It’s been a while since I’ve done any updates for the S10 project so here it is:
As mentioned in a previous post I decided to go a different route with my ’06 Silverado and ’85 S10. The more I thought about it, having a 450rwhp daily driven 5200lb. truck isn’t as fun as having a weekend toy that’s 2000lbs. lighter and offers the same power. It’s simple math to some, but don’t get me wrong it’s a LOT of fun to have a quick full-size truck. The motor build post described in a nutshell what’s going to happen to the LQ4, but I’ll go ahead and go in further detail here.
The motor is a ’07 LQ4 motor that was a pullout of a insurance fire vehicle. I got a steal of a deal on it mostly considering the condition of the motor is mint. There’s obviously less than 5k, if not 3k, miles on the block. There’s no signs of any abuse and there’s barely any carbon on the piston surfaces. Once I saw the block I knew it would be just fine to build up with a stock bottom end. The ’07 block has the updated LS2 rods and crank as well as a ported OEM oil pump and some other nice goodies that were late renditions to the original mesh of a LQ4 and LS2 block. Thanks to Matt (TooTall) he picked up the motor for me while he was out of town. So enough with the basics, what’s going in it?
After doing some research on the new L92 heads I figured that since it was such a cost-effective route I would just do that. It was an easy decision to make after reading the Car Craft article they had written up using a stock LQ4 shortblock. I thought about using an actual LS3 intake manifold, but I really want to see what kind of numbers I can make with the OE L92 truck manifold before I swap to something else. Besides, I got the complete manifold with throttle body, injectors, rails, sensors, etc. for 125 dollars with less than 5k miles on it. The manifold setup came from a LY6 hummer, and the heads are brand new never installed GM complete castings. I will be doing a separate post that will further describe the actual part numbers you need to make the swap work as well as some compression ratio figures and all kinds of other small things that I learned in the last few months.
Well, I have a set of stock heads, a stock manifold, and a stock shortblock. What else am I going to do? That was pretty easy to answer once I decided to just put the motor in the S10 I’m building. Given the weight of the S10 a pretty high-revving cam setup will go in the motor. I spoke with some buddies over at G-Force and we came up with something in the 236/242 range with whichever lift Comp Cams recommends for use on the XER lobes. Most likely I’ll go for a 115 LSA, but I might end up with a 112 since it’s not a daily driver and I won’t mind it being incredibly choppy. To help out the bottom end when spinning to 7000 RPMs I opted to get ARP main and rod bolts. These will definitely help out with the added compression from milling the heads and also the increased revs. Besides that, I’m using relative stock parts in the motor. I will however be using a set of nice dual springs and some hardened pushrods. Since the motor didn’t come with lifters I decided to buy a LS7 lifter set, which happens to now be the recommended OE service number. These new lifters have enhanced oiling characteristics which allow them to be used in higher RPM applications. For really high RPMs, GMPP recommends using the CTS-V R lifter set which are apprently fine up to 8000 RPMs.
Compression ratio is an important question in this build. I know that eventually I want to turbo this motor, but I also want some good N/A power. I’ve come to a happy medium where if I get the heads milled a little bit and use stock gaskets I’ll be at or around 9.9-10.1:1 SCR. At this compression a turbo is just fine, and it’s pretty much just like turbocharging a stock LS1 or even LQ9. I’m hoping to achieve 550 crank horsepower, which should net me about 440rwhp given a 20% drivetrain loss through the 4L65E.
Other than the change in plans for the motor, I’ve also decided to go with a nicer fuel system. Although it’s not for super high-horsepower applications, the fuel system I’m building is said to feed up to a 700hp application. Basically I’ll just be using a 99-04 Corvette fuel filter/regulator, Walbro GSL392 external high-pressure pump, and all AN hard lines. The filter/regulator is an easy solution to reduce plumbing and also increase fuel pressure reliability. The filter regulates fuel pressure internally so all you have to do is run one feed line to the engine bay. It’s more efficient and is inexpensive. Otherwise, I would have run an Aeromotive regulator which costs 135 dollars compared to the ‘vette filter which is 37 dollars. The total fuel system including all fittings, the fuel pump, fuel cell, filter, and lines comes to around 500 dollars. Not too bad considering the potential of the system. Note that the fuel cell price includes a sending unit and filler neck, 15 gallons all aluminum.
As for interior, I’ll have more updates on that soon. I plan on getting the electrical done soon once I have a little more room in the garage. That’s about it for now, and hopefully I’ll have more updates soon!