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"Big" cams - vacuum pump or vacuum canister?

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Old May 2, 2005 | 06:14 PM
  #16  
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Thumbs up Re: "Big" cams - vacuum pump or vacuum canister?

Hey Jim,

Yeah I'm seeing more and more sbc/rx7 swaps all the time. There was a black one (maybe 93') on LS1.com for sale. Guy's in Florida and this car has an LS1 in it turning low 11's or so. Was asking 27k which I didn't think was too bad when you conider the sweat spent in putting one of these together yourself.

What are you rx7 swappers using for rearends in these builds?

-Mindgame
Old May 2, 2005 | 10:52 PM
  #17  
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Re: "Big" cams - vacuum pump or vacuum canister?

Uh oh..... Mindgame has a idea for a new toy...

Why not go with a I6 of some sort here? Make something along the lines of the TVR 350R..... yummy.

I don't know if a 4200 Vortec with a turbo on it would fit, maybe if you angle it on it's side some, al la E46 M3

Bret
Old May 3, 2005 | 01:21 PM
  #18  
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Re: "Big" cams - vacuum pump or vacuum canister?

Just wondering where I could get a vaccum canister online.. since Im gonna be needing one.. Or just local speedshop could hook me up? Thx
Old May 3, 2005 | 01:56 PM
  #19  
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Re: "Big" cams - vacuum pump or vacuum canister?

any of the online parts depots will have them.I got mine from GMPP as i have alot of GMPP stuff so it matches, and i have friend so i dont have to pay their big $.
I personally prefer to use a local friends or supporting vendors on the board if i can so i dont pay for Jeggies pro stock adventures.
Old May 3, 2005 | 11:53 PM
  #20  
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Re: "Big" cams - vacuum pump or vacuum canister?

Originally Posted by Mindgame
What are you rx7 swappers using for rearends in these builds?
There are 3 options, more or less...

1. Use a Hinson Supercars torque arm and stock differential housing (with an upgraded KAAZ differential and 300M axles) until it grenades. The limitation is 3.90:1 is the lowest gear set you'll find, and the other options are 4.10:1, 4.33:1, and 4.70:1. That's it.

2. Back-half the car and put whatever you want in the back.

3. My '03-'04 Cobra 8.8" IRS setup with hybrid 300M chromemoly axles which retains all the stock suspension, brakes, wheels and tires, and maintains the stock handling of the car (the setup is about 5-6 lbs. heavier overall). No torque arm required, all the gears you can eat.

http://home.gci.net/~jimlab/images/Cobra/PC080013.jpg
http://home.gci.net/~jimlab/images/Cobra/PC080019.jpg
Old May 4, 2005 | 12:38 AM
  #21  
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Re: "Big" cams - vacuum pump or vacuum canister?

BTW, anyone know if you can replace the "steam" hardline that connects the rear of the cylinder heads with NPT/AN fittings and hose? I asked in LT1 land, and of course no one had a clue.

I haven't been able to determine what the thread size of the 2 banjo bolts that go through the "blocks" in the hardline into the heads is yet.
Old May 4, 2005 | 01:08 AM
  #22  
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Re: "Big" cams - vacuum pump or vacuum canister?

Yeah wish I had a pic of what I do.....

I just get the hard line and cut the part that joins the heads and put a AN line in there..... 4AN If I remember right. Keeps everything else and works awesome.

Bret
Old May 4, 2005 | 01:17 AM
  #23  
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Re: "Big" cams - vacuum pump or vacuum canister?

Originally Posted by SStrokerAce
I just get the hard line and cut the part that joins the heads and put a AN line in there..... 4AN If I remember right. Keeps everything else and works awesome.
I thought about that, but the banjo bolts were pretty corroded and I figured I'd start "fresh".
Old May 4, 2005 | 07:44 AM
  #24  
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Re: "Big" cams - vacuum pump or vacuum canister?

I keep the Banjo's because that line is more of a vent line for air bubbles than a line for coolant to run thru. Maintains the flow thru the back of the heads that the factory wanted.

Bret
Old May 4, 2005 | 12:39 PM
  #25  
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Smile Re: "Big" cams - vacuum pump or vacuum canister?

I cut the hardline in half and connect them with a rubber tube and a couple of hose clamps. I think that may not be advanced tech enough for some guys .

Ryan
Old Jul 14, 2005 | 12:19 PM
  #26  
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Re: "Big" cams - vacuum pump or vacuum canister?

Hmm....I have a 245/250ish cam with .620 lift on a 112 LSA. It's in a 12.0:1 383. Based on what I'm reading here, I shouldn't have a vacuum problem, but my brakes think otherwise. I'm getting no vacuum assist whatsoever when I step on the pedal.

What could be the problem? I'm thinking and hoping it may be something stupid like the hose going into the brake booster not sealing up tightly enough. Is that a possibility, or am I just on crack?
Old Jul 14, 2005 | 12:30 PM
  #27  
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Re: "Big" cams - vacuum pump or vacuum canister?

Originally Posted by Mullet Z28
Hmm....I have a 245/250ish cam with .620 lift on a 112 LSA. It's in a 12.0:1 383. Based on what I'm reading here, I shouldn't have a vacuum problem, but my brakes think otherwise. I'm getting no vacuum assist whatsoever when I step on the pedal.

What could be the problem? I'm thinking and hoping it may be something stupid like the hose going into the brake booster not sealing up tightly enough. Is that a possibility, or am I just on crack?
How much vacuum is it pulling? If you don't have a gauge, you need one.

Rich
Old Jul 14, 2005 | 12:33 PM
  #28  
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Re: "Big" cams - vacuum pump or vacuum canister?

Originally Posted by rskrause
How much vacuum is it pulling? If you don't have a gauge, you need one.

Rich
I don't have a gauge, but can I convert the KPAs I'm seeing in LT1 Edit to pounds?
Old Jul 14, 2005 | 03:49 PM
  #29  
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Re: "Big" cams - vacuum pump or vacuum canister?

Originally Posted by jimlab
BTW, anyone know if you can replace the "steam" hardline that connects the rear of the cylinder heads with NPT/AN fittings and hose? I asked in LT1 land, and of course no one had a clue.

I haven't been able to determine what the thread size of the 2 banjo bolts that go through the "blocks" in the hardline into the heads is yet.

I used a braided stainless line in back to replace the hard line. The threads are .25" straight pipe.
Old Jul 15, 2005 | 08:53 AM
  #30  
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Re: "Big" cams - vacuum pump or vacuum canister?

Originally Posted by nateh
I used a braided stainless line in back to replace the hard line. The threads are .25" straight pipe.
Same here. 90 deg. angle fitting (XRP) from pipe to -6 with a T junction in the middle (well offset to the pass. side valve cover actually). I didn't do it for cooling or anything of the sort. I did it to make it easier to pull the heads with the motor still in the car. I hate trying to reach those stupid banjo bolts!



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