Friendly 377 vs 406 bet! - Chevelle Tech
Performance Our High Performance area

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 29 (permalink) Old Jun 23rd, 10, 11:47 PM Thread Starter
Tech Team
Tim
 
Join Date: Apr 2010
Location: Nor Cal
Posts: 798
Friendly 377 vs 406 bet!

So my friend/fabricator has been listening to me talk about the new motor I am getting so he has decided to build a sbc for his nova to beat me. Just friendly competition here so I am not going to be hurt TOO bad if he beats me... Eh who am I kidding. I REALLY want to beat this guy

My friend is building a 377 and I am building a 406 and here is some info on both


My 406
Forged bottom end
10.4 to 1 compression
Ported 200cc Brodix RaceRite heads (2.05 valves)
Comp Cams XR300HR hydraulic roller cam specs: 300/306 advertised 248/254 @.50 .562/.580 lift (proven to rev to 7000 before floating the valves with this setup and same builder)
Super Victor Intake
850dp carb

His 377
Forged bottom end
11.0 to 1 compression
Same ported 200cc Brodix RaceRite heads (2.05 valves)
Not exactly sure about the cam yet but he plans to spin this motor to 7500-8000rpm and its going to be a solid roller not over .600 lift.
Super Victor Intake
850dp carb

Okay so I am thinking that he will have trouble with the cam and heads situation. I might be wrong, but it seems like he would need a little larger intake runner than that to run that high of rpm's. They will probably be closer to 205 after the porting. I am looking more for power differences really. Sorry for not having an exact cam for his combo yet.

My car is a 68 chevelle that weighs 3500 with me in it. th400 tranny. Will experiment with converters and rearend gears to find the best combo.

His car is a 70 nova that weighs 3300 with him in it. th400 tranny. Will also find best combo.

Any thoughts on this? 1/4 mile times? fun factor? Both will get 225 shots as well later on. Is it smart for me to bet on this one?

1968 Chevelle - 3795# with driver
6.0 LSX with TSP 224R cam swap
S475 Turbo

16psi on 89 octane
10.95@81mph

Cageless
timvantol is offline  
Sponsored Links
Advertisement
 
post #2 of 29 (permalink) Old Jun 23rd, 10, 11:55 PM
Tech Team
 
Join Date: Apr 2010
Location: Minneapolis
Posts: 248
Re: Friendly 377 vs 406 bet!

It will really depend on what cam he has and who the better tuner is. He has a couple tenths on you already with the weight so your cubes won't mean much.
Winston Wolf is offline  
post #3 of 29 (permalink) Old Jun 23rd, 10, 11:58 PM
Guest
 
Join Date: Apr 2006
Posts: 3,965
Re: Friendly 377 vs 406 bet!

Quote:
Originally Posted by Winston Wolf View Post
It will really depend on what cam he has and who the better tuner is. He has a couple tenths on you already with the weight so your cubes won't mean much.
hate to be an echo but he pretty much covered it here.

just means you'll have to work extra hard getting it to leave and overcome the weight and possible power disadvantage.
curley8788 is offline  
post #4 of 29 (permalink) Old Jun 24th, 10, 12:15 AM
Senior Tech Team
Dave 383 now
 
Join Date: Dec 2006
Location: Ingersoll Ontario
Posts: 7,717
Re: Friendly 377 vs 406 bet!

If he's going to run a solid roller, he's going to smoke you.

Dave
Dave427 is offline  
post #5 of 29 (permalink) Old Jun 24th, 10, 12:21 AM Thread Starter
Tech Team
Tim
 
Join Date: Apr 2010
Location: Nor Cal
Posts: 798
Re: Friendly 377 vs 406 bet!

Both will be tuned by the same person actually. Both cars will leave well. I guess I am hoping that he will have way less bottom end torque with the 29 less cubic inches and the fact that he wants a high reving cam with lots of duration. He will be driving it quite a bit so he won't go crazy high on a torque converter and won't go any lower than 4.10 gears with a 26 inch tall tire.

1968 Chevelle - 3795# with driver
6.0 LSX with TSP 224R cam swap
S475 Turbo

16psi on 89 octane
10.95@81mph

Cageless
timvantol is offline  
post #6 of 29 (permalink) Old Jun 24th, 10, 12:23 AM
Senior Tech Team
Dave 383 now
 
Join Date: Dec 2006
Location: Ingersoll Ontario
Posts: 7,717
Re: Friendly 377 vs 406 bet!

If he wants to rev it to 7500+, he will need a 4000+ converter.

Dave
Dave427 is offline  
post #7 of 29 (permalink) Old Jun 24th, 10, 12:26 AM
Tech Team
 
Join Date: Jan 2005
Location: Alberta
Posts: 368
Re: Friendly 377 vs 406 bet!

What Dave says....X2,
especially if your buddy picks the right solid roller grind, it will run all over the HR grind!

93 Camaro backhalf car, 3100lbs SBC406 (tow truck motor) AED 850DP,super victor, AFR210 elim, Flat tops, UD Harold SR 243/249/112LSA, 1-3/4 custom headers, T-400, 4500 stall 4.30, best ET/MPH 10.30 at 129 mph (corrected), 10.57 at 126 at 3100 foot air. 1.39 - 60 ft. 91 octane pump gas.
47 years old, into my 5th decade of drag racing.
boldm is offline  
post #8 of 29 (permalink) Old Jun 24th, 10, 12:32 AM
Senior Tech Team
 
Join Date: Jan 2006
Location: SANDIEGO
Posts: 2,060
Re: Friendly 377 vs 406 bet!

if his engine makes shifts at 75-8000 rpm , that 377 is making alot of power ! your buddy will drive around you even if you do 60ft him !
Jason Snyder is offline  
post #9 of 29 (permalink) Old Jun 24th, 10, 2:10 AM
Senior Tech Team
Ken
 
Join Date: Sep 2005
Location: Missouri
Posts: 2,556
Re: Friendly 377 vs 406 bet!

Give that 406 a lot of SR cam, a lot of gear, and a lot of converter.

There are only three ways to make Horse Power. Increase your Brake Mean Effective Pressure, Reduce Friction losses, Raise your RPM.

As you can see, you only have one option, which is raising RPM. You will both make about the same BMEP and friction losses. So the winner must increase RPM range to make more HP. SO, you MUST be able to COMPETE with him with RPM's. If you don't also choose Solid Roller, you will be throwing away at least 5% power, and probably 10%.

You must be able to out RPM the competition. A HR won't do that. If you are building a steel rod engine, you must have them prepped for high RPM's. Talk to your builder about that. If you really want to beat the other guy, you are going to have to spend more money.

Not that the Comp HR cam is a bad choice, BUT it is not a race cam, just a hot street cam. I consider my SR 255/263@.050" /109 LSA cam to be middle/high end cam for a hot street 406. With 4400 Stall, it leaves well, but it's still more street than strip. (Can't believe I'm saying this. It is not a daily driver cam. If you pick the same cam, you won't be disappointed.) At least to my thinking. Mine is a stock crank, 4 bolt block. Nothing fancy. It also pulls well to 7000, but that's about it. If I were going racing, my engine wouldn't work. Built too cheap.

I've seen some very good running 377's, and for racing, that's a good deal. They are easier to build with aluminum rods so you can turn some good RPM's, like 8500 or so. The 400 blocks breath a little better, and they hold up well with shorter strokes. IMHO. (I don't like the bearing problem thing with 377's, but it doesn't seem to hurt when done right.)

kirkwoodken
406 SB, Original Bill Thomas '63 Rochester FI
AFR 210, Lunati 501C2LUN, 255/263@.050", .628"
10:1, TH400, 3.31's, 4400 SS

"Life is too short to not run a solid roller cam."
"Nothing is impossible; if you don't know what you're talking about."
Kirkwoodken
kirkwoodken is offline  
post #10 of 29 (permalink) Old Jun 24th, 10, 2:44 AM
Senior Tech Team
Brian
 
Join Date: Oct 2002
Location: Don't Blink PA!!
Posts: 3,733
Re: Friendly 377 vs 406 bet!

Hmmmm.....owning a 377 myself (a bit milder then the one above) I have had mine wound upto around 7300 rpms......with a 4 speed as well. I need to go auto to get this car quicker.

GREENHELL
377 sb, 5 speed, 4:11's
Line Loc Works!!
HeLLcamino,357 sb, 700R4 with lock up, 3:73's
The Bad Weather Beater
CHELKAMINO is offline  
post #11 of 29 (permalink) Old Jun 24th, 10, 8:00 AM
Lifetime Premium Member
Randy
 
Join Date: Feb 2006
Location: Loganville, GA
Posts: 977
Re: Friendly 377 vs 406 bet!

Quote:
Originally Posted by kirkwoodken View Post
Give that 406 a lot of SR cam, a lot of gear, and a lot of converter.

There are only three ways to make Horse Power. Increase your Brake Mean Effective Pressure, Reduce Friction losses, Raise your RPM.

As you can see, you only have one option, which is raising RPM. You will both make about the same BMEP and friction losses. So the winner must increase RPM range to make more HP. SO, you MUST be able to COMPETE with him with RPM's. If you don't also choose Solid Roller, you will be throwing away at least 5% power, and probably 10%.

You must be able to out RPM the competition. A HR won't do that. If you are building a steel rod engine, you must have them prepped for high RPM's. Talk to your builder about that. If you really want to beat the other guy, you are going to have to spend more money.

Not that the Comp HR cam is a bad choice, BUT it is not a race cam, just a hot street cam. I consider my SR 255/263@.050" /109 LSA cam to be middle/high end cam for a hot street 406. With 4400 Stall, it leaves well, but it's still more street than strip. (Can't believe I'm saying this. It is not a daily driver cam. If you pick the same cam, you won't be disappointed.) At least to my thinking. Mine is a stock crank, 4 bolt block. Nothing fancy. It also pulls well to 7000, but that's about it. If I were going racing, my engine wouldn't work. Built too cheap.

I've seen some very good running 377's, and for racing, that's a good deal. They are easier to build with aluminum rods so you can turn some good RPM's, like 8500 or so. The 400 blocks breath a little better, and they hold up well with shorter strokes. IMHO. (I don't like the bearing problem thing with 377's, but it doesn't seem to hurt when done right.)
Some good advice there. I have a 377 with Victor Jrs, and a Z/28 crossram, it loves to rev but still pulls great in the mid-range, better than I thought it would. Bearing problem is can be overcome, I have a 3.5" stroke Scat crank with 400 mains, no bearing spacers needed. Should be a good race, especially if you can hook up at the start.

81 Camaro - CP autox ride
03 Suburban 2500 8.1L - Tow Pig
92 Dakota V8 - DD
67 El Camino - Sold
Randy 67EC is offline  
post #12 of 29 (permalink) Old Jun 24th, 10, 8:45 AM
Senior Tech Team
Rick
 
Join Date: Nov 2006
Location: Langhorne, Pa
Posts: 3,654
Re: Friendly 377 vs 406 bet!

My wifes 377 prefers to be shifted at 6200 and goes through the traps at only 7400 rpm. Prior to her getting her license we kept lowering the shift point to keep the car 10.00 and it kept going faster each run that we lowered the shift point. I'm talking hundreths not anything overly signifigant.

It's my opinion that calling a 377 a high rpm combo is a myth. My experience with them show that they like a looser converter to get closer to the torque band but after that the difference really only comes doen to that 29 ci disadvantage, but some of that can be made up with cam, head, manifold and carb design.
Calculated Risk is offline  
post #13 of 29 (permalink) Old Jun 24th, 10, 10:42 AM Thread Starter
Tech Team
Tim
 
Join Date: Apr 2010
Location: Nor Cal
Posts: 798
Re: Friendly 377 vs 406 bet!

Talked to him this morning and he has decided to change cams for more street driving. He is going to be running a 3500 stall with 4.11 gears so he wants to run either this cam

Comp Cams XR292R Advertised duration 292/297 254/260 @.50 582/588 lift 110 lobe seperation.
RPM range 3200-7200

Or this cam

Comp Cams XR286R Advertised duration 286/292 248/254 @.50 576/582 lift 110 lobe seperation.
RPM range 3000-7000

1968 Chevelle - 3795# with driver
6.0 LSX with TSP 224R cam swap
S475 Turbo

16psi on 89 octane
10.95@81mph

Cageless
timvantol is offline  
post #14 of 29 (permalink) Old Jun 24th, 10, 11:45 AM
Tech Team
Lynn
 
Join Date: Feb 2006
Location: Macomb, IL
Posts: 53
Re: Friendly 377 vs 406 bet!

And a lot of it will come down to the individual driver as well. Are you running beehive valve springs and a rev kit with those hydraulic roller lifters? Otherwise, I don't know how you will keep from floating the valves at 6500 rpm much less 7000 rpm.

-Lynn


There is no 12 step program for stupid.

http://photo.net/photodb/folder?folder_id=506187
rumrumm is offline  
post #15 of 29 (permalink) Old Jun 24th, 10, 1:23 PM
Senior Tech Team
Bobby
 
Join Date: Nov 2008
Location: Va.
Posts: 1,729
Re: Friendly 377 vs 406 bet!

probably too late in the game, but your combo could use more cylinder head. Especially if you plan to utilize the Super Victor intake.

-Bobby-
1965 SS 331 Muncie
Lilracr is offline  
Sponsored Links
Advertisement
 
Reply
Gear in this thread - Powered by O'Reilly Auto Parts

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevelle Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address. Note, you will be sent a confirmation request to this address.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome