Who runs a 427 BBC? Enough or go to 454? [Archive] - Chevelle Tech

: Who runs a 427 BBC? Enough or go to 454?


fatmattbbc
Oct 10th, 03, 8:20 PM
My nephew wants to go Rat in his "71". Needs a crank. He is mystified by the "427" legend and history. I told him to go with a 4.0 stroke crank, just because of more cubes, and better piston selection. I feel the seat of pants feel he will like better. The car is for 90% street and 10% strip. He has a M-21, and factory Rect. port heads, and 4.11 rear. He also wants a Hyd. roller. Other than more revs from the 427 I can not see why he would want less cubes. Maybe if he reads opinions from other people he can make up his mind. Thanks.

Mike Feudo
Oct 10th, 03, 8:39 PM
Go as big as you can. In a 2 ton car you need all the torque you can get especially with a 2.20 low trans.

10secBu
Oct 10th, 03, 8:43 PM
I'd go with a 4" stroke crank.

Although my 427 based BBC works well for what it is, I still wish it was a 454.

Redrum
Oct 10th, 03, 8:56 PM
If you need to buy a crank go with the 4.25 stroke and really have some fun. Tell him to put the "427" badges on everything and only he will know why it rus so good.... Heck I went with the "396" badges all over my car.

TriplblackL78
Oct 10th, 03, 10:05 PM
i have always run 454s but the next engine i build IS going to be a 427. the hot trend now is big bore short stroke, you get alot more for your money that way and a much more efficient combination. you put that 3.75 crank in there and bore it+.060 or +.100 and you have everything if not more than a 454 would be.and on top of it the car has a stick, maybe with an auto. you could go 454 that might make some sense.
john graemlins/thumbsup.gif

Darracq
Oct 10th, 03, 10:12 PM
The big bore short stroke is for power adder cars that need to kill some low end and rev high. NOt a heavy car.

JIM
Oct 10th, 03, 10:23 PM
sniff, sniff, I feel so all alone here :(

TriplblackL78
Oct 10th, 03, 10:24 PM
well isn't that what you want with a 2 ton car running on a 9 inch tire, kill the low end? :D

ddeennis
Oct 10th, 03, 10:24 PM
i would say that there is not alot of different performance wise between the two motors in stock to mild form......i dont think any one here would be able to tell the difference if they was told to drive this car and guess which is it....is it a 427 or 454....just by the feel of the pants mind you.....some of you will get lucky and others would be off.... build according to your budget and what you have to work with......

i know alot of you would argue the point of more cubes but who is really going to know difference......im sure alot of you would drive my race car and would believe it to be a 454 at least because how fast it is....but what would you say if i told you it was a 396 and truely was....like i said many of you would not know the difference build what makes YOU happy not what others think you should build....besides who going to be driving it more.........

Bomber '67
Oct 10th, 03, 10:35 PM
...when you ask an opinion...multiple answers you will get.

If he wants to build a 427 there will be no harm done, so let him do it. Too bad he wants a hydraulic roller - he'll miss out on the solid flat tappet/solid roller rpm capability of the 427. A 427 at 7,000+ rpm has a song of its own. Have him sell the rectangular port heads and get ovals instead. I cannot think of any sub 6,500 rpm 427 that would need the port volume of the rectangular port heads.

Thomas

TriplblackL78
Oct 10th, 03, 10:36 PM
kinda the point i was trying to make,my friends 68 camaro with a 447 (100 over427) and my car 69 chevelle with a 468, both weighing the same, his went 10.16 and mine went 10.17 on the same day, but he probably had only 2500.00 in his motor and i had around 4grand in mine. and who is driving more? the nephew who is mystified with the 427s, right?
graemlins/beers.gif

fatmattbbc
Oct 10th, 03, 11:26 PM
That is two things I tried to explain to him, 1.) He be better off with 049 or 781 large oval ports for the street and 2.) That a solid flat tappet would be a better choice than a hyd. roller, a solid roller even better. He reads that GM put the Rect. heads on 396's, 427's, and the 454, and thinks that is what is needed for a fast car. But I told him that in the long run it is his money and car and having fun is the most important thing.

68chevelle533
Oct 11th, 03, 12:14 AM
Years ago I had a 396 with basicly the same parts as my friends 454, both in 70 chevelles. I saw alot of his tail lights. The seat of the pants difference was even more dramatic. A 427 is a great engine and people go fast with them, its just hard to argue with cubic inches.

smittyocat
Oct 11th, 03, 12:22 AM
I have run a .060 over 396 for years with great success the motor is a 10.5:1 closed chamber oval port engine with an 850 DP,HEI, Isky 292/590 cam, steel roller tip rockers,torker intake manifold. with a TH400 and 3500 conv. In my 69 Malibu full body 3,600 lb car with 4:56 gears it has run consistent 11.60's not bad for a "baby rat" :D

68chevelle533
Oct 11th, 03, 12:46 AM
Open mouth insert foot graemlins/clonk.gif Didn't mean to step on any toes. I grew up in the 396 era of the early 70s. They were very popular back then. Had to build one, and I beat my share of 454s with it. But didn't beat too many with similiar setups.

coop
Oct 11th, 03, 11:36 AM
Since when did the trend go over to big bore short stroke motors. I seem to be seeing a lot of stroker setups lately: 502,540,632. I would have to say the trend is to use as much stroke as you can and build around that.
"No replacement for displacement"

10secBu
Oct 11th, 03, 12:50 PM
Originally posted by coop:
Since when did the trend go over to big bore short stroke motors. I seem to be seeing a lot of stroker setups lately: 502,540,632. I would have to say the trend is to use as much stroke as you can and build around that.
"No replacement for displacement" I guess you don't follow any of the fastest street type cars series? The trend in tire limited classes is to use a large bore which unshrouds the valves for good air flow through the heads, yet keep stroke short which limits torque and makes the engine more of a high rpm mill.

The problem I see in the street/strip crowd is the use of 496 based engine combinations with very limited suspension mods. This may make a strong street runner, but most of the times these guys have real issues in hooking at the track.

THORSS70
Oct 11th, 03, 1:55 PM
Originally posted by Epistuff:
sniff, sniff, I feel so all alone here :( Don't feel bad, I have had a 427 for years and it does quite well. Here is a hug for ya' *hug*

slpin
Oct 11th, 03, 2:33 PM
i say make the 427. if he likes it - build it. it is a big block, it will make power either way graemlins/thumbsup.gif

dukejoh
Oct 11th, 03, 3:29 PM
I hope your nephew is an older nephew....I can remember my first couple of years driving and I am glad my dad made me get rid of my first chevelle. I did enough damage to my driving record(and others property) with a inline 6 cylinder ford truck. But whether a 427 or a 454, it will still bring a smile. smile.gif
Caleb

TriplblackL78
Oct 11th, 03, 7:31 PM
Originally posted by coop:
Since when did the trend go over to big bore short stroke motors. I seem to be seeing a lot of stroker setups lately: 502,540,632. I would have to say the trend is to use as much stroke as you can and build around that.
"No replacement for displacement" Isn't a 502 a big bore 454? it has a 4.00 stoke right? i guess the trend(big bore short stroke)is for guys who want to go fast consistently, not once every blue moon. graemlins/waving.gif

slpin
Oct 11th, 03, 7:47 PM
Originally posted by TriplblackL78:
</font><blockquote>quote:</font><hr />Originally posted by coop:
Since when did the trend go over to big bore short stroke motors. I seem to be seeing a lot of stroker setups lately: 502,540,632. I would have to say the trend is to use as much stroke as you can and build around that.
"No replacement for displacement" Isn't a 502 a big bore 454? it has a 4.00 stoke right? i guess the trend(big bore short stroke)is for guys who want to go fast consistently, not once every blue moon. graemlins/waving.gif </font>[/QUOTE]yup, 4.47 and 4 stroke, big bore, short stroke. same with 540, 4.5 bore, 4.25 stroke.... still more bore. 572... 4.56/4.375 - more bore, less stroke

sure dont look like they use as much stroke as they can, and certainly more bore than stroke

coop
Oct 11th, 03, 10:01 PM
Hey I think you guys need to read this post from the beginning again 90% street 10% strip. I wouldn't build a car that is setup to compete in a special tire limited race class that your not competing in anyway, and slpin if you read what you yourself posted you will realize that you are confirming what I already said :
502ci=4.00 stroke
540ci=4.25 stroke
572ci=4.375 stroke
seems to me that each motor you mentioned has more and more stroke. I rest my case.

10secBu
Oct 11th, 03, 10:14 PM
Originally posted by coop:
Hey I think you guys need to read this post from the beginning again 90% street 10% strip. I wouldn't build a car that is setup to compete in a special tire limited race class that your not competing in anyway, and slpin if you read what you yourself posted you will realize that you are confirming what I already said :
502ci=4.00 stroke
540ci=4.25 stroke
572ci=4.375 stroke
seems to me that each motor you mentioned has more and more stroke. I rest my case. OK fine, 90% street...then tell me what the added stroke does for you on a 90% duty STREET CAR???

My lil 3.600" stroke bbc will smoke the tires (drag radials) at will, so the added stroke simply makes more of a tire burner. What's the purpose of that? short stroke, long stroke...both will be of little use on the street with true street tires.

If such a car is truly a true 90% street car, then quick ET's are obviously of very low priority and ANY bbc and ANY stroke combination will suffice...heck even a small block will due fine...say a 383 or 406.

TriplblackL78
Oct 11th, 03, 10:25 PM
i can think of 2 real good places for stroker motors, tractor pulls and boats. if your 90% street i think you will have 90% spin when you punch the throttle with the big stroke :eek:

go cubs

Mike Feudo
Oct 11th, 03, 10:40 PM
Am I missing something or didn't we have wars about oval port heads vrs. big port heads. One of my reasons for using big ports on 427s and bigger was the loss of low speed torque so you could actually use the power. Now I see everyone has decided that you can't use low speed torque so you shouldn't build a big motor. He has big port heads with a decent cam a 454 will work just fine.

10secBu
Oct 11th, 03, 10:49 PM
Originally posted by Mike Feudo:
Am I missing something or didn't we have wars about oval port heads vrs. big port heads. One of my reasons for using big ports on 427s and bigger was the loss of low speed torque so you could actually use the power. Now I see everyone has decided that you can't use low speed torque so you shouldn't build a big motor. He has big port heads with a decent cam a 454 will work just fine. The street and track are two different worlds Mike...IMO, it doesn't matter squat what you use on a 90% street car...ain't gonna hook on street tires anyway. Now true street/strip, that's a different story.

Bomber '67
Oct 11th, 03, 10:50 PM
...like I expected, this is one of those posts that has both sides like two ships passing in the middle of the night - neither one seeing the other.

Anything can be made to have good or bad results performance wise - getting slightly off subject there are "street" 355's running 9's. It all depends on how you want to define street. I'll guess that most people would not view a small big block 10 second Malibu as much of a street car.

It is impossible to tell youth how to avoid the mistakes they are determined to make - let him have his mild cam big port 427. His education will start the moment he gets spanked by a well set up oval port 396 (or some overbore variation).

Whatever he chooses, it will be a street radial burnout star for him and all his buddies.

Thomas

427L88
Oct 11th, 03, 11:22 PM
Originally posted by 68chevelle533:
Open mouth insert foot graemlins/clonk.gif Didn't mean to step on any toes. I grew up in the 396 era of the early 70s. They were very popular back then. Had to build one, and I beat my share of 454s with it. But didn't beat too many with similiar setups. ABSO FRIGGIN LUTELY !

And Mike, you're wrong about " just throw 427 badges on it" and such. If you run it at the track, you, and every one else will know, if its a 427. Fast 427s have to run revs to make the power. Touching 7000. IMHO, of course.

You want a 427 to run low 12's , high 11's, you need to run it up a bit. It won't hurt it none.

fatmattbbc, I absolutley concur with the advice you gave your bud. graemlins/thumbsup.gif They deserve, at the least, a solid flat tapppet. Really like Harold's 276/84 grind.

Picked up a set of 049s today. Chambers look like tadpole ponds. Gotta move some iron off these. "lighten" them ;) and get the chambers a reasonable size.

John ( coop) , no doubt. I got absolutely ( that word again) got SPANKED today by one of those big inch street motors. But if the goal is 12's, high 11's , a 427 will do it fine.

Jim, you are not alone! graemlins/beers.gif I'm right here with you bud! Had a blast with my 427 today. Ran about 600 miles to and from a show, made a 1/4 mile pass, and hung out with some cool dudes.

I love that figgin motor. 3400 cruise rpm. It wants to keep on running AFTER running for 3 hours straight. Meaning you come off the highway after a long pull, and its at it best. Real crisp! Also meaning if you are going to be running 4.10's, keep your piston speed down a bit with the short stroke.

Yes, it's true. I LOVE my 427! graemlins/hurray.gif

crowenate
Oct 11th, 03, 11:41 PM
Personally I like a 427 better,I am building a 454 just because i got a heck of a deal on it,but if i had a chance to trade for a 427 id do it in a heart beat.

pdq67
Oct 12th, 03, 1:30 AM
I never thought about the 1/8" over, 4.375" b x 3.76" stroke 452 motor before...

I figure with a good strong and balanced rotating ass'y, it should run like a BIG 327!!!

Make her about 10.5 to 1 CR. Put a set of 290cc rect's on it with 2.25"/1.94" valves, a good 290/250 or so solid cam and an old 830 cfm Holley carb. on it along with a set of 1.875" four tube, long headers and hold on....

Should more then run with an old 12 to 1, L-88 or true LS-7, 454 motor any day...

pdq67

slpin
Oct 12th, 03, 1:32 AM
Originally posted by coop:
Hey I think you guys need to read this post from the beginning again 90% street 10% strip. I wouldn't build a car that is setup to compete in a special tire limited race class that your not competing in anyway, and slpin if you read what you yourself posted you will realize that you are confirming what I already said :
502ci=4.00 stroke
540ci=4.25 stroke
572ci=4.375 stroke
seems to me that each motor you mentioned has more and more stroke. I rest my case. edited out... man... just forget it... you are not open to opinions and will only have it your way - be it the right way or wrong way :rolleyes:

427L88
Oct 12th, 03, 8:34 AM
Hey, fwiw, and this is speculation, I have a 439 ci ) +060 427) that should run 11.7s in a auto/high stall config.( by a good racers prognostication) Not bad. 14mpg on the highway as well. Bring on the untuned ZZ502s!

coop
Oct 12th, 03, 9:11 AM
Hey I never said anything about a RIGHT way or a WRONG way.All I was pointing out is that I don't see a TREND going to short stroke motors I see more and more people building stroker setups than ever before. I am not saying that a short stroke motor want run awesome(I have a 396 myself) I just stated that I see a lot of stroked motors being built that I didn't see being built 5 to 10 years ago. Build whatever you want, slpin I don't know why you seem to take this so personel but get over it! :confused:

fatmattbbc
Oct 12th, 03, 3:10 PM
Thank you for all the replies smile.gif graemlins/beers.gif . My nephew decided on what he originally wanted a 427. He said he bought a used GM steel 3.76 crank locally for $150. The gentleman has receipts for it being hot tanked, magnafluxed, and it had to be turned .10 under on both main and rods. The guy he bought it from just recently bought a ZZ502 crate motor. He will stick with the Rect. port heads because he can not afford to buy other heads. As far as him wanting a Hyd. Roller cam, I suggested to him he might want to price the lifters and cam. He did. He will not be using a Hyd. Roller. He took my advice and will use a solid flat tappet, which I feel will be best with a 427 and a 4.11 rear. He is a good kid mature for his age 23, just green about motors. Like I told him before MAIN thing is having fun and learning as you go along. graemlins/beers.gif

427L88
Oct 12th, 03, 3:17 PM
Matt, I would seriously urge him to consider Harold's 276/84 or similar grind! If it's occasional use and can run on 93, give it all of 10-1 under iron. 10.5 under alums.

fatmattbbc
Oct 12th, 03, 8:05 PM
Thanks Gene. Here in S.E. Pa. we got Sunoco 94 octane, so if he keeps the DCR within a safe range one of Harold's grinds would work nice. I was thinking maybe on a 108 lobe seperation, since he is running a stick box. I found Harold's new # and ext. at Lunati on this site. I will give it to my nephew and he can talk to Harold. I think he just might learn something after talking to him. Regards, Matt. graemlins/beers.gif

427L88
Oct 12th, 03, 8:16 PM
The only thing about the 108 and a stick box I notice, is that is makes easy 1st gear stoplight letoffs harder, especially with that 2.20. Might want to stick with 110, or at least consider that when making your final choice. It isnt like a 3500 stall converter on the street. Noticed a big difference between 114 and 110 lsa in that regard, as you might expect.
Think I'm finding it a smidge easier to launch a street stick car with a wider lsa. I think. Yet to be discovered.

fatmattbbc
Oct 12th, 03, 8:34 PM
Looks like I learned something. I will have him mention to Harold about having it on a 112 or 114 LSA. Thanks. :D

jakeshoe
Oct 12th, 03, 9:22 PM
Well...
i've had a few BBC's.
402, 427, 454 all of them...

So far my favorite streetable combo is my current 427.

It runs as well on the street with a milder cam, less intake, etc.. as the 454 did.

The 454 WOULD ET better but it was in a slightly lighter car, had more cam, same basic heads, better induction system, etc..
But not by enough to really matter on a driver.

My MILD 427 will run a high 12, idles like a stock 350hp 396, gets driven daily, turns 6000 rpm almost daily, and is WORN OUT.

Still runs like a striped ape.

I wouldn't hesitate to build another one, and when the 505cid stroker goes in my Chevelle, the 427 will get freshened and saved.
I'll never sell it as I have enjoyed it TOO much.
I'll freshen it, and run it again, same combo as now.


One thing to add since you are in the market for a solid flat tappet.
I had one ground for my 505 and went roller so this one is for sale.
236/242 @.050 on a 112 LSA
If interested email me.
$90 shipped
Would work well in a 427, even with the rectanglular heads.

Also might tell you nephew the rect. may bring enough for him to sell them and buy a set of decent ovals...

427L88
Oct 12th, 03, 9:39 PM
I'll simply add, that I went from a 114 to a 110lsa ( darn glad I didn't go tighter), and sometimes, for daily 'type' driving, wish I had a 112.

Naw, the rowdy 110 peaks when it hits the finish line at 117+ mph! Too cool!

But there is something to be said for the streetability of a 112 lsa cam to be sure.

TronDD
Oct 12th, 03, 9:51 PM
What is the LSA changing to make it harder to drive a stick car?

Tim.

427L88
Oct 12th, 03, 10:04 PM
Easy off idle take offs for daily driving.

TronDD
Oct 13th, 03, 2:20 AM
Yes, but why is it harder to take off from idle with a narrow LSA? What is the LSA changing? Is a narrower LSA removing lower RPM torque?

Tim.

chevywidow
Oct 13th, 03, 6:52 AM
Seems a bit late to jump aboard but here I go anyway. I run the LS7 block @ +.060" with a 3.76" forged crank and now alum roval. Set a new personal best yesterday and finished in the top ten club for the Pro ranks. First year rookie. 7.58 1/8 mile at 93.4 with XE284 flat hyd and 750 carb. Oh ya, put the steel rims on with dog dish caps. Got thru tech on Sat. but not yesterday. Back to topic, build whats heart felt. You can always chalk it up to experience. The only thing I'd do different is to put a solid cam in her, cause it just wants to rev all day. I'm with ya Gene. Take care all, Tony A. graemlins/waving.gif

427L88
Oct 13th, 03, 7:05 AM
NICE TONY!

Tim, this isn't gospel but, my thoughts are the wider LSA cams have a wider powerband, come on earlier adn off later. Its the come on earlier part that helps that low speed off idle takeoff.

Having said that, after my first track result, I wouldn't change a thing. Harold's cam ROCKS a lil 427! BIG POWER! I thought he said once his cams don't mind wider LSA's. The 276/84 on a 112 might be a nice solution.

Oh,. and check out the new times and mph! Times are solid with a soft 60'. Almost won, heads up, again a 509 Camaro. 15 mpg all the way home. Rect ports to boot!

SPIN "EM UP GENTLEMEN!!!!!!

Matt, my DCR cal's to 8.5 with alums. 10.51:1 static. I;d shoot for 10.2 with iron rect port heads, just to be safe. Using 94 Sunoco mostly.

Do try and get one of the 276/84 sticks from harold and DEFINTELY phase it +6 advanced. I don;t know why, but it works MINT like that, as Harold said it would, getting max port velocity out of the rect heads, as he put it.

at almost 119 mph , that lil 439" is doing something right.