[camaroman7d]

Killer, I guess we are just looking at this from two totally different perspectives. You keep saying "stock" where in his post did he say he had a stock 350 cast crank that he planned to use. This is why I say there are not enough details to give good advice. Maybe he has a forged 350 crank and a set of H-beam rods, along with light weight pistons, this would change the whole discussion. To me it seems he is gathering info to make a decision. I just want all the info to be out there for him to make a choice. I am not trying to steer him either way.

I personally spun my old 385 short rod (stock 400 rods 5.565") nodular cast crank to 6500 regularly. That very engine is still together in my friends Nova. He has a bad habit of over rev'ing it (not used to an engine with that much power and that revs so fast). Despite that it is still healthy. If the parts are matched and balanced well. A little stress relieving, beam polishing, shot peening, goes a long way. Too many people think you just buy stock parts and throw them together. That's not the best way to get the most out of the parts. A bone stock 350 will not want to spin to 6500, I agree. This is a HOT ROD site so I assume when building these higher HP engines most of us know to use the proper parts or to modify the stock parts to live.

Now you said you have a friend with a 434 built out of a stock block, that in itself goes against the things you are saying. Most people (that know) will tell you using a stock 400 block to build that engine is not "recommended". I know people do it and that's proof just how strong some stock parts are.

When I say maxed out, I was saying if you got everything possible out of the engine with no limitations and both wee built equally. I don't want to get into awhat if this and what if that, situation. I was speaking in general and not listing specific parts or combinations. I was only trying to prove a point that you can't flat out say one engine is better than another without knowing more details and what the engine/car will be used for. There is more to it than cubic inches.

Royce

[killerformula]

Originally Posted by camaroman7d

A cast crank and stock rods will spin 6500 and live.

Originally Posted by camaroman7d

A bone stock 350 will not want to spin to 6500, I agree.

This is part of where my confusion lies. I guess what you were saying was if you modify those stock parts appropriately, you can make due with them?

Originally Posted by camaroman7d

Now you said you have a friend with a 434 built out of a stock block, that in itself goes against the things you are saying. Most people (that know) will tell you using a stock 400 block to build that engine is not "recommended". I know people do it and that's proof just how strong some stock parts are.

Well you could look at that either way. We're talking about a guy who's spent 30+ years working on GM motors and tunes drag cars regularly. He knows exactly what to look for in a block and happened to find a good one, which he also had to use a short fill on. This is definitely not an endeavor for the faint of heart, and I really don't think it speaks to the strength of stock parts that much. This is kind of like the example of the engine masters making a 12.5:1 motor run great on pump gas. Doesn't mean street motors should be run 12:1, it means there's a guy out there who really knows is dog doo and can make it happen. Again, you and I have different perspectives, lol.

Originally Posted by camaroman7d

I personally spun my old 385 short rod (stock 400 rods 5.565") nodular cast crank to 6500 regularly. That very engine is still together in my friends Nova. He has a bad habit of over rev'ing it (not used to an engine with that much power and that revs so fast). Despite that it is still healthy.

See, to me this sort-of contradicts the point of the 377. Here you're telling me a 3.75 stroke motor is living with stock components all the way to 6500 and beyond. So if a 377 and a 400 with reworked stock components can run to 6500 reliably, we've lost another reason to entertain the idea of building the 377.

Originally Posted by camaroman7d

When I say maxed out, I was saying if you got everything possible out of the engine with no limitations and both wee built equally.

Yep, that's one of the things that perplexed me. We have to arbitrarily dictate in a rather a priori fashion that a 377 normally will live with its (again, for the sake of argument) reworked stock components X number of RPMs further than a 400 and thus prove its efficacy to build. My problem with that is that very few people have run a 377, fewer still have a similar 400 for purposes of comparison and that leaves us saying "a 377 spins better." Which is a statement rather void of meaningful data. I guess that's also what you meant when you said "not enough data to make a decision per application etc" so perhaps we agree on this point.

K

[Bumpstick]

Ah what the heck...

I just plain prefer a short stroked engine to begin with... Simply take a light weight 3.50 stroke crank which can be had for a fairly moderate price... Add a set of light weight rods (Howards makes some great sportsman light weight pieces) and some very light weight pistons (prefer J & E`s) add a set of Dart Pro 1`s (230`s...?) a huge solid roller cam and

"a 377 spins better."

Everybody runs a 400 but the 377 concept was born because a few years ago alot of the great componets we have for 400`s did not exsist... But someone had a brain storm and decided to try a 350 crank in the 400 block (of course made special bearing spacers) and found the damn thing even with a cast crank would turn mega RPM and hey that allowed for more gear which in turn also allows for more flexability in the setup...

Put it in a light setup and it will fly... Also in a street machine this has the same impact as the 427/454 debate did (TORQUE)


Also one last thing put a set of 180 degree headers on it and it would sound like a whole swarm of hornets... Make all the ricers heads spin a 360


dat .02 thang...

[camaroman7d]

LOL, this is almost funny now.

You can have two engines that both will spin lets say 7000rpm. That doesn't mean they both have the same powerband, so just because my 385 would go to 6500 doesn't mean it would be making as much power from lets say 5500-7200 as a 377. Once again it comes back to the whole basis of building a performance engine COMBINATION period. That is really all there is to it. If you "need" more cubic inches to make your goal or your combo work then by all means you should build the larger engine. I'm just saying many time less cubes will get the job done if the rest of the combo is there. Way too many variables to even argue the point. I will just leave it at this, you cannot say a 400 is "better" than a 377 in every way. It just isn't that simple. Bigger "can" be better but, smaller can beat bigger and does more than you know. If that is the way you want to look at it, that's fine (no harm).

If the way you thought was "reality" then all big blocks would be in the 8's or better and no small blocks would be able to break into the 10's. The fact of the matter is there are some outrageously fast small blocks out there. I am not knocking a larger engine, I am just saying make the combination right either way.

Royce

[406 ss monte]

bigger should be better, but my old 327 has smoked a many big block cars of all makes. then turn right around and have some young phucker with a 5.0 mustang smoke me. it's all in the COMBINATION! i've took my same 327 & out run a few 406's & 383"s. they would get me out of the hole, but i would come on strong on the upper end. & yes stock cast 3.25 (307) crank with "b" rods & arp bolts & i spun it 6,800 rpm for four years. the last day it was running i had dosed a gt mustang out in front of where i worked at (5 cars), & on the way home at around 2,500 rpm it let go.

[killerformula]

Originally Posted by camaroman7d

If the way you thought was "reality" then all big blocks would be in the 8's or better and no small blocks would be able to break into the 10's. The fact of the matter is there are some outrageously fast small blocks out there. I am not knocking a larger engine, I am just saying make the combination right either way.

whoa buddy, that was never my message. My simple message is the same one that's been understood throughout the ages, cubic inches = potential for power. This is fact. I never said a smallblock can't be fast, or that a motor with fewer cubes than another can't beat a larger motor. In fact I've said the opposite of that at least once in this thread.

Reality is this: if you want to get into the 8's and you have a 400 block, put a 400 crank in it, not a 350 one, and you'll be glad you did!

K

[swvalcon]

I've got a 377 stroker in my drag car.Works great in light car 2800 lbs. revs fast some times to fast making it hard to keep up with shift points. Turns between 7600 and 8000 with trw forged pistons.Motor has about 600 runs on it with nothing but new bearings and rings every couple years.Stock Chevy rods with polished beams,shot peened, and arp rod bolts, stock Chevy steel crank.

[NXS]

Originally Posted by swvalcon

I've got a 377 ...Turns between 7600 and 8000 with trw forged pistons....Stock Chevy rods with polished beams,shot peened, and arp rod bolts, stock Chevy steel crank.

I believe you. Try that with a 400 crank. a couple of twenty passes at 6500 and you'll be looking for your balancer or changing main bearings.

And contemplate this:

6500 rpm 110mph 26" tire
4.56 gear

7500 rpm 110mph 26" tire
5.30 gear

That's a lot of extra grunt you can pick up....more than 23ci will make for you.

[topfuel]

Originally Posted by camaroman7d

LOL, this is almost funny now.

You can have two engines that both will spin lets say 7000rpm. That doesn't mean they both have the same powerband, so just because my 385 would go to 6500 doesn't mean it would be making as much power from lets say 5500-7200 as a 377. Once again it comes back to the whole basis of building a performance engine COMBINATION period. That is really all there is to it. If you "need" more cubic inches to make your goal or your combo work then by all means you should build the larger engine. I'm just saying many time less cubes will get the job done if the rest of the combo is there. Way too many variables to even argue the point. I will just leave it at this, you cannot say a 400 is "better" than a 377 in every way. It just isn't that simple. Bigger "can" be better but, smaller can beat bigger and does more than you know. If that is the way you want to look at it, that's fine (no harm).

Royce

I have built a few of the destroked engines for both drag and circle track. If a customer runs alot of gear and likes hi RPM, I build the short stroke engine. If they run less gear or if a customer has a big budget, then the long stroke engine is in order. If you really want a nice little RPM loving package try a 4.125 bore with a 3.25 stroke. It yields 348 cu. in. and revs like you wouldn't believe. I built one for a customers drag car in a cu.in. / lb class and he was more than pleased. It's all about the COMBINATION.

[camaroman7d]

swvalcon,
Exactly my point. Sounds like you have it dialed in.

topfuel,
I have a friend that ran a engine combo like you listed, it was a VERY fast rev'ing engine. I can see where it would be a LOT of fun in the right car.

You just can't say COMBINATION enough. That is the whole key to a well performing car (no matter what size the engine is).

I am not sure where people get the RPM limits of "stock" parts. I have a buddy with a drag 66 Nova. He built a budget engine 383 (not one I would recommend) it had the same type of nodular cast crank I mentioned earlier, with stock GM rods (not bushed but, machined for full floating pistons/pins), huge roller cam, tunnel ram, etc... he shifted the thing at 8000RPM the crank is fine to this day.

If things are set up right, balanced, the stock stuff will take some insane abuse. I don't like to push the limits like that but, I have no issue with spinning a well built small block (even with stockish parts) to and above 6500.

Royce

[Odium]

Glad I found this thread, I'm currently wrestling with which to build, 380 (4.165 bore x 3.480 stroke) or 415 (4.165 bore x 3.800 stroke). After pricing them both out the 380 is quite a bit more simply because of the quality of parts needed to turn those rpms reliably. To turn 8k with consistancy you'll need a solid roller package, rev kit, shaft rockers, splayed block, great bearings, good rods, and good rings, and that's just to be able to rev that high relaibly. The 415 doesn't quite require that quality of parts, but it'll make slightly less power but more TQ. The 380 long block, built the way I want it, will cost about $2600 more than the 415. Here are the exact parts I'd have in the 380 short block;

J&E 10.4:1 CR forged pistons
Crower Maxi-Lite 93 Stage-4 6.0" billet I-Beam rods
4340 forged crank
Oliver splayed caps
file-fit plasma moly rings
ARP main studs and rod bolts
SFI damper and flexplate
internal balance

And this is NOT for a regular street/strip motor. I'm looking at a serious bracket competitor. It'll be going in a 3000# car with tall gears so I think it'll be able to take advantage of the quick rev of the short stroke. Any advice?

[killerformula]

Well a strip ride is really a different animal completely. Assuming this is a naturally aspirated motor and you're dealing with a high stall, you basically just want to build a motor that will stay in the greatest amount of power for the longest time. Since gearing is probably a factor, a high spinner may be an advantage. One thing to think about is that if you have a given set of heads that have a finite airflow potential at 28 inches, you would get there sooner with a few more cubes, and perhaps have to spend less money on "RPM" parts (stud girdles, main brace etc etc). The nice thing about an engine that's more forgiving on its RPM limit at the track, however, is that you can miss a shift or two and over rev so that your shift will dump you back into your power band at a more desirable RPM. You're a bracket racer, you know all this.

More cubes will basically just shift your power band lower. On the track it really doesn't matter as much, given that you can use a stall and slicks. With a little research you'll be able to see which motor is better for the money.

K

[Odium]

Killer, thanks for the reply. My big concern is consistancy. Since bracket racing is all about hitting your dial, is it really worth the extra money to build the 380? It'll make more power and over a broader range and I'm only assuming that the higher end parts will only aid in the consistancy of the motor. I haven't heard of or talked to anyone running 'built' 377s before so I'm not sure how they hold up to competitive racing. I have a lot of experience running stock stroke and mildly stroked motors so I know what to expect out of them but I'm curious and looking to try something new. Another concern is how a stock 509 cast block will hold up to 650HP and 8k at the track once a week. If I have to go aftermarket block, this motor won't see the light of day until at least the start of next season.

[sbchevfreak]

Assuming this is a naturally aspirated motor and you're dealing with a high stall,

A 377 is rarely used in an auto car, due to it's nature. As you know, smaller cubes intensify the stall speeds, and basically makes the stall rquirement go up. If the cam spec says 3500 stall (based on a 400), the 377 may require 4200+. As was said, combination is the key, and in the right trim, a 377 is dynamite.

I totally agree with Royce, this RPM limit on "stock" parts is somewhat ambiguous. With a little work, stock cranks/rods can withstand some fairly decent RPM/HP #'s. I personally had a 283 @.060, 350 crank and stock rods, that, with some deburring, peining, ect, turned 7500+ RPM regularly. Ran like that for me for two years in an 85 Z28, and the current owner also flogs the snot out of it in a shortbed p/u. 5 years, still thumping...... This engine walked all over 2 400's, a 383, and a 355. Displacement increases potential, but with some know how, a few bucks and hard work, smaller can beat it.

[Vehicle City Madman]

Well, let's settle this debate.

I have a 377SBC right now. For a street car, I prefer it over a 383 and would definitely build one again over a Std 400.

The 377 lacks in the low end grunt torque department. Which is actually fine for vehicles that lack in the traction department, like the S-10 I have it in.

That said, once your past 2000 RPMS you forget about the lack of low end torque as the RPMS fly by so fast you have trouble focusing on shifting gears. It runs the RPMS out so fast you swear Boost kicked in.

Mines set up @ 9.5:1 compression, runs factory heads ported and polished, nice overlapped cam with decent idle "numbers I will keep to myself" a Stealth intake manifold, 650 Holley and headers, runs on pump gas and makes over 400 HP.

This engine prefers to be closer to the rev limiter than near idle and makes me smile every time I start it up.

Engines are a matter of preference for the driver more than anything else.

If I had a 3300# Chevelle that would accommodate an L60-15 Race master, I would prefer the grunt of the 408 or 383. However, keeping an S-10 stuck to the ground is an issue, a major issue, so I prefer the 377.

If one wants to build a ridiculous engine there are many Race Fuel 377's running around well over 600HP.....

If I changed cams and installed a set of fast burn heads and changed intake and carb I could pick up and easy 50-75HP and run the RPMS out even better than now....

All it takes is money.