Finishing up building my LQ4 and need to find an intake that will work for me. The motor is an LQ4 with flat tops, milled 317's, summit cam 222/232. It is going in a truck with 4.88s, 4l80e, and 35s or 37s, so I need to keep low end power in mind. I have a truck intake that I could use, but I feel like I may as well upgrade it since everything else is new. My initial thought was TBSS with a 90mm tb, but as a priced it out, it will end up costing a lot more than just a "cheap" upgrade. So then I looked into other options since I'd be spending a decent amount anyway. Here's the one's I'm interested in:

1. Sheetmetal/Fabricated Intake
https://www.summitracing.com/parts/sum-226127?rrec=true

I've heard very mixed things about these and am wondering if anyone has any first hand experience with these.

2. Speedmaster LS intake
https://www.jegs.com/i/Speedmaster/7...8-032/10002/-1

Looks similar to an ls6 intake but haven't head much about it at all.

3. Vic Jr. Carb Style intake (not sure which tb would be used)
https://www.jegs.com/i/Edelbrock/350...hoCxn0QAvD_BwE

This only peaked my interest because it would give me the old school look and is somewhat affordable. Really not sure how this would perform on the low end.

4. TBSS

I would shave and paint this intake, and when all is said and done, I feel like I could have just bought one off the shelf for less hassle.

I really do not want to spend crazy $ on an intake as this is a pretty mild build. Anything like a Fast LSXR or similar is out of the question lol. Let me know what you all think. Thanks

 

On street tires, you will run out of traction before you run out of airflow from the stock plastic truck manifold.

 

Three of the four intakes listed will hurt low end torque vs the stock intake. I'd keep the stocker or move to the TBSS out of the choices listed. Sometimes used TBSS show up for ~$250 with injectors & fuel rails in marketplace.

 

As Blackbird said, your only good choices are the TBSS or (I believe) stock LS6. Stock truck intakes are also acceptable.
With the first 3 intakes your low end WILL get soggy. They are looks-only manifolds.

 

Thanks guys, that's kinda what I figured. Now my next question is this: is the tbss intake a significant step up over the truck intake? I know this topic has been beaten to death, but as I'm pricing it out, it'll probably cost ~$400 to run the tbss aliong with a bigger tb. I don't mind spending the money to do it right, but is that 10-15 rwhp gain going to be noticeable?

 

This is an older yet good aritle on cathedral intake manifolds with lots of engine dyno testing.

20-ls1-intake-manifolds-tested


This is the graph of the truck intake.



This is the TBSS intake on the same engine.

The TBSS is definitely better.

However seat of the pants feel, in a vehicle with gears, down low as mentioned above by another member, I think traction would be more of an issue and one wouldn't feel much (any) difference under 3,000 rpm.

Passing on the highway the TBSS you'll probably that extra average of 15 foot pounds more of torque (3,000 to 7,000) and peak of 20 foot pounds more depending on how far one winds the motor based on the graph. Similar story with hp.

 

Another vote for tbss . new gaskets and port the throttle body and it'll provide everything your after.

 

TBSS or you will be disappointed

 

TBSS manifolds can be purchased BRAND NEW on Amazon for $115.. Just laying that out there. I would caution you on which after market throttle body you buy.. There is a LOT OF JUNK out there... Like MORE JUNK than quality. Nic Williams is the way to go. I have personally wasted money on a Fi Tech 92MM that was TRASH right out of the box and nothing I could do would make it work as it was not engineered properly. The air feed hole cavity for the IAC was TOO SMALL and would NEVER allow a stable idle regardless of what I did in the tune. Learn from my mistake. If you are wanting a quality, bolt-on and go TB---Nic Williams is the way to go. There may be others out there that work.. But I've heard that the Holley and several others are just as bad as the FI-CRAP. Personally.. if I had to do it again, I would just run the TBSS intake, and an adapter to use my GM original DBC TB... Yes, I know it's only 78MM.. but have you seen how much power can be made with the factory TB? It's MORE THAN your engine is going to make so it will not be the choke point you think it will be. In short.. Buy the intake manifold-but keep your original TB as the "looks" or "performance" you think you are getting with the after-market TB will never materialize on a mild build like yours.. An after-market TB on your set up is probably just wasted money. Don't forget the tuning you will have to do.. If you think tuning for a larger TB is easy... welp... you might better go and do some reading on the subject... If you are paying someone to tune it then that won't really matter tho.. Sounds like you have a solid build.

Is there a reason you stayed with the 317 heads? The popular thing for more "free" horsepower is to run heads with smaller combustion chambers to get higher compression, and more hp and torque. I'm running ported 706's on my 370CI LS... I can tell you it was a drastic improvement over the 799's I had on there previously.

 

The GM engineer who made the TBSS intake had a nice sharp pencil that day.

 

Thanks, really appreciate the info. I think you’re right on sticking with the stock tb. I stayed with the 317s because I had them already and didn’t want to put out for 243s or similar. Whatever heads I was going to use, I wanted them cleaned up and a valve job done so I figured I could just shave off.030 off the 317s for really cheap and make some decent power with them. This motor is going in a 62 k10 so it doesn’t need to be a race car lol. We’ll see how these heads perform.

 

If doing the TBSS, its only ~$150 for a very high quality 92mm TB.

WARR Performance has Nick Williams quality TB's for about half the cost of the NW. Have an NW 92 on my 91 RS and a WARR 92 on my 02 Z28. Quality is basically equal. With the WARR you'll need to reuse the old 78mm TB's sensors. New ones are like $80 from Summit.

 

I have a TBSS intake/rails, with Corvette LS2 injectors and a 92mm WARR TB on the LQ4 in my GMC, been on for 3 years, very happy with it. I have 4.56 gears and a 3200 Yank, there's no concern of being soft below 3000 rpm, as that range doesn't exist.

 

I got a new tbss intake for $90 and will probably stick with stock 78mm tb for now. I want the intake to look clean and factory, and I'm wondering if anyone here has made the lq4 fuel rails work on the tbss? I have read a couple threads where people have done it but there is not a lot of info. I know I would need to extend the crossover pipe and rig up some sort of spacers. The main reason I want to use these rails is to retain the return style system on my truck. The corvette filter looks pretty bad imo, and am hoping I can come up with another solution to avoid using that.

Another idea - use tbss rails and change the fuel pump to an 05-06 truck pump which is returnless I believe. However, I'm not sure if this fuel pump would be plug and play

 

When I put a TBSS intake on my 00 LQ4, I used the stock fuel rail (to keep the non-flex fuel fuel pressure regulator) with the (slightly taller) L59 flex fuel injectors and the crossover from the flex fuel rails.

The flex fuel crossover is different than the regular crossover. Not sure why GM did this since the gen3 flex fuel engines had the same early truck intake. The flex fuel fuel pressure regulator is also a completely different size that the non flex fuel FPR and operates at a slightly lower fuel pressure.

I had to trim the mounting tabs on the fuel rails (where you bolt the fuel rail to the intake) and drill new holes, but it works.