What was wrong with this cylinder? (pics)

Topic: What was wrong with this cylinder? (pics) (Read 7589 times) previous topic - next topic

What was wrong with this cylinder? (pics)

Reply #30 – April 02, 2013, 10:11:34 PM

So now that I have more information:

0.465" - Holes in gt40p heads (or 15/32)
0.490" - Holes in TW heads
0.435" 7/16" stud outer diameter
0.498" 1/2" stud outer diameter
0.526" 7/16" reducer bushing outer diameter

Between the 7/16 studs and gt40p heads, I can assume a 1/2" stud would typically have a ~0.03" clearance, which brings them to 0.528" (or 17/32). It does indeed look like my aluminum heads are exactly between 1/2" and 7/16" bolt holes. The previous head owner says that they were drilled for use on a 351, and he included the 1/2" studs, but only the threads fit in the head - not the shank. Safe to bolt on and go, or should I try drilling them out myself and use the reducer bushings? I'd do one at a time and re-torque as to not disturb the compressed head gaskets which I was unable to find for cheaper than $36/ea ($43 at the parts stores).

The stud looks like this with the clearances:

What was wrong with this cylinder? (pics)

Reply #31 – April 03, 2013, 10:07:34 AM

I've always used the ARP bushings on heads drilled for 1/2" studs. I found this online about installing the TW heads but it really does not address the head bolt hole diameter issue:

http://static.trickflow.com/global/images/instructions/tfs-dp-4%2C5.pdf

From everything I have read its only the last 1" or so that is 7/16". Alot of guys just flip the head over to the 1/2" side and drill them out to accept the 1/2" studs which will allow you to use the bushings. Mic the opening of the head stud holes on each side of the head and that should confirm it if this is what you have.

Darren

Darren

What was wrong with this cylinder? (pics)

Reply #32 – April 03, 2013, 10:58:32 AM

I question whether this is even necessary though. The clearances aren't too bad, but they are also larger than the holes in the gt40p heads. The bushings won't fit unless drilled out to 17/32".

What was wrong with this cylinder? (pics)

Reply #33 – April 03, 2013, 12:00:41 PM

If he has 7/16" studs then its either hardened washers or the bushings. I would drill them if I already had the bushings just because its cheap and if I ever upped the anti to a 351W motor they would be ready to go or if I wanted to sell them they would be more marketable.

With them already on the car and gaskets in the equation some hardened washers from Fastenal would do the trick and cost less.

Darren

What was wrong with this cylinder? (pics)

Reply #34 – April 03, 2013, 12:17:43 PM

I thought the ARP studs come with hardened washers? I picked up some additional grade 8 washers from the store last night.

I also understand that many people re-clamp down head gaskets multiple times and never have an issue on NA motors. These aren't graphite gaskets so it is possible that could also work, but I've never "reused" a head gasket before and not sure I'd trust it. Otherwise, I'd just pull them and run a 17/32" drill bit down each hole. I'm not sure I can drive them in straight from the top. If the bottom of the holes are 1/2" and not 17/32, there'd be no point in pulling them in the first place - I just need the top to be opened up enough for the bushings.

What was wrong with this cylinder? (pics)

Reply #35 – April 03, 2013, 04:23:03 PM

Trick flow is also telling me to run it as is with the hardened washers that the studs came with. He couldn't provide me with the hole diameter at the top of the bolt holes when the heads are new. If I were to do this, I think I'd want to use a second washer since the grade 8 ones I purchased from the hardware store are a little larger on the outer diameter and fit nearly snug into the upper bolt seats.

What was wrong with this cylinder? (pics)

Reply #36 – April 03, 2013, 05:26:01 PM

If you have a Fastenal near you get what is called a Williams Washer:

http://www.fastenal.com/web/products?searchmode=productSearch&rfqXref=&rfqKeyword=&rfqId=&rfqLineId=&r=~|categoryl1:%22600000%20Fasteners%22|~%20~|categoryl2:%22600089%20Washers%22|~%20~|categoryl3:%22600107%20Williams%20Washers%22|~

I run these on my lower intake with studs. We have used them with the ARP studs on heads when washers come up missing.

Darren

What was wrong with this cylinder? (pics)

Reply #37 – April 03, 2013, 05:49:58 PM

Interesting - they must do retail sales? I've been wondering what company I could go to for retail fastener sales - all the ones I found by searching "fasteners" were wholesale only. We have seven in the area. What's the reason for those washers? I'm not sure the tiny clearance I have would be of any issue? They look nice with the bevel though.

What was wrong with this cylinder? (pics)

Reply #38 – April 03, 2013, 06:21:44 PM

Yup, you can walk right in and buy off the street. If you know any contractors they usually have an account and get better pricing. You can use their account and pay cash. I believe Grainger also carries them but you would have to verify that. These washers are smaller OD and hardened versus what you buy in a hardware store.

Darren

What was wrong with this cylinder? (pics)

Reply #39 – April 04, 2013, 12:59:40 PM

I will need to elongate the bolt holes on the lower intake to get the thing to clamp down to the heads - the .030 milled heads are just slightly too much. The port alignment is close sitting loose on top of old gaskets, but I think it will work out after clamping down the new gaskets. Got the new/painted power steering bracket installed (Thanks Vinnie!), although I was having problems getting the pulley on all the way - I will pull it again and lube it up better. I think I will be firing this off on Saturday. I figure re-check everything tonight, install intake, finish power steering, make studs for the accessory brackets into heads, torque down rocker arms, and install alternator/AC. Tomorrow do compression check, headers, hook up exhaust, reinstall radiator and fan, lower intake, button things up. Saturday fire off and perhaps try to get the tags updated so I can take the car out - they expired on the 31st. After cleaning up, I may try to finish the LED tail lights, but I don't see those being installed for another week, if the motor works out as planned. I would like to get them done so the lower lights are as bright as the high brake lamp.

What was wrong with this cylinder? (pics)

Reply #40 – April 04, 2013, 01:08:55 PM

Below I changed the intake valve to use a 6.650" pushrod length. Being shorter, it is more centered, but the sweep has increased greatly.

The following contact widths were found last night:

6.650 pushrod - 0.045 sweep
6.700 pushrod - 0.039 sweep
6.750 pushrod - 0.041 sweep

The exhaust valve above had a sweep of around a ridiculously low 0.020" (it must be a little larger than the silver contact path, as that number is approaching impossible with 0.47x lift). The exhausts all look much better than the intakes.

What was wrong with this cylinder? (pics)

Reply #41 – April 04, 2013, 02:09:43 PM

As a reference, this is compared to 6.700" pushrods:

What was wrong with this cylinder? (pics)

Reply #42 – April 04, 2013, 04:48:18 PM

Looking at the pictures I would go with the 6.700" pushrod over the 6.650" pushrod. You're running 1.7 roller rockers correct?

What was wrong with this cylinder? (pics)

Reply #43 – April 04, 2013, 05:23:06 PM

I would have the intake milled to match the heads. Were the heads angle milled or just flat milled? I had my old 351W DOZZ heads angle milled and had to get the lower milled to match them up. It was around $100 but when it was bolted down the ports matched perfectly and it never leaked.

Did you just buy a bunch of push rods or did you get your hands on a push rod length checker kit? I finally broke down and bought one and its been used and borrowed a few times.

Darren

What was wrong with this cylinder? (pics)

Reply #44 – April 04, 2013, 06:45:06 PM

1.70 RR's yes - they came with the heads. I picked up 6.700" pushrods since I assumes it'd be around correct for heads milled .030 and a shaved block (since TFS includes 6.750 with their kits on unmolested engines). I have an adjustable pushrod that I was using, and ended up needing to purchase a larger caliper to accurately measure the pushrod lengths.

Flat milled. The machinist thinks the intake is fine to run as is (and they were perfectly straight with his straightedge), and I think I'm of the same opinion. He has found these small differences in the port alignment to be undetectable on a dyno. I was using a wire and feeling around where the two met up and it just barely catches (more of the gasket hole than anything else). Since the head is opened up just a hair more than the intake, I think the catch that I am seeing on the end of the intake runner means it is sitting just about perfectly aligned to the head ports. Being near impossible to check the top of the ports, I can just go off of that, and how far it sits down without any gasket.

I am a bit surprised that my adjustable pushrod hasn't bent since I don't have lightweight checking springs. 130lbs seat pressure (330 open at 0.47 lift) is apparently fine for the lower quality TFS adjustable.

I will do some final checks tonight and make a final decision. I've done the measure 20 times, then bolt on method of rebuilding this topend :p