Dragaholic

iTrader: (180)

I'm not ready to mess with the bottom end yet. If the motor comes out, its going to be fully built. I'm running the MTI C2 cam (224/.581/112) and I really want to upgrade cams. T-Rex is what everyone recommended me for my set up, however, the cam's powerband is from 3500-6700 rpms. Then those using this cam are getting best results shift between 6800 and 7000 rpms. Well, my car is a 2000 model and I dont think my motor is up for 6900 rpm shift points. Those that I know that are doing this with a completely stock bottom end have 01-02 cars. Anyhow, what I was wanting to know is if the T-Rex is worth doing if I'll be shifting the car before the cam's powerband ends? I wont be able to spin my motor that high to be in the powderband the whole time. Will I still see gains over my current cam? Will I still have a chance of breaking into the 10s? Thanks.

Boostaholic

iTrader: (4)

Think higher than 6500, like 7000 or 7200.

Dragaholic

iTrader: (180)

I know those using this cam are getting best results shifting between 6800 and 7000 rpms, but my question is if its worth swapping over to with 6500-6600 rpm shift points. My bottom end cant handle rpms any higher than that or at least I dont wanna try.

luv2spd

iTrader: (1)

I would go with something smaller like the fm13 or something like that. Maybe even the MS3. The MS3 also likes higher rpms, but it doesn't need to be spun quite as high as the t-rex.

Joe "Preachers Sheets" DIESO

iTrader: (4)

6,800 rpm would be fine. My light is set for 6,800 and my limiter is at 6,900.

lilone

I don't know if you would want to or not. On my auto I broke the 400rwhp mark at 5600rpms and peaked around 6500 so that would be cutting it pretty damn close...

Fireball

iTrader: (21)

I'm ETing best with my shift light at 7000 rpm

If I pull the trigger at 6600 I'd probably slow down 1-2 tenths easy

if you are worried about revving...get a smaller cam

CamaroCain

iTrader: (1)

I would have to agree with this person. If your car really isn't setup for a cam like the T-rex the MS3 (Magic Stick) cam with a Yank PT4400 would be the best setup IMO

Dragaholic

iTrader: (180)

luv2spd: I really dont wanna go with something smaller because sooner or later I'll build the bottom end. But do you know what the powerband is for the MS3?

Joe "Preachers Sheets" DIESO: I'm sure it'll be ok to shift the car a little earlier, but what I was wanting to know is if I will still see significant gains over my current cam (224/.581/112) and if I still have a chance at breaking into the 10s cam only.

lilone: Are you running the T-Rex cam? Reason I ask is because I was wanting to know why you were posting your power at 5600 rpms, your peak,etc.

Fireball: If the T-Rex's powerband is between 3500 and 6700 rpms, how come you are shifting 300 rpms above its peak? Does it not drop quickly after it peaks? Do you really think there will be 1 to 2 tenths difference from me shifting from 6500-6600 to 6900-7000?

CamaroCain: The MS3's specs are up there with the T-Rex's, why would you recommend this cam over the T-Rex for a car that cant shift into the higher rpms. (6900-7000) I checked TSP's site, but didnt see any specs on the cam besides the cams specs, do you happen to know wha the MS3 peaks out to or the powerband?

Fireball

iTrader: (21)

I'm basing my assessment on track testing. 6800 rpm shifts were almost .1 slower than 7000 rpm shifts..

gomer

iTrader: (13)

Damn! Did you ever redyno after playing with the cam timing? I'd like to see the before and after graphs on top of each other

CamaroCain

iTrader: (1)

high 230's/low 240's is not right up there with the T-Rex if I remember reading the specs on the T-Rex. Are you still running the 200R4 trans? Why can't you get the rpm's to 7k?? What does it matter if you say you are going to build up the bottom end eventually anyways??

I am running the MS1 cam in my car, but the specs are close to the MS3.
MS1 = 238/242 .605/.610 112+4
Here is my graph www.texas-speed.com/caindyno.jpg

Lynda

Scalpel

iTrader: (4)

He shifts higher due to the fall in RPMs experienced with the MN6 b/w gear changes. The higher you shift the higher you fall into the RPM range. With cams, such as this, that are designed to max high RPM power you want to stay as HIGH as possible in the RPM range so that you're maximizing the useable power. If you shift before 6700 you'll fall WAY down in the power band and be much slower b/c you have to spend more time getting back into the higher RPM range where you're making the most power. This is why when Fireball shifts sooner he goes slower, consistently. He falls into a lower RPM range that has lower available power, hence he must use MORE time to climb back into the most efficient power range.

So, in answer to your post title, No.

The T-Rex is NOT worth it if you're not going ot use it for what it's designed for. You will probably go SLOWER than your current setup b/c you'd not be utilizing the cam in the way it was designed to be used. At least with your current cam at the same shift points you're utilizing MORE power b/c that cam makes its max power lower in the RPM range so you wouldn't be falling so steeply out the power potential as you would with the T-Rex.

Scalpel

iTrader: (4)

I see it as being nearly impossible, to short shift a T-Rex and make it into the 10s. Hitting tens, with essentially a cam being the only mod to the internals of the engine requires one HELLATIOUSLY setup car, from the ground up. Suspension, weight, drivetrain, driver skill, etc,.

I wouldn't say it's totally impossible, but I can say that you'll spend a lot of time being VERY frustrated trying to hit 10s short shifting it.

Dragaholic

iTrader: (180)

CamaroCain: I was merely stating that they were close.

T-Rex: 242/248 .608/.612 110
MS3: 237/242 .603/.609 113

Im still running the 200-4R. Its not that I cant get the rpms to 7k, its that my bottom end will not handle it. The reason I mentioned that Im going to build the bottom end eventually is because I dont wanna "downgrade" cams now and then have to upgrade again when I build the bottom end.

CANNIBAL: Very well put! You are very knowledged in this department. I'm always amazed at what you have to say, and Im not being sarcastic. I understand completely what you are saying, but would it apply to me one who is using an automatic? I have a PT4400 and it has really high shift extension or at least thats what Ive read. So the converter keeps the rpms high and doesnt let them fall as low. Plus I have 4.10s. Would you consider my car to have a hellatious setup or a set up that will get me into the 10s with only an internal mod of a cam?

Fast Toys ram air kit
K&N air filter
Texas Speed & Performance air lid
ZO6 85mm MAF
SLP high flow bellow
Bauer Racing ported & polished throttle body
LS6 intake manifold
NGK TR-55s
Holley 9mm wires
Kooks 1 3/4" stainless steel long tube headers
Custom 3" true duals w/Dynomax bullets dumped
ASP underdrive crank pulley
Meziere electric water pump
MTI C2 cam (224/.581/112)
Manley valvetrain kit
AMW oil catch can
Billingsley ABS delete block
Century 200-4R w/all options
Yank PT4400
TCI flexplate
Hal shocks in a 4 corners w/R series in front
Spohn-LCAs, PHB, TA, SFCs, & 25mm rear sway bar all in chromoly
BMR-K-member, upper & lower a-arms, & relocation brackets
Airlift airbag
Prothane motor mounts
Energy Suspension tranmission mount
Denny's nitrous ready driveshaft
Strange 12 bolt w/4.10
Bogarts-15x10/ET Drags 15x4/165R
Wolfe chromoly 6 point weld-in roll bar
Weight reduction

Scalpel

iTrader: (4)

You're gonna drop far less in the RPM range with that tranny/gearing setup so you will not suffer nearly as much b/w shifts as one would with an MN6 setup.

In your situation, you'll still not be maximizing your potential (because you're still not utilizing the entire powerband) but you'll surely be in a much better position than a person with the exact same setup yet having an MN6.

As far as predicting what you'd actually run, or if your gains would be significant. I can't really say. I don't know your expectations of gains that you would consider significant. As far as hitting 10s, I don't have enough experience and knowledgebase with your type of setup to give an educated guess.

I'm hoping others that are more familiar with the rest of your platform can chime in.

Dragaholic

iTrader: (180)

Well all the T-Rex owner that I see around here are 6 speed users and they shift higher past their peak to stay in the higher portion of the powerband where the most power is made. However, what if Im running a really efficient tranny and converter with really good shift extenstion to keep you in the higher rpms, and a fairly low gear? I know the drop between gear shift isnt going to be as bad as it would with a 6 speed. Ok...here is where Im getting at, lets say cam A is the T-Rex cam and B is the other cam. Now we know that the T-Rex cam has a powerband of 3500-6700 rpms and we'll say cam B has a power band of 3200-6400 rpms. Cam B wont have to be shifted as high because it has a lower powerband. Well when drag racing, my car shift at 6500-6600 rpms and the converter doesnt let the rpms fall any lower than 5500 rpms. So what we need to look at is what cam makes the most power between 5500 rpms and 6600 rpms correct? Well what if the T-Rex cam was short shifted a little, but still made more power between 5500 rpms and 6600 rpms than cam B. Then would it matter if it was short shifted or not? I know that my gains would be a little better at slightly higher rpms, but if the T-Rex is making more power in a given rpm range than another cam, wouldnt the T-Rex be the cam to choose? In this case Im using the T-Rex for cam A, but cam A could of been any cam.

So in a nutshell, what Im asking is, even though the T-Rex is being shifted before its powerband ends, if its making more power than another cam in a given range of rpms, wouldnt the T-Rex be the cam to go with? I know that it would benefit me even more if I were to shift the car higher because I would be even higher into the powerband, but lets just say Im shifting the car early.

Scalpel

iTrader: (4)

Bingo.

Based on your scenario, yes.

Dragaholic

iTrader: (180)

Wow...I feel like Im getting the hang of this. So how would I find out what cam makes the most power between 5500 rpms and 6600 rpms? Would I need to find a cam with a powerband that ends at 6600 rpms or sooner? So if I do ever find the perfect cam for my set up, do I have less of a chance of hitting 10s cam only than those shifting at higher rpms even though Im maximizing my set up getting the full potential out of a particular cam? In other words, say 2 set ups were maximized, however car A's shift points are a big higher than car B's, even though both set ups are maximized, does car A have a better chance at 10s because his shift points are a big higher?

Scalpel

iTrader: (4)

I would honestly have one custom done, by say, Allan Futral.

That way you'll be getting a cam that will be much more able to do EXACTLY what you want instead of having to fumble through all the different tuner/vendor websites to find an "off the shelf" grind. That's the only way you'll get your ideal cam.