Porting small block 915 j-heads
- Thread starter kma
- Start date
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So.. Done some testing to get a feel for it.
Started to mill down the guides a 1/4"
Still waiting for new valves and guides so this is not the finished "boss"??
Started to mill down the guides a 1/4"
Still waiting for new valves and guides so this is not the finished "boss"??
PRH
Well-Known Member
Looks like you’re going after it pretty good!!
PRH
Well-Known Member
I’ve hit water in the area where that red arrow is.
A little more towards the bowl and the floor.
A little more towards the bowl and the floor.
yellow rose
Overnight Sensation
Got hold of a 587 casting and cut it up. Made a template for the short side turn to be sure not going too far.
The rod ends under my thumb along with the macined surface to get the same distance on all turns.
Don´t know if the angle is wrong. It´s up to you pros to decide.
Some material is gonna go when the throat is cut for 1,94" valve so there will be a more steaper angle towards the end
The cut is about ,100" deep
The rod ends under my thumb along with the macined surface to get the same distance on all turns.
Don´t know if the angle is wrong. It´s up to you pros to decide.
Some material is gonna go when the throat is cut for 1,94" valve so there will be a more steaper angle towards the end
The cut is about ,100" deep
MOPAROFFICIAL
Oogliboogli
PRH
Well-Known Member
What you should do on the junk head is, cut as much out of that corner where the red arrow is as you think you want to.
Then cut the head right along that area in the corner to see what’s left.
It’s rare that you see a hole in the center of the SSR.
It’s usually in one of the corners.
Then cut the head right along that area in the corner to see what’s left.
It’s rare that you see a hole in the center of the SSR.
It’s usually in one of the corners.
Ok. That picture you painted in isn’t worked at all anywhere but on the side of the guide. Testing the lower head bolt.
On this picture my “template cut” is blended out. Haven’t done the bowl cut for 1,94” yet so your painting is good to have. Thanks
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PRH
Well-Known Member
I’m not sure how much flow you’re going after, but you can leave that hump in the corner mostly untouched and still end up in the mid-250’s.
PRH
Well-Known Member
@PRH
@MOPAROFFICIAL
@'63GT
If you use 11/32 valve guides where do you buy it ? Part nr. ? I assume I need manganese bronze
Have found at Competitionproducts for Chevy SB. Do they fit ? ,502 OD but have no length yet.
My machine shop ordered from Summit but they were back ordered and have been for four weeks. They couldn´t wait for them though they had other things ordered that they wanted asap
@MOPAROFFICIAL
@'63GT
If you use 11/32 valve guides where do you buy it ? Part nr. ? I assume I need manganese bronze
Have found at Competitionproducts for Chevy SB. Do they fit ? ,502 OD but have no length yet.
My machine shop ordered from Summit but they were back ordered and have been for four weeks. They couldn´t wait for them though they had other things ordered that they wanted asap
Check Ebay. There are some sellers in your area who are selling what you need. They're expensive $8-$10 each US. X 16 of coarse. A driver (air hammer) for those guides are about $18 US.
My 11/32 guide liner kit's reamer takes the .342" guide size out to .3715"~.372". I often wondered if a 11/32 liner in a .372 guide would do the trick.
MOPAROFFICIAL
Oogliboogli
For the material a lot of it depends on what you are doing and level of parts.
Iron guide wears the stem faster than the other way around. Bronze wears faster than the valve, though if you use a really nice valve with stems like glass they do better. Drag? Street? Land speed record?
Use the one you feel is gonna live up to your expectation. What valves are you using again?
Iron guide wears the stem faster than the other way around. Bronze wears faster than the valve, though if you use a really nice valve with stems like glass they do better. Drag? Street? Land speed record?
Use the one you feel is gonna live up to your expectation. What valves are you using again?
PRH
Well-Known Member
Manganese .502 x 11/32 isn’t really a “Chevy” guide....... it’s a universal guide.
Just figure out what you need for length and get something close in length, but slightly longer.
They are trimmed for the correct length after installation.
Just figure out what you need for length and get something close in length, but slightly longer.
They are trimmed for the correct length after installation.
yellow rose
Overnight Sensation
MOPAROFFICIAL
Oogliboogli
It´s gonna be a streeter. No records
The intake valves are REV CL 1641 21-4n stainless 1,94" + ,100"
Exhaust is Power products performance stainless , chrome stem 1,625" + ,100" , thats what I know of them
Ordered a complete head improvement kit from Competitionproducts. kit #851296 but I replaced all valves due to length , springs , retainers , locks , seals.
The intake valves got a little more expensive though.
Here are some data on the springs.
Valve Spring Type: Hi-Tech Racing Products Hydraulic/Mechanical Flat Tappet
Valve Spring Size: 1.265" O.D.
Valve Spring Pressure: Closed: 110 @ 1.800", Open: 340 @ 1.150", 1.160" Coil Bind
Valve Spring Max Lift: .570"
Ok. I have asked for the length but haven´t got an answer yet.
It is a decent machine shop but I don´t know if they were out of stock. They had cast iron but it was my fault saying I wanted manganese bronze. I don´t know better
Thanks
Here´s my car if you want to look Swedish 1969 Dart GT
PRH
Well-Known Member
What’s wrong with those numbers?
I don´t know. Tell me
cookietruck
Well-Known Member
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