J Head Porting How does it look?

-
Get that kink out.
You have a 2.08 I take valve? Be easy on reworking that spot then, gotta be thin or getting real thin after that valve went in.
Next set I do I will insist on using 1.625 or so exhaust valves

Flow that port. I wonder by the short turn if it doesn't fall off early
 
Last edited:
MOPAROFFICIAL said:
Gein that kink out.
You have a 2.08 I take valve? Be easy on reworking that spot then, gotta be thin or getting real thin after that valve went in.
Next set I do I will insist on using 1.625 or so exhaust valves

Flow that port. I wonder by the short turn if it doesn't fall off early
Click to expand...
Oh boy I’m in for a time.
 
ValiantKindOfGuy said:
Oh boy I’m in for a time.
Click to expand...
Nah, it could run better than if you didn't report it he just have a little bit of reversion going on and you really don't know what it flows and at how high lift it will carry so in a way you really don't know what cam you should use. Kind of why when guys say they have a stock 360 or stock 318 most of us have about five or six cams we can recommend that are right off the shelf... because we know what those heads do and those cams are designed around them
 
MOPAROFFICIAL said:
Nah, it could run better than if you didn't report it he just have a little bit of reversion going on and you really don't know what it flows and at how high lift it will carry so in a way you really don't know what cam you should use. Kind of why when guys say they have a stock 360 or stock 318 most of us have about five or six cams we can recommend that are right off the shelf... because we know what those heads do and those cams are designed around them
Click to expand...
I already picked this cam based on the fact it was sitting in my shelf lol. It may not work good but it will be fine for when I get a set of LAX heads. I’ll get these flowed and post the results if they need work I will see what I can do but I’m not too knowledgeable when it comes to port design. I’m not sure when I can but hopefully in the next week. If anybody knows someone with a flow bench in mass let me know. The local shops hours makes it a pain with my work hours.
 
Look very close at that valve job. Almost zero top cut and that is certainly a radius under the 45. That is a recipe for a great flowing port that doesn’t make power.

Are your valves back cut? That makes it worse.

I’d bet all you have that port flows 85% or more in reverse as it does forward. That’s bad.

Under the 45 there should be SHARP angles. Nothing close to a radius.

Fix that and it will make power.
 
ValiantKindOfGuy said:
I already picked this cam based on the fact it was sitting in my shelf lol. It may not work good but it will be fine for when I get a set of LAX heads. I’ll get these flowed and post the results if they need work I will see what I can do but I’m not too knowledgeable when it comes to port design. I’m not sure when I can but hopefully in the next week. If anybody knows someone with a flow bench in mass let me know. The local shops hours makes it a pain with my work hours.
Click to expand...


All port work should be done by getting the correct valve job first.
 
A couple valve pictures.

75F1453A-CF00-4552-89EC-92EC761D8785.jpeg


3B8451DE-C33A-45C4-86F6-6A95AB3E4C58.jpeg
 
ValiantKindOfGuy said:
What angles do you suggest?
Click to expand...


I forgot to mention...thin margins are better at killing reverse flow than thick margins BUT...you can get to thin and just use up a good set of valves chasing numbers.

.040-.060 wide margin on the intake and .060-.080 on the exhaust is the best bang for the buck.

If it’s a dedicated race deal, you can go down to .030 on the intake and .045 on the exhaust, but the valves are usually 1 season wonders AND the flow bench will show lower flow numbers with the thin margins I forward flow. But the reverse flow numbers go down way more.

As for a valve job, anything with a 45 degree seat and no more than a 35 degree top cut (a 38 is better...good luck finding one...I had some made for me) and two bottom cuts a 60 and 75.

I don’t care for the 15 degree angles, but that’s about as good as it gets to get the bowl to the correct size. Or, you can use more angles, but once they get less than .060 wide they act like a radius and that’s bad.


I agree with skrews. If you can get Porter to do your stuff, you won’t be sorry.
 
yellow rose said:
I forgot to mention...thin margins are better at killing reverse flow than thick margins BUT...you can get to thin and just use up a good set of valves chasing numbers.

.040-.060 wide margin on the intake and .060-.080 on the exhaust is the best bang for the buck.

If it’s a dedicated race deal, you can go down to .030 on the intake and .045 on the exhaust, but the valves are usually 1 season wonders AND the flow bench will show lower flow numbers with the thin margins I forward flow. But the reverse flow numbers go down way more.

As for a valve job, anything with a 45 degree seat and no more than a 35 degree top cut (a 38 is better...good luck finding one...I had some made for me) and two bottom cuts a 60 and 75.

I don’t care for the 15 degree angles, but that’s about as good as it gets to get the bowl to the correct size. Or, you can use more angles, but once they get less than .060 wide they act like a radius and that’s bad.


I agree with skrews. If you can get Porter to do your stuff, you won’t be sorry.
Click to expand...
Starting to sound expensive haha. I’ll ask my guy tomorrow
 
a2f40ed1-252e-4cc9-b510-170ff22685c5-jpeg.jpg


Interesting how the deposits show up around the exhaust side of the chamber which is usually the hottest area of the chamber.
 

Hysteric said:
Still to me is doesn't look like much is happening on the intake side of the chamber. Low comp and a big carb?
Click to expand...
It had 10:1 and a 600 eddy..... so no
This was not my engine this came from a parts car and had a solid shortblock so I decided to use it.
 
Yep. Intake valve seat is probably not concentric, low by the exhaust seat. 3 angle cutter deflects as it turns and when the top cut load decreases going by the exhaust seat it sinks down a bit creating a low spot.

Assuming the seats were done on a seat guide machine.
 
skrews said:
Yep. Intake valve seat is probably not concentric, low by the exhaust seat. 3 angle cutter deflects as it turns and when the top cut load decreases going by the exhaust seat it sinks down a bit creating a low spot.

Assuming the seats were done on a seat guide machine.
Click to expand...
I think I’m just gonna buy a set of speedmaster heads bare and build them. These will either get sold cheap or thrown in my basement for the future.
 
You must log in or register to reply here.
-

Similar threads

E
TF Porting
2
Replies
35
Views
2K
Earlie A
E
ZMAN24250
New EQ Head port misalignment?
2 3 4 5 6
Replies
140
Views
13K
Confuzed74
C
pittsburghracer
3 more words to drive the head porters nuts.
Replies
9
Views
1K
VOETOM
VOETOM
E
Speedmaster head hypothetical
2 3
Replies
55
Views
4K
Earlie A
E
T
  • Locked
[FOR SALE] Mopar Performance R/T Magnum Heads 2.02
Replies
0
Views
2K
thomasfouraker
T
Back
Top Bottom