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Old 11-09-2022, 11:53 AM
15bhardwick 15bhardwick is offline
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Default Wide Ports on Stock Block

Anyone running a wide port style/2.200+ valve head on a stock block?

Picked up a set of kauffman offset high port heads, supposed to be about 400 cfm but takes a big valve and shaft rockers. Have a 030 455 short block with rock in it as a candidate. Will valves be too close to cylinder walls?

Not really in the budget right now for a new aftermarket block unless someone has a used one they'd part with.

Really want the stock block to work since I have parts for it.

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Old 11-09-2022, 12:06 PM
Steve C. Steve C. is online now
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Minimum bore size of 4.150 so the .030-over would in theory work.


.

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Old 11-09-2022, 12:11 PM
15bhardwick 15bhardwick is offline
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Yeah saw the 4.150 minimum on kauffmans website. The in theory part is what more of my question was about. It will fit but will it "work" correctly

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Old 11-09-2022, 12:58 PM
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Tom Vaught Tom Vaught is offline
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Usually assuming for "one change" vs looking at the whole package of parts and their interaction does not lead to much more than a "roll the dice" situation.

But you have someone to blame.

Tom V.

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Old 11-09-2022, 01:24 PM
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25stevem 25stevem is offline
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KRE has had then on a 463 cid and claim they made 700 hp, so yes they will work for your bore size.
I can only assume that they built that motor with a nice intake valve chamfer in the deck which is something you should have and or put in on your block.

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Old 11-09-2022, 01:40 PM
Steve C. Steve C. is online now
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Does the purchase include valve train pieces ?

If not, some considerations:

With the larger diameter and longer valves, taller valve springs are required, this all adds to valvetrain mass. Keep this in mind with spring selection.

Overall height is taller and longer push rods are required. Upgrade to a thicker wall section.

The obvious, if the shaft rocker system utilizes off-set intake rocker arms you are limited to solid roller lifters.

You can presume that 400 cfm rating is at high valve lift. Related it also brings up the question of the intake port size and intake manifold choice and any potential intake port matching issues.
As cast the port opening is about 2.300" tall.

Consider the taller overall height if hood clearance is an issue.


.

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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

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5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE
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Old 11-09-2022, 03:12 PM
15bhardwick 15bhardwick is offline
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Quote:
Originally Posted by Steve C. View Post
Does the purchase include valve train pieces ?

If not, some considerations:

With the larger diameter and longer valves, taller valve springs are required, this all adds to valvetrain mass. Keep this in mind with spring selection.

Overall height is taller and longer push rods are required. Upgrade to a thicker wall section.

The obvious, if the shaft rocker system utilizes off-set intake rocker arms you are limited to solid roller lifters.

You can presume that 400 cfm rating is at high valve lift. Related it also brings up the question of the intake port size and intake manifold choice and any potential intake port matching issues.
As cast the port opening is about 2.300" tall.

Consider the taller overall height if hood clearance is an issue.


.
Right now all I have is a block, pistons, and old eagle rods that I was possibly planning to replace. So I was already planning to order everything else for the heads along with bearings and other misc. items for the short block. Roller cam and lifters is a must along with the shaft rockers. Have read that the drawback to the highports are the longer/heavier valves. I would plan on ordering an intake for the heads if I had some good recommendations. Northwind and polar wind were coming to mind. Not sure if a Victor or BOP would work. Have a hood scoop so clearance there is not an issue

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Old 11-09-2022, 06:01 PM
Dragncar Dragncar is offline
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Quote:
Originally Posted by 15bhardwick View Post
Right now all I have is a block, pistons, and old eagle rods that I was possibly planning to replace. So I was already planning to order everything else for the heads along with bearings and other misc. items for the short block. Roller cam and lifters is a must along with the shaft rockers. Have read that the drawback to the highports are the longer/heavier valves. I would plan on ordering an intake for the heads if I had some good recommendations. Northwind and polar wind were coming to mind. Not sure if a Victor or BOP would work. Have a hood scoop so clearance there is not an issue
Run a Victor. Northwind is a compromise and you do not have a hood clearance issue.
Polar Wind ? I would not consider it unless the engine is huge. BOP, not sure they are even available anymore.
I have 2.20 valves on a 4.155 bore with High Ports. The longer heavier valves should not be a issue as long as you run a cam that will make power under 7000RPM and since you have a stock block I would keep it to 6500RPM or so.
You are going to need to run the right valve spring for the RPM and cam you are running. Too much spring pressure can cause problems for a stock block.

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Old 11-09-2022, 06:21 PM
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25stevem 25stevem is offline
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Just as good insurance I would do up a lifter bore brace.
If the money is there for it titanium intake valves will ease the needed valve spring pressure and thus the side load on the lifter bores.

I would look into running PAC Beehive springs like the 1255X.

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Old 11-09-2022, 08:12 PM
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Bill Eveland Bill Eveland is offline
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My 469 had 380 High Ports with a 2.25 valve on a 4.210bore. Victor intake.. i believe i have some 10.300 .080 Trend pushrods leftover , i ended up with 10.400

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Old 11-10-2022, 10:25 AM
Steve C. Steve C. is online now
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We run a Victor intake on our engine in the Fairmont with High Port heads mentioned in signature below.


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__________________
'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE
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