Dorman ls2 intake?
#303
TECH Senior Member
#304
TECH Veteran
iTrader: (1)
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
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
#305
Launching!
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.
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.
#306
TECH Veteran
iTrader: (1)
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.
#307
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!
#309
TECH Senior Member
The LS6 numbers are for the HEAD, not manifold, to show max flow potential for any manifold used.
#310
TECH Veteran
iTrader: (1)
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.
#315
On The Tree
Join Date: Oct 2011
Location: Dirty South
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I'm really on the fence about the dorman ls2. After doing some research it seems like it *may* not be worth much more than 5hp at the flywheel over an ls6 intake. Here's my logic:
So we all know the tbss and the dorman flow very close to the same. The dorman beats the tbss in the low lift ranges by a very small amount and the tbss beats the dorman past .550 lift by a small amount. Ok. Then there a dyno test and the tbss beats the ls6 intake by 5 peak hp and 14tq. Flow isn't everything however but I think this is a decent indication of the hp difference the ls2d may be over a ls6 intake. So as it looks right now it might be the best bet to skip the dorman and get a fast 102. Do it right the first time kind of thing.
Here's some data from the magazine test.
Tbss intake Ls6 intake
Max hp 562 557hp
Max tq 497 483tq
Avg hp 444 432
Avg tq 464 450
Tq @ 4000rpm 469.5 454
We all know the tbss intake is going to make more tq too. Just my .02 until someone else can dyno prove other wise.
So we all know the tbss and the dorman flow very close to the same. The dorman beats the tbss in the low lift ranges by a very small amount and the tbss beats the dorman past .550 lift by a small amount. Ok. Then there a dyno test and the tbss beats the ls6 intake by 5 peak hp and 14tq. Flow isn't everything however but I think this is a decent indication of the hp difference the ls2d may be over a ls6 intake. So as it looks right now it might be the best bet to skip the dorman and get a fast 102. Do it right the first time kind of thing.
Here's some data from the magazine test.
Tbss intake Ls6 intake
Max hp 562 557hp
Max tq 497 483tq
Avg hp 444 432
Avg tq 464 450
Tq @ 4000rpm 469.5 454
We all know the tbss intake is going to make more tq too. Just my .02 until someone else can dyno prove other wise.
#316
TECH Fanatic
iTrader: (27)
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.
#317
TECH Senior Member
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.
#318
Discontinued!
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?
Can anyone else confirm this?
#320