Bigwebb

does this place additional strain on the valve train and require more frequent refreshes?


Daniel

KW Baraka

Not sure what you mean by "additional strain".

I will only say that the additional lift will most likely result in a need for a spring upgrade.

With my .667" lift, I can't use the commonly used .650" and .660" lift springs. I have to use .700" springs.

But my .700" with .667" lift will last as long and be as reliable as .650" springs with .625" lift as long as the springs are properly spec'ed for the rest of the valve train.

Obviously.....all bets are off if 'junk' parts make up any component (spring kit/rockers/lifters/pushrods) of the valve train.

KW

Bigwebb

thats what I mean, a higher pressure spring exerts more force. The rocker is creating more leverage as well with the increased ratio. All things being equal, wouldn't you want less leverage, less force, less spring pressure on a series of moving parts?


Daniel

KW Baraka

The additional pressure necessary for controlling more lift is a minimal concern......in most cases. The key is to get the 'right' parts. You get items that are spec'ed for your setup and any issues are more imagined than real.

For instance.....you can get .700" lift springs that are spec'ed for hydraulic roller valve trains.....and you can get .700" lift springs that are more suitable for solid roller valve trains. Put the wrong springs in either setup, and you end up with too much or too little pressure.......and an engine that will grenade on you.

Since Tony Mamo is doing your heads, I recommend that you get with him directly regarding fleshing out the valve train......to include your cam if you haven't made that purchase already.

KW

veneno

curious what brand cam you have? I am looking for a cam to go with my yella terra 1.85 rockers and some places I reached out to don't recommend using the 1.85 rockers they want me to step down to 1.7's reason being better valve train geometry. I have hardened push rods, .660" beehive springs so what's the problem if I have total lift around .620" with the 1.85 rockers? I would go with cam motion core the lobes should be easier on the valve train. Tick and texas speed dont recommend the 1.85's are they using aggressive cam lobes?

veneno

you need rockers so just go with the 1.7's
yella terra are good and lighter then the oem rockers. No need for
higher ratio rockers unless you have a low lift cam

KW Baraka

I have the Lingenfelter GT1-1 cam, Comp Cams Ultra-Pro-Magnum rockers, PAC-1206X valve springs and Comp Hi-Tech rods.

Valve train geometry should not be an issue when you properly measure for pushrod length and properly install your parts.

If you're looking to go with .XXX" cam lift, it's best to get there with the mildest lobes multiplied by the highest rocker ratio available......IMHO.

KW

Bigwebb

decided to go with 1.8 ratio rockers

jstewart

I have not been here for a while so missed your questions. The cam has 20,860 miles on it. The spring kit was installed with the cam & had 19,400 miles and was still in spec when I changed the heads. Of course the new AFE heads had a new PAC spring kit. The custom grind Spinmonster 230/234 cam has been used by quite a few forum members here with good results.

Bigwebb

Thanks for the replies. What RPM are you spinning to with that setup?


Daniel

jstewart

6,800 RPM, You can find a dyno sheet I posted on the forum under my name titled new engine project nearly done and ready for tuning dated 6/21/17. Very broad nearly flat torque curve with strong top end HP. Really good street build that delivers and is drivable and reliable using the stock LS3 displacement and bottom end. The only modification to the bottom end was to fly cut .040 deep intake valve reliefs for the intakes in the stock pistons. The heads were also milled for 64cc chambers & .040 head gaskets were used to get 12.4/1 compression. No problems on 93 pump gas. I sold this car last week to a friend to buy a 2016 ZO6 and the 08 car is still running strong.

cv67

Let Tony tell you what to buy, how it will work/last the best.

Can someone please tell me what guide material has to do with rocker type?

Saying a xxx lsa means xx is plain wrong. It doesnt most times. Again talk to Tony..theres some good info on the web...and a lot of stuff that will have you spending your money 3x over.

Bigwebb

how long can I expect valve guides and springs to hold up before the heads need to be refreshed on a setup like this? That is one of my primary concerns. I don't want to be redoing the heads once a year.

Bigwebb

anybody?

jstewart

Depends on how radical the cam is and cam lobe design. Very fast lift rates and higher lifts are harder on springs and guides. As I said before I had no spring or guide problems in 19,400 miles running the cam I used. When I pulled the heads to install the new AFE 255 heads the springs were still in spec and the guides and valve seals were good. I used stock rocker arms with upgraded trunyon assemblys.

Bigwebb

does the ramp rate thing only apply to ramp rate induced by the cam profile? Or additional ramp speed derived from altering the ratio of the rocker arms?

jstewart

Bigwebb we are now on the third page of this thread. As the OP you have solicited and gotten a lot of good advice and personal experience from members here. Some of the best advice was to use Tony Mamo as a guide through the thicket of conflicting information on the web. I thought I read somewhere here you sent the heads to Mamo for porting (my bad if I am wrong here). He will be the best judge of what cam profile, rocker ratio & springs to use with his porting and you're input on how you are going to use the build. No matter how many questions you ask here nobody here is going to have better insight into what works best than Tony Mamo.

Bigwebb

I appreciate your comments, but the reality of the situation is that the interests of someone in Tony's position and those of someone in mine, will never be fully aligned. This has nothing to do with Tony as a person or a professional, just stating facts. For instance, take a look at a dyno/strip number vs longevity relationship. One would assume that they are inversely related for the most part. Now I'm sure that every vendor on here genuinely wants to deliver both to the customer. But where I may be more inclined to sacrifice a little power for added longevity, it is in the vendor's best interest to "guide" the customer toward the better dyno number that will end up on these boards in a few weeks, as opposed to a better "40,000 mile review" that will likely never happen. Again, not saying what any particular vendor would "do", just pointing out what is in their best interest, and how those interests don't always align completely with the customer's.

So it is for that reason that I choose to take Tony's advice (you'll notice that I've done nearly everything he's suggested), while still trying to wade through the sea of information/misinformation on these here webs.



Daniel

HOXXOH

I've been following this thread for months and we're finally going to see some results sometime soon. The interesting part to me is the opinions generally seem to revolve around what results other people have done, but without knowing what goals those other people had. There are a lot of people who only mod their car cosmetically to suit their tastes and a lot more that tend to do stuff that in their opinion improves performance without knowing or caring about numerical results. So in the realm of documentation for power, we are limited to acceleration times/speeds and dyno numbers. Dyno numbers are simply a rough picture of a car's performance. There is little there that gives light to how well the street manners are or how quick the response is when carving canyons and only a small window into the expectations at the dragstrip. The only true test comes when driving the car in those situations that were in your intended goals and the only numerical results are those on a timeslip.

As an old fart who's transitioning from 76 Trombones to 77 Sunset Strip (song titles the young'uns haven't heard) next week, my goals changed several times in the 64 years since comic books and model airplanes were strewn in my bedroom. Although I've played with superchargers, turbos, and nitro in the past, I've always enjoyed the challenge of doing more with less. Cubic dollars was the standard for how fast fuel cars would run, but tipping the can a little more didn't require critical thinking. The most fun (automotive wise) I had, was running a low stock class and beating the Fords and Chevys with a Studebaker. Now my goals are to have a comfortable car to tour the USA in style, yet run 10's at the drags with only boltons. Yeah, I could do that easily with a cam/heads or power adders, but the challenge is still there to do more with less.

It's going to be interesting to see how quick Bigwebb's car runs at the track. Best of luck to him on his quest.

Bigwebb

Definitely agree on the lack of real world data out there. I will likely have a mustang dyno number and a dynojet number for comparison purposes. I will run it at the strip once or twice, but I plan to put R888R's on the car, and live with whatever traction they do/don't give me. I'm not all about drag times, so I'm not going to burn up my clutch or break the rear end trying to get on the fast list. My goal is to trap 130 mph. I may come up short there, but we will see. The main purpose of the car is to play on twisty roads, do a few hpde's a year, and still have something that I don't dread getting stuck in traffic with. I figure I'll own the car for another 40-50,000 miles, so I'm hoping that the setup will last that long as well. I think I've made informed decisions so far, so we will let the results speak for themselves.

As far as numbers go, I'm hoping for something in the realm of 515-525rwhp on a DJ.



Daniel