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ImI I'm curious if anyone has done this already and how it's working out?
I watched Swapology's video about an L83/LS7 they were using for testing and thought I'd build one too. I had a customer with a leftover LS7 intake and throttle body and some LS3 injectors. I'll make a custom harness for it starting with a van harness and wire in the new connectors from the donor L83 harness. All the ICT conversion parts showed up yesterday...just waiting on the motor.
Curious about how tuning has been with the high compression and port injection?
Sorry for no updates, the L83 I bought ended up being much worse than I thought. The block is at the machine shop now getting .020 over and honed. Bummer, but I think it's for the best since I will probably go with Wiseco -.5cc pistons to lower the compression ratio to 10.5:1 or even lower with the -8.5cc pistons. Since this will be a port injected motor on pump gas or E85, the 11.5:1 is too high. I'll have some pictures of the adapters and the LS7 intake when I get the block back and built up. I got an LT5 camshaft from Scoggin-Dickey since it has the lifter shape for no-AFM and I will probably use a VVT limiter in the stock VVT cam gear. I was looking at saving some money and using a Gen 3/4 variant piston but with the reversed intake and exhaust valve position on a gen 5 I think going with a dedicated piston is best.
Got the long block done. Bored .020 over and Wiseco pistons to drop compression to 10.5:1. I had gen4 rods laying around so I had those balanced with the Gen5 crank and pistons. ARP main studs and ARP head bolts with new GM head gaskets. Bolted on the heads and ICT adapters and looks pretty good with the LS7 intake.
I used an LT5 cam and springs that were very reasonable to delete AFM. I'll keep the VVT for now and maybe play around with it a few degrees to see if it helps.
This seems like an overly complicated way to go and you end up loosing the best part of the GenV engines, the DI...
Help me understand why this is better than a Gen4 5.3L swap, if you are going with port injection anyway...
Andrew
11:1 compression, nodular main caps, gusseted water jackets, 12mm head bolts, piston squirters, cast-in cylinder sleeves, oil pan that's easier to remove in-car, dime-a-dozen in junkyards, etc....
Why would you not want to use it? What's complicated? All you need to do is change a few plugs on a gen 4 harness and it'll run on an E38. I'm working on one right now.
11:1 compression, nodular main caps, gusseted water jackets, 12mm head bolts, piston squirters, cast-in cylinder sleeves, oil pan that's easier to remove in-car, dime-a-dozen in junkyards, etc....
Why would you not want to use it? What's complicated? All you need to do is change a few plugs on a gen 4 harness and it'll run on an E38. I'm working on one right now.
Exactly what he said, I'm not discounting DI, but if you already have an LS swap and want an affordable aluminum block these are the way to go with ICT intake adapters. Remove AFM with a factory LT5 or L8T cam and run a high flow factory intake....too easy.
The heads are also not designed for a wet mixture in the runner. Plus the manifold to cylinder head match is no where near close. Hi Ram would have been my choice. But for the sake of just doing it, why not.
Exactly, why not. The plan for this motor and truck is to be a test bed for different engine and wiring harness configurations. I kept all my direct injection parts so I can go back, and I will have to when I go to SMOG the truck. I started with the LS7 port configuration because I got the manifold and throttle body for nothing. I'm making the wiring harness from a CTS-V LSA harness with an E67 so I can easily swap to an LSA blower next. I have access to a chassis dyno so the end goal is to have 3 numbers to look at: LS7 port injection, LSA forced induction and then back to DI. All on the same block, cam and transmission/rear end. The DI setup will be slightly handicapped with the lower compression pistons, but there are many L83 baselines out there for people to compare.
Dyno tests have proven that adapters cost horsepower from extremely poor flow transition.
Most of the upsides you've mentioned to the Gen 5 engine aren't really problems on gen 3 or 4.
A better version of something that wasn't an issue to being with isn't really better.
Is there enough room to run the factory DI with this intake and adapter system? Looks very interesting as a solution to run secondary injectors on these DI engines...
I got the motor running in the truck. I ended up having to drop the flow rate of the injectors way down to get it to run, so I'm thinking I have some bad injectors. Once I get the registration I'll do some street tuning on it with the cam in the current 0 position and then hopefully 2, 4, 6 and 8 degrees so I can make a close approximation of the LT4 cam advance map. Then to the dyno to see what it does.
Motor is in and running. I had a bad MAP sensor and a bad electric pedal so it ran TERRIBLE at first. Now that I have it set to MAF only and Open Loop with a wideband it's much more drivable. I ended up putting a Camaro pedal in and I need to make a new mounting bracket as I'm only able to get 30% pedal travel before it bottoms out on the floor. No fun with a 30% V8...but easier on the rear tires.