My home ported 302 heads....what do you see?
- Thread starter bschubarg
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yellow rose
Overnight Sensation
Why is the valve so proud?
ConValiant64
Well-Known Member
Shaved it a bit much, didn't you? I see the valve extending past the deck.
I was reading last night something about 30* seats??
New style valves for the seats?
New style valves for the seats?
bschubarg
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You get a cookie!
yellow rose
Overnight Sensation
All I will say is a 30* seat is a colossal waste of time and effort. It's a power loser every time.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Hey, I seen those in lawnmowers! Old Flatties,lol
Still
an interesting idea, but
How will a 30*exhaust valve not cause pre-ignition leading to detonation?
Still
an interesting idea, but
How will a 30*exhaust valve not cause pre-ignition leading to detonation?
No dog in the fight, I'm a newbie to a lot of the engine building. I came across this article when I googled 340 porting.
Here's the link.
360 Engine Head Porting - Mopar Muscle Magazine
Here's the link.
360 Engine Head Porting - Mopar Muscle Magazine
RAMM
Well-Known Member
My home ported 302 heads....what do you see?
My first thought was --A big waste of time.
I have gone down this road when I bought into the idea of 30* seats and let me tell you it is not new, nor is it particularly effective. By all means though I understand the compulsion to experiment and go your own way-So have at it. Also I was advised by a more experienced head porter with a flowbench that it was ill advised to do this sort of thing without the aid of flowbench. He was right! J.Rob
My first thought was --A big waste of time.
I have gone down this road when I bought into the idea of 30* seats and let me tell you it is not new, nor is it particularly effective. By all means though I understand the compulsion to experiment and go your own way-So have at it. Also I was advised by a more experienced head porter with a flowbench that it was ill advised to do this sort of thing without the aid of flowbench. He was right! J.Rob
MOPAROFFICIAL
Oogliboogli
You relieved the chamber below the seat, unshrouding the valve.
If you pick up too much velocity, it'll take the rest of the bowl with it..beeeeee carefulllllllll
If you pick up too much velocity, it'll take the rest of the bowl with it..beeeeee carefulllllllll
1.88 valves in 1.78 holes?
bschubarg
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All good advice.... I’m not looking to win races or make this project into a dyno queen... I’m experimenting so I can learn and have first hand experience... best part is I will share my success or failure here... I often take the path least followed... which is why I’m a Mopar fan... and Oldsmobile fan...
famous bob
mopar misfit
What I see, I don`t like for sure .
international truck gas engines all used a 30 deg intake seats but had a very large head chamber to work with the seat there was no way the valve could be shrouded a 304 2 barrel engine used a 2.02 intake valve
Let me get this right. You stuck the valve head up into the combustion chamber to increase the compression ratio? That was your big idea? I guess you could weld flat washers and nuts onto the valve heads also. That'd jack the compression up too.
yellow rose
Overnight Sensation
MOPAROFFICIAL
Oogliboogli
Welding takes too much time...just leave'em sit on the pistons before bolting the heads on.
Flow window.....and stable air flow....
Low rpm engine making torque and reliability, is a whole other thing.
bschubarg
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Again... I'm just experimenting; doing what everybody is doing or what everybody tells you should do...isn't innovative.
I'm almost ready to get this beast running and so far no issues with clearances.
There are certainly two opinions on using #302 heads. I subscribe to neither.
My goal is taking this heavy Chrysler 5th Ave(#3780 lbs) with advertised HP rating of 140 and a 1/4 Mile time in the high 17 second to a #3450 lb(Currently) HP rating of ~275 and a 1/4 Mile in Mid to Low 14's.
Wish me luck....
I'm almost ready to get this beast running and so far no issues with clearances.
There are certainly two opinions on using #302 heads. I subscribe to neither.
My goal is taking this heavy Chrysler 5th Ave(#3780 lbs) with advertised HP rating of 140 and a 1/4 Mile time in the high 17 second to a #3450 lb(Currently) HP rating of ~275 and a 1/4 Mile in Mid to Low 14's.
Wish me luck....
MOPAROFFICIAL
Oogliboogli
Using different valves, bigger will generally always raise compression a lil. The main thing here is they won't make a torque monster 'relatively speaking' unless they flow what a 360 head flows.
You want velocity with flow, not just velocity.
A factory 340 made what, 340 ft lbs of torque?
Make 318/273 heads follow with what some 587/915 castings flow and it can make 40 lbs more tq.
bschubarg
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Totally agree... My previous post illustrate what I did to the #302 heads... i.e. porting. Hopefully I gained more flow with velocity. We are on the same page MOPAROFFICIAL.....
yellow rose
Overnight Sensation
I'm all for innovation. If you want to innovate, you need tools to test with. That would be a flow bench and a dyno and then the track. If all the numbers don't add up, you need to learn why they don't.
Just rehashing a junk valve job without testing properly isn't innovation. It's mental masturbation.
I've tested many valve jobs. The LAST valve job I'd use is a 30 degree seat. Can't tell you how many Pontiacs I converted to 45* seats. The poncho purists all lose their collective minds. I tell them if they had a mind they wouldn't be screwing with Pontiacs, and I say that after I just did 3 hard days in a Pontiac sweat shop.
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