BB Rec Port Intake
Thread Starter
Intermediate
Joined: Mar 2002
Posts: 45
Likes: 0
From: Ashville AL
BB Rec Port Intake
I am currently running a Torquer II intake on iron oval port heads with a Barry Grant carb. With a little modification of the air cleaner this fits under my stock BB hood. I want to go with some aluminum rec port heads. What kind of intake (if any) will fit under my hood using the same carb with minimal modification? All rec ports that I have found are all high rise(for a reason I am sure), but I am willing to sacrifice some performance for fit. Anyone know of a current or old production alum intake that will work. Part #'s would be appreciated. I have an old 163 cast intake, but do not want to cut on it nor do I feel like I could cut it enough to fit.
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 2
From: New Zealand
I think your only choice is an LS6 manifold.....part number 3963569....
They are not hard to find.....A used one that needs some work will cost about $300...I followed a really nice one on Ebay that sold for just over $500.....have heard NOS going for $600 to $1000.....Paragon have a couple but they want $750 each (don't know the condition)....have seen them advertised in Hemmings as well....
I bought a reproduction LS6 intake from ThePartsPlaceInc on Ebay....they also have a website....
No problems with the repro manifold, carb & gasket surfaces straight & true......it comes with a heat shield (although mine had to be modified for the Gen 6 454HO crate engine) and it fits under the stock BB hood.....
Oh yeah....you'll need a carb spacer
Hope this helps
They are not hard to find.....A used one that needs some work will cost about $300...I followed a really nice one on Ebay that sold for just over $500.....have heard NOS going for $600 to $1000.....Paragon have a couple but they want $750 each (don't know the condition)....have seen them advertised in Hemmings as well....
I bought a reproduction LS6 intake from ThePartsPlaceInc on Ebay....they also have a website....
No problems with the repro manifold, carb & gasket surfaces straight & true......it comes with a heat shield (although mine had to be modified for the Gen 6 454HO crate engine) and it fits under the stock BB hood.....
Oh yeah....you'll need a carb spacer
Hope this helps
Thread Starter
Intermediate
Joined: Mar 2002
Posts: 45
Likes: 0
From: Ashville AL
thanks
My brother is using a 435 tri-power on his. I didn't want to spend that kind of money or deal with tuning three carbs. Fuel injection does tempt me, but again too much money right now. The LS-6 looks like what I am looking for. I should have thought a little more about what GM produced under the stock hood. Didn't think about LS-6.
All have been very helpful. Thanks
All have been very helpful. Thanks
Instructor
Joined: Mar 2007
Posts: 223
Likes: 0
From: Henryville Indiana
Why go to all the expense???
My 79 Camaro had a 468 I built with a 722 Lunati roller cam and ported IRON OVAL PORT heads.I made 707hp,642# torque.at 7400 redline.
The aluminum heads are going to cost 1500-2000 bucks +an intake,time,gaskets,etc.
If it was my choice,I'd pull the heads and get them ported and get good springs on them with 1.8 rockers(250.00) and enjoy a 100 hp increase for a lot less money.
Porting usually costs +/- 500.00 valve springs 125.00 and you can tear down the heads yourself,then after porting get a 3 angle valve job with the new parts installed.200.00est.
Just my .02
Craig
My 79 Camaro had a 468 I built with a 722 Lunati roller cam and ported IRON OVAL PORT heads.I made 707hp,642# torque.at 7400 redline.
The aluminum heads are going to cost 1500-2000 bucks +an intake,time,gaskets,etc.
If it was my choice,I'd pull the heads and get them ported and get good springs on them with 1.8 rockers(250.00) and enjoy a 100 hp increase for a lot less money.
Porting usually costs +/- 500.00 valve springs 125.00 and you can tear down the heads yourself,then after porting get a 3 angle valve job with the new parts installed.200.00est.
Just my .02
Craig
Thread Starter
Intermediate
Joined: Mar 2002
Posts: 45
Likes: 0
From: Ashville AL
Why go to all the expense???
My 79 Camaro had a 468 I built with a 722 Lunati roller cam and ported IRON OVAL PORT heads.I made 707hp,642# torque.at 7400 redline.
The aluminum heads are going to cost 1500-2000 bucks +an intake,time,gaskets,etc.
If it was my choice,I'd pull the heads and get them ported and get good springs on them with 1.8 rockers(250.00) and enjoy a 100 hp increase for a lot less money.
Porting usually costs +/- 500.00 valve springs 125.00 and you can tear down the heads yourself,then after porting get a 3 angle valve job with the new parts installed.200.00est.
Just my .02
Craig
My 79 Camaro had a 468 I built with a 722 Lunati roller cam and ported IRON OVAL PORT heads.I made 707hp,642# torque.at 7400 redline.
The aluminum heads are going to cost 1500-2000 bucks +an intake,time,gaskets,etc.
If it was my choice,I'd pull the heads and get them ported and get good springs on them with 1.8 rockers(250.00) and enjoy a 100 hp increase for a lot less money.
Porting usually costs +/- 500.00 valve springs 125.00 and you can tear down the heads yourself,then after porting get a 3 angle valve job with the new parts installed.200.00est.
Just my .02
Craig
I have all of that on a 439ci engine with a little less cam. I bent a valve and have a little money to spend to upgrade the car. 80 pounds lighter with the aluminum heads, 1/2 point higher compression and it will look cool. Also if I break this engine in the future then I can build larger cubes (500+) and still have plenty of flow with the rec heads. New larger carb will be next.
Thanks for the input. My LS6 intake should be here tomorrow.
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Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
Probably the LS6 piece, since you want to avoid the 3x2... which, btw, isn't all that hard to tune as long as it's set up correctly, and it pays off with impressive fuel economy when your cruising around on that 350 cfm primary. Other than being a bit pricey, the biggest drawback is that there's no cold air induction package for it.
I know it's not quite what you're asking, but if you're going to go rect port, Edelbrock's RPM-R's are a good value and won't just kill port velocity as is the case with many other aftermarket big port heads (important at "just" 439 cid). ...and they'll support that 540 it sounds like you're dreaming of (
) just fine, unless you're hardcore. However, do your homework before getting the completed set in case the springs aren't correct for your cam. In that case, you'll need to start with bare ones, a set of Ferrea 6000's, titanium retainers...
I love spending other people's money
I know it's not quite what you're asking, but if you're going to go rect port, Edelbrock's RPM-R's are a good value and won't just kill port velocity as is the case with many other aftermarket big port heads (important at "just" 439 cid). ...and they'll support that 540 it sounds like you're dreaming of (
) just fine, unless you're hardcore. However, do your homework before getting the completed set in case the springs aren't correct for your cam. In that case, you'll need to start with bare ones, a set of Ferrea 6000's, titanium retainers... I love spending other people's money
Last edited by TheSkunkWorks; Jun 14, 2007 at 06:57 PM.
Instructor
Joined: May 2007
Posts: 221
Likes: 11
From: Methuen Ma
I believe the LS 6 intake is a dual plane square bore design, you would need a spacer (adapter) if you used a spread bore carburator design like the quadrajet. If you use a square bore carburator you may need a spacer for linkage clearence or fuel inlet line(s)
Race Director
Joined: Feb 1999
Posts: 16,978
Likes: 7
From: In Dreams There Is Truth Ohio
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 2
From: New Zealand
Linkage interferes with the intake if you don't......the LS6 came with an 800cfm Holley and a carb spacer (and also a heat shield, not shown in my pic)......
.....it shows this clearly in the '71 AIM.....not that we knew that during the install.....a bit of confusion and concern about height until I read the AIM.....the setup fits fine with a drop base air cleaner and a 3 inch filter.....
.....I have no idea why GM didn't make the intake taller....the carb spacer isn't optional.......
.....it shows this clearly in the '71 AIM.....not that we knew that during the install.....a bit of confusion and concern about height until I read the AIM.....the setup fits fine with a drop base air cleaner and a 3 inch filter.....
.....I have no idea why GM didn't make the intake taller....the carb spacer isn't optional.......
Instructor
Joined: Sep 2005
Posts: 180
Likes: 1
71 LS6 vettes came with a 780 holley and no spacer plate. You can add a 1 inch spacer and still clear the hood (barely). The spacer helps give the flat intake some additional volume and I have tried both the open and 4 hole spacer. My 71 ls6 ran its best time with an open spacer, but runs better on the street with a 4 hole.If you do not use a spacer, you can use a 1/4 inch insulated gasket and go to a 3 1/2 air filter with the stock open type air filter. You do need to bend the holley linkage a touch to clear an intake bolt. nothing a pair of pilers cant take care of
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
I have an LS6 intake on my 427 with a Holley 850 (mech. secondaries). I thought the 850 was a square bore and you are saying the LS-6 intake is a spread bore. Does this create a problem?
The engine is an L-88 and when the prior owner put it in the '75, he opted to replace the L-88 intake with the LS-6 to avoid replacing the hood.
Can I make this combination work? Any suggestions here?
The engine is an L-88 and when the prior owner put it in the '75, he opted to replace the L-88 intake with the LS-6 to avoid replacing the hood.
Can I make this combination work? Any suggestions here?
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 2
From: New Zealand
I have an LS6 intake on my 427 with a Holley 850 (mech. secondaries). I thought the 850 was a square bore and you are saying the LS-6 intake is a spread bore. Does this create a problem?
The engine is an L-88 and when the prior owner put it in the '75, he opted to replace the L-88 intake with the LS-6 to avoid replacing the hood.
Can I make this combination work? Any suggestions here?
The engine is an L-88 and when the prior owner put it in the '75, he opted to replace the L-88 intake with the LS-6 to avoid replacing the hood.
Can I make this combination work? Any suggestions here?
Your combination works because the LS6 intake matches the L-88's aluminium rectangular port heads, although you may have lost some HP by not having the high rise intake......
Are you happy with the current combo ?
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
I just bought this 3 weeks ago and haven't really driven it much yet. It is on stands now while I am cleaning up the suspension, steering and brakes (a complete mess). This is almost finished.
I couldn't say if I am pleased because I don't know enough yet. I have thought about finding an original L-88 intake, but would also need a $700 hood to go with it. I am trying to learn what I would gain before making the investment. I figure that I am losing some HP, but I heard the LS-6 intake was pretty good for it's low profile.
Can anyone guess at what is lost by going from the high rise L-88 to LS-6 intake?
I couldn't say if I am pleased because I don't know enough yet. I have thought about finding an original L-88 intake, but would also need a $700 hood to go with it. I am trying to learn what I would gain before making the investment. I figure that I am losing some HP, but I heard the LS-6 intake was pretty good for it's low profile.
Can anyone guess at what is lost by going from the high rise L-88 to LS-6 intake?