Hey All,

I finally decided to pull the trigger and do an LSx swap on my car. I came across a pretty good deal from a member on here for an LM7 with good mileage (80k-ish) complete engine minus the starter, with front accessories, ecm, and harness out of a 2003 Tahoe. it has the 862 heads.

My goal for the engine/car is to be a fun street/strip weekend cruiser. it will not be a daily driver, but will still want to maintain some sort of drive-ability out of it. I would like to be somewhere in the power range of 400rwhp if possible. and obviously I want to do this on some sort of a smallish budget. I plan to collect the parts as I can find good deals on them throughout the year and hopefully do the swap all at once next winter.

The car currently is an 84 Trans Am with the L69 and 700r4 transmission. it has 3.73 gears and basically everything on it currently is stock.

any and all input is greatly appreciated.. so for right now my engine build (rough) plan goes something like the following.. please be as critical as needed with your responses.. I don't want to mess anything up or waste time/money on stuff.


Engine:
-Keep bottom end of engine stock (do rod bolts need upgraded?)
-Oil pan (having stock truck pan modified to not hang down so low)
-Clean, degrease, paint, etc block to make it look nice
-Rebuild Heads (is this worth it)

• fix broken manifold studs (one on each head)
• milled to raise compression (worth it? and if so how much)
• upgrade springs (I want to put a semi aggressive cam in, certain type of springs?)
• push rods and rocker arms (do I need to upgrade these?)
• valves (should I replace/upgrade or just have them reworked?)

-Cam (suggestions on a good cam is welcomed)
-Lifters (do I upgrade?)
-ls1 or ls6 intake
-ls1/ls6 fuel rails and injectors (any specific size?)
-long tube headers from racing innovation
-I'll probably rework the truck harness myself
-not sure if I am going to attempt to modify the front accessories or replace


I'll add more as it comes to me haha!

 

Excellent! Can't have too many of these swaps! Working on mine, myself!

Some input on your questions (quite a lot gleaned from this site, and a few others).

Rod bolts: Personally, I'm sticking with stock unless there is damage. Already pretty darn strong from factory.

Pan: That's the slightly cheaper way to go. I'm going to just get the F-body pan kit as I don't feel like trying to fix the stock pan, myself

Heads: I've debated about it as well... and right now, I'm just going to replace the rockers and push rods as mine were pretty oxidized and gooey. Unless you get an LS9 cam (don't recommend it), the stock 1.7 rockers should work fine. Maybe upgrade to beehive springs, at most. Depends on which cam you go with, of course. 80k miles really isn't that much for these motors. For my build, I'll either upgrade to different heads or just mill mine for 2" intake valves.

Cam: I've been back and forth on this. Originally decided on an LS6 cam, but this article now has me heavily considering the Crane Direct fit cams.
http://www.hotrod.com/how-to/engine/...st-comparison/

I'm going with their 1449121 cam. The allure of using stock head components is nice, especially for the budget-minded.

LS6 intake flows better than the LS1.. and you pay for it too. Some outrageous pricing on fleabay right now for intake, rails and injectors. I'm holding out for a decent priced intake by itself, then going to get the rails and injectors separate unless I find a really good deal.

Lastly: Accessories. Modifying is, of course, rewarding in and of itself.. but potentially time-consuming and the chance of messing it up is always there. I went ahead and bought relatively cheap brackets for the F-body accessories, and worked a deal with a guy that owed me money that works at O'reilly. Both P/S and Alt bracket ran me a total of $100.

GL on your build!

 

only reason I am modifying the truck pan is because I have a seasoned Aluminum welder who is going to do it for me for a case of beer haha! a lot less than buying an fbody one and still having some clearance issues with the crossmember without notching.

 

That's a great reason to do that, then. lol

I have access to that option (though not for a case of beer, sadly), but I'm sticking with the F-body pan set.

 

also that cam is very impressive.. opened my eyes a little too haha!

 

I know! After seeing the numbers, it's hard to resist.

Only thing that got me was the price, but for what I'm planning I really can't complain. Funny thing is, I only spent $400 on my motor so just the cam alone costs more.

 

Their LS6 cam in that hotrod article does not come close to the actual specs of the early or late LS6 cam specs. Take their results with a grain of salt.

 

I was actually looking into the tsp 224r seems like a popular choice

 

I'm using a Comp LSR 227/235 614 - 621 lift on a 113 LSA on my 5.3L. This cam is designed for a smaller bore LS engine and was recommended by Martin @ Tick Performance. My motor has been bored to a 3.824" bore with flat top pistons, 2.00 intake valves in the stock 862's.... LS6 intake with long tunes and a T56. Should be between 350 to 375 wheel with this cam... if your looking for something with a choppy idle and power under the curve then it may work for you as well...