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I have a 79 that I'm doing a frame off on. The motor I had built at my buddies shop and he has steered me into some sunlight but I still need a little help. Its a beefed up ls1 6.0 with ls3 heads and a ls9 blower, classic air a/c, the 1st ls9 assessory kit from cvf racing, tanks inc fuel pump, holley dominator efi harness. Have a rebuilt 4l80 trans but cracked it and need a core to swap internals. Ive seen threads that talk about the swap but are like 10 years old and a guy I saw that did the ls9 swap wont answer me on youtube. my questions are:
1-what cold air intake have yall found to work?
2-can I use my surface pro 4 with the holley system to tune
3-anybody in GA have a 4l80 core I can swap my internals 2
4-how did you guys run exhasust
5-how do I hook the vacuum up for the headlights
6-if you have done an ls9 swap please contact me I have a million questions that I will post.
also I will post pics as I go along to help the next guy finish without looking like an idiot like I am
 

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DC PIT CREW BOSS
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The only one I can help with is #5. You might want ot consider changing to electric. There are several threads here on the conversion
 

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There will be excellent full time vacuum at the throttle body.

If you don't have ports between the throttle body and blower.......A lot of other supercharged applications still hook vacuum accessories to the normal spots downstream from the blower. There's still vacuum up to around 20% throttle. Use a check valve in the line and the headlights should work fine.

good luck!
 

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I'm doing an ls3 swap now. Sounds like you've already dug around some but be sure to keep in mind control arm clearances around the power steering pump/alternator and water pump sides. I say that because it looks like the accessory setup you have moves the alternator and power steering lower because of the throttle body angle.

Here's a link to my ls3 swap if you haven't seen it foraccessory reference pictures and also for you classic auto air install. They sold me some universal kit that did not universally fit on my later c3 knowing some of the install is very very similar to the earlier c3's.

http://www.digitalcorvettes.com/forums/showthread.php?t=283297

1. Most just do a filter setup in the engine bay. Some will end up building a custom setup or go so far as to going to a different size radiator to get cool air from.
4. Sidepipes here. Patro just did some hunting for headers. Some of it depends on you steering setup. Some just keep the factory manifolds and route new pipe to the back.
5. I think you'd enjoy the electric motors better, but ls swaps aren't cheap either so like said above, hook up to engine vacuum and add/replace check valve.
 

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#1. I routed my tube down and put a cone shaped filter on in front of the MAF. I made a housing that surrounds it and draws air from below the radiator. I tried to over size it as much as possible to limit restriction, but don't have any way to measure that. I did, however, put the outside temp. sensor on my Dakota Digital gauges behind the radiator where the cone filter was formally located. I compared that to the ambient air temp on my ECU readout via a bluetooth dongle running into my iPhone. Before startup the temps were about identical. I watched the difference as I drove around and it did make a huge difference. The biggest seems to be when I was on the highway and then slowed down in town. The difference was a full 60 degrees. It was less on the highway but still very significant. I forgot to take pictures when I was building the box out of fiberglass, but took some as well as I could once installed.
I had to add a tab on the spreader bar bracket so it could be moved toward the engine and open a little more room to pass down.
IMG_5308 by brent hagist, on Flickr
IMG_5310 2 by brent hagist, on Flickr
IMG_5311 2 by brent hagist, on Flickr
 

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I've brought this up before, but it bears repeating. When your searching for a cold air alternative on an LS swapped C3, you already know there isn't an easy solution, by any stretch of the imagination. What you might not know, unlike any carburated version of an engine, the fuel injected LS has a handful of sensors, one of which is an IAT sensor. It's job is to measure intake air temp. No big deal, right? Wrong. The IAT sensor has a table on the pcm that takes intake air temps and scales the engine timing to match. Yea....so?
Most folks put a 90 on the throttle body and toss a cone filter on it because...it works.
Sort of anyway. Here's why, but first a question.
When your cruising around on a hot summer day (or any day for that matter) how hot you think your underhood temps run? Toss that number around in your head then realize that iat table starts pulling engine timing when the iat's hit 130 deg or so.
The reason nobody seems to care is the engine still runs...ok, because the timing is being pulled in the background and most havent a clue its even taking place...but it is. I didn't know it was happening until I hooked up HP Tuners and began recording logs. I was exceeding 150 deg iat's with a 90 and a cone filter with the pcm effectively pulling 5 to 6 deg from the engine timing. Keep in mind this was before the LSA blower install when it was basically an LS3. Now, more than ever keeping the iat's cool has become a project, having to shrink the horizontal dimension of the radiator to allow room for a 4 inch cold air solution to draw from in front of the radiator/condenser/supercharger heat exchanger.
I did it, but it was a pain, and a newer design is currently in the works.
 

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Spot on Pat! I wish I had addressed this before the car went back together and painted all pretty. I think there's a way to get the filter over the radiator depending on what radiator is used. I have a gap between the radiator and the support. I'm thinking if you channel an area you might be able to go over. That's what Winter is for..
 

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Spot on Pat! I wish I had addressed this before the car went back together and painted all pretty. I think there's a way to get the filter over the radiator depending on what radiator is used. I have a gap between the radiator and the support. I'm thinking if you channel an area you might be able to go over. That's what Winter is for..
I can see this as a possibility in an FI NA engine, because the throttle body is positioned in the center.
With my LSA, it has around a 33 deg bend to the drivers side, pretty much leaving the drivers side to deal with the solution. Josh at Custom Image Corvette had the idea I began with-shrinking the horizontal area of the radiator. I also had to shrink the condenser as well as the front mounted secondary supercharger heat exchanger. This at least can get you in front (or to the side) of the radiator for a cold air solution.
For a straight LSx application, I agree going over the top, even if you had to notch the radiator support and shink the vertical area of the radiator
 

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Discussion Starter #11
Update
Finally got around to working on it. Got the gas lines ran(gotta mount the regulator on firewall)
Heater hoses barely cleared the control arm but there clear
Power steering and alternator side has plenty clearance
Trans mission lines ran
Put coil packs and spark plugs in
Thermostat housing in
Body goin back on next week after I finish a few other odds and ends
 

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heres my cracked transmission
If you have the broken piece yet I would TIG Weld the transmission case back together.
The trick is to preheat warm the area up with a MAP Gas blowtorch.
Heat it to 300 F. Check with an Inferred Pyrometer temp gun.
Then TIG Weld on the outside & inside of the Bellhousing.

Hold the piece in place with a nut & bolt with washers or flat stock steel.

4L80E transmissions are out there if you want another trans case.
They have lost popularity except for the Pro Touring groups.
 

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As long as your not severe drag racing the welded 4L80E trans case will hold up.

It looks like the trans was hanging by the bolts initial instead fully seated on the engine block dowel pins.

All GM transmissions have this weak area. The Bellhousing.

The GM TH400 Turbo 400 has the strongest beefed bellhousings.
 
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