Having trouble with intake...

csouth · January 16th, 2009, 10:53 PM

I havent posted in a while, but I need some help. I installed a new Edelbrock Performer RPM. I'm having a problem finding the right size heater hose fitting. The one closest to the brake booster is 3/8. The passenger side is not 1/2 and 5/8 could take a thread. I dont want to cross thread anything. I know I could alwyas run the hose to the drivers side, but I still need to know the size if I were to block it off. Can anyone offer some insight?

J-(Chicago) · January 17th, 2009, 12:43 AM

Cut the head off of your old heater control valve and run your heater core line to that pipe.
If you want to block it off, just pinch the pipe closed and weld it shut.
Saves a trip to the hardware store.

joe_padavano · January 17th, 2009, 10:12 AM

Quote:

Originally Posted by csouth

I havent posted in a while, but I need some help. I installed a new Edelbrock Performer RPM. I'm having a problem finding the right size heater hose fitting. The one closest to the brake booster is 3/8. The passenger side is not 1/2 and 5/8 could take a thread. I dont want to cross thread anything. I know I could alwyas run the hose to the drivers side, but I still need to know the size if I were to block it off. Can anyone offer some insight?

That's supposed to be pipe thread, which are tapered. If the threads weren't tapped deeply enough, that could be the problem.

csouth · January 17th, 2009, 03:30 PM

Joe,
Do you think i should run a 5/8 thread chaser through it? I'm trying not to ruin a brand new intake, ya know...

joe_padavano · January 17th, 2009, 03:35 PM

Quote:

Originally Posted by csouth

Joe,
Do you think i should run a 5/8 thread chaser through it? I'm trying not to ruin a brand new intake, ya know...

I would run a PIPE thread tap through it. I assume that's what you mean. A standard 5/8" straight thread tap is not correct.

citcapp · January 17th, 2009, 05:32 PM

Make sure you are trying a 5/8" pipe thread fitting and not a fine thread fitting, that could be your problem. You can find brass pipe thread fittings at the plumbing or hardware stores at least around here you can no problem. Good luck

csouth · January 18th, 2009, 10:16 PM

I'm going to give Edelbrock a call on Monday. I measured the diameter and it looks like 15/16th's.

joe_padavano · January 19th, 2009, 11:11 AM

Quote:

Originally Posted by csouth

I'm going to give Edelbrock a call on Monday. I measured the diameter and it looks like 15/16th's.

Well, the tap drill size for 3/4-14 NPT thread is 29/32", so that sounds about right.

joe_padavano · January 19th, 2009, 11:14 AM

This link might be helpful:

http://www.plumbingsupply.com/pipethreadsizing.html

csouth · January 19th, 2009, 01:07 PM

Joe
I talked to Edelbrock and was told 3/4 NPT. I picked up a fitting and will try when I get home this evening. Thanks for the link the chart BTW. I'll let you know how it goes...

gearheads78 · January 19th, 2009, 01:57 PM

As Joe says pipe thread is not like std threads. I 3/4 bolt will fall through a hole for 3/4 pipe.

csouth · January 19th, 2009, 02:33 PM

Gothcha. I went to NAPA during my lunch break. The fitting I picked up was 3/4 NPT as stated by Edelbrock. I'm hoping this works.

csouth · January 19th, 2009, 06:29 PM

Seems like it is 3/4 NPT. I tried a bushing and was going to add a 1/2 heater hose fitting, but I don't like the look. I'm just going to order the correct part. Thanks for all your input guys...

January 17th, 2009, 12:43 AM	#2 (permalink)
J-(Chicago) Seasoned beater pilot. Join Date: Jan 2007 Location: Chicago Posts: 2,697	Cut the head off of your old heater control valve and run your heater core line to that pipe. If you want to block it off, just pinch the pipe closed and weld it shut. Saves a trip to the hardware store. __________________ I'd rather have a numbers matching poker hand.

January 17th, 2009, 03:30 PM	#4 (permalink)
csouth Registered User Join Date: Nov 2008 Location: Detroit, MI Posts: 194	Joe, Do you think i should run a 5/8 thread chaser through it? I'm trying not to ruin a brand new intake, ya know... __________________ Chris Takin' Baby steps.... '72 Cutlass S

January 17th, 2009, 05:32 PM	#6 (permalink)
citcapp Super Moderator Join Date: Nov 2007 Location: Bothell, WA Posts: 3,453	Make sure you are trying a 5/8" pipe thread fitting and not a fine thread fitting, that could be your problem. You can find brass pipe thread fittings at the plumbing or hardware stores at least around here you can no problem. Good luck __________________ Pat 1957 Super 88 with a 455 1948 2dr series 76 with a 455

January 18th, 2009, 10:16 PM	#7 (permalink)
csouth Registered User Join Date: Nov 2008 Location: Detroit, MI Posts: 194	I'm going to give Edelbrock a call on Monday. I measured the diameter and it looks like 15/16th's. __________________ Chris Takin' Baby steps.... '72 Cutlass S

January 19th, 2009, 11:14 AM	#9 (permalink)
joe_padavano Super Moderator Join Date: Mar 2007 Location: Northern VA Posts: 4,402	NPT thread dimensions This link might be helpful: http://www.plumbingsupply.com/pipethreadsizing.html __________________ Joe Padavano 64 Jetstar 88 Conv 66 442 L-69 Conv 68 W-30 69 H/O 69 442 70 W-30 72 442 84 Custom Cruiser 86 Caprice wagon (w/307 Olds)

January 19th, 2009, 01:07 PM	#10 (permalink)
csouth Registered User Join Date: Nov 2008 Location: Detroit, MI Posts: 194	Joe I talked to Edelbrock and was told 3/4 NPT. I picked up a fitting and will try when I get home this evening. Thanks for the link the chart BTW. I'll let you know how it goes... __________________ Chris Takin' Baby steps.... '72 Cutlass S

January 19th, 2009, 01:57 PM	#11 (permalink)
gearheads78 Super Moderator Join Date: Apr 2008 Location: Dallas TX Posts: 1,565	As Joe says pipe thread is not like std threads. I 3/4 bolt will fall through a hole for 3/4 pipe. __________________ -Richard 66 Cutlass ragtop my way Keep watching your cotton candy coated TV while your world falls apart around you...

January 19th, 2009, 02:33 PM	#12 (permalink)
csouth Registered User Join Date: Nov 2008 Location: Detroit, MI Posts: 194	Gothcha. I went to NAPA during my lunch break. The fitting I picked up was 3/4 NPT as stated by Edelbrock. I'm hoping this works. __________________ Chris Takin' Baby steps.... '72 Cutlass S

January 19th, 2009, 06:29 PM	#13 (permalink)
csouth Registered User Join Date: Nov 2008 Location: Detroit, MI Posts: 194	Seems like it is 3/4 NPT. I tried a bushing and was going to add a 1/2 heater hose fitting, but I don't like the look. I'm just going to order the correct part. Thanks for all your input guys... __________________ Chris Takin' Baby steps.... '72 Cutlass S

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