Yes I'm coming from an ls6 with stock ported throttle body. Can't comment on how it runs because I'm having issues with it right now. The alternator isn't charging. Not sure it's inrake install related, I doubt it. So I'll be diagnosing that tonight.

 

So is it worth switching from my ls6 intake to a Dorman ls2?

 

Judging from the post directly above yours, we are about to find out....

 

Ok guys, I haven't posted back because I've had some issues with the car. Some intake related, some not. Let me get the intake issues out the way. When you put one of those China throttle bodies on, the throttle gets real stiff. Not fun to drive and I hate getting out of my 2017 silverado and into this car and having to get used to the hard throttle. So what I did was I had an old ls1 throttle body that I grinder the shaft down and stole the spring off. It fit perfectly. Didn't make a damn difference. Lol. So after looking at it for a minute, I noticed the spring position was where it wound the spring tighter. Dangit. So I ended up drilling another position for the spring to match the stock position. Now omg omg the throttle was so light I couldn drive it. Kinda funny but dangerous because thee was no easy or smooth take off. So now I'm like wtf. Then it struck me. It's two springs wound into each other, I rotated one of those springs to the tighter position and voila! Feels exactly like stock. I forgot to add in there that I ditched the stock springs and used the ones that came with the throttle body.

You can see where I drilled the hole. Notice the scribe line.



Next I was having trouble getting wide open throttle. I thought it was the spring being too stiff at first and causing the traction control unit (long story short the cable runs through it on some cams and it was slipping) to not pull the throttle open but to 80%. The real culprit was the throttle body linkage arm hitting the intake. Look at the end of the screwdriver, I had to grind it a touch there and that did the trick. I may have mentioned this before, but make sure on these china throttle bodies you LOCTITE the throttle blade screws! I think mine would have come loose because they really weren't tight.






Now for the answer you've all Been waiting for. Is it worth the swap? My honest answer right now is I'm not sure just yet. I was out dialing in my afr's earlier tonight and it's running 10.-11.xx in the 3000-4800rpm range and 12.5ish from 5200-6400. I'm working on getting it leveled out but I ran out of time tonight. It does seem to pull as hard as the ls6 intake with it running rich like it is right now. However, dead stop stomping it without stalling results in no tire spin and before it would spin a couple feet. I think it's too lean down low so I'll add more fuel and update after. It seems like it's not as flat in the midrange even though it's rich. I think (well I'm hoping!) that once I get it dialed that the car will be a touch noticeably faster. Keep in mind my engine doesn't even have a cam yet. All I have is a tune, xair ram air intake, high flow catted mid pipes on stock manifolds and a slp exhaust. I'm sure if the intake flows better then it'll shine with more mods. Stay tuned

 

Yep. I covered the throttle rotor hitting the intake in my write up. I had to notch out that area. My gas pedal was noticeably stiffer as well with the warr 92. I got used to it. No big deal.

I noticed a nice gain in the mid and upper rpms coming from the ls1 intake. I really believe the Dls2 falls somewhere between an ls6 and a fast 92.

 

Ok, I rode around a little bit tonight. I leaned it out some more. Not quite perfect but closer. I feel pretty certain that it pulls a decent amount harder through the gears except below 1500-2000 Rpm. I'm not sure I have the afr dialed in good enough down low just yet. Stock stall, and I don't have a way to log afr accurately right now. I cheaper out when I bought hp tuners and didn't get the pro, I do have a logger that I just ordered the cable to interface it with my wideband a couple days ago. I'll get it dialed in better then. I don't have any dyno or track runs so just take this for what it's worth. Also my trans is starting to slip on the 1-2 shift so I feel like it has to be making more power. The 2nd gear kick down at 45mph pulls significantly harder. Before the intake it felt like I was waiting forever for it to get to 55-60 and then it started pulling. I'm not going to lie, at first I was regretting this swap because it felt no faster, if not slower. Now I'm not feeling that way anymore. In my opinion you can't really feel 10hp but you can feel 20ish hp. I can feel the difference, is it 20hp? I dunno, but it's noticeable. I'll do a video for you guys if your interested, I have a before video that I did right before. You can see the tach and speedo moving faster.

 

Not sure if this has been posted here yet, but actual flow bench info regarding this intake compared to others taken from another forum.
I'm very much so considering this intake for the money!

 

Why does the LS6 have better #'s then the Fast ?

 

The LS6 numbers are for the HEAD, not manifold, to show max flow potential for any manifold used.

 

Well I finally got to drive the car today. It stopped raining. I'm getting my shift points lined out better and my down shifts tweaked. Do note that when you install a much larger throttle body that all of that changes because your getting more air in the motor sooner so it's like 40% throttle at 20% throttle (guesstimate). What happens is say your pressing the throttle 20% to briskly accelerate, you'd normally be pressing it 40% so because your pressing it less but outputting the same power, it shifts earlier causing it to feel lazy. Also when you go to pass someone you big the motor trying to get it to kick down. Just wanted you guys to be aware of that. Some people don't think about that but your tuner can fix that for you. It's not undrivable by any means, it's just not as lively and responsive as stock until the tune is corrected. I did get my afr much closer to where I want it and it does run harder than the ls6 intake.....which I'll have for sale shortly.

 

I have a 5.3L with a 224/228 cam and a LS6 intake. Would it be worth it to switch from my LS6 intake to the Dorman LS2?

 

Does anyone know if this is just a simple bolt on replacement for an LS2 GTO?

 

from what i gathered its direct replacement for ls1 for ls2 i belive younwould need different fuel rails

 

It has adapter brackets that work with the ls2 rail spacing also

 

This is not a good comparison, head to head match up car intake vs oem truck intake. The OEM truck will have lower flow numbers but in most cases produce more power than comparison car intake. Due to their design they make more power per cfm than car intakes.

 

I think you need to read that article. The entire point of Hot Rod using some many intakes were to eliminate any false statements and do as close to a direct comparison of intakes as possible. The TBSS intake performed better than any OEM cathedral port car intake.

 

Yeah Joe69z28, that was actually the point, and it might have taken the testers by surprise that the truck intakes did as well as they did. All in all a very fair test.

 

I'm sorry for the bad news but I just got an email from rock auto saying this Dorman 615-901 intake manifold is out of stock and has been discontinued. I sent an email to Dorman asking if they are making revisions and planning to bring it back with a new part number. No response from Dorman as of yet.

Can anyone else confirm this?

 

Back order 2 weeks not discontinued

 

Thank you for clearing that up WS6store! I wonder why rock auto would say it's been discontinued. When you're able to get your hands on more please let us know!