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8.1L factory intake mods, homebrew style?

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Old Dec 18, 2014 | 09:03 AM
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Default 8.1L factory intake mods, homebrew style?

Hello. First of all I love Raylar stuff. If I win the lottery I will have their heads/cams/intakes on all of the five 8.1l powered vehicles I will buy.

I might be modding another 8.1 soon. If I remove the intake, I want to do what I can to it. What kind of mods are done to the stockers? Is all the work done from the throttle body hole? Is the bottom of the intake touched? Ports?

Anyone have any details?

Thank you.
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Old Dec 23, 2014 | 01:46 PM
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you have 3 options.

1) pay raylar, which is proven and yes expensive, but nothing is free in life and he has the back up / research to prove his stuff, he is like gale banks of the diesel world.. ( yes i know i other people make more power than banks on diesel parts,)

2) buy the dart intake that is made for raylar, the drill it for injectors etc etc etc,

3) take you intake off, get a saw cut the bottom out of it, reweld it all and hope it works..

or try to make your own witch still falls in #3 category
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Old Dec 23, 2014 | 03:06 PM
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Originally Posted by Kerr
you have 3 options.

1) pay raylar, which is proven and yes expensive, but nothing is free in life and he has the back up / research to prove his stuff, he is like gale banks of the diesel world.. ( yes i know i other people make more power than banks on diesel parts,)

2) buy the dart intake that is made for raylar, the drill it for injectors etc etc etc,

3) take you intake off, get a saw cut the bottom out of it, reweld it all and hope it works..

or try to make your own witch still falls in #3 category
The first and third option are basically the same. You'll want to cut into your manifold and remove the interior sections which block flow, then smooth everything out. After that you'll want to take it to a fabrication shop and have their best welder seal everything up for you. Don't skimp on the last part, if the aluminum manifold warps, you'll develop vacuum leaks and your engine will idle at 2000rpm / will suck as much oil as it does gas.

The $500-$600 dart intake is a 4 bolt, efi plate / carb style manifold with a distributor provision. Its more made for eliminating the factory EFI system for old school swaps than it is for late model mods. You can adapt it with a carb to throttle body flange similar to carb lsx manifolds, but you're never going to make it past the smog ***** with it.

Hogan also makes a really pretty LSx looking manifold for the 8.1L. We don't offer it because they want more than our CoolGap manifold costs for it. It lacks a provision for an oil fill, so you'll have to custom make a set of valve covers to get oil into the motor.

The last (and worst!) option is to make your own. Aside from fitment headaches, a few people (paging EDxx) have made manifolds for these motors and with short runners, the engine drops a ton of torque.
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Old Jan 1, 2015 | 03:40 PM
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Thanx guys. Cutting the bottom of the intake off sounds crazy. I get the price.
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Old Jan 10, 2015 | 09:25 AM
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Yes dont go short runner.. unless it is boosted
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Old Feb 27, 2015 | 11:38 PM
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We seem to have the exhaust thing figured out pretty well, so now we're working on the intake system, from the fender to inside the manifold, and mebbie some outside too. TIMINATOR
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Old Feb 28, 2015 | 11:02 AM
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So I'm thinking about doing this mod myself. Does anyone have a stock intake they will part with that I can play with?
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Old Mar 1, 2015 | 10:57 AM
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And what do you do for the pcv system once its modified?
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Old Mar 1, 2015 | 10:42 PM
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You can drill and tap the "neck" under the throttle body for a 3/8" hose barb and run a hose to it from the rocker cover or intake manifold rear thru a PVC valve. You have to make sure to weld shut the old PVC hole up to the throttle body to make sure that you don't have a vacuum leak there. Some Mopar PVC valves have a hose barb on both ends. TIMINATOR
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Old Mar 2, 2015 | 08:49 AM
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Tim the passage through the front of the intake is a breather
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