LS engine swap info needed

Printable View

07-01-2009, 02:10 AM
90K5

LS engine swap info needed

I`ve got a 90 chevy K5 blazer and I`m thinking of swapping a 5.3 in it. THe TBI 5.7 runs great but has 227,000 and I figured if I did my research and found out exactly what i needed for the swap it would ether run about the same or just slightly more money than rebuilding my long blockor buying a new long block from GM. I see 5.3`s all the time with fairly low miles complete with all the accesories and harness and ECM for a fair price. I know I`ll need the adaptor motor mounts and the converter spacer so I can reuse my 700R4 and I know I`ll have to hve the harness rewired and the ECM reconfigured but am I missing anything else? Being tha my blazer is a 4wd will I have any clearance issues with the oil pan or exhaust? Can I adapt the later model Y pipe to my current exhaust? Thanks
07-02-2009, 12:16 PM
LS1GMCTruck

Just my two cents, but I don't honestly think this proposition would be a cost effective swap for you...IF dollars are important to you. I can't say enough about the end result of installing a LS series engine, but getting there is more work & money than you might think. For instance. Is this truck your main source of transportation? If it is, you need to line up alternate transportation for a few weeks at least, cause something always comes up during the swap. What exhaust will you be using & who will be installing it? What high-pressure fuel delivery system will you be converting to? etc.,etc.,etc...
07-02-2009, 01:13 PM
90K5

Quote:

Originally Posted by LS1GMCTruck

Just my two cents, but I don't honestly think this proposition would be a cost effective swap for you...IF dollars are important to you. I can't say enough about the end result of installing a LS series engine, but getting there is more work & money than you might think. For instance. Is this truck your main source of transportation? If it is, you need to line up alternate transportation for a few weeks at least, cause something always comes up during the swap. What exhaust will you be using & who will be installing it? What high-pressure fuel delivery system will you be converting to? etc.,etc.,etc...

Well this is exactly why I made this post. I was thinking of adapting a late model Y pipe to my current exhaust and adding any other sensors I may need. It already is fuel injected so it has some. It is my main source of transportation but by the time I get everything gathered up I should be able to come up with another vehicle to borrow for a bit. For the fuel system i don`t know what changes I need. I know the LS engines have more fuel pressure than my current TBI has but I`m hoping I can retro fit a later model fuel pump into my tank or just go with a aftermarket pump. I don`t know if I need to change the fuel lines or not. My original plan was to do a fresh TBI lower end with Vortec heads, GM`s TBI intake for vortec heads and the GM HT383 hyd. roller cam or some other roller cam to help build low to mid range power. I started thinking about the 5.3 because they already make more power in stock form than what i can get from a mild 350 TBI.
07-02-2009, 06:36 PM
LS1GMCTruck

Quote:

Originally Posted by 90K5

Well this is exactly why I made this post. I was thinking of adapting a late model Y pipe to my current exhaust and adding any other sensors I may need. It already is fuel injected so it has some. It is my main source of transportation but by the time I get everything gathered up I should be able to come up with another vehicle to borrow for a bit. For the fuel system i don`t know what changes I need. I know the LS engines have more fuel pressure than my current TBI has but I`m hoping I can retro fit a later model fuel pump into my tank or just go with a aftermarket pump. I don`t know if I need to change the fuel lines or not. My original plan was to do a fresh TBI lower end with Vortec heads, GM`s TBI intake for vortec heads and the GM HT383 hyd. roller cam or some other roller cam to help build low to mid range power. I started thinking about the 5.3 because they already make more power in stock form than what i can get from a mild 350 TBI.

Yes, they do make more power as is. And a lot better gas mileage. And run quite a bit smoother from idle all the way up the rpm range. The fuel system needs upgrading to a 58 psi pump, whether its in-tank or external. Most are using the '99 Vette fuel filter/regulator combo, which requires a return fuel line to the tank. You may be able to retain your existing 3/8" steel tube fuel feed line from the tank forward. An engine fuel line connector is required, as well as connections for the Vette filter itself. Most all this stuff is covered(and more) in the stickys. Who's doing your harness & computer? What fan(s) you going with? Air intake sytem? Radiator? Standard exhaust manifolds or headers?
07-02-2009, 08:47 PM
1 bad blazer

i have 79 blazer 2wd with a 5.3 ,4l60e, 4.10's and 22'' and the swap has set me back about $2500. thats not including the little thing that we tend to forget.i saved money by doing all the work my self . it took about a month just to get it to run and drive . i would work on it after work and on weekends .i fabbed my own mounts ,and fabbed an h pipe . As for fuel i installed a the pump from the donor car into a modified sending unit from a suburban since mine has a 30 gallon tank and not as deep a one from a suburban .you should not have any problems like that since yours already has a pump in the tank. the tb is cable . the harnness is easy orange is 12 volts ,pinks are ignition ,black is ground .there's a bunch of info on this web site helped me alot . you an also use lt1 swap .com there's very good infoon that web site . i also have a nelson tune with all the goodies .http://i47.photobucket.com/albums/f1...o/102_1352.jpg