LRS Economy shortblocks *forged*

HankyGT

Member
Jan 15, 2006
81
3
6
Warren, OH
Anyone ever use one or hear anything about them? Anyone actully making any power with them?

Was contemplating it for $1400 to my door with the forged pistons. I mean I would assume it's a strong as factory setup that people seem to be able to break the blocks on? I've been having a hard time convincing myself to drop mega $ on a stroker that's going to do the same thing anyhow.

I'd like to carry over my exact same setup of:
AFR 165s 58cc/stud
FRPP 1.6 rrs
tfs stg1 .499/.512 221/223 @ 112
42# injectors/ Areomotive 1:1 reg
Lightning MAF
190lph intake
T-rex inline
Edelbrock Performer 5.0 u/l intake
75mm tb
Vortech s-trim (8-10 psi pulleys)....makes 11psi with power pipe
AFM powerpipe

Most make decent power with this on a stock block. Wanted to add a 331 but I'm just going to break it anyhow.

My goal is @ 430-450rwhp


Any and all opinions can be shared :nice:
 
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If you're pushing 450, your flirting with block upgrade territory. While the LRS-6009EF forged piston shortblock will handle a good deal of abuse, FRPP has a smoking deal on a shortblock kit right now. Its a BOSS block, forged crank, rods, & pistons with rings. Basically a build your own bulletproof shortblock setup.

Ford Racing Performance Parts BOSS short block kit

We could put you in that kit for $1899.99 & shipping is only $14.99.
 
Yeah, I know it kinda sucks about the block thing. That is a really good deal though on that BOSS setup. I'll have to talk to my machinist and see what it's going to cost for assembly.

I see it will need allign honed for the crank and I'm assuming it is a rough bore? The only 'problem' I forsee is the -6.6cc reliefs. With my 58cc heads I can see this putting me close to 10:1 which is getting out of the safe zone with a blower. That, and the fact that I thought you could not use the tradional 7/16s style headbolts and traditional cylinder heads with that setup. I will also have to do the math on actual displacement.
 
Yeah, I know it kinda sucks about the block thing. That is a really good deal though on that BOSS setup. I'll have to talk to my machinist and see what it's going to cost for assembly.

I see it will need allign honed for the crank and I'm assuming it is a rough bore? The only 'problem' I forsee is the -6.6cc reliefs. With my 58cc heads I can see this putting me close to 10:1 which is getting out of the safe zone with a blower. That, and the fact that I thought you could not use the tradional 7/16s style headbolts and traditional cylinder heads with that setup. I will also have to do the math on actual displacement.

LOL I guess if I would have paid a little closer attention I would have seen that you listed 58cc chambers on the head! Unfortunately you'll also be pushing almost the same compression (approx 9.7:1) with the LRS-6009EF. Heck, you're pushing that now with a stock bottom end probably!

Is your motor still operational? You may be best off just buying a good set of dished pistons & re-building your existing motor for the time being.
 
just curious not to hijack the thread but is the boss block finished as far as machinig? also what other parts would you need so it can be finished? ie oil pump ans stuff like that that are boss specific
 
just curious not to hijack the thread but is the boss block finished as far as machinig? also what other parts would you need so it can be finished? ie oil pump ans stuff like that that are boss specific

The block will need finish work only, ie - honing the cylinder walls. The deck, lifter bores, & mains are finish machined to low end specifications & may need minor tweaking for your application. None of this is out of the ordinary for a new block & any machine shop will expect it. The block includes all of its proprietary plugs & dowels. You will need specific head bolts & oil pump pickup, & FRPP recommends the use of their head gaskets.
 
That, and the fact that I thought you could not use the tradional 7/16s style headbolts and traditional cylinder heads with that setup. I will also have to do the math on actual displacement.

Yes, I went to the FRPP site and it says this:

"Designed for M-6049-X306//X307/C3/D3/Z304DA cylinder heads. Not designed for production 302/351W or M-6049-Y302/Y303/X302/X303/X304/X305 cylinder heads"

Is this because the block is drilled for 1/2" head bolts? If one were to have their production-style 302 heads drilled for 1/2" head bolts, would they work then? Other than that I'm not sure why they wouldn't work. :shrug:

Either way, for 1800.00 that is a freakin' steal! Anyone know how much power these blocks can handle "safely"?
 
Yes, I went to the FRPP site and it says this:

"Designed for M-6049-X306//X307/C3/D3/Z304DA cylinder heads. Not designed for production 302/351W or M-6049-Y302/Y303/X302/X303/X304/X305 cylinder heads"

Is this because the block is drilled for 1/2" head bolts? If one were to have their production-style 302 heads drilled for 1/2" head bolts, would they work then? Other than that I'm not sure why they wouldn't work. :shrug:

Either way, for 1800.00 that is a freakin' steal! Anyone know how much power these blocks can handle "safely"?

You got it! The reasoning is because of the head bolt size. Pretty musch all of your aftermarket heads (AFR, TFS, etc) use 1/2" bolt holes. If you were to have a set of 7/16" hole heads drilled to 1/2", you could most definately bolt them up.
 
Common runner aftermarket 302 heads do not use 1/2" headbolts. Only heads setup for large displacement setups. AFR 165cc & 185cc heads both use 7/16", as do the majority of the mainstream TFS line. 205cc + tend to go with the larger bolts.
 
Common runner aftermarket 302 heads do not use 1/2" headbolts. Only heads setup for large displacement setups. AFR 165cc & 185cc heads both use 7/16", as do the majority of the mainstream TFS line. 205cc + tend to go with the larger bolts.

Hmm... my TFS street heads are about 6 or 7 years old now, but they were drilled for the 1/2" bolts and came with hardened washers to use 7/16 bolts if needed. Just an FYI.

Scott
 
Common runner aftermarket 302 heads do not use 1/2" headbolts. Only heads setup for large displacement setups. AFR 165cc & 185cc heads both use 7/16", as do the majority of the mainstream TFS line. 205cc + tend to go with the larger bolts.
You're right on the 165s, they do have 7/16" holes. The 185 & up have the 1/2" holes & according to TFS all of their heads are drilled for 1/2" & require a reducer bushing to be bolted down to a production 5.0L block.
 
isn't there something about the deck height on the boss 302 blocks that makes them unsuitable for a stroker application?

i think i read that over on hardcore50

so the bottom line is that if you want to use a boss block, you are pretty much forced to stay 302 with it.

but the boss 351 blocks can still be stroked

please correct me if i am wrong about this.
 
isn't there something about the deck height on the boss 302 blocks that makes them unsuitable for a stroker application?

i think i read that over on hardcore50

so the bottom line is that if you want to use a boss block, you are pretty much forced to stay 302 with it.

but the boss 351 blocks can still be stroked

please correct me if i am wrong about this.

Huh. I'm definately no expert, but the production 5.0L block was 8.2" deck height as well & there are more of those blocks running stroker rotating assemblies out there than anyone can count. Seems that the BOSS block would be just as suited for it considering FRPP also offers BOSS block based 331 & 347 crate engines.

I'd be interested to read up on that from some more experienced individuals. I'm all about learning as much as possible!