LSX vs Big Block

[Bumblebee2012]

Not to mention that I haven't seen any math on this compression ratio, no tall about how far below deck you are going for and no talk about the chamber volume after this shave. I assume by that that your paying someone that can put you in the right place? You need to spend some time with a calcatuter before you start ordering parts and firing up the Bridgeport.

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[Bumblebee2012]

Not to mention that I haven't seen any math on this compression ratio, no talk about how far below deck you are going for and no talk about the chamber volume after this shave. I assume by that that your paying someone that can put you in the right place? You need to spend some time with a calcatuter before you start ordering parts and firing up the Bridgeport.



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[2012 Mustang GT]

Don't know if 54 CI and shaving the heads will get you 120 HP either...I would contact one of the vendors on here that builds engines and talk to them and see what they say. And if your goals of 750 NA flywheel HP is attainable for a reasonable budget off of an LS3. Takes money to play and you are better off spending more upfront to get more reliable power than just sheer numbers. You are wanting to build off of a 1LE so sounds like road racing is what you are after. You definitely want something thats going to hold together for some miles and have an engine with a healthy power curve not just a peak number.

[Jims Mongoose]

Originally Posted by KCS

You can't bore an LS3 to 427ci. You would either have to hone it to 4.070' bore and use a 4.10" crank, or sleeve the block and then you can go to a 4.125" bore and use a 4" crank. Either way, you will need REALLY good heads and a relatively large cam to make 725hp at the flywheel.

Personally, I like the saying, "there is no replacement for displacement". Years ago, SAM built a 468ci BBC (stock crank, rods, and cheapo KB pistons) with oval port heads (to BBC guys, they're about as desirable as LS1 853/341 castings) and a carburetor and made 636hp. Total cost was probably around $6k for everything.

Thanks again to all. Let me lay out what my goals are better. I think the 1LE is a precurser to the Z28 which is the car I like best. Leaner meaner and more sleek than the ZL1 with no supercharger; again that's what I want, no blower. But I want alot more than 505 HP coming from the LS7 and I want the amenities of the 1LE. I want a car that is muscle car but that is super quick in a straight line, but that handles like the 1LE. Thats how I got to asking these questions.

So to KCS, you are not the first one on this thread to say that I can't go to 427 reliably. Okay so I have to modify my goals. But I don't know some of the lingo.
What is a BBC?

To Mustang 2012 and Bumblebee, Sounds like the shaved heads and increased compression is an expensive tricky route with alot of top quality engineering and builder required.

So if I redirect my goals, what specific changes can I do to leave it normally aspirated and get 660 HP at the crank. Please include the mod and suggested manufacturer. I am trying to learn. I know engine basics well, but not the current hands on stuff in the actual hands on mod world.

If the 660HP is possible, can I do it in logical steps.
426 to 550 and then 550 to 660 HP

Will the 1LE drive train take that power?


Jim

[2012-2SS]

You may want to look into this:

http://www.jegs.com/p/Chevrolet-Perf...75108/10002/-1

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[Jims Mongoose]

Originally Posted by 2012-2SS

You may want to look into this:

http://www.jegs.com/p/Chevrolet-Perf...75108/10002/-1

Sent from my Galaxy S3

Near the beginning of this thread I mentioned that exact engine, but it was the complete engine making 740HP and costing about $15000. Problem with that engine is that it will be alot heavier I believe than the LS3. If in fact if it is not heavier it may be a way to go.

I would like to do this a little slower, building the performance and resting my pocketbook in the process.


Jim

[KCS]

Originally Posted by Jims Mongoose

So to KCS, you are not the first one on this thread to say that I can't go to 427 reliably. Okay so I have to modify my goals. But I don't know some of the lingo.
What is a BBC?

BBC = Big Block Chevy

I'm not saying the 427ci LS3 is unreliable, but 725hp at the flywheel from 427ci AND good drivability is a lot to ask of a naturally aspirated engine (granted "good drivability" is subjective). We make 600whp pretty regularly out of our LS7 cars, which translates into ~690-705hp at the flywheel, but they tend to be a little rowdy for daily driver duty.

[Jims Mongoose]

Originally Posted by KCS

BBC = Big Block Chevy

I'm not saying the 427ci LS3 is unreliable, but 725hp at the flywheel from 427ci AND good drivability is a lot to ask of a naturally aspirated engine (granted "good drivability" is subjective). We make 600whp pretty regularly out of our LS7 cars, which translates into ~690-705hp at the flywheel, but they tend to be a little rowdy for daily driver duty.

Your comments coming from someone who actually builds them is always sobering. You are right, what is rowdy for the street is subjective. That is why I started this thread. The poster before 2012 2SS suggested the LSX crate motor. In the long run it may be what I need, but I don't want to destroy the handling of the 1LE. What are your thoughts on that?

By the way as the title says, I just go my 1LE 2SS with dual mode exhausts. Black on Black. No RS. If I decide to go Halos I'll do it later.

A few short drives both at night so I could not do much, but WoW.
Unbelievable. If you can't get a ZL1 and the new Z is just too much of a race car without amenities this is the One.

Handles like a beast and the close ratio box is awesome even on the street. Anyone saying that the dual mode is a waste ---- oh no.
Again awesome.
I'm actually a little rusty with the stick. My last stick was my 1969 Ram Air IV gto. (don't even ask about selling that car. What a mistake.) Anyway in a few minutes it came back fast. Clutch a little stiff but it's new.

This car is an awesome base to build what you want. You can have a straight line muscle car with upgrades that will make most anything think twice, and around the turns well I'm Italian so 'forget about it'.

So to all continue to suggest what route I should take.

One more thing, I had started a thread awhile back about what I percieved as lag in the SS auto's that I drove and even the ZL1 auto and to some degree the SS stick. I can tell you we had all kinds of opinions and good thoughts on that thread. Most pointed to AFM and some to break in required and one gentleman talked of 'toe to throttle' response that the companies mess with.
Well this baby does not hesitate one bit. I don't know why but it just responds quickly. Love, love it.

Will post pictures tomorrow.
Jim

[2012-2SS]

A few extra pounds from an iron block isn't going to "kill" your handling. In fact I doubt you'd really feel much of a difference. There's a few guys on here who have the LSX 454, do a search and ask em.

Also I should clarify that I started this thread for a completely different reason. :hijack: I don't care though, I got out what I needed in the first few replies.

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[KCS]

Originally Posted by Jims Mongoose

Your comments coming from someone who actually builds them is always sobering. You are right, what is rowdy for the street is subjective. That is why I started this thread. The poster before 2012 2SS suggested the LSX crate motor. In the long run it may be what I need, but I don't want to destroy the handling of the 1LE. What are your thoughts on that?

I would prefer a sleeved block instead of the LSX block. I like the LSX a lot, but I was disappointed with the length of the cylinders in the standard deck blocks. The cylinder length is a big determining factor in how much stroke you can use in an LS engine, and the aftermarket sleeves for the LS engines is about 1/4" longer. We like to sell ERL's line of shortblocks, in this case I would suggest their M7 Dry Sleeve shortblock with the longer 5.80" sleeves, which uses a 4.185" bore and 4.125" stroke crank for 454ci. Rather than LSX versus Big Block, you get the Big Block displacement in an LSx.

[AG454]

Having recently gone from a LS3 to a LSX 454, I can say I don't notice the extra 80 lbs. or so. I don't road race my car, maybe you would notice it there. I do notice the extra low end torque.

[Jims Mongoose]

Originally Posted by AG383

Having recently gone from a LS3 to a LSX 454, I can say I don't notice the extra 80 lbs. or so. I don't road race my car, maybe you would notice it there. I do notice the extra low end torque.

Great Information. That is probably what I will do.

Did you buy the Complete 454 and just put it in.

Does it just mate up to my 1LE clutch, tranny and stuff.

Any thing you can tell me about sway would be helpful.

Jim

[AG454]

You will need a 8 bolt flywheel and the clutch of your choice. The crate engine comes sans intake and oil pan. It takes a LS7 type intake manifold, the Camaro pan and everything else will swap over.

[Jims Mongoose]

Originally Posted by AG383

You will need a 8 bolt flywheel and the clutch of your choice. The crate engine comes sans intake and oil pan. It takes a LS7 type intake manifold, the Camaro pan and everything else will swap over.

Just to clarify, I did not start this thread, 2012 SS did and thanks for that.

I am beginning to think 454. Wow, this could easily take me to 750 normally aspirated.

I'm drooling, wonder if Hennessey and crew do this stuff?


To 2012 SS. I apologize, didn't mean to steal thread. I was thinking of another that I had started and had a brain fart.



Jim