I am in the beginning stages of building a 408/409 motor. I want to put some of the great knowledge from this board together and come up with a "how to" on this motor buildup. I want to assume that we are starting from scratch (engine block only type scratch) and build it piece by piece for a NA street/some strip application. Let's leave the power adders off since they, other than N2O, usually up the price out of the majority of our ranges, hence this is somewhat of a budget buildup (C5Rs are goo-goo eyeing for most). Other things not to worry too much about are things like the cam since everybody wants something a little different. Instead, shed light on "between this and this" then let people choose accordingly.

Yeah there are crate motors out there but who wouldn't stand a little taller knowing that they put in the wrench time and who wants to pay those prices anyway <img border="0" alt="[Banging Head]" title="" src="graemlins/gr_banghead.gif" /> . The information I want to gather is:

1. All of the materials/internals from oil pan to intake and pullies to flywheel that it will take to build this motor (or any other size for those considering the 422s 427s blah blah blah). Bearings, gaskets, electrical, pumps; include it all

2. Prices of different approaches (forged or billet, 2.08 or 2.055, LS1 or LS6 castings, Cola or Lunati,....) and where those prices come from, part numbers would be useful. Maybe even back up your choice with reasons or better yet, results <img border="0" alt="[hail]" title="" src="graemlins/gr_hail.gif" />

3. Misc costs such as balancing, machining, porting, and the like

4. How to put it together. Torque specs, lube this first then...., make sure that this does/doesn't.....

Yes there is a huge debate of iron or aluminum so lets leave that to different application preferences. I am eager to see what we can come up with. Even the smallest info is appreciated.

 

Not everyone all at once.

 

I don't have much to contribute yet but I would like to research this as well. I guess the price to beat is the 409 shortblock available from More Performance for $9K. Looks like a very nice setup.

I don't think a stock LS1/LS6 block can be safely
bored/sleeved to 4.03." The C5R block can be, but is very expensive and the temptation would be to go even bigger than 409 cubes with that much invested. It seems the 6.0 liter iron block is the starting point of choice for a "budget" buildup (if there is such a thing on these engines). An extra 80 lbs or so of weight, but stronger and cheaper to machine. I reckon we could pick up the truck block for a thousand bucks or so and start thinking about what heads we want to work with. The truck heads would be cheap but I read somewhere that inexpensive CNC ported LS6 heads are available through GM? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

 

Yep. Thanks, Joseph. We have the block at $580.00
and CNC ported LS6 cylinder heads at $985 apiece from the General through SDPC. The bare heads are also available for $685 per. This might be a better starting point as the ported heads are sized for stock valves (home porting anyone?). Not bad so far. I am sure we could also consider some of the preassembled heads available from board vendors. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
The block will need to be bored to get to our desired displacement. Any idea what the machining will cost? Then we can get on to our crank and piston options. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

 

I have looked around but haven't found the rotating assembly to match. Where do you find such a specific size? The 9k does sound more like a long block, very overpriced if it's not. I am wanting to save every cent possible by assembling this myself so I can buy that much better pieces. I am assuming that it IS cheaper to assemble this motor myself, I could be wrong. Is it cheaper to pick up a short block from racenet.net or the like?

 

Ok, now were are getting somewhere. So far we have:

Iron block from SDPC - $580
machining boring/honing costs for .030 over?

Bare LS6 heads from SDPC - $685/head
porting (stage 3?) for a 408/409 is probably best left to someone like ARE or MTI, price for head with valves, springs, seats, ....

Total so far: $1,950

 

We may have to piece together the rotating assembly, unless someone like Racenet or TR selling a 382 stroker kit would let us substitute the larger pistons we need. The 4.00 stroke crank and 6.125 rods will work. I am sure we can beat these $7-9K shortblock prices if we work at it.
<img border="0" alt="[barf]" title="" src="graemlins/gr_barf.gif" />

 

409 iron shortblock from ARE is 8000 outright.

600 for bare block
2000-2500 for crank
700-1000+ for pistons.
700 for lunati 6.125" connecting rods
450 for cam
150ish for timing chain
150 for oil pump
200 for ARP main studs

That's at least $5000 there for parts and I haven't put in rings or bearings, nor any machine work.

I'm not 100% sure of what all the machining costs are... but I know an empty iron block machined and bored out is 1250 from ARE.

 

Ya and how about the fact it was put together by a quallity shop with some sort of warranty. Getting all of the clearances right and correct size bearings. Mic`ed all pistons and rod jurnals for perfect fit.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Nasty N8:
<strong>Ya and how about the fact it was put together by a quallity shop with some sort of warranty. Getting all of the clearances right and correct size bearings. Mic`ed all pistons and rod jurnals for perfect fit.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Exactly. It's worth the extra thousand or so to me to have someone working on my motor that is up to date and knows the in and outs of these motors since they were first introduced.

 

Ok, so were are over the $5,000 mark on parts alone (from where and some part numbers would be nice though).

Anyone have experience with machining costs?

Considering for a minute that I/we were to go the shortblock route, what is the 1k difference between ARE and Racenet? Racenet looked like they had more forged material also, what gives?

 

SSLink, it looks like you and I are still thinking the same. I will call a couple of friends that are very knowledgeable to take a look at this post.

 

The 6.0L truck blocks were on sale for $580 from SDPC a few weeks ago. The GM CNC LS6 heads are also reasonably priced, not sure on exact prices, but you can check on their banner link on the right. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Edit: Are you sure the shortblock was $9K? That sounds more like an assembled longblock price to me if they are using the cast iron block, I haven't checked. The 408/409 cast iron block based engines are only cheaper since there is no resleeving process involved and the block is much more economically priced. All you really need is a .030-.035" overbore done to the block and the matching stroker kit.

<small>[ November 14, 2002, 12:50 PM: Message edited by: -Joseph- ]</small>

 

TTT

 

Gentleman:

Lets not forget the most expensive component of this engine that being a great pair of LS6 stage II or at least III Heads which will cost anywhere from 3000 to 4000.00 dollars without no core charge bringing our price up to 8 to 9K dollars. The true power of this engine will be all about the heads and they are quit expensive as we all know, especially top heads from top tuners.

MTI 427 C5 Roadster <img border="0" alt="[Fluffy]" title="" src="graemlins/fluffy.gif" />