Generation IV Internal Engine - Worth swapping to a different vvt cam?

Im running a tsp vvt-2 cam in my ly6 since thats all that tsp had as far as vvt cams were the ones for the camaros. Now i see that they make 4 cams for l92 and im guessing ly6. The largest is mid 220 duration and is for aftermarket heads says their site which is around what my vvt2 cam is. Wondering if it would be worth getting a cam for the truck engine instead of the current l99 one? Emailed tsp and got the response on it wouldnt make a difference.

Why are you looking for a different cam? It could be the tune. Also, noone really makes cams just for our Ly6. The LS3/L92/L99 cams should be close.

"The largest is mid 220 duration and is for aftermarket heads says their site"

They also make a VVT3 camshaft that is around the 230-231 duration range. The above poster is correct regarding which motors these cams will fit.

As I suggested if your build thread, you should really degree your cam since it sounds like you have a mismatched core and phaser. The phaser table in the tune also is relative tithe degreeing so you may be leaving a lot of power on the table. (will also give you the chance to replace that TTY phaser bolt you reused.. ;) ).

The truck vs car VVT cams is mostly about getting more TQ and matching the cam to the intake since trucks use the larger and longer runner intake.

Ill have to ask tsp about the degreeing since they are supposedly on different cores. Tsp has tuned several ly6 trucks with the vvt1 and 2 cams so i would think theyd give me a heads up that the cams are positioned differently and need to be degreed to put it in the correct spot. My truck still hasnt been on the dyno so i dont know how the power curve really is and from the feel hopefully all that is needed is a tune. It cruises just fine around the city and highway in the lower rpms 1500-2000rpms but in first gear take off theres a very noticable power increase after say 3500 maybe higher which is fine rowing through the gears since shifting at 6500 puts the rpms back at 4500+. If i take it easy at the launch on street tires so that it doesnt roast them off the line and then get on it it will be fine until the higher rpms then the tires will break loose. Thought vvt was supposed to spread out the power more? Its just tuned by me so that could be the reason haha.

Let us know what you find out from TSP.

I will.

I would invest a few bills in a reputable tuners shop, before I tore back into it.

Called tsp about the cam and they said that they grind it on the core according to what phaser p/n I have. Thats why they ask what phaser I had when I ordered, for the correct phaser limiter and core. So I should be good. Going to get it tuned end of this month.

Called tsp about the cam and they said that they grind it on the core according to what phaser p/n I have. Thats why they ask what phaser I had when I ordered, for the correct phaser limiter and core. So I should be good. Going to get it tuned end of this month.

Yes, that is something everyone using a VVT cam should be aware of. There are two different cam phasers and cam cores. I have a 2009 Escalade L92 motor but it has the earlier phaser. So be careful when ordering the parts. Check the part number on the phaser in your motor and buy the appropriate cam for it and cam phaser limiter kit.

Yea I knew that there where different phasers depending on year and thats what they said when I ordered the cam so thats why I thought they asked for the phaser p/n, so they could get me the correct limiter but didnt know about the cores at the time and they didnt mention anything but since they had already done testing of the vvt 1-3 cams in a ly6 test engine at their facility at that time I figured they knew what they were doing. Dropping the truck off to be tuned on the 23rd so we'll see if something isnt right.

This has been posted before in other threads but worth repeating. The earlier cam core is number 156 and goes with Comp Cams phase limiter 5456. I don't have the number of the earlier GM phaser in front of me but I believe it ends in 944. The latest cam has a core number of 189. I don't know the Comp Cams phase limiter number or the later GM phaser number. Just beware that you order the right parts or you will be off something like 13 degrees on your camshaft timing.

Thanks man thats great info. Well see what kind of power im putting down in a few weeks hopefully they are as good as people have been telling me and can get a fair amount of more power out of my truck. Top end seems pretty strong but i could always use more cruising power down low and better mpg. Need to fogure out the launch. Maybe my drag radials arent right for my setup?

Thanks man thats great info. Well see what kind of power im putting down in a few weeks hopefully they are as good as people have been telling me and can get a fair amount of more power out of my truck. Top end seems pretty strong but i could always use more cruising power down low and better mpg. Need to fogure out the launch. Maybe my drag radials arent right for my setup?

Looking forward to your results. ;)

Were you able to improve upon the tune that I sent you? Just wondering if you were able to get it any smoother.

I have a 4.8 with the newer style phaser. The cam I installed was from a forum member with lttle knowledge of what core is was. Is there a easy way of figuring it out?

"Is there a easy way of figuring it out?"

With my VVT-3 camshaft from TSP the cam core number was on the outside of the box. I expected it to be etched on the camshaft but it was not. Maybe contact the people who ground your camshaft.

That's the problem I don't know who did the grind. It has the barcode on it like a factory gm cam and some other hand etchings. Definately not a stock came and has been in the engine 3 or so months. Just doesn't have any pull on the bottom end. 219/228 550/550 114 in a 4.8. I have another post today about it and saw someone mention on this thread about decreeing to make sure its correct core.

Were you able to improve upon the tune that I sent you? Just wondering if you were able to get it any smoother. Hmmm maybe? Haha its been so long and ive tweaked the tune so many times since then that its hard to tell. My laptop has a power supply issue where it wont accept power anymore not aure of the power port is worn out from being my only computer for 8years or something. For now im stuck using the internet on my phone and looking for a replacement laptop. Once i get a working laptop ill email you my file for you to try.

"Is there a easy way of figuring it out?"

With my VVT-3 camshaft from TSP the cam core number was on the outside of the box. I expected it to be etched on the camshaft but it was not. Maybe contact the people who ground your camshaft.

just checked out my comp cams box from tsp since i still have my stock cam sitting in it and all the tags have been scratched off.

"just checked out my comp cams box from tsp since i still have my stock cam sitting in it and all the tags have been scratched off"

Mine was like that to. However on the side of the box towards one end the core number was still there. Mine was something like 189-000-1. So it will start with either a 189 for the later cam core or 156 for the earlier cam.

Looking at hicksport's dyno sheet below for his VVT-2 LY6, there is about a 60ft-lb (roughly 20%) rise in torque between 3,100 and about 3,700rpm. Below that the dyno isn't clear. That may be the jump you're feeling. If you look further down, I also posted TSP's L99 results. It seems to have about a 40ft-lb rise in the same area, roughly a 12% increase in that case. The jump is probably a bit less in the L99 case due to the increased compression ratio. In both cases, the flattest range of the torque curve seems to be from around 3,700rpm up to around 6,000rpm. I think if you want more power down low you'll want a smaller cam or a cam with more lobe separation, but you are probably going to give up some power at the top end. For example, take a look at futureuser's results with a vengence stage2 nonVVT cam here (http://i1136.photobucket.com/albums/n482/Daniel_Howell/dynosheet.jpg). Looking between 5,000-6,000rpm, his torque curve starts to drop off whereas the VVT-2 stays steady, but on the bottom end he has more torque over a pretty broad range from around 2,800 to maybe 3,500 or so. His cam is similar in lift & duration to the VVT2, but has a wider LSA and possibly a different lobe profile. Keep in mind he's going through an auto tranny.

hicksport LY6 VVT-2 w/ manual tranny
http://i1184.photobucket.com/albums/z327/chicks7477/Dynoshot.jpg

TSP L99 w/ auto tranny
https://www.texas-speed.com/images/media/vvt2chassis.jpg

I look forward to seeing what you get after a tune. You may want to have the tuner focus on that range from say 2,500-3,500 to see if they can make improvements with cam timing. Unfortunately I'm not sure if closing the intake sooner is going to save you from the valve overlap at those RPMs.

I picked up about 10 hp and didn't give up any torque in my latest tune. We also pulled a little timing so I can add a little you know what.

futureuser, I digitized your dyno curve and hicksports using Excel. You definitely have a leg up with your combo. I wonder where the difference is coming from since the cams are so similar in @050, lift, etc. Maybe the wider LSA? Or all in the tune? It looks like the VVT-2 uses LSL lobes. I wonder if Vengence is using LSKs or some other lobe.

or a DIFFERENT dyno!!! LOL

I'll have to look into the type of lobes. I thought wider lobe separation had a tendency for smoother idle, more top end power and less bottom end torque? I'll look into the type of lobes. With the latest tune I have slightly more horsepower and about the same torque. The run with the converter locked has a spike, so the 433 torque is not accurate. But it's amazing what a good converter can do. I traded 16 hp for 67 lb/ft of torque and can still lock up the converter in the top end if I want to get back the lost hp.

I had two different tuners tune my car. 1 used hp tuners and 1 used efi live. The results were about the same with the later picking up 9hp. But my lighter weight converter and the engine breaking in a little more may have had something to do with it. I got a full complimentary re-tune because hp tuners locked us out of the van program with no solution in sight.

http://i1136.photobucket.com/albums/n482/Daniel_Howell/dyno2.jpg

or a DIFFERENT dyno!!! LOL

Yes dynos can vary. I have run 11.72@116 mph at 3700lb race weight in my brick, uncorrected this summer without nitrous and 3.42 gear. I think my numbers are conservative.

futureuser, I think wider lobe separation favors lower RPM output due to reduced overlap. That last dyno you posted has a wild early torque peak and a completely different shape from your first dyno run. Where is all that early torque coming from? Here's the original for reference.

http://i1136.photobucket.com/albums/n482/Daniel_Howell/dynosheet.jpg

Maybe I'm wrong, but my understanding has been that wider LSAs are better for high rpm power and tighter LSAs make better throttle response and more torque. I'm pretty sure the wider LSA's favor forced induction and Nitrous as well. I was surprised to get a nearly 8/10 drop in ET with just a 90 shot of nitrous for my 11.01@ 123 run.

Here is a reference article:

http://www.popularhotrodding.com/enginemasters/articles/hardcore/0606em_camshaft_specs/viewall.html

The latest graph I posted is much harder to read than the first. There are two runs on the graph. One has the converter locked (blue lines) and one has it unlocked (red lines). The locked run has a spike when the throttle is nailed (at a higher rpm) and shows the spike early in the run. This spike has to be disregarded and the rest of the run matches the original torque curve. The run with the converter unlocked looks nothing like the other. The converter multiplies the torque at lower rpm and I get less peak power.

In the original run, the converter is stock and locked. The new graph shows the new fti converter unlocked and locked, and the massive torque at low rpm which explains my huge ET drop when I swapped converters. I don't have the low rpm documentation of this new locked run, like the original, but it it clear I make a few more pounds of torque.

Also, I forgot to mention I did a little porting of my stock LY6 throttle body, which may account for a little of my new found power. I have run on the old tune with the ported throttle body but have yet to run on the new tune. I expect the booger to be quicker.

Ill be running on a mustang dyno on monday and continue being tuned via hptuners ( they're actually going to use my hptuners cable and module to save from having to buy credits and therefore saving me money). My truck weighs 3850 with me in it.

'Sorry about the major hijacking, and good luck with getting some great results!

No problems at all. I also thought wider lsa gave a smoother idle obviously but also more down low tq.

not to hijack the thread..but while youre talking about a LY6 vvt cam swap and the phaser I have a question...I sent my build sheet to Pat G for a custom VVT cam for my ly6 out of a 2007.5 2500hd. When I was talking to Comp they said I HAVE to know which phaser I have and something about the bolts or how many there are on the cam. Does anyone know what phaser/bolt style this year ly6 motor has( its a non afm/dod/flexfuel motor)?

Why did they change em? Can I run the oem or is a MUST change item? Im trying to get all this together along with the cam(something in vvt form of a tr224) and springs to match along with pushrods too and then have it tuned by Tampa tuning(Phil'sC5vette)... I wanna do it right the first time. Thanks and great thread btw!!

Here's another article on LSA:

http://www.compcams.com/technical/FAQ/LSAproperties.asp

not to hijack the thread..but while youre talking about a LY6 vvt cam swap and the phaser I have a question...I sent my build sheet to Pat G for a custom VVT cam for my ly6 out of a 2007.5 2500hd. When I was talking to Comp they said I HAVE to know which phaser I have and something about the bolts or how many there are on the cam. Does anyone know what phaser/bolt style this year ly6 motor has( its a non afm/dod/flexfuel motor)?

Unfortunately you can't really go by the year. For example my '07 LY6 had the "newer" version of the phaser whereas the tech bulletins would tell you otherwise. You have to go by the part number on the phaser. The phaser will determine which cam core and limiter to use.

Phaser # 12585994 uses Comp limiter kit #5456, 156 core
Phaser # 12606358 uses Comp limiter kit #5460, 189 core

To get to your phaser part number, you can remove the water pump and VVT magnet. If you look at the second picture below you can see my phaser part number etched near the top left ending in 358.

http://cjnn.xtremefabricator.com/images/LY6swap/ly6swap247.JPG

http://cjnn.xtremefabricator.com/images/LY6swap/ly6swap248.JPG

That is correct. You will have to look to see which phaser you have. My L92 came out of a 2009 Escalade but has the earlier phaser 12585994.

Damn..so i gotta tear apart my motor to get the correct cam phaser? that sucks. Comp said I can find the correct one by VIN. What do you think. My plan was to stockpile all the parts then do the install when im ready. Its my DD, so tearing it down and waiting is not good news..

Looks like you just have to remove the waterpump and then the phaser piston cover to check.

Trucks at the tuners. They are backed up from a problem vehicle so wont be tuning mine for another hour or two. I work 3rd shift so I wont be able to watch plus its 45mins away so ll let you know what she puts down whenever I find out. My buddy said hell try to make it there and get a vid.

doesnt sound too bad..I wonder why comp is emailing me saying you can get the correct part # via the VIN..that sounds almost too easy to be true.

A video of the new cam would be great..

[QUOTE=quicksr20;16548715]doesnt sound too bad..I wonder why comp is emailing me saying you can get the correct part # via the VIN..that sounds almost too easy to be true. "

I don't see how that is posible.

Buddy of mine is at the tuners since he lives close to it and is good friends with the owners. Says it looks like they wont get to my truck today either. But they will take a vid when they do.

Calling it quits its not getting tuned until i can figure out the vss issue.

What happened? What did they say?

Sorry didnt notice i havent been updating u guys. Tossed it on the dyno last night and before they mess with the vvt they wanted to run a crank relearn to make sure the ecu knows whats going on. I never could run crank relearn on my hpt it starts then just aborts. They try there modis scanner and it says the truck is in 1st going 158mph. My hpt scanner shows 158 mph at all times but the speedo reads correctly so i figure it was just an hpt issue. Guess not. So they researched all day but before messing with it they asked if i wanted them to keep working on it not knoing what the price might end up being or if i wanted to pick it up and look into it myself. I chose the later. They looked at my ve and maf table and said they look almost spot on just a little tweaking but with the ecu thinking its always going 158 then its pointless tuning for low end since its not actually going into the low end of tables and without the crank relearn the ecu might not have the camm positioning 100% correct.

Thanks for the great info. I noticed the thread in the conversion section regarding this: http://ls1tech.com/forums/conversions-hybrids/1569286-whos-solved-158-mph-vss-input-e38-ecu-t56-swaps.html Looks like HPT may have a solution for it here: http://www.hptuners.com/forum/showthread.php?t=36796

Thanks man. I found that last night through some other members going to try it out on my e67 and see of i can get it to work. Sent the guys at the tuners that thread this morning which brought up if i wanted them to muddle through it and see what happens or save the bill and work on it myself. That may fix the 158 issue but will it fix the other problem with the crank relearn that its saying its in 1st gear?

Finally got my truck and laptop back. Heres a pic my buddy sent me. Its the farthest the truck ever got. Atleast they could have made one pull to see where its at.


http://img.photobucket.com/albums/v493/tiresmokinV8/Noma/0726121917.jpg