Team Camaro Tech banner
Cancel
Create thread New Garage Forums

400 SBC COMPRESSION RATIO

Jump to Latest
21 - 40 of 41 Posts
#21 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by Lonnie67:
So if I build my 383 with iron heads and 6.5:1 compression, it will run the same? How about 8:1,

<HR></BLOCKQUOTE>

So does that mean you're not going to answer my question?

I don't question that small or big BSE runs as claimed, I never said my aluminum heads are better than ported BSE iron, if you'd actually read my posts, you'd know that. You can't compare 170cc to 200cc ports. I think a comparison between SR's and RPM's is valid.

Just the porting on my Bowtie heads cost $600 by a reputable head porter 17 years ago. I know it is more now, that is my point.

Exactly what BS do you "see" through? I'm not asking these questions to be a jerk, I really want to know.

Lonnie



------------------
67 Camaro, strip/street 410sb 11.63 @117.6
67 Camaro, daily driver 388 12.07 @112
website
SHUT UP AND RACE!
 
#22 ·
Thanks Tracy
Image
I was thinking it was HRM for some reason - maybe thats why I couldn't find it.

CNC - 3 points compression change alone is worth roughly 56 HP according to DD2k when going from 9:1 to 12:1 on a run-of-the-mill 400 HP 383 small block. Now who's exaggerating?
 
#24 ·
Hmm, We could ask the Big guy himself, but Oh wait he got Kicked off the board!
10.85 with a 1.45 sixty foot is not exaggerating,
I've yet to see a comparible Aluminum headed combo do that! With exception to 40 coupe's combo (That's nearing it!), but his is a stroker.
So yeah maybe there is a difference of about 56HP when compairing to of the same combos with the difference being the cylinder heads.
Just becuase i havent seen Any 10:1 355ci small blocks with a flat tappet cam in the high 10's with a 1.45 60ft time.


Funny that they never figured out what a true comparison is, compaire to similar heads, where one has the CHAMBERS WORKED!
Why did they Work the IRON chambers to make everything ACTUALLY EQUAL.

407 at 5,600 rpm It took them 220cc heads, a Solid ROLLER cam and 383 cubic inches to make 407HP? Seems pretty lame to me!
Sure now that they didnt do any tweaking to the aluminum Engine that they Forgot to do to the other engine???
I guess we'll never know,
What i do know is that the Iron headed combo's that I know of Work, they Work Well and they're streetable, so I've done and said my Peice
Image

I guess its for you guys to decided!
 
#25 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by CamaroNOTcamero:
Hmm, We could ask the Big guy himself, but Oh wait he got Kicked off the board!
10.85 with a 1.45 sixty foot is not exaggerating,
I've yet to see a comparible Aluminum headed combo do that! With exception to 40 coupe's combo (That's nearing it!), but his is a stroker.
So yeah maybe there is a difference of about 56HP when compairing to of the same combos with the difference being the cylinder heads.
Just becuase i havent seen Any 10:1 355ci small blocks with a flat tappet cam in the high 10's with a 1.45 60ft time.


Funny that they never figured out what a true comparison is, compaire to similar heads, where one has the CHAMBERS WORKED!
Why did they Work the IRON chambers to make everything ACTUALLY EQUAL.

407 at 5,600 rpm It took them 220cc heads, a Solid ROLLER cam and 383 cubic inches to make 407HP? Seems pretty lame to me!
Sure now that they didnt do any tweaking to the aluminum Engine that they Forgot to do to the other engine???
I guess we'll never know,
What i do know is that the Iron headed combo's that I know of Work, they Work Well and they're streetable, so I've done and said my Peice
Image

I guess its for you guys to decided!<HR></BLOCKQUOTE>

Just admit you are wrong for once and get on with life. CNC chambers ARE NOT worth 56 HP over as-cast, iron heads ARE NOT worth 56 HP over aluminum and you know it. The aluminum vs iron comparison done in CHP is valid testing so don't try to discredit it just because it doesn't support your theory. Instead maybe you could produce some other test that supports your idea. Maybe I should get pistons with the ceramic coating to reflect heat and make another 56 HP.
Image


There's no doubt Ed has put together some good combos. BUT it's the COMBO (including the chassis) that works, and to say its the iron heads does a disservice to Ed's hard work finding and tweeking a combo that works together. I'm sure Ed could build an aluminum head combo just as good as his current iron head small block if he wanted.

BTW Any particular reason you insist on arguing so much? I'm sick of your argumentative posts and wish you'd quit bragging about someone else's accomplishments. You ain't Ed.

ps. What does your combo run?
 
#26 ·
You know, one thing that people seem to overlook when comparing heads is that weak ports CAN be crutched with a GOOD cam pick!!

You can add duration and/or lift to even out flow rates intake to exhaust if so desired so if you come across a low priced bargain in a set of not the best/newest-high-zoot heads then take advantage of the low price deal and tune them using a good cam pick!!! pdq67

PS., I think you can coat the water passages of aluminum heads with baked on waterglass, (i.e., sodium silicate), to keep them from bleeding too much tewmperature out of the chambers, but may be off here???

Just coat, harden and try and coat again until you get what you want!
 
#27 ·
CNC, remember why Ed got kicked off the board? He started flame wars, I think you may be headed in the same direction!
 
Save
Reply Quote Like Like
#28 ·
Ok dude, this time why dont YOU prove that your right?
I want some numbers.
BTW, my appologies for not making enough money to quickly build up my engine. But then again that gives me plenty of time to Think things out.
Eric, Ed's not doing Himself a disservice by using Iron Heads, IMO. I think (wait i KNOW) they work well!

Argue all you like, that "comparison" dyno pull doesnt mean a thing! One pair has Worked chambers, PERIOD!
Eric, i really didnt want to make this personal, so i'm going to stop posting on this post.
I'll Agree to disagree.
 
#29 ·
The power figures in that article are pretty lame, but they are just as lame for the iron heads though. Someone missed that part I guess. It just supports what I said earlier, port design is more important.

If anyone can tell me where to buy new complete iron heads for $900 that will give me 56 more HP, I'll go buy them tomorrow.



------------------
67 Camaro, strip/street 410sb 11.63 @117.6
67 Camaro, daily driver 388 12.07 @112
website
SHUT UP AND RACE!
 
#31 ·
Guys,
So, is the conclusion that iron heads will make slightly more power given the same circumstances?
I have a 406 with a set of Turbo GM heads that have been heavily ported and polished with 2.08, 1.66 valves. Would I see a huge increase with say a set of AFR 210's?
Thanks,
Donnie
 
Save
Reply Quote Like Like
#33 ·
CNC - What's up with the agressive approach? I'm not going to comment on alum vrs iron or rect vrs oval, I have opinions but for now that's not the issue. The issue is the way your forcing your (dare I say Ed's) views down peoples throats. Say what you have to say, post it and let others decide for themselves. This actually goes for everyone here as it takes 2 to tango.

CNC you are a rookie, (that's not a slur or put down, it's how folks get started) your posting history is here for all to see. One of the things you are doing goes against the grain of everything your mentor stands for. That is speaking from personal experience and not second hand information.

Let's move forward and not regress to some places we've been in the past!!
 
#36 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by CamaroJSU:
Litte change of pace, with the proper set up is 10.2:1 in a 400 to much compression for Nos. Maybe anything under a 100 shot. Just your thoughts. Thanks <HR></BLOCKQUOTE>

Nope...I plan to have 10.5:1 with my 406, and plan to spray 125 shot......

------------------
383 Speed-O-Motive stroker kit with Holley 750DP, RPM intake,MSD6a box,World Products Sportsman II heads, ported and polished with 2.02/1.60 valves,64cc,TRW forged pistons with 10.7:1 compression, Comp Magnum 294s solid cam,Crane pushrods, Comp Cam 1.6 full roller rockers,MSD Pro Billet,ATI damper, 40 series Flowmasters, 4.11 gears with TH350 and Hughes 3000 stall.
 
Save
Reply Quote Like Like
#37 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by 1968camaro123:
Guys,
So, is the conclusion that iron heads will make slightly more power given the same circumstances?
I have a 406 with a set of Turbo GM heads that have been heavily ported and polished with 2.08, 1.66 valves. Would I see a huge increase with say a set of AFR 210's?
Thanks,
Donnie<HR></BLOCKQUOTE>
have you cc'd or flowed those heads of your's? like stated above, it does matter what your combo is, but i will tell you a 406 loves a fairly large cam, and good flowing, bigger runner heads, such as those afr 210's. remember, those are big block cubic inches. and as far as 10.5:1 being too much compression for nitrous, no way. i know several guys that have well in excess of 11:1 w/ 406's that run 200-250 horse shots with no problem. just make darn sure your fuel system is up to it. heck, i built my motor for nitrous, not planning on regular use but wanted the option, and its 11.5:1. and i'm not worried at all. hope that helps
 
#38 ·
Lonnie,
It's a 406 small block with the above heads(steam holes drilled), comp solid cam .550 lift. 10.5 to 1 CR, victor jr. intake, holley 800 double pumper, forged internals, shot peened rods. Anything else just ask...I'm also running a 200 shot. It's in an el camino right now that runs 11.70's on the motor and and about 10.6's on the bottle so that'll be about 11.5's in the camaro and 10.4ish on the spray.
Thanks,
Donnie
 
Save
Reply Quote Like Like
#39 ·
Hi I seen your engine combo in a prior post and am your neighbor. Yeah no air up here and was wondering if your 750 carb was jetted down for elevation and or if youre running a VS carb. I have a 670 on mine and was thinking of bigger? Thanks.
 
#40 ·
Chuck William said:
Hi I seen your engine combo in a prior post and am your neighbor. Yeah no air up here and was wondering if your 750 carb was jetted down for elevation and or if youre running a VS carb. I have a 670 on mine and was thinking of bigger? Thanks.
Click to expand...
If you look at the dates, this all happened 18yrs ago.
He probably runs an LS by now.
 
21 - 40 of 41 Posts
About this Discussion
40 Replies
20 Participants
Last post:
scblucam
Team Camaro Tech
posts
2.4M
members
90K
Since
1998
A forum community dedicated to 1st generation Chevy Camaros owners and enthusiasts. Come join the discussion about performance, builds, restoration, modifications, classifieds, troubleshooting, reviews, and more!
Full Forum Listing
Explore Our Forums
Bench Racing Engine Body Shop Performance Brakes, Suspension & Steering