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Old 10-11-2017, 12:22 PM
size-o size-o is offline
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Default Hydroboost vs Vacuum Boost Braking

So what's the consensus on braking methods? My understanding is as long as you have a good power steering pump then your hydroboost will work great. What i don't know is how much vacuum an LS engine will produce to know if thats the better option.

Thanks Again!!
Perry
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Old 10-11-2017, 10:37 PM
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vinces427bb vinces427bb is offline
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how much vacuum is your engine pulling?
higher than 13??
most of the caution on low vacuum is around 8-12.
but, i hear guys can run with 10.5-12.5 most times; but i don't know how often they stop.

hydro-boost systems work great on many vehicles also..
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Old 10-11-2017, 11:12 PM
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Unfortunately I haven't bought the engine yet. I was hoping to attract those with LS engines that might chime in. More research needed

Perry
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Old 10-12-2017, 07:04 AM
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I had a camaro with a major cam. The vacuum assist will work 3X at idle with almost no vacuum. So In traffic I had to pop it in neutral and rev it to get brakes back if it was bad. No harm no foul there the silly car was just about to quit idling at all and stall by that point it needed cleaned out.

Hydroboost is great tho. My van has it and my brother uses it on his 68 charger with the 440 because of the cam.
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Old 10-12-2017, 10:22 AM
mestorod70 mestorod70 is offline
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Having an LS engine or any other brand under the hood makes no difference as
far as brake performance.
What does make a difference is displacement and cam duration.
Cam duration effects vacuum and the bigger the engine the more duration can be
used.
Put a 230 degree at 050 lift cam in a 327.....nasty idle and low vac.
Same cam in a 400 and its very tame nice idle ...lots of vac.
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Old 10-12-2017, 04:39 PM
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The LS I'm looking at is a GM crate motor LS376/525. Below are the spec's. Hmm, I may have an issue so perhaps hydroboost might be the way to go.

Part Number: 19301360
Engine Type: LS-Series Gen-IV Small-Block V-8
Displacement (cu. in.): 376 (6.2L)
Bore x Stroke (in.): 4.065 x 3.622 (103.25 x 92 mm)
Block (P/N 12623967): Cast aluminum with six-bolt, cross-bolted main caps
Crankshaft (P/N 12597569): Nodular iron
Connecting Rods (P/N 12607475): Powdered metal
Pistons (P/N 19207287): Hypereutectic aluminum
Camshaft Type (P/N 88958770): Hydraulic roller
Valve Lift (in.): 0.525 intake / 0.525 exhaust
Camshaft Duration (@0.050 in.): 226° intake / 236° exhaust
Cylinder Heads (P/N 12629063): Aluminum L92-style port; “as cast” with 68-cc chambers
Valve Size (in.): 2.165 intake / 1.590 exhaust
Compression Ratio: 10.7:1
Rocker Arms (P/N 12569167 int): Investment-cast, roller trunnion
Rocker Arms (P/N 10214664 exh): Investment-cast, roller trunnion
Rocker Arm Ratio: 1.7:1
Recommended Fuel: 92 octane
Maximum Recommended rpm: 6600
Reluctor Wheel: 58X
Balanced: Internal

Thanks,
Perry
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Old 10-12-2017, 04:43 PM
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Or should I consider this motor. GM says it largely made for the drag strip. I'm looking for dumb, crazy RELIABLE power that I can get on it and cruise the hwys with.

Part Number: 19329009
Engine Type: LS-Series Gen-IV Small-Block V-8
Displacement (cu. in.): 376 (6.2L)
Bore x Stroke (in.): 4.065 x 3.622 (103.25 x 92mm)
Block (P/N 12623967): Cast aluminum with 6-bolt, cross-bolted main caps
Crankshaft (P/N 12597569): Nodular iron
Connecting Rods (P/N 12607475): Powdered metal
Pistons (P/N 19207287): Hypereutectic aluminum
Camshaft Type (P/N 88958770): Hydraulic roller
Valve Lift (in.): .525 intake / .525 exhaust
Camshaft Duration (@0.050 in.): 226° intake / 236° exhaust
Water Pump (P/N 12604630): LS3
Cylinder Heads (P/N 12629063): Aluminum L92-style port; “as cast” with 68-cc chambers
Valve Size (in.): 2.165 intake / 1.590 exhaust
Compression Ratio: 10.7:1
Rocker Arms (P/N 12569167): Investment-cast, roller trunnion
Rocker Arms (P/N 10214664 exh): Investment-cast, roller trunnion
Rocker Arm Ratio: 1.7:1
Recommended Fuel: 92 octane
Maximum Recommended rpm: 7000
Reluctor Wheel: 58X
Balanced: Internal

Perry
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Old 10-12-2017, 04:47 PM
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Hmm, I should have read the last post before posting. Seems the only difference is the water pump and higher rpm.

Perry
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Old 10-12-2017, 11:47 PM
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Quote:
Originally Posted by size-o View Post
Hmm, I should have read the last post before posting. Seems the only difference is the water pump and higher rpm.

Perry
go for the one with the 6600rpm max.
that looks like a great engine for a new one.
are you set on a paddle shifted tci 6speed auto
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Old 10-13-2017, 11:57 PM
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The paddle shifter is an option. The 6X comes standard with their outlaw shifter:

https://www.summitracing.com/int/par...1641/overview/

The two buttons on the backside of the pistol grip can be used for transbrake and nitrous, or, manual shifting. I did the research and it sounds like people have had issues with the paddle shift. Besides I think the pistol grip looks badass.

Perry
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