[SammYyYyY]

Hey all!

Soon I’m going to be installing a set of 1 7/8” Kooks longtubes, a Corsa Xtreme+ system (midpipe and axle-back), and a Rotofab Big Gulp intake on my 2018 ZL1 1LE. I was wondering if anybody had any insight as to what throttle body I should use.

My local shop (who will be installing and tuning the car) said that they can port the blower snout so we can fit a 103mm TB on there; my concern with this is that I won’t see much of a gain from porting just the snout and not the rest of the blower. Is this the case?


I could also do the classic LT5 + adapter plate; if I do this, will I see any real performance gains?

I’d love to hear anybody’s insight. Thanks!

[Laidoffsick]

I went with the Soler Performance ported LT5 with adapter plate since I did not port my blower. I have 2" LHT from CSP (made by Kooks), DSX Flex Fuel, and the Big Gulp Intake. Down the road I may have the blower ported and go with a 103 or 112 TB, but for now with the mods I have, the LT5 was more than sufficient.

Personally I would not port just the snout for a bigger TB.

[CalgaryZL1]

Originally Posted by Laidoffsick

I went with the Soler Performance ported LT5 with adapter plate since I did not port my blower. I have 2" LHT from CSP (made by Kooks), DSX Flex Fuel, and the Big Gulp Intake. Down the road I may have the blower ported and go with a 103 or 112 TB, but for now with the mods I have, the LT5 was more than sufficient.

Personally I would not port just the snout for a bigger TB.

This 100%

[SammYyYyY]

Gotcha! How much of a gain would I see from using something like a Soler 95mm throttle body with an adapter plate vs. just using the stock throttle body with the Big Gulp?

[Z OH 6]

Originally Posted by Laidoffsick

I went with the Soler Performance ported LT5 with adapter plate since I did not port my blower. I have 2" LHT from CSP (made by Kooks), DSX Flex Fuel, and the Big Gulp Intake. Down the road I may have the blower ported and go with a 103 or 112 TB, but for now with the mods I have, the LT5 was more than sufficient.

Personally I would not port just the snout for a bigger TB.

Actually CSP headers are made by Stainless Works unless that's changed in the last year or so.

[Z OH 6]

Originally Posted by SammYyYyY

Hey all!

Soon I’m going to be installing a set of 1 7/8” Kooks longtubes, a Corsa Xtreme+ system (midpipe and axle-back), and a Rotofab Big Gulp intake on my 2018 ZL1 1LE. I was wondering if anybody had any insight as to what throttle body I should use.

My local shop (who will be installing and tuning the car) said that they can port the blower snout so we can fit a 103mm TB on there; my concern with this is that I won’t see much of a gain from porting just the snout and not the rest of the blower. Is this the case?


I could also do the classic LT5 + adapter plate; if I do this, will I see any real performance gains?

I’d love to hear anybody’s insight. Thanks!

I would have used 2" headers for starters on a LT4, 1 7/8" are good for an SS though. As for the TB, it's worth porting the snout and using a 103mm as long as you're going to port the blower at some point in the future. I certainly wouldn't pay for an LT5 TB only to port the blower later and wish you had bought a 103mm, then needing to sell the LT5 TB. The gains from a LT5 TB would be so minimal anyway. I say either don't buy a TB at all, or port the snout and go 103MM so that you only buy once when you port the blower later or use a different blower.

[SammYyYyY]

Originally Posted by Z OH 6

I would have used 2" headers for starters on a LT4, 1 7/8" are good for an SS though. As for the TB, it's worth porting the snout and using a 103mm as long as you're going to port the blower at some point in the future. I certainly wouldn't pay for an LT5 TB only to port the blower later and wish you had bought a 103mm, then needing to sell the LT5 TB. The gains from a LT5 TB would be so minimal anyway. I say either don't buy a TB at all, or port the snout and go 103MM so that you only buy once when you port the blower later or use a different blower.

Gotcha. I went with 1 7/8” because I got a screaming deal on them; $600 with the catted connection pipes.

[Z OH 6]

Originally Posted by SammYyYyY

Gotcha. I went with 1 7/8” because I got a screaming deal on them; $600 with the catted connection pipes.

Oh well, sometimes its hard to pass up a good deal. They will still make more power than the stock manifolds.

[Booher]

Csp did change manufacturers, I asked him, but didn't ask why. Kooks is making em with csp now, it's no longer stainless works/power

[Z OH 6]

Originally Posted by Booher

Csp did change manufacturers, I asked him, but didn't ask why. Kooks is making em with csp now, it's no longer stainless works/power

10-4. I wonder if they're still the same design as the Stainless Works headers or if they're just rebranding Kooks design.

[radz28]

IMHO - if you haven't done so already, I would consider creating a powertrain plan for the car. It's silly to spend money twice (or more) for the same thing, so "buy once - cry once". If you know you have a goal, of say 1000 HP, I wouldn't spend money on anything else but a 103, especially if you know if you're going to stick to the 1.7 (or move up to any of the other PDs out there). Even if you were sticking to optimizing the current set-up, it's been proven a 103 is the best bet (an example off the top of my head was a Fasterproms YT video on Formatos wife's 'slade), especially because PDs move air best with the minimal inlet restriction, so if you're going with a BG, which requires a tune, spend the extra money on a 103, and make the best use of the BG. You'll be future-proof'd with the 103, until you start moving past 1000, and then should probably look into a 112 or something.

There are plenty of posts and threads on bang-for-the-buck, for what you're asking about. As seen many times: port the 1.7, 103/BG, LTs, and E', and you'll lose nothing in efficiency and move closer to a completely optimized bolt-on set-up with no additional heat. You might consider a low-side to run full E', but you can probably run high enough content that it's worth it.

[2023_ZL1-AUTO]

Congrats on starting your mods! I regret, with my mods that I just jumped in not really knowing what I should have known. I didn’t make an overall plan and just pieced it together from this and that I picked up that others did. I started ordering parts that I thought I’d want and needed, but know knowing my end goal. I guess it was I wanted faster and more power than stock and a car when people heard it, they knew it had mods done to it. I think if I would have planned it out, I could have of work backwards from there and make sure I did the right parts/mods. I made some mistakes along the way, a few costly ones. For instance, I bought a CAI Elite carbon fiber intake, great cold air intake, but not if your throttle body requires an adapter because you didn’t port your supercharger. So, after the parts were not working correctly, I bought a Roto-Fab Big Gulp, so the CAI was $1,000 down the drain. But I knew at the time I wasn't porting my supercharger, because I had no desire to take it off the car. Then, two different catch cans later and a broken off supercharger stud. I had the blower off a total of 4 times. So, any one of those times it was off, I should have just boxed it up and sent it to get ported. After it was all done, I probably should of went with 1 7/8" long tubes vs 2". I went with CSP long tubes by Stainless Works, I love these headers! They fit like a glove and were easy to install. But take the advice above and my advice, plan it all out first is a wise move!

Here is my build thread for reference!

https://www.camaro6.com/forums/showthread.php?t=611982

Good luck and keep us posted !!!

[SammYyYyY]

Originally Posted by 2023_ZL1-AUTO

Congrats on starting your mods! I regret, with my mods that I just jumped in not really knowing what I should have known. I didn’t make an overall plan and just pieced it together from this and that I picked up that others did. I started ordering parts that I thought I’d want and needed, but know knowing my end goal. I guess it was I wanted faster and more power than stock and a car when people heard it, they knew it had mods done to it. I think if I would have planned it out, I could have of work backwards from there and make sure I did the right parts/mods. I made some mistakes along the way, a few costly ones. For instance, I bought a CAI Elite carbon fiber intake, great cold air intake, but not if your throttle body requires an adapter because you didn’t port your supercharger. So, after the parts were not working correctly, I bought a Roto-Fab Big Gulp, so the CAI was $1,000 down the drain. But I knew at the time I wasn't porting my supercharger, because I had no desire to take it off the car. Then, two different catch cans later and a broken off supercharger stud. I had the blower off a total of 4 times. So, any one of those times it was off, I should have just boxed it up and sent it to get ported. After it was all done, I probably should of went with 1 7/8" long tubes vs 2". I went with CSP long tubes by Stainless Works, I love these headers! They fit like a glove and were easy to install. But take the advice above and my advice, plan it all out first is a wise move!

Here is my build thread for reference!

https://www.camaro6.com/forums/showthread.php?t=611982

Good luck and keep us posted !!!

Thanks man! Great advice and will do!

If you don’t mind me asking, why do you say you think you should have gone with 1 7/8” headers instead of 2”?

[The drive inside]

Originally Posted by SammYyYyY

Hey all!

Soon I’m going to be installing a set of 1 7/8” Kooks longtubes, a Corsa Xtreme+ system (midpipe and axle-back), and a Rotofab Big Gulp intake on my 2018 ZL1 1LE. I was wondering if anybody had any insight as to what throttle body I should use.

My local shop (who will be installing and tuning the car) said that they can port the blower snout so we can fit a 103mm TB on there; my concern with this is that I won’t see much of a gain from porting just the snout and not the rest of the blower. Is this the case?


I could also do the classic LT5 + adapter plate; if I do this, will I see any real performance gains?

I’d love to hear anybody’s insight. Thanks!

It's beneficial to port the blower with the snout...you have to port the snout for a 103mm throttle body! Stock setup with a ported blower is maybe 30whp gain...E85/boost/Colder plugs is what these cars love!