What's your Chevelle run in the 1/4 mile?
Big Block Heads
Thread Starter
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Big Block Heads
Looking at the aftermarket heads, many of them are advertised as having "Raised Exhaust Ports" with anywhere from .300 to .600 above stock. Will normal headers fit past the steering box and everything else with the port and header almost 3/8 higher than stock? How about the power steering pump rear bracket? Probably can slot the bolt hole to fit the 3/8, but for 5/8 it's going to take some real work.
Anyone have any input?
FWIW, I've got Hooker Sidemounts. I think there's enough between the primary tubes and the frame on the sides, but not sure.
Anyone have any input?
FWIW, I've got Hooker Sidemounts. I think there's enough between the primary tubes and the frame on the sides, but not sure.
Race Director
Joined: Dec 1999
Posts: 11,096
Likes: 990
From: Sierra Foothills CA
If you're not needing absolute max power you get can fairly close to that without dealing with raised ports. The Brodix Race Rites have great flow without raised ports. I don't have them because I needed small chamber heads- Edelbrock was my only aluminum choice at the time, and probably still is. If not for that I'd have the Brodix RRs.
http://www.brodix.com/heads/bbheads.php
http://www.brodix.com/heads/bbheads.php
Drifting
Joined: Oct 2005
Posts: 1,528
Likes: 148
From: East London/SW Essex UK
If you're not needing absolute max power you get can fairly close to that without dealing with raised ports. The Brodix Race Rites have great flow without raised ports. I don't have them because I needed small chamber heads- Edelbrock was my only aluminum choice at the time, and probably still is. If not for that I'd have the Brodix RRs.
http://www.brodix.com/heads/bbheads.php
http://www.brodix.com/heads/bbheads.php
Le Mans Master
Joined: Mar 2001
Posts: 6,240
Likes: 1,013
From: Watkinsville, GA and Glen Cove, NY
Tim, I am running the AFR's with a .375 raised exhaust port on my 502 and I had to modify 5 tubes of my Hooker Sidemounts to work. The main trouble is on the driver's side. I am still not happy with the alignment so I would say be prepared for some modification to your headers. It seems as if the main problem is not the "up" but the "out" caused by raising the port. I am thinking of getting a custom set made or the Stahl's made for the raised port heads when money permits.
Bill
Bill
Drifting
Joined: Nov 2002
Posts: 1,691
Likes: 206
From: Loveland, CO
I am installing the Brodix RR rectangular port heads on my L-71 as we speak. I am using original tripower intake and stock manifolds and didn't want to hassle with the raised ports either.
During me research, I discovered that the RR's do not flow as good on the exhaust as some of the competition. I addressed this by having Chris Straub grind me a hyd. roller with increased exhaust duration. He suggests about 14 degrees more on the exhaust than intake to rectify this issue.
Ralph
During me research, I discovered that the RR's do not flow as good on the exhaust as some of the competition. I addressed this by having Chris Straub grind me a hyd. roller with increased exhaust duration. He suggests about 14 degrees more on the exhaust than intake to rectify this issue.
Ralph
Race Director
Joined: Dec 1999
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From: Sierra Foothills CA
Instructor
Joined: Apr 2007
Posts: 142
Likes: 6
From: Indianapolis, Indiana
I haven't had this combo to the track yet. Currently I just cruise around on the street. I'm hoping to get it to the drag strip this summer. I know with a manual transmission it will be difficult to get the full potential out of this setup, but I would like to see high 10's and maybe with some practice and a little luck mid 10's would be nice.
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Thread Starter
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I've got the GM 1077 C-Port heads- the Edelbrocks flow about the same. Bottom line is there are several different heads out there and I'm looking. I really like the AFR's and the Dart Pro 1 series for flow numbers, but the raised ports are putting me off them.
I'm looking at pickling the LS-7 and building something that will make the same or more power- on pump gas. The only thing that's set in stone is it WILL be a big block.
I'm looking at pickling the LS-7 and building something that will make the same or more power- on pump gas. The only thing that's set in stone is it WILL be a big block.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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I've got Brodix 3xtra ovals now and used to run Brodix 2Xtra's. Both have exhaust ports raised .600". I found the 2-1/8" Hookers actually fit better by getting them closer to floorboards and raising them up. I did have to dimple the #3 tube by the stock steering box. When I added the Borgeson box I was able to remove the dimple and it all fit fine.
I cut off the PS bracket leg that comes around side of head and just use the bolts on the front. No issues even at 8000+ rpm.
JIM
I cut off the PS bracket leg that comes around side of head and just use the bolts on the front. No issues even at 8000+ rpm.
JIM
Thread Starter
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Jim are you running the sidemounts or undercar headers? When I get home I can look and see how much space I have between the frame and the tubes, I suspect there will be at least 3/4 of an inch. THe #3 tube on the ones I have came with a dimple and past that everything clears fine- it's just that I don't need the hassle of spending the bucks for the heads and then finding out the raised ports make the headers a hassle, which makes the p/s a hassle- you know the drill,,
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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Mine are undercar. I found the Hookers fit a LOT better on the right side than others because they route tubes away from idler arm whereas others just cook it.
There's quite a few folks using the AFR's with the .375" or so raised ports with no issues.
But as mentioned..the Brodix RR's are some great heads and can make killer power.The right cam can make it all work well.
The 555" I built for Doug Plette's "Bruiser" uses Dart 335's and sidemount headers. I don't remember any real issues that he mentioned...but he did install a Steeroids setup..so probably doesn't help much.
JIM
There's quite a few folks using the AFR's with the .375" or so raised ports with no issues.
But as mentioned..the Brodix RR's are some great heads and can make killer power.The right cam can make it all work well.
The 555" I built for Doug Plette's "Bruiser" uses Dart 335's and sidemount headers. I don't remember any real issues that he mentioned...but he did install a Steeroids setup..so probably doesn't help much.
JIM
Le Mans Master
Joined: May 2006
Posts: 9,993
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From: League City Tx
I've got the GM 1077 C-Port heads- the Edelbrocks flow about the same. Bottom line is there are several different heads out there and I'm looking. I really like the AFR's and the Dart Pro 1 series for flow numbers, but the raised ports are putting me off them.
I'm looking at pickling the LS-7 and building something that will make the same or more power- on pump gas. The only thing that's set in stone is it WILL be a big block.
I'm looking at pickling the LS-7 and building something that will make the same or more power- on pump gas. The only thing that's set in stone is it WILL be a big block.
The Brodix RR heads are also good but you may not see THAT much difference over your current GM perf aluminum heads..maybe 30hp or so...probably not worth the expense.
If I were gonna buy some new heads, I'd do the AFR 300 ovals...but have to fight the raised ports..
Melting Slicks
Joined: Nov 2003
Posts: 2,668
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From: St. Charles Mo
CI 5 & 8 Veteran
I'm in the beginning stages of an engine upgrade on my blue 69 roadster and following this post closely. My experience with Hooker side pipe headers on a 69 is that the clearance issue is not so much the frame, but up right behind the wheel well. The collector starts to interfere with the fiber glass body and rocker panel trim. On my 70 (aka Project Ramjet) I had to actually cut off some of the lower fiberglass panel behind the rocker panel trim as well as cutting a significant portion of the trim. That was back when I had hookers on it. On the 69, for some reason, I was able to get by with only trimming a very small sliver off the bottom of the rocker panel trim piece. I suspect going with the raised heads on the "Blue Angle" 69 upgrade will require even more cutting? NOT what I want to get into for the performance difference. Jury is still out but I'm looking at the Eldebrock Victor series aluminum heads?????? What do you guys think?
Bullshark
Bullshark