Heck yeah, I'm genuinely interested! I can't wait to see how this turns out!

Here you go!

http://forums.corvetteforum.com/c4-p...es-1400-a.html

 

I mean why not? all the parts are commonly available. of course I'll be using the lt FOUR concept of design i.e. a decent cam 1.6 roller rockers but with forged guts. I'd like to use 6" rods with this combo too. better geometry. Annnnd If all else fails and it's not as great as I envisioned it all I'll just boost it. single turbo or procharger

 

Because...as has been stated many times in this thread. (ready?)

You're going to spend money, to remove power and tq. <That is "why not".

Take the money that you'd spend on that forged 3.25" crank, rods and pistons and put it into other components that will actually increase hp and tq in your 350,(like a 3.75" crank for example, or better yet, ported heads) and you'll be hp and tq ahead for the same or less money.

The ONLY reason this makes sense is if you have some kind of "fetish" for a "327 screamer" -if it's some kind of weird psychological thing for you. Because there is no magic in the number 327.

 

Why not just put boost to the 350 and call it done.
Because you WILL NOT be happy with that 327 it will NOT at ANY point make more power than the 350 will. Unless you are putting a solid cam or 4 pattern cam in it, at 6600+ you will STILL have valve float issues.
And then you could have put a 4 pattern cam or solid roller in it anyway with it being a 350 and have the exact same rpm ranges with more power and torque for still being a 350

To steal from Tom here, there's nothing Magic about 327 cubic inches. There's a reason GM did away with it.

Think of it this way. Obviously you are NOT happy with the power levels of the 350 you have right now. What makes you think you are going to be happier with a LESS powerful engine?
383 that sucker. Profit.

 

I wonder if this perception is the same reason GM did away with the 350 in 2001?

The OP should do whatever he wants that will please him whether it be stroking, or destroking. The glass is half full no matter how the self righteous feel about imposing their will upon others.

I program chips for a guy in Kentucky who puts TPI on 267 and swears by them in his mid 80's Monte Carlo. I support him rather than pass judgment.

 

I bet you make alot of $ off of him too since he's sticking with that 267. Non Revving, completely non-synergistic with the TPI intake Slug Motor.

And yeah there's a reason GM did away with the 350 in favor to the 6 and 6.2 liter engines. There is no replacement for displacement.

What do you think makes more power? a 327 or a 383 with otherwise identical parts?

What do you think makes more power with otherwise identical parts a 327 or a 350?

 

Mavs, if you read *****'s posts, it obvious that he either doesn't know, he's still stuck in the "old days" or he won't admit it at this point in the thread. I asked him the same question pages ago. One of many questions I asked him that he never answered.

Right...b/c YOU'RE not passing judgment on me (and others here)...right?

Another major problem with your above post (seems like all of your posts have major flaws), is this. "We" aren't simply arbitrarily passing judgement on the OP here. He came on here, seeking advice as to whether this is a good idea!! Seeking advice! Do you understand that? That means that he doesn't know. And if you actually READ his posts...it becomes pretty darn obvious that...he doesn't know! So to give him advice that he should pursue spending his money to reduce his power, is simply giving out terrible advice!

Let's look at a quote from post number 1:
No! Most of us do not agree! You're spending money to remove power making potential from a motor. I do not agree. No, OP, you should not do it. That is sound advice.

NOW...for your "glass is half full" as you unwittingly call it, or put another way, to address your more legitimate point about:
"OP should do whatever he wants that will please him"

Here is what I said in my first post, post number 3 of this thread:
Then I said a similar thing again, 4 posts above this one in post #123:
I believe that I am accommodating the OP's "whim" in those statements. If it will stroke his ego, or whatever....fancy his pleasure, to have his "screamer 327 LT1"...go for it. Post up the results, I said. Is it a good idea to spend money to take away power? No. No, it is not a good idea -to answer the original question asked in this thread. That is not "passing judgement". That is a simple fact. It's not a good idea.

 

I have heard this talk so much on another gearhead board that I've frequented for the last 14 years (happen to be a moderator there), that when a member posted a thread entitled "327-350 Fact from Fiction", it was made a sticky. That was 8 years ago. The very same arguments on both sides were made there that are going on here.

I have to side with Tom here. It makes absolutely no sense from a performance perspective to spend money to do what is being proposed.

If you're racing in some displacement-limited class, or weight per cubic inch class, you may be able to justify it.

For any other reason, it's just a plain waste of performance $'s. For most of us, that is money poorly spent.

But, if you really want to spend your money to invent a square wheel, then go for it.

 

So, at what point does this argument you support stop? Why use a 3.48 crank when a 4.25 is available? Should we fault those using stock engines for correct restorations at as waste of performance dollars? If I build a performance 327 should I be faulted for not using a 4.25 crank? It is just plain silly to think everyone does things to fit within a mold of others expectations. Just because some in San Francisco put 2" earrings in their earlobes doesn't mean I'm going to do it?

Therefore, posting condescending comments about the OP in a thread where he's asking for positive assessment is just plain silly. Honestly, my current 350 has less power than my last 327, but that was my choice. I wanted smoother idle with less compression, and went with a smaller head. Was my choice a waste of performance dollars if it serves my intended goal?

Giving ones 2 cents is fine, but when it turns in to pissing and moaning that another is an idiot for choosing something other than what another may chose is a waste of time that would be better served supporting a positive ideal.

Please feel free to **** away. All things equal, larger bore with shorter stroke creates more power.

 

The OP is talking about a LT1 block. So a large (4.125+) bore isn't a option. We are talking 4.030-4.040 bore. And a 4.25 stroke is only going to work in a tall deck block (9.325" deck height). Once again not a option for a LT1. So it comes down to what stroke would make the most power with a 4.030 bore. The 3.75" stroke of a 383 is probably the best bang for the buck out there. So our options are 302(305 .030) 327(331 .030) 350(355 .030) 383 with a 4.030 bore, 396 (4.030x3.875) or 408.2/409 (4.030x4.00).

The big bore(4.125+) short stroke really doesn't apply here.

 

Well, all things are not equal. We're assuming an LT1-based build.

Back to the original post:

False premise #1 - The short stroke does not give great revs, ridiculously high or otherwise. It's not an "advantage". It was just the predecessor to the 350 in the evolution of the SBC.


As already noted, False premise #2.


False premise #3 - Again as already noted, a 327 does not perform right along side the 350 (except in classes where race weight is based on cubic inch displacement).

False premise #4 - the "baby LT1" has a 3" stroke.

No consensus here, obviously.

Sure, start calling around to the aftermarket crank companies and see if one of them will make a custom 3.25" stroke large journal one-piece RMS crank for you. Might as well be forged while you're at it.

All the "big bore/short stroke" arguments only pan out when the bore is significantly bigger than the 4" of the LT1 and produce a displacement close to 350 cid. Since we're talking about an LT1-based build, you are pretty limited with block choices. Yes, you could probably have a custom block made for a bigger bore, but that flies in the face of the "all the parts are commonly available" statement made just today.

The original assumptions are not true in the real world, and all we are saying is the original assumptions are not true in the real world. That isn't condescending, it's just fact. Are you saying we should only post positive comments just to make somebody feel good? I sure wouldn't be very happy if people cheered me on to pursue an unachievable goal just to make me feel good. Of course, I don't appreciate being called a fool when I'm just ignorant, but I do appreciate people giving me information that educates me.

 

^Well said. I remember all those OLD debates from that forum too.


Totally irrelevant. Several of us have conceded that if the OP has psychological reasons (rather than logical ones) for doing this, then he can go ahead and do it. That's not what this thread was about though, and that is not why the OP asked if it was a good idea. The OP asked if it was a good idea. Why can't you "get" that?

Summit Racing sells a whopping ONE sbc Crank with a 3.25" stroke. It's over $630.00. You are advising the OP "being positive" as you say, to spend $630.00 to lose power. That is called "giving bad advice".



Irrelevant. You met your goals. The OP's goals are a "high RPM screamer". He can meet those goals more quickly and easily by NOT changing the crank.



Pot...meet kettle.


Who disagreed with that?? You'll have to quote where someone disagreed with that. Oh Wait! You won't do that! You haven't quoted where someone said what you claim they said yet...in spite of numerous requests. While you're at it, how about you tell us how the OP is going to get a "big bore" with that LT1 block? (I made that point WAY back on page on, also)

 

First there are Deck Height limitations to consider. (which is why I'm most likely building a 400 in the very near future. So I can have yet even more torque and bottom end. Which by the way unlike that 267 build, plays right into the strengths of TPI)

which limits just how long of a stroke you can really have in an engine.
So, you built your 327. Found it wanting because it wasn't streetable when you could have built an equally powerful 350 that was considerably more street mannered. Or even better built a 383 with the same performance, and even -better- street manners than a 350 and decided because it's more streetable that the Smaller Engine was obviously Better. Rather than the more correct assumption, that you built an engine towards the upper limits of what it's capable of, but never really went to the wall with more cubes.

You a believer in the Butt Dyno too?

No one's pissing and moaning. Except for you, that the rest of us decided to follow the OPs request and Give Our Suggestions based from an honest perspective. And you want to talk about condescending? I bet my 5.7 TPI right now could smoke that 267 that you keep tuning for your buddy without mine even trying particularly hard.

To say nothing if everything comes together, and I get my 6.6 TPI together.
(Gee I wonder why I'm going to a 6.6 liter... It can't be because GASP more displacement equals more power? Nawwwww that can't be! It flies in the face of Mr ******* and his buddy mr TPI 267s completely erroneous world view!)

Now THAT is me being condescending. Maybe you should retire to the bush league. Because I've got more snark in my pinky than you've got in your entire body.

All other things being equal. Yes. No one's denying that. But here's the thing.... they won't be equal displacement. A 327 is SMALLER IN DISPLACEMENT than a 5.7. A 327, is 5.35 liters. That is 400 ccs less volume. For it to make up that gap it would have to move 400 ccs more air at any given point. Done obviously through RPM. But here's the problem. Any rpm you can build a 327 for, you can build a 350 to match it, and it will walk all over the 327 at everything under top rpms due to the larger displacement. Period.

So to answer the OP's question again.
No. It's not a good idea. It's not saving you money, it's not going to generate a lick more horsepower. It's not even going to give you more RPMs to play with either.

A 383 will do everything you want to accomplish, aside from being able to put a "327" chrome emblem on the side of your car somewhere and have it be honest, for a great deal less money. And you get the added benefit having gobs more torque thanks to the longer stroke across the entire rpm range. You might even pick up some mpgs if you loaf it.