that they're ground with CamMotion cores. I might give CM a call and get their recommendation, as it will be a street performer with some time on the autocross. The current cam pulls well over 3,500, but it's not always fun to stay in those upper revs while in traffic.
And good catch on that blower drive. No reason to stick with stock pulleys. What accessories are you running on your combo?
I would look at the Cammotion cams. I think you will get a lot more bang for your buck so to speak.
I have no accessories at all besides the alternator. I used the LSX Race Drive set-up, but I would avoid that. I am trying to modify it to accept some sort of spring loaded tensioner. Mine had 10.7:1 with factory heads, LSA with a 2.38" upper pulley, and the cam I posted above. I had 3.70 gears and it would light the tires up at 60 MPH with ease. I also have a meth kit due to the 15 PSI of boost.
I have the HP Tuners tune for my engine depending on what computer you are using. I have a GMPP E67.
I was actually on the phone with CamMotion when they replied here. The tech recommended the 228/242 grind. I mentioned that I drive on the street a lot and see a few autocross runs a year. I'd prefer a fat torque curve over peak numbers, since my current cam is more of a high-rpm grind. I'm still a ways off from that, but things are coming into focus.
Back to accessories: I think I have something figured out to run the 8-rib, at least for the accessories that will run on the 6-rib belt including a high-mount AC. I'll need to swap to an LSA balancer pulley ($150) and water pump ($150) (note: the LS3 Corvette uses the same water pump) and might need to swap PS pumps. I'm going to try to see if I can run a remote reservoir (highly doubtful) with the truck pump before buying a new one. My 105-amp truck alternator will work.
Last edited by hookemdevils22; Oct 23, 2019 at 04:21 PM.
After careful consideration, I realized that I need to run Corvette accessory spacing. I was initially planning to design my own brackets, but I found something that saved me a good deal of time: ICT Billet makes an inexpensive AC/power steering bracket that fits Saginaw Type 2 pumps. It's technically for the Corvette PS pump, but thankfully all Type 2's have the same basic physical measurements. I was able to modify the bracket and drill my pump, which is from a 90s Chevy S10 pickup, to make it work. For reference, here's a rundown of typical Type 2 pumps.
So for a rundown: LSA balancer, LSA/LS3 Corvette water pump, ICT Billet AC/PS bracket, Corvette tensioner, high-mount AC bracket (my own design; ICT billet also sells one). Supercharger drive TBD.
First up, water pumps. Here are the differences between the L99 (truck spacing) and LSA/Corvette. They're basically the same pump with different spacing. L99 pump (top) vs LSA/Corvette pump (bottom) L99 (top) vs. Corvette/LSA (bottom)
Next, the AC bracket. I designed this when I installed Vintage Air. I'm happy that it only required respacing the brackets to pull the AC compressor in 1.5". I also had to cut the forward bracket to install the tensioner. AC bracket - truck (bottom) vs Corvette (top) AC bracket with tensioner
I had to modify the ICT bracket slightly. I had to cut out some material from the back bracket to fit the non-corvette Type 2 pump. The side holes had to be drilled for through bolts. Pump installed. I also had to clearance the front bracket.
Next up was to install the balancer, water pump and brackets. First, pull the balancer and install the new one. Then water pump, then AC/alt/PS. I highly recommend pinning the LSA balancer.
Bye truck accessories! I used a rental 3-jaw puller on the truck balancer. I had to get creative with spacers. I highly recommend pinning the LSA balancer. A friend had his N/A LS spin the balancer, I can only imagine this one spinning under additional supercharger load. Balancer install spec is 37 lb-ft + 140°. You NEED a new balancer bolt and this torque-angle gauge. 37 lb-ft + 140° is a ridiculous torque. Get creative with breaker bars and be careful! LSA balancer installed.
Accessories installed. The Corvette tensioner is close to the 75mm ribbed idler but shouldn't touch with a belt installed. Alternator/PS bracket. PS pulley not installed.
The ICT Billet AC/PS bracket has plenty of clearance for my A-arm, but I had to do some searching to make the pressure and return lines work. The Type 2 pump I have is the attached-reservoir style, and the bracket positions the high-pressure fitting toward at about 8 o'clock (FLA) and reservoir fitting at 11 o'clock. It also seems that only LSXConcepts has a 90° press-in fitting for the reservoir. It's not cheap ($27), but none of the Parker stores could help me, so it's on order. I cannibalized the 6AN adapter fitting used on my previous setup (LQ4 pump) for the high side and bought a 90° 6AN male-female elbow to attach to the existing 90° adapter fitting in my high-side hose. So the high pressure exits the pump, makes a 180° under the brackets. Lots of potential leak points, but it's the best I could do since Parker also didn't have a single 150° 6AN adapter for my hose.
Next up is to make a bracket for the reservoir. I'm going to try to make the OE reservoir work, but it'll probably be much easier to just buy something from the aftermarket.
For reference, here's the pump I have. Mid-90s S10 with 4-cylinder. The reservoir pulls off with two clips. Type 2 power steering pump with attached reservoir
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LSA Build on LQ4/LS3 
