98Z28MASS- I really don't think I'd gain 10rwhp/tq for the $2800 spent on a 347. Sure, I could put a bigger shot on the forged internals, but that still doesn't address the low to mid-range punch that I'm looking for. If I re-use my heads figure:
$1500 for stroker crank
$1000 for machining and assembly
$200 for forged pistons (Diamond or similar)
$300 for fasteners and bearings
$200 for misc like gaskets and stuff
$300 for a cam to match the bigger cubes

$3500 total and maybe I can sell my current cam for $150

Does this sound accurate? It seems a lot cheaper than buying a long-block...

 

Ben:

I am in the process of building a 383 too! My parts are suppose to be here either today or tommorrow. I too have a tr224/224/ 114 cam. I went with the 383 due to having a new Ls6 block....which will get a .005" over bore. I got the kit from Scoggin Dickey for $2300 plus shipping and other parts put me around $2500. I have not priced out machine work as of yet. I live in your local area..Va Beach. I will be running my ported stock 98 heads, but I am looking in to getting a valve job. I am still looking at heads too, but money is tight. The 383 should give more low end and shift the power band a little lower....like 500rpm off of peak. My cam peaked at 6.2k and held on to its power till 6.4k. I am expecting this cam now to peak around 5.7 to 5.8k and drop off at 6.3k. Now this is what is is going in. www.ls1miata.net/gallery
I figure the 383 should get this 2600lb. pig rolling of the corners a little harder, and should make highway runs from 60 on up stronger.

 

You forgot about forged rods....I would say $5k until its all said and done...all the ARP hardware is close to $500 if that is what you are going to use. New valvesprings too.

 

turbotacoma-when you say "other parts" for $2500, what did that include? How comprehensive was the SD kit? What brand crank? Are you going to assemble it yourself? I have a 234/236 nitrous cam currently and would probably go with a 24x/24x in a 382/383ci. Sorry about all the questions...drop me a PM if you want. Thanks! Ben

 

Honestly I have been pricing things out for a while in my head trying to see what the best way to go when I eventually need a new block and the costs of piecing one together with the stock 346 comes out to just about the same cost as buying a new balanced block from one of the sponsors. However, if you do all your own work, such as machining your old block, installing and balancing all the parts, etc, then it can be done cheaper, however in my case I dont have access to all of the necessary tools to do so and dont have a whole lot of experience building an engine so when i do need a new one im gonna go with a built short block from one of the sponsors. They have built 383 short blocks as well if you want to go bigger cubes too. Here is one of the links to the short blocks:
https://ls1tech.com/forums/sponsor-sales-specials/438901-huge-ffhp-short-block-sale.html

Again if you can do the work yourself and are comfortable building the engine then bya ll means go for it but if your like most of the guys on the board and dont have access to all the tools and machinery needed to build and balance a block then getting one from one of the sponsors isnt a bad deal at all IMO. Also not trying to steer you away from bigger cubes, just saying you can hit over 600+ rwhp with a 346 with a healthy shot of nitrous on a built block.

 

I'd have to send out the machine work and assembly as I don't have the proper equipment either... I guess I'll look at 402 long-blocks, but then we are talking about $9000 when everything is said and done.

 

just curious as to where you found forged pistons for $200.00??
cheapest I have found was around 5 bills for Mahles, and they go up from there.

 

I haven't priced the pistons in a while, so you may be right. I'll have to look around more...
To add fuel to the fire, Thunder racing has a 383 stroker short-block for under $4K. I don't think I could do a 402/408 for that cheap...

 

Mine was $9k til it was all said and done but that was with new heads, injectors, fuel pump, 90mm...

 

If you reuse your heads and current cam then all your would really need is the short block and whatever other accessories youd need to run it. If you want go the 383 route and reuse your heads/cam/intake until you can afford to upgrade if you dont feel like dropping $10K on an engine now. Otherwise if your gonna go with new heads, fast 90/90, diff. cam, etc then get the 402-408 option. Plus remember you will be able to sell of your current engine and recoupe a few thousand dollars if you go with a whole new engine.

 

Have Abacus do the machine work, they will hone it, balance the rotating assembly if needed, and gap the rings for you. I assembled mine in my garage with a torque wrench and a piston ring compressor. Make sure the block gets clearanced for the rod bolts with the extra stroke.

 

Check a local board.... tidewaterracing.com and maybe you might find some assistance locally.

 

Have you checked out FFHP current sale in the group sales thread???
I just ordered my FI 408 shortblock from them, I went with a different piston which added some to their advertised price. Since I needed heads anyway this was too good to pass up on........$3385.00 for a shortblock and no trade is going to be hard to beat!!

 

good forged pistons are going to run close to 800 with pins and rings.

 

thats funny, cause I had my heads reworked to 2.08 valves and they picked up from .500 up and it gained zero hp. runners were bumped to 235cc and the bores were opened up slightly. this was with a .64X lift cam. if you can try and find a set of stock casting heads with better low and mid lift numbers. I bet you cant. I would be VERY curious to see how a set of ETP 240 heads would do. I would like to hit 600rwhp with a hydrauic cam though.

I would guess going to a 11.0:1 SCR would drop me a good 20rwhp.

 

Yeap that is funny,
Man you are just saying that years of running bigger flowing heads was futile, and everybody was just waisting their time.

With the kind of compression you're running you should be making more than 550.
4% x 1.75 = 7%
550 x 7% = ~38.5 hp is the ballpark of what you would be loosing by going 11.0

Just accept the fact that saying "you do not need bigger
heads for bigger cubes, and they wont make you more power" is not the correct thing to say.
Shoot, even the AFR 225s (relatively small runners) have bigger valves and are opened to bigger bore size.

 

I would bet 40rwhp loss going to 11:1. You'd be surprised.

 

no, I'm not saying that. just trying to say high lift numbers .600+ mean very little.

guess my 408 is just a POS according to your calculations