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Saw this on eBay, one of the correct early LAT edelbrock f4b manifolds:
http://m.ebay.com/itm?itemId=131684993601&fromWatch=true
http://m.ebay.com/itm?itemId=131684993601&fromWatch=true
Tiger LAT manifold
- Thread starter michael-king
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Steven, what do you mean "clone" ? They made the f4b for quite a while, and improved on the flow when they modified the mounting face to be 2 intake barrels and later with a balancing slot between.
I would hope if you are not going for originality ( which we know from your posts you are not) you would go for a later better flowing manifold. What type of 4bbl manifold have you bought? BTW have you established what manufacturer your heads are?
If you check the other posts on early 289 blocks the heads are explained. The manifold has all the planes needed as well as threaded holes for heater hoses, PCV valve and power brakes. Same as other manifolds. A friend bought a similar manifold without any of the threaded outlet holes. So forget origionality, talk about a reliable Tiger in the 21st Century.
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Think you missed the point of the post and my questions Steven....
Anyway best of luck with it all... Happy new year.
Anyway best of luck with it all... Happy new year.
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Well its 40+ years later.. Next time you do gaskets add the small balance slot too
. ... It's not like its a mod people see
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No photos on hand.. It was basically a small slot cut inline with the central dividing rib that I gather equalised the pressure if the vaccum in the manifold... I'll see if I can find a picture.
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Here are some pictures of the later model 4bbl manifolds that have various versions of the slot I was referring to.
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I saw a writeup on the "slot" somewhere. A prior owner had done it to my f4b.
It's said to increase power a little bit.
66TigerMK1A
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from an old 'list' email...
..."The original version of the Edelbrock F4B manifold had four holes and not two slots. The two slots were added after it was found to add 7-15 HP over the four hole model. Gordon Chittenden's book "Performance Tuning the Sunbeam Tiger" has a photo of the four hole version and has another photo with two slots (pg 111 & 112) and the caption said a machine shop did the work.
Edelbrock incorporated this change in later versions of the F4B."...
I looked in the Chittenden book and there was no balance 'slot'... just the 2 big slots from hogging out the 4 holes ... guess the 'balance' slot was a 'later' development of Edelbrock's on their newer manifolds
A carpenter ( like me ) could make that 'balance' slot pretty quick with a router...
My RPM 'Air Gap' has a 'factory' slot about 1/4" deep
66TigerMK1A
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This is from a discussion on Tigersunited.com ...
To ensure adequate hood clearance, Edelbrock provides manifold heights for all their products, but sometimes leave them out of the catalog by mistake. These dimensions are made with the manifold sitting on a flat level surface. A straight edge is laid across the carburetor pad mounting flange, and the vertical height from the flat surface to the long straight edge are made at the front center of the manifold. This height measurement is called "A".
A similar measurement is made at the rear center of the manifold. This measurement is "B".
The carburetor pad height "CH" is simply A + B divided by 2.
Please note that these statements are valid under two conditions. First, the length of the manifolds being compared is the same. Since they all fit the same sealing surface on the same engine, this is true. The second criteria is that the carburetor mounting flange is located in the same position on all compared models. This statement has been a subject of differing opinions on this list.
According to Edelbrock, The carburetor pad on the Performer 289/302 low rise, the Performer RPM, the F4B, and all other's for this block are not only the same, but are centered in the middle of the block, and directly over the exhaust cross-over in the manifold. This provides even heat under the carburetor, and is in a fixed location on the engine. While certain carburetors may be too long to clear the firewall, at the same "CH", that effect will exist on all manifolds near the same height. The exception, of course, is the F-28 Dual Quad, with TWO four barrel carbs, but they are symmetrically spaced.
Hear are the Edelbrock dimensions:
F4B (2500-7000 rpm design)
A = 4.563 inches
B = 5.313 inches
CH = 4.938 inches
Performer 289/302 (idle-5500 rpm design)
A = 3.50 inches
B = 4.75 inches
CH = 4.125 inches
(This is a 'low rise' manifold, similar to the stock Ford dimensions.)
Performer RPM (1500-6500 rpm design)
A = 4.30 inches
B = 5.50 inches
CH = 4.90 inches
As can be seen, the RPM is 0.038 inches lower than the F4B, giving more hood clearance, although the F4B will fit if you don't use a carburetor higher than the Holley or Edelbrock. Carburetor choice, gasket thickness, thermal barrier spacers and needs for PCV tube plates alter the total height, but would add the same amount to any.
The F4B is listed as a higher rpm manifold than the 'RPM'. Although, the RPM is a more modern design, flows better, and is of a higher quality casting and material. If you are REALLY going to operate in the higher regions, perhaps a Victor Jr., with an RPM range of 3500-8000 rpm, and a CH of 5 50 inches, or Victor 5.0 with a really big 8.25 inches is worth considering for racing.
Warren... if you mean '4-hole' vs. 'dual slot' on the F4B... I doubt anything was changed re height... just the opening was changed
I think my 'Air Gap' manifold is the same height as the Performer RPM ... best solution for the 'mod' crowd IMHO
To ensure adequate hood clearance, Edelbrock provides manifold heights for all their products, but sometimes leave them out of the catalog by mistake. These dimensions are made with the manifold sitting on a flat level surface. A straight edge is laid across the carburetor pad mounting flange, and the vertical height from the flat surface to the long straight edge are made at the front center of the manifold. This height measurement is called "A".
A similar measurement is made at the rear center of the manifold. This measurement is "B".
The carburetor pad height "CH" is simply A + B divided by 2.
Please note that these statements are valid under two conditions. First, the length of the manifolds being compared is the same. Since they all fit the same sealing surface on the same engine, this is true. The second criteria is that the carburetor mounting flange is located in the same position on all compared models. This statement has been a subject of differing opinions on this list.
According to Edelbrock, The carburetor pad on the Performer 289/302 low rise, the Performer RPM, the F4B, and all other's for this block are not only the same, but are centered in the middle of the block, and directly over the exhaust cross-over in the manifold. This provides even heat under the carburetor, and is in a fixed location on the engine. While certain carburetors may be too long to clear the firewall, at the same "CH", that effect will exist on all manifolds near the same height. The exception, of course, is the F-28 Dual Quad, with TWO four barrel carbs, but they are symmetrically spaced.
Hear are the Edelbrock dimensions:
F4B (2500-7000 rpm design)
A = 4.563 inches
B = 5.313 inches
CH = 4.938 inches
Performer 289/302 (idle-5500 rpm design)
A = 3.50 inches
B = 4.75 inches
CH = 4.125 inches
(This is a 'low rise' manifold, similar to the stock Ford dimensions.)
Performer RPM (1500-6500 rpm design)
A = 4.30 inches
B = 5.50 inches
CH = 4.90 inches
As can be seen, the RPM is 0.038 inches lower than the F4B, giving more hood clearance, although the F4B will fit if you don't use a carburetor higher than the Holley or Edelbrock. Carburetor choice, gasket thickness, thermal barrier spacers and needs for PCV tube plates alter the total height, but would add the same amount to any.
The F4B is listed as a higher rpm manifold than the 'RPM'. Although, the RPM is a more modern design, flows better, and is of a higher quality casting and material. If you are REALLY going to operate in the higher regions, perhaps a Victor Jr., with an RPM range of 3500-8000 rpm, and a CH of 5 50 inches, or Victor 5.0 with a really big 8.25 inches is worth considering for racing.
Warren... if you mean '4-hole' vs. 'dual slot' on the F4B... I doubt anything was changed re height... just the opening was changed
I think my 'Air Gap' manifold is the same height as the Performer RPM ... best solution for the 'mod' crowd IMHO