Should test fitting longtube headers really be this difficult?

#61
Venom351R said:
well I got the correct size bolts today from the big brown truck. There are 14 bolts in the package (which is full) but I need 16 bolts lol. Oh the joys of a custom set up.... These bolt's are the size for a Chrysler (5/16) not the standard ford 3/8 for header bolts so apparently a Chrysler only needs 14 bolts. I'm going to call ARP later today and see what I can do about getting 2 more additional bolts.

I took a few pics b/c I wanted to be sure if there is an adequate amount of threads left to thread into the head to properly secure the headers.

8a27bf6b.jpg
Click to expand...

It looks ok, but aluminum is soft. Ideally you need 1-1/2 times the thread diameter for length of engagement. I wouldn't trust it at any less than 1 times the diameter in a pinch.

Scott
 

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#63
The header flange is thick that's why I was wondering if there was an adequate amount of thread left. I thought the bolts were going to have more sticking through the flange. So is this like an on the fence thing where they might be ok or might not? They are .750 in length, should I just keep them b/c it is fine or send them back and get 1" bolts.

what does the -18 or -16 mean when it comes to bolt sizes? These are 5/16 -18 bolts. There are ones that are -16 that are an inch long but I got exactly what I was told that the bolt sizes were thats how I ended up with 14 bolts and ones that were .750"

I could swap them out with these.

http://www.summitracing.com/parts/HED-09006/
 
#64
18 is how many threads per inch... (that is a course thread, a 24 would be a fine thread when your talking 5/16" bolts)

You can't go wrong with longer bolts if you have the depth, some aftermarket alum heads for a Ford will not take a 1" long header bolt. (stock bolts are 1" long) so most guys buy 3/4" length....assuming a standard header flange thickness
 
#65
These header flanges are pretty thick, I threaded the .750 bolt all the way into the head. With that being said a 1" bolt should work considering there is the thickness of the header flange that will take up room. I would rather keep these then to send them back and reorder another set for the second time but that's only if its recommended that I should. If the bolts I have now are fine then great but I don't want to keep them if its right on the edge of maybe so so being ok
 
#66
Well, simply because they are 5/16" bolts means they won't work. You need 3/8"-16 bolts for Ford heads. I run 3/4" bolts with similiar thread depth on the backside. Before you commit to a 1" bolt, screw another bolt all the way into the head, and measure how much thread you have coming out the back. Having a bolt that is a little on the short side is better than having one that is too long. Some of those aluminum heads do not have much thread depth in those bolt holes. If the bolt bottoms out in the holes, you will never get them tight, or worse, you will break the head off the bolt trying to get them tight. Those bolts don't have to be that tight on an N/A car. The key is even pressure, and make sure they don't back out. Threads are much more likely to get messed up from cross threading, or removing the header too many times an retorquing. I know I haven't posted in this thread in awhile, but I was stuck at work while the airline was trying to conduct a sleep deprivation experiment on me. I just slept for 10 and a half hours.

Kurt
 
#67
Kurt it won't take a 3/8 bolt they have to be a 5/16. The flange covers up the 3/8 Bolt holes and the holes that Line up with the flange bolts are the 5/16 holes. A 3/8 bolt will not even fit through the holes in the flange. Each of my ports has 4 bolt holes the ones across from each other are 3/8 and the ones digional to each other are 5/16 and those are he ones for the flange pattern. If the 3/8 had fit I would have not have sent the arp studs back to get these ones
 
#68
Kurt....for what ever reason his heads have 5/16" threads in those positions, he found out from Ed after much frusration.

Did you tell them you dont work for SouthWest (I think thats the pilot that fell asleep)
 
#69
Ok, what a pisser. Sorry didn't realize that. I must have not been paying attention. I would surf ebay till you find a good deal on some bolts. You have the advantage of time. You have more then enough bolts to test fit now, and it will be awhile before the headers come back from coating.

http://www.ebay.com/sch/i.html?_fro...=5/16"+header+bolts&_sacat=See-All-Categories

I don't know which specific case you are talking about, but pilots fall asleep all the time. In this last FAA reauthorization bill they re did all the rest rules. Which means they actually made rest rules, because there really weren't any before. They were actually talking about making cockpit naps official. Like specifically stating that it was ok for one pilot to take a quick nap if the other one was awake. We have a saying in the airline business, "Don't let me wake up and catch you sleeping." There is a lot more talk in the news about air traffic controllers falling asleep now. It was a Northwest crew that got caught up in the schedule bidding software on their laptops and overshot their destination by 120 miles.

Kurt
 
#70
Also, keep in mind that ARP uses the same bolts in multiple kits. You might find a smaller kit that has similiar bolts. To give you a perfect example, I lost a head stud nut one time, and couldn't find a nut with the same socket size at Ace, so I went to the performance store and shopped. I found a GM torque converter kit for under $15 that had 3 nuts the same size as the head stud kit.

http://www.summitracing.com/parts/ARP-437-3002/?rtype=10

I'm not positive, but that looks like 5/16" by .750 to me. Just hunt around and find the smallest kit with 5/16" bolts.

Kurt
 
#71
Well I have the 5/16 bolts now I'm just trying to find out if t should get the 1" bolts or keep the .750" depending on if I have an adequate amount of threads to go into the heads as you can see in the pics I posted.

Also I have not sent out the headers yet still waiting until I get the flaming river shaft and try test fitting the passenger side with the trans mount unbolted.
 
#78
Venom351R said:
Well I have the 5/16 bolts now I'm just trying to find out if t should get the 1" bolts or keep the .750" depending on if I have an adequate amount of threads to go into the heads...
Click to expand...

Just stick a small screwdriver into the bolt hole, measure how deep it is. Measure the thickness of your header flange. Add the 2 together and see if a 1" will work. Easy peasy, man.
 
#79
I already threaded the 5/16 bolt all the way into the head, add that length + the flange and a 1" bolt will fit. I know it will fit its just a matter of if I SHOULD and if I NEED to go to a 1" bolt. What I mean by the adequate amount of threads is if there are enough threads to properly secure the headers with the 5/16 bolt as from the picture or if 1" bolt is better suited.
 
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