So I�m getting ready to start on my first engine build and had a few questions about the machine work I�ll need to have done. I�ve been reading about different builds and whatnot on here for months but wanted to figure some of this stuff out before I start calling shops so I know what kind of stuff to ask for. The engine is a 5.3 from a 2000 Yukon and will be going in to a K5 Blazer. It won�t ever see any boost or nitrous and probably won�t be revving over 6000 rpm either so I�m trying not to go over kill on the parts (ie no forged internals) so I can save money to use on other stuff for the project. I don�t mind spending the money to make sure things are done right but I also don�t want to dump money on premium parts that won�t ever see the abuse to warrant having them ya know? I�m shooting for a torquey reliable engine that�ll be going in a summer cruiser/camping rig so right now the plan is to rebuild and bore out the short block, swap heads (used 243�s), swap cam (custom spec from Tick or Cam Motion in the 205/210 - 212/218 range), and install TBSS intake, TB, and injectors. FWIW I did consider just getting a 6.0 but even higher mileage pullouts run $1500+ where I�m at and then I�d still be swapping cams and whatnot on top of that so I figure rebuilding what I have will be a better and slightly cheaper option. Now that the background and goals are out of the way, on to the questions lol.

1. Is sonic testing required when punching an iron 5.3 to 5.7? I know TMS makes an iron 5.7 and I�ve seen a ton of other people do it own their own 5.3�s but when I tried searching for this the only people I saw sonic checking the blocks was when they were trying to punch the 5.3 to a 4�+ bore and whatnot. A couple of the shops I talked to said they didn�t think it was possible to go from a 3.78� to a 3.90x� but were willing to try. One said they would need to sonic check it and the other said they didn�t have a sonic checker to check it out which is why I was asking if it�s necessary or not.

2. What are the best budget pistons? I saw a few people recommend Speed Pro HE pistons in some old threads but wasn�t sure if a better option has come out since then. I�ve also seen guys put used LS1/6 pistons in but I can only find them online and don�t really know how to tell if they�d still be good/useable or not by just looking at pictures unless there�s a giant crack or something. I don�t want to put cheap garbage in my engine but don�t see the need to spend $700+ on forged pistons either since I�m staying NA.

3. Should I keep my press-pin rods or replace them? This is another one of those things I�ve seen mixed opinions on and some guys re-use them without problems while other guys say they�re garbage and need to be replaced� If I replace them should I just go with some used Gen IV floating rods or is there another good option out there that won�t break the bank?

4. How far should I go with my used 243�s? I don�t really know the history on them since the CL seller said they were from a LS2 Corvette but when I went to buy them they had truck valves and springs (I still haggled him down enough to make them worth my trip). They look to be in really good shape though so I was originally planning on just having a shop clean them up and do a valve job but after making a few calls it looks like just having that done is going to run $2-300 so now I�m tempted to just spend a little extra to send them to TSP for their stage 1 porting package ($750) or maybe AI for their 226cc package ($995). I don�t necessarily mind the extra cost if it�s worth it but I keep hearing how port velocity is more important than flow for making torque (which is what I�m after for a heavier truck) and was worried about losing too much of that. Hopefully that makes sense and isn�t too dumb of a question�

5. What�s a ballpark reasonable cost to have the machine work and assembly done on the bottom end? I�m just starting to make calls but one shop quoted me $400 for the bore & hone and $600 for reassembly with me supplying stuff like the pistons and oil pump while another shop quoted me $2000+ for doing the same thing so it�s kind of all over the board and I don�t know what I should be expecting to pay. I don't have the specialty tools to assemble the bottom end myself so I was planning on getting the engine torn down to just the short block before I take it in and then do the top end myself to save some coin.

Is there anything else you guys think I should look in to or ask the shops when I�m calling around? Any input is appreciated

 

From what I've read people have them sonic checked 3.901+.

Just go for some used LS1/6 pistons on a stock 5.7 bore (3.898 IIRC). You're not pushing it, and finding used slugs in good shape should be easy. Just make sure the tops don't look like they were hit with buck shot and they have been cleaned up first for a good look at them. Also, make sure the skirts don't have grooves. Inspect the ring lands and pin bosses under the crowns.

For the money, just go for the Gen IV floaters and be done.

A good port job should preserve velocity. For what you're doing a budget port job would be worth it over just having them cleaned up at the machine shop. I'd look at that TSP stage 1 port job, although AI does some killer work.

Ballpark $850-$1000 for a full prep plus $500-$700 for assembly. Add another $150-$250 for balancing.

 

Hi, call Rex Hutchison on Auburn Blvd in Sac. I have had many engines built there over the last 20 years and his quality is good, BUT his prices are commensurate w/that quality.

He can let you know what is needed. They generally don't miss anything on rebuilds and unlike most hacks will give you a build sheet with clearances.

 

As far as the heads go, do your self a little looking on this site. xRaTeD and another user has some great videos on home porting. They show you what to take out, and why. I did mine, and you can still bearly see the casting lines in there, but they flow much, much better.

I have under $100 in equipment, and probably 25-30hrs in them. It would have cost ~$400-$700 to have this done.

 

Thanks for the replies so far guys.

93Z2871805 - Thanks for the pointers on checking out used pistons. Don't think I'll be able to check all of that stuff though the pictures though so I'll probably just go with new ones unless I find a reputable seller on here. I tried looking through some of the online catalogs for stock-type replacement pistons but was only seeing ones for the .945" press-fit rods so I guess using Gen IV floating rods isn't going to work either.

03EBZ06 - Rex Hutchison is still on my list of shops to call. So far I've talked to Mother's (reasonable prices but no sonic checking ability) and Motor Machine (more expensive but knew a lot more about LS building). Is there anybody else in the area you'd recommend? I don't mind paying the money for a quality rebuild but if the price gets too high I might start looking in to buying a short block from one of our sponsor's instead.

rpturbo - I did think about trying to do a home port but I haven't worked up the nerve yet lol. The other thing holding me back is the time involved since I don't have much left at the end of a 60 hr work week...

 

Why are you looking at machining it at all?

I trust GM to machine an engine more than I do most shops and mileage doesn't mean what it did a few decades ago.

The extra boring work to go from 5.3 to 5.7 size is extra cost, balancing is extra cost and most shops wont do either as well as GM did. There is some risk of damaging pressed pistons removing them from the rods. Once the rods are opened up to remove from the crank they should be reconditioned, again more cost.

Bet you find that a used 6.0l used without disassemble would have been cheaper. Real chance too that a lightly modded 5.3l would surprise you power wise, a K5 came with what 210hp max, a stock 5.3 being at least 285, 243s and TBSS intake will take that up over 300, think the stock motors like that are 315, then consider cam, tune, headers all adding some.

Shortblock is a very expensive place to spend money with relatively little return, there comes a time in modding where it is warranted, but for a sub-6000rpm build it is likely just money pissed into the wind.

 

For the price of the rebuild, wait time and finding a good competent machine shop , it will be better and cheaper for you to get the 6.0. I just got my engine rebuild for my l92, cost me around 6 k total in the end and 5 mos of downtime. And it's not even for a bigger ci build. Machine work is not as cheap as you think it will be and the downtime is ridiculous .

 

and then too few local shops are actually competent..........

 

To answer your questions in order...

1. Sonic testing takes 15 minutes tops, I run the probe through the bore on any block that's going more than one oversize up from standard, the 5.3L blocks that I've tested had no problem being punched up to LS1 bore size.

2. Good shape takeout pistons would be fine for what you're doing, the skirts would need to be checked for proper taper, and the ring lands checked for lateral clearance. If you can't find them, then a hyper replacement series piston would be fine from Sealed Power.

3. The early pressed pin GM rods were absolutely horrible as far as machine work goes, it's easy to get takeout late model bushed rods to upgrade your build with, I think I have a half dozen sets just laying around.

4. On those cubic inches with the application that you're talking about I don't see the cost-benefit to porting 243's....a good valve job by a shop using the right cutters and then blending the bowl will pick up the flow where you want it.

5. Pricing will always vary from region to region, and greatly depends upon the level of quality and attention to detail. I guarantee you that a $200 hone job on an LS1 does not include properly torquing the mains and using deck plates, and likely the guy also doesn't hold himself to tight tolerances by allowing for cool down time and instead is doing a production quickie job which is unacceptable with these late model engines with very thin ring packs - you'll end up with oil consumption and short ring life.

For comparison purposes my prices would be ~ as follows..

$500 for oversize bore + torque plate plateau hone
$400 for performance valve job and seat blend - 5 angle intake and radius exhaust
$80 R&R cam bearings
$80 R&R pistons on rods
$800 to assemble short block, includes setting ring gaps, oil clearances, degreeing the cam.


I have extra LS1 and 6.0L iron blocks around for building engines for customers, I always try to tell people that it's worth calling the shops first to see if they have prepped cores waiting to be built before getting your own at the junkyard.

 

I really don't know of anyone else in the area I would trust. Good luck w/your build up.

 

Thanks for the replies and advice guys. The reason I wanted to do a rebuild on the short block is because everything else (top end, trans, transfer case, etc.) are all getting rebuilt before they go in to the truck so I figured I might as well do it too and get a few more cubes out of the motor while I was at it. The reason I wasn�t planning on just picking up a 6.0L is because they run a huge premium where I�m at. After talking to several wrecking yards in my area the going rate for a higher mileage (150xxx) Gen III started at $1500 and the price jumps up to $3500 for a lower mileage (40xxx) Gen IV take out and nobody wanted to tear one down so I could buy the short block by itself. I still have a few more calls to make but it looks like I can get an over-bored rebuild done for around $1950 by a reputable local shop or have an Iron 347 shipped to me from TMS for basically the same price. Plus this is a project vehicle that I�m still acquiring parts for so time isn�t a concern.

machinistone - Thanks for some good advice and comparison prices. I never thought to ask about prepped cores either, thanks for the tip. Where about are you in North Bay? I�ve been all over that area for work (PG&E) and always really like it.

 

I'm in Sonoma County.

 

I 2nd 93Z