I know this was discussed a few years ago but has anyone replaced the throttle body? Anyone know the size of ours? I think its 75mm. I was going to put on an ls6 tb but i believe its the same size?

 

everything I've read says its a 75mm TB

 

The '08s also have a different pin connector from the others, be wary.

 

I believe its referred to as a 78mm.

 

76.2mm bore and 82.55mm inlet that tappers down to 76.2mm. These messurements are outside diameters.

I was searching for a adaptable tb and called a bunch of shops. I was told to use the C5 Z06 TB or any TB that does not use a external TACH.
The ZO6 TB's pinning is different, but the voltage reference points are simmular.

Using the ZO6 TB would eliminate the TB adapter and add a few more hp up top. Plus you could step up to the larger 85mm MAF and tubing.

For people wanting to do this swap.. I have not tried it and do not know for sure if the LS6/Zo6 tb will work!
The Zo6 85mm MAF will work (Re-pinning) but rquires funky pipe reducers due to our small *** TB inlet. Using the Z06 TB and MAF with the right size filter and tubing would be the right way to go. Expensive and un-proven, so use at own risk!

I would rather use the TPiS 90mm LS6 intake with a LS2 TB and LS2 MAF. Search for answers I have this setup all over the place!

 

And for the record.. even the new 5.3 trucks are using 90mm tb and such now.

 

I am using a 78mm ls6 intake now. I will probably do a 85mm tb, tubing and maf. The shop is still looking into the details though on it. I will let you know! Thank you David.

 

how big is the z06 tb you are referring too?

 

76mm, but the inlet that the inake piping connects to is bigger. We have V6 piping.

You can get a bigger TB for the LS6 intake. They are billet and cost over 400.00

 

ok thanks, i will let you know what my shop decides to do. They were the ones who rigged up the ls6 intake to look stock so they should be able to do a great job. Fingers crossed for some serious top end hp gains

 

Cool.
You have been a true LS4 pioneer. Even though I'm a hands on guy, I have been a fan of your build. Keep it up!

 

yea man you have steadily become my rival lol You took my chance to be the first to break into mid 12s!!!!
I appreciate the help hopefully this one last push to do something new will prove to be worth it. Lets hope i gain like 30hp up top or something lol
Hey maybe we will be able to show that the ls4 can hit 11s NA

 

 

that would be cool!

 

And then top it with boost to get to low tens, maybe even nines. God, I wish I had the money. I would do it in a heart beat, lol.

 

So no go on the throttle body. They used a c5 Z06 maf and tb. They got everything installed and physically working but they weren't able to get the computer end of it to work. Apparently the computers are too different.

I did tell them that the new 5.3 trucks use the larger 80mm tb now so they are going to look at that route

 

The truck one is closer to 90.

 

Also your intake opening is only 75-76mm. So there is no point in upgrading to a larger TB.

You should send your intake to TPiS and have them plastic weld a LS2 inlet. Then you could use a LS2 90mm TB. The costs is 350.00. http://tpis.com/parts/view/39
The 799 is for a intake and the LS2 inlet upgrade. Call them and they will mod your intake.

LS2 Inlet, TB, and MAF!

 

The problem is the wiring doesnt match. My mechanic was saying they use different resistances on the c5 z06 tb.

I am trying a few other things. Like i said they got it all installed and stuff so the fit wasnt a problem. It was just trying to get the motor to work that was troublesome

 

Of course everything fit. That TB is for that manifold lol.
Seriously, send that manifold off to TPiS. I have been wanting to do it for a long time!