Beast96Z

iTrader: (21)

I couldn't Imagine 4 LT-1 Tb's under a f-body hood. Depending on what size your looking to use, the Motorcycle TB's may be more sleek and easier to work with.

njn63

not sure how much this will help you, but there have been more than a couple people who have made their own individual throttle bodies for Hondas.
http://www.tuner-junction.com/TJForu...read.php?t=144
http://www.homemadeturbo.com/tech_projects/itb/

That's 2 really good writeups.

chuntington101

there is a bit of a craze starting over here (and i can see why) for using moptorbike carbs or throtle bodies on 4 cyclinder engines upto about 2.5ltr. the bodies seam to handle the flow no problem and four can diliver over 250bhp i think!

now on a BIG engine you are goiong to start running into the flow limits of the boddies very quickly! if i wehre doing it and wanted to use bike TBs id go for three banks of four (giving 12 TBs in total)! this way you will def not run out of flow through the bodeis anyway!

Thansk Chris.

xfactor_pitbulls

iTrader: (16)

That is too many for my taste. 4 is hard enough to link together, X 3 and you add even more problems. Think I will stick with 4 total, just need to figure out if there is another gm based car that would have tbs that make sense, and i bet there is.

Brandon

J-Rod

Ok, a couple of things. My buddies in Australia built ITB intakes before Harrop came out with the production model.

You can buy TB's from Accufab and others.

30MM is far to small. For an 8 runner ITB setup on an ls1 a small TB is 48MM, a medium is 50-52, and a LARGE is 55.

You ditch the MAF and convert to SD.

All the TB's are synchronized, so you only need on TPS input. So, you mount one TPS. Its probably easiest to reference off the linkage, or one TB.

As for an IAC. You can tune to not need one. If you really want one, work from the factory unit. Create a distribution block, and feed it from the ITBs. But I think you can get by without needing one

MAP - A must. You need to have a small hose coming from each TB, and feed a distribution block with your MAP sensor installed.

8TB setup
http://users3.ev1.net/~black_ops/AUS/dsc00025.jpg
http://users3.ev1.net/~black_ops/AUS/dsc00027.jpg
http://users3.ev1.net/~black_ops/AUS/dsc00028.jpg
http://users3.ev1.net/~black_ops/AUS/dsc00037.jpg



4ITB intake.
https://ls1tech.com/forums/generation-iii-external-engine/481985-finished-throttle-body.html

chuntington101

J-Rod, who builds the 8 TB set up?? any idea on cost??

thanks CHris.

xfactor_pitbulls

iTrader: (16)

I realize that you can buy the TBs anywhere, but just wanted to retain the GM IAC. Didnt realize you could do without the IAC.........thats good to know. Obviously the MAF was going to go anyways. I hear you about the MAP that was my most recent thought as well. I appreciate the input guys, this is the kinda thread that really helps people. Gonna start looking for TBs now, the easy one if the circle, I really think an oval would work better for what I thinking.

Brandon

MrDude_1

iTrader: (4)

since you ahve to tie in all the runners together for the MAP, i dont think its a big streach to connect the IAC to that "tied in" point..

xfactor_pitbulls

iTrader: (16)

Its alittle more complicated than just running a vaccum feed. I am all about simplicity, especially for the first go round. Obviously I could modify as well after it is done.

Brandon

FieroZ34

iTrader: (1)

Don't take this the wrong way, but did you read my post? I explained the idle thing. You can run it with no IAC, but I wouldn't suggest it, especially when it wouldn't be difficult to incorporate.

Also, it really isn't more complicated than running a vacuum feed from each TB, so long as the IAC lets air into the vacuum accumulator.

Idea: The LS1's IAC is incorporated into the TB. Now what if you cut off the rest of the TB, only leaving the IAC part, the inlet, the port, then the outlet. Then just weld, JB weld, or anything a pipe on each end? Stock IAC, stock wiring, etc. A cheap, easy to fab, accurate, reliable IAC valve. I may just do this on some cheapa** TB from like a GM 3.1 or something. Most GMs use the same inline 4 pin IAC connector, and runthe same IAC voltage, so you can use almost any model IAC too.

zuluman13

iTrader: (-1)

I am planning on building an itb for the motor im building. I have most of everything figured out except i havent figured out the best way to transition the round throttle body into the cathedral intake port style of the ls1 head the only thing that i could think of is a plate about an 1-1.5 inches thick and blending it. Does anyone have any ideas for this.

FieroZ34

iTrader: (1)

I'm in the same boat, just not as bad, I have to go from my circular throttle bodies to a rectangular intake port. Still havn't decided how I'm going to do that one...

cueball

You could just use an older style tbi IAC that physically moves the throttle blade to control idle.
hope that helps.

MrDude_1

iTrader: (4)

what TBI is this?

every GM TBI ive seen uses a standard IAC like all of the other cable operated throttlebodys have had..