From what I hear an LS7 can't handle very much boost do to small walls... or something. Forgive my lack of knowledge. But is there any 427 that can handle a good amount of boost from twin turbos? Like, similar to an LS1 TT?

 

Do you mean a LS1 bored to a 427? I would think with proper sleeving it should be fine.

 

Would boring it out to 427 add any additional HP? If so have any idea on a rough number?

 

boring out your LS1 to 427 will yeild a substantial amount of horsepower, without knowing what heads/cam/intake you will use figure each cubic equals 1 horsepower, give or take.

 

^ Yep, would a really solid H/C/I package you could have 500 RWHP Naturally Aspirated with relative ease.

 

That's really awesome. Any idea how much it might run someone($)? Lol..

 

Might wanna give VA speed a call, im sure they have longblocks that are 427s, my guess would be 7-10k depending on forged internals/sleeves/ect

my friends 402 cost him 12k at VA speed and its proven to handle 1500 whp.

Definitely something to look into

 

But I'm not really looking to upgrade the entire engine. That'd be a great alternative down the line but I'm assuming boring would be cheaper and better for me now.

 

are you talking about any 427 or a ls7? the ls7s dont like much boost or nitrous either, the pistons supposedly dont handle it too well. thats why my roomate hasnt put the bottle on his yet, but i have heard of people going tt once the pistons are swapped for forged. but a built 427 should handle boost if built correctly.

 

plus you can't bore a ls1 out that much... The most you can go is about 3.9XX depends on who you talk to there are tons of sponosor >>>>>>>>>>>>>>>>>>>>>
who can help you in your quest.

Fyi I good turbro kit is going to in the 6k 10k range motor is going to be in the same price range and don't forget all the small stuff

 

yup, cant get the ls1 bored out that much. its a badass setup if your looking for 900wheel (probably a little low) on low boost. but like said, there are a TON of sponsors here to help you out! good luck!

 

Depends on how much power you're looking to make.

 

Ok, you are looking into buying an ls1 car correct? It is not as simple as simply boring it out. These are alluminum blocks, and require sleaves to work correctly. Getting a block resleaved is very very expensive, pretty much prohibitively so. What you need to do is look at getting a quality top end that gives you room to grow. I would suggest getting a set of TFS 225 cc heads, and a fast 92/92 (ported), a cam, LTs, and TDs. This will be a good start, and will allow you expand in the future. I know you have been making a lot of posts, and I commend you for your interest, but you should at least get the car before you start discussing TT, and new short blocks. These cars are not slouches from the factory, so enjoy driving the car stock first. Buting the car with the expectation that you are going to move directly into a TT 427 is not only rediculous, but is unrealistic. Believe me, I am not hating on you at all. I understand how addicting this hobby is, and how fun it is to entertain different ideas. Answer to your question is that if you are truly looking to build a good boost motor, why not build a ls2 402, or 418 ls3. You will sacrifice a minimal amount of hp, for a more stable engine under the pressures that FI entails. Typically speaking, 427s are favorites for straight NA guys who plan on running high compression and do not plan on using a power adder. Good luck, and please don't take my suggestions the wrong way. Just chalk it up to a warning from one guy who got in over his head to another.

 

Why bother with a 427??? There are better shortblocks i.e. 408 lq9, 370, 402, and the baby forged 347. No point in that kinda stroke.

 

Yeah that's definitely a good point. I'm pretty sure I'll be putting an LS3 in it but that'll be in a long time (at least 2 years). I suppose I'll be keeping the engine just about stock for a while.

I guess I'm just excited.

 

LOL, your excitment just spent abour $10k in performance mods without even blinking & that was only including a built 427 without another $5-10k in turbo system & fuel system. Then another $2500 for a 9" rear to hold the power. And possibly another $3k in suspension modifications depending on the route you choose.

My suggestion to you is to steady read & do research on this board while you enjoy it in stock form for a while. Then start modding it correctly. Too many people come on here & are only concerned with tryin to make a certain HP & they don't understand what all will be involved to get there properly & safely. After you research for a while you need to try to set a goal for the car. Once you get that decided & locked in, build toward that point. Don't just sparatically mod cause you saw something new come out or say ol' Jon boy running it on his ride. Make sure every mod you do puts you closer to your final goal so you don't have to backtrack b/c you bought somnething out of urge instead of sticking to your build plan. You can lose alot of money buyin parts you really dont need & then tryin to sell them again later.

 

This is why I'm glad these forums are here. I'd ending buying a 427 and f*cking myself realizing I forgot parts.

I know that a turbo would be an additional 7k, but the engine AND turbo would be 17k. But if boring the engine out costs so damn much I'll just save for it all and do it slowly over the next couple years.

 

Well if your gonna want to go up to a 427ci block, your not gonna be boring your stock block. You'll have to pick up a bigger ci LS block & then have it worked over or you can buy a empty 427 block ready for internals.

Someone correct me if I'm wrong, but isn't a 383 set-up the biggest a stock 5.7 LS block can be taken to?? I know for a 402 you need a 6.0 LS2 block.

 

Yeah, above in the thread I was told a LS1 can't even be bored out quite that much. Any idea if an LS3 can?

 

If I were you, I wouldn't even waste my time with boring or anything. Just buy an outright shortblock when the oppurtunity presents itself. Build it with the heads,manifolds, etc.. that fit the exact application. If your looking at making ungodly amounts of power than go with a LSX block which start at $2000 and do what you want to it. They can be bored up to a 512 if I remember correctly and GM claims them good until 2500hp. They are iron, but if you go with a good amount of psi, why not get the damn thing. You might save all of say 75lbs with aluminum. With the kind of mods your doing, your going to have to replace your ENTIRE driveline, powertrain, fuel system, and mess with the chassis. There will be nothing and I mean nothing stock other than the PCM possibly in the car in what it seems your posting.