International M propane flow numbers

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Racing68
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International M propane flow numbers

Post by Racing68 »

Anyone have a flow sheet for an International M propane head.
mag2555
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Re: International M propane flow numbers

Post by mag2555 »

Oh boy!
I’am not even sure I want to ask why there needed, lol!
You can cut a man's tongue from his mouth, but that does not mean he’s a liar, it just shows that you fear the truth he might speak about you!
NebrRex
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Re: International M propane flow numbers

Post by NebrRex »

Probably antique tractor pulling. The red ones need help to run with the green ones. :mrgreen:
That info might be hard to come by. It seems to me the tractor guys are more secretive than the car guys.
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Racing68
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Re: International M propane flow numbers

Post by Racing68 »

It's an antique pull tractor 4.375 bore 7.5 stroke 1600 rpm. I just did the head only. Here's what i got out of it. 1.900 intake valve 1.700 ex valve

Lift Int EX
.100 61.9 57.9
.200 121.4 115.8
.300 171.4 151.6
.400 202.3 176.4
.500 216.6 190.2
.600 219.0 195.7
.700 219.0 201.2
mag2555
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Re: International M propane flow numbers

Post by mag2555 »

The exh side on those heads work very well, maybe too well!

The exh to intake valve ratio and the overall exh to int flow ratio up to .500” lift are the same, that being a big 89% !

If you can’t step up to a bigger intake valve I would for sure not back cut the exh valve, but definitely back the intake valve.

I guess now the question is can the intake manifold support or exceed what the heads can flow.
You can cut a man's tongue from his mouth, but that does not mean he’s a liar, it just shows that you fear the truth he might speak about you!
Racing68
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Re: International M propane flow numbers

Post by Racing68 »

That was the smallest ex valve vs port size i could do, and the intake is as big as it can go without moving valve location. I got the cam info and it is running 224@.050 int and ex .578 int and .518 ex with 1.9 int and 1.7 ex rockers. Customer said it is getting a custom made intake and exhaust, so that could good or bad depending on who did them. I've seen guys use 2 inch square tube to make both int and ex manifolds for ports that are 1 5/8 in round or smaller so hopefully not one of those guys. If you wanna see port work and valve jobs that would make you sick, start doing cylinder heads for antique tractor pullers. Last antique puller head i did was about 3 months ago it had a 2.125 valve 2.00 seat location 95% throat and 0/45/90 valve angles. I fixed it and picked up 27 HP on a tractor that was about 160 HP.
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Re: International M propane flow numbers

Post by mag2555 »

Yup. It’s amazing what can take place when you regain lost flow in the mid lift region, and just as important port velocity, right?
You can cut a man's tongue from his mouth, but that does not mean he’s a liar, it just shows that you fear the truth he might speak about you!
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