Advise Needed with Gen IV LS Swap

[88blazerboy]

Hi,

I've got a complete 5.3 Gen IV motor and 4l60e transmission with low miles from a 2008 Tahoe that I am considering installing in my 1988 k5 blazer. I'm pretty familiar with the typical conversion issues for this swap (e.g., motor mounts, exhaust clearance, high pressure fuel, gauges, etc.). What I don't know about is whether or not the Displacement on Demand (DOD) with this new motor will become an absolute nightmare.

I have read a few threads on the DOD topic, as well as spoke to a few guys locally who build race cars and dyno tune. As of yet, I have no clear answers as to whether or not I should sell this engine and look for an LS without DOD. It looks like it might cause some serious problems for me. Does anyone have any experience with this issue?

[Chevydillan]

I have no personal experience with DOD but it's not to difficult to eliminate it. I'd rather do that than try and sell it. Just my .02

[jcrumpley]

Just set DOD to disable in HP tuners and move on.

[88blazerboy]

I have clarified with two different professionals who flash PCMs and build custom wire harnesses that DOD/AFM on Gen IV engines is a feature that can be easily shut off without any sensor modification to the engine. From what I have been told, the only way AFM can still fail after being removed from a re-flash is if the AFM feature failed in some way prior to the re-flash. This makes me feel a lot better about using the engine I bought because, as far as I know, the AFM hasn't failed before.

So, I have a new question about designing the EFI high pressure fuel system for this engine. In short, I'm using my stock fuel tank and lines from the 88 Blazer because I presently have TBI for my original 5.7 Gen II motor, so I already have baffles in my tank, metal lines, and a return line. It has been said by others who have done ls swaps with similar blazers that a fuel pump from a Chevy pickup with a 5.7 engine between 1997-99 will drop right in to my tank and produce 58+ psi, but some folks say you need the fuel sending kit too, and others say that you do not. Does anyone know whether I would need a fuel sending kit too? New, they are very expensive (about $450.00). If I need it, I'll try my luck pulling one from a bone yard.

Thanks!

Got my Dirty Dingo motor mounts yesterday. I'll have to post some pictures of them on the engine in a bit. I probably will not be able to do the R&R until the second week of September.

[Skylark]

So, I have a new question about designing the EFI high pressure fuel system for this engine. In short, I'm using my stock fuel tank and lines from the 88 Blazer because I presently have TBI for my original 5.7 Gen II motor, so I already have baffles in my tank, metal lines, and a return line. It has been said by others who have done ls swaps with similar blazers that a fuel pump from a Chevy pickup with a 5.7 engine between 1997-99 will drop right in to my tank and produce 58+ psi, but some folks say you need the fuel sending kit too, and others say that you do not. Does anyone know whether I would need a fuel sending kit too? New, they are very expensive (about $450.00). If I need it, I'll try my luck pulling one from a bone yard.

Thanks!

Got my Dirty Dingo motor mounts yesterday. I'll have to post some pictures of them on the engine in a bit. I probably will not be able to do the R&R until the second week of September.

AC Delco EP381. It drops right in where the current pump sits and runs up to 60psi and will flow 155lph. $58.85 from Amazon.
http://www.amazon.com/ACDelco-EP381-.../dp/B000C9SHOU

[88blazerboy]

Thanks Skylark! I'll check the pump out. I sort of hit the bone yard today and pulled a pump and fuel sending kit out of a 1997 Suburban. I wouldn't dare use the pump, but if I needed the kit, I think it would suffice. I've never messed with fuel tank guts before, so it's all new territory for me.