cam

iTrader: (9)

The TR224 is a tried and true proven cam that tons of people love including me. Made great power yet still maintained reasonably civil daily driver street manners. I'm building a VVT 6.2L now and wanting a cam and even though the options as of now are very limited I'd really appreciate hearing from anyone who has experience and try and find the all around best street cam for the VVT set up.

I have a t56 so dont care so much about idle and I want to make as much power as possible but want the car to cruise decently at 2000 RPM or so. I have to face heavy traffic here and bucking and surging down low can be extremely annoying. So from my research the cams available as of now are;

MAST:
224/238 115 unspec'd lift
230/244 112 unspec'd lift ( Mast is tight lipped about these )

Comp:
210/224 114
214/228 114
218/233 114
222/236 114+3 *all comp VVT cams are .560 .570 lift or very very close to that


So at this point I'm thinking of either the Comp 222/236 or either of the two MAST cams. I'll be running 1 3/4" longtubes through a 2.5" y into a mandrel bent 3" single exhaust and an LS3 intake with ported stock throttle body.

So let me here your input it please.

Patrick G

iTrader: (14)

First off, people put way too much duration on the exhaust for L92 cams. It is not necessary. The L92 exhaust port flows more than the old LS1 port and slightly better than the LS2 port.

A 6.2L is 30 cubic inches larger than a 5.7L LS1 and would therefore require 5-6 degrees more duration to behave the same. That means the exhaust duration needs to be 230. No more. The massive intake valve needs 6 degrees less duration to behave the same as a 2.00" valve in an LS1. Therefore, the ideal intake lobe would be 6 degrees less than 230.

Your 6.2L equivalent cam to the TR224/224 would be a 224/230. You can quote me on it.

cam

iTrader: (9)

Sounds sensible to me. Only drag is comp doesn't make vvt custom grinds according the techy I spoke with at least. There isn't an existing vvt 224/230 so it looks like mast cam 1 or comps biggest are around the closest to those specs but I have to wonder...

Is it not wise to go for a bigger cam considering the benefits of vvt? I'd have to think that with good tuning the bottom end could be dialed in and really the tr224 was a great street cam because it didn't give up too much of it's low end grunt that bigger cams lost. Maybe I should get the big mast piece and go? Seems pretty large though and I was planning on stock heads so maybe I'm just dreaming

Patrick G

iTrader: (14)

There are VVT custom grinds and you can even get them with over .600" lift. You just have to ask the right people.

cam

iTrader: (9)

yahaaaa! Perhaps if I read members sigs once in a while I might just find such people

cam

iTrader: (9)

Work your magic Patrick. Lets make some POWER!!!

sinisterC4

Its on my list for Patrick to do one for me.

cam

iTrader: (9)

My cam is en route as I type so I'll update how it works out. I ended up with an EPS custom grind that is right around where Patrick mentioned above. I do hope to put down big numbers even though its a "relatively" small cam. Initially when i started this thread my thoughts were the TR224 was a great cam because of its balance between low end drivability/torque and high RPM power. Overall a great all around dd cam that many will agree.

What I wanted the VVT for was to go with a cam that would otherwise be "uncivilized" yet make TONS of power up top and my thoughts were by utilizing the benefits of VVT I could tune back civility down low. Well As great as that sounds I have uncovered a few hurdles that really has me doubting how big the benefits of the VVT system actually is.

The biggest issue is piston to valve clearance. Considering this if we want to use the VVT for big cams and move the cam advance/retard around then the variable cam positions gobble up more of the "room" we have to play with in terms of ptv clearance. This in turn prevents you from installing a bigger cam in the first place so big cam/VVT engines are simply not truly possible and this is why most of the cams mentioned above are around the .560 lift range. Its not that these cams wont make great power or that the VVT doesnt work out but it seems to me when looking at the cams that work out extremely well for the LS3 engines we cant have our cake and eat it too as there simply isnt enough ptv room to do it all.

Ok so probably wondering what that means? Basically it means that if you build an LS3 or any 6.2L with L92 heads no VVT then you can make as much or more power as you could with VVT. So really all the VVT system does is add more variables to tuning, cam selection, ptv clearance, and more parts that could fail for very little benefit. Its clear that VVT is a better way to fly so to speak when comparing equal components but because you can get into different and bigger cams without it AND those builds dont seem to be giving up much bottom end as a result I just dont think its overall worth the effort to swap in a VVT set up.

If your car or truck has the VVT I would just drop in a VVT cam and go. In my case Im swapping this engine into an older f-body with a t56 so the hurdles involved for getting one of these in and running right are very large and as I see it the benefits of VVT are not really worth it.

If I could back up the clock I would have either kept my LS1 harness and PCM and converted the L92 over or ran and e38 harness and base tune from an LS3 vette/camaro and ditched the VVT...

Which may end up happening anyways if I cant get the power out of this thing that I want. Theres still a long way to go for my build as of now. I'll be a few weeks before its up and running but I will update my findings after Im done.

jmilz28

iTrader: (13)

I think you made the right decision going with PatG's cam. The 6.2s don't need donkey dicks to make brutal power and I'll bet the VVT is going to do a fantastic big block impression in the mid range. There is a 230/236 that has gotten nice results over on CF also. I don't have VVT in my LS3 but my cam is not too far off MAST's big cam spec. Drivability is decent, she's happy at idle and above 1500 cruising. City mileage is iffy (14-15 pure) but I've knocked down 25MPG highway cruising and she put down 465/444 SAE on LMR's dyno through a regular ole SLP lid and dual dual...so I am a believer in rectangular port heads. My guess is you're going to LOVE that setup you're building, just make sure you pay someone to spend the time tuning it on the dyno and the street. I wish I'd gotten Patrick to spec me a cam...

cam

iTrader: (9)

Indeed this is the key to success for certain.

I'm working out what/how this will play out now and having my fair share of stress about tuning this particular animal as I am running VVT, e38 ECM from an Escalade, and a t56. Combining all those elements adds up to a nasty bees nest of confusion that I have to organize and control to make sweet honey. I am quite curious to how well this cam will work and I've been noticing that the EPS lobes seem to work exceptionally well on a lot of set ups lately so for that aspect Im drooling.

But considering my swap factors Im more concerned as of now than excitied unfortunately. I just hope I can get all the pieces in my build working like a good band playing the same tune so to speak

buddyholly

Cam, great post. Since we keep frequenting the same threads we are in much the same boat. My LY6 has me nervous about just getting it running. My plan is like yours but I am doing it in slower steps. My current LY6 will be installed in my '76 GMC truck and I am going to run the stock cam until I get it running and sorted out. I then may install a bigger cam and see what the motor can do. My ultimate goal is installing a L92 or L9H in my '71 Chevelle with a t56 with a nice cam but I want to make sure I know how it will react. The Chevelle is my daily driver and cannot be down for months on end.
I have yet to hear from anyone who has tunned the VVT. My thoughts on the VVT is that the stock profile is probably a pretty good curve to start with but I am a ways from thinking exactly what VVT tuning will do with a aftermarket cam. The little I have seen in the Comp Cam that was dynoed fails to mention any changes in the VVT timing so I guess they left that part alone and just installed the cam. http://www.gmhightechperformance.com...rting_cam.html
Keep up the post and maybe someone will have this all figured out before we get to be the guinea pigs...

cam

iTrader: (9)

Well I'll sure know soon enough as I hope to have it running within this month.

Likely correct. My thinking is this. Dialing in the cam position for max power is as crucial as dialing in your timing curve for max results. I think the stock cam timing curve will probably fare "better" than using the same cam in a static position in terms of power output but... GM only starting using these VVT engines when the epa requirements became higher and higher. As a result these VVT cam timing curves are likely a lot more focused on fuel economy then they are for max power just like the stock ign timing curve would be. I agree completely that there is NADA posted on any forum that I have seen about how to tune these cam timing curves effectively but as I see it its a simple game of trial and error. A truly systematic approach to making adjustments and testing results is the only way anyone will ever get anything more from one of these systems and thats exactly what i intend to do. I've tuned a ton of stuff before and I dont know if any of you have two stroke experience but you want to talk about BLACK ART? Hahaha I raced sleds for years and tuned tons of sleds and was beating the biggest names in the game back in my day and I have the broken bones and written off machines to prove it hahaha. Anyways the trick to tuning is simple. Make ONE CHANGE AT A TIME and test it whether that be dyno or track or with your a/f gauges etc. One needs to keep a good clean notebook thats organized and systematic and one by one you check off your trial and error and victories and in the end you'll end up with some cherry pie machinery.

I've tried sourcing out some info on this and spoken with over the phone with some vendors on how to approach this. One shop owner actually yelled at me when I started asking the right questions and he then yelled at me to ditch the VVT or I'd never get it started LOL umm ya ok. He had confessed to me however that he had spent over a month testing and tuning to come up with a cam/tune combo that he offers now for L99 Camaros. He posted his graphs on some other boards and Im not overly impressed with the results. Maybe its because its through an auto, maybe his dyno is stingy, maybe he didnt do a very good job. Lots of maybes but regardless he was VERY tight lipped about what the cam specs were and even angered as mentioned above about his tuning "secrets"

In the past I always respect others work and efforts and never spill the beans on any info when I've been asked to keep quiet about what they were up to and how they were doing it. I have no issue with that honor is important in my book. But when i keep getting the door slammed in my face and left high and dry out in the cold then I have no choice but to turn to the boards and try and sort this crap out.

When i figure out what works for me I'll post up about it and hope to know soon whether or not its worth the aggravation to run VVT for swaps.

jmilz28

iTrader: (13)

I think you'll be rewarded for your efforts. GM Powertrain seems super smart over the last 15 years or so. They've focused on mechanical efficiency, leveraged by great head design. They've kept (ahead) of pace simply by focusing on fundamentals, no electronic/programming gimmicks like DoD or VVT until recently. Once those two things are added, LS/GM motors leapfrog again. I love the VVT because it makes a small motor act like a big one when you want it/all the time with no penalty. I think investing a few dollars with MAST and/or PatG would give you great returns and allow you to really shortcut how long it would take to get great results versus doing it all by yourself. Besides, PatG is **** enough that he might be one of the few exceptions to the addage "If you want something done right, better do it yourself." The trick here is that the VVT doesn't add a layer or factor of complication, but an exponent, an order of magnitude.

Are you going to get it running with the stock cam first and then switch? Sorry if I missed that...
Regardless, keep us posted on your progress.

cam

iTrader: (9)

I couldnt agree more and I have the end of summer as my goal for dialing this thing into perfection so I think thats a realistic time frame. I doubt it will take me that long but I'm prepared to work that long and hard on it to dial it in.

Im dropping in the custom cam from the get go.

As for MAST I did speak with them a couple of times and they dont support stock PCM's at all they only offer their own stand alone which isnt really what i want. If I go stand alone Im stepping up to something way better than MAST's stuff but I dont think thats going to be nec as of now. Outside of trying to sell me their stuff they didnt seem any too interested at all in offering up any tips.

As for Pat G? Hes already been the most helpful guy on the boards thus far and I'd gladly let him tune it but its a long drive from Toronto to Texas

FWIW I even paint my own cars. I do it all. Nothing on my cars has been built by anyone but me. I build the diffs, trans, engines, body paint etc. Im as passionate a gear head as you'll ever find. I should also mention i build and help a ton of local friends out with stuff all the time. I dont ask nor want any money but if you know me then I do have a soft spot for a 24 of Labbatt Blue especially if you want to drink some with me and shoot the ****

cam

iTrader: (9)

Cam arrived today! I hope to drop it in next week but I'll be a while before I get to tuning as I have a lot of work to do before this build is complete.

twin74s

iTrader: (10)

Any info on this?

cam

iTrader: (9)

Sadly the cam is still sitting in the box and the engine on the stand. To say this has been a busy year is a massive understatement. I do have just about everything needed to bang this thing together but because its a swap car and Im upgrading to an e38 PCM etc etc there is a LOT more work than just a cam and tune. That said I still hope to have it running before end of August. I will be dynoing and reporting all ( good or bad ) but I have high hopes and expectations for this thing.

I love those 6.2L VVT's sooooo much i just ordered a new 2011 pick up 2x4 with a 6.2L hehehe. Outta catch a few napping with that one especially after a cam, headers and a tune

Probably go with a smaller cam than this one on the truck though it doesnt need to be a max power effort just a nice 400 whp type thing. Which may even be possible with bolt ons and a tune. Time will tell.

Higgs Boson

iTrader: (3)

well?

cam

iTrader: (9)

Slow progress but progress nonetheless. The cam is installed and the accessory drive is together. I rebuilt the t56 which was corked there was a LOT of messed up parts in there so I ordered a stage 2 kit initially then upon tear down had to order a bunch more stuff which up here in Canada adds a month or two practically by the time its shipped out etc etc.

I reworked the cars rear suspension and did a gear swap as well. Re-did all the brakes and the fuel system is done now too.

So Im getting there4 slowly I have been working on it and as mentioned above theres a LOT more to this build than a simple cam swap.

As of now I am working on the wiring harness and beautification of the engine and accessories. Once those two things are completed I will stab the engine and trans back in the car and get to tuning it. My goal as of Jan 1 was to have it running by March but life keeps getting in the way so now Im aiming to having it up and running sometime in April.

I will update when I have more to add. All in all there was around 140 hrs that I had to find to do what I have done thus far but that is time hard to come by for me these days. I have fallen victim to taking on more than I can handle. Thankfully I dont give up

BTW the new truck is awesome

MotoFreak

niiiice