What's wrong with AFR's exhaust port?

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05-27-2015 | 08:09 AM

#291

MER Performance

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From: Little River SC

Quote:

Originally Posted by Full Force

I put valve in oven at 400 degrees put in guide was very snug, yes a hillbilly test but makes ya go hmmmmmm

Did you, heat the head also?

05-27-2015 | 08:09 AM

#292

MILD THUNDER

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From: chicago

Quote:

Originally Posted by Full Force

I have been informed within recent to have every head custom built by a trusted machinist local to you that you trust, 7 people told me that in last 2 days gonna leave it there....

Kinda hard to argue with that, when even AFR tells you to do so, to set the guide clearances.

05-27-2015 | 08:13 AM

#293

Black Baja

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From: bel air, md

I'll get some measurements later on this week. I have a brand new set out of the box.

05-27-2015 | 08:18 AM

#294

mike tkach

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From: yorkville,il

Quote:

Originally Posted by Budman II

I am running the same lifters and heads in my boat. Now I am going to be tossing and turning at night wondering if I'm going to drop a valve the next time I take the boat out.

I wonder how many of us are running the AFR heads out there out of the box without having checked guide clearance and exhaust valve seat width.

this is the down side of a thread like this.people who are running afr heads are going to loose sleep wondering if this will happen to them but we don,t yet know for sure what caused the failure.tim,if you have more info on the cause of the failure please post it.

05-27-2015 | 08:21 AM

#295

Full Force

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From: Olmsted Falls,Ohio Marblehead,Oh

Quote:

Originally Posted by mike tkach

Trying to wait for 2 things, to pull other heads and check them... And also to see if anyone makes my situation a better one, you know what's going on, i wish I did things much differently..

05-27-2015 | 08:21 AM

#296

JRider

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From: MI

Quote:

Originally Posted by Full Force

I have been informed within recent to have every head custom built by a trusted machinist local to you that you trust, 7 people told me that in last 2 days gonna leave it there....

On an intake valve? I can see issue arising on the exhaust for sure, but the intake?

05-27-2015 | 08:38 AM

#297

Cole2534

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From: OK CIty, OK

Quote:

Originally Posted by Black Baja

I'll get some measurements later on this week. I have a brand new set out of the box.

I'm curious about your process. Gonna measure roundness, diameter, and straightness? Good gauge pins would make that a snap for a go/no go test. Or do you have some small diameter, deep bore gauges? The machining nerds wanna know!

05-27-2015 | 08:51 AM

#298

Black Baja

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From: bel air, md

Quote:

Originally Posted by Cole2534

Headed out of town this evening to pick up a buddies motor. Just spoke to the guy that built his motor he has a sunnen dial bore gauge. I have a dis-assembled head in my truck so I'll get him to run the bore gauge through the head and I'll report results this evening. I'm pretty sure I have a pin gauge set (have to find it may have lent out and not returned) will try and run the pins through the head later this week. I have a million different things going on right now and my motor is on the back burner so I'll try to get to it as soon as possible...

05-27-2015 | 09:09 AM

#299

MER Performance

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From: Little River SC

I looked over this posting here, kind of fast.
All of the AFR heads I have used, I have always checked valve to stem clearance, they have all been .0015". Actually; if I'm installing new guides, I set the intake @.0001 and the exhaust at .0015" even for forced induction applications, this is for a 11/32 valve stem. If you are running a 3/8" valve, I would run .0015 int and .002' exhaust.
A intake valve is never going to see 400 degrees, with a fuel/ air charge flowing over it, unless you overheating the block.