Hoping to get a bit of feedback from those with similar setups - I think I've (finally) narrowed it down to a cam that'll be close to the following:
I already have the HSR intake & AFR 195 heads, but would like to hear how tough this would be to tune, as well as how streetable it might be, & if I might have problems getting thru the sniffer test...

EDIT: Also, roughly what shape will the torque curve have?

Thanks guys, I do appreciate it!

 

Are you planning to keep the MAF?

 

More to the story than just the cam. What intake system are you going to use? Also assume you are running headers with a good exhaust system. If you running the automatic you will want a higher stall converter.

The cam should have some lope to the idle but with a good tune should be very streetable. I would use 1.6 roller rocker to get the lift up some. With the AFR 195 heads you are leaving power on the table.

 

First off, sorry for the delay in responding, I had to work a 12-hr shift today...

OK, I did mention the HSR intake, but you're right, I didn't specify that I have a good set of coated headers. And yeah, a higher stall kinda comes with the territory - although I'm hoping to swap to the 6-speed by fall, & I might just do everything at once...

I don't think that I want to go with 1.6 rockers, if I need more lift, then I simply need to get a different cam.

Unlike most, my bottom line isn't going to be "*****-out power", I'm already going to be making all the power I'll need to run 150 on the salt. (The big challenge with THAT is balancing power w/ traction. I'm told that it's essentially like trying to run WFO on the freeway - immediately after a 4" snowstorm so being able to accelerate without spinning is key, they say that you can still be searching for traction at 130, & you've only got 1 mile from a standing start...) I also have to be able to pass emissions with this, so that's also part of why I'm not going w/ the biggest cam possible.

I do appreciate the confirmation that it should be a reasonably streetable cam though!

Finally Vader, yeah, I'll probably be keeping the MAF for at least the short term, I know that I may be approaching the edge of where the tables are, but if I've guessed right, then I should be able to get by for a year or so until I can learn the ins & outs of the megasquirt system that a buddy's using. I'm told that that uses the SD/MAP ECM info, so hopefully I can eventually get past the limitations of the MAF.

I really appreciate both replies, thanks guys.

 

Honestly, with that cam in a 350 i dont think you will need taht much of a stall. Long runners like to make torque and you've got them. You're duration is genoursly small for those heads. it will prolyl be an absolutely beautiful street driver, guranteed to let you play with the pedal and keep your traction... or not keep it. From what i have seen out of other similar motors with a cam close to that yours, torque peak is gonna be around 3.5-3.9k with a peak power around 5k (i estimated high and i may be a little above where it will actually be). Ill bet the cam claims valve float @ ~6k but i bet you can get another 700 smooth rpms past that. Dont hold this to heart. i have been wrong before. but i have been right many more times.

With your situation of wanting to run high speed's id prolyl go for more duration; spread the torque curve out and move it up higher, taking the HP curve with it. Getting off the line doenst seem like its gonna be your fastest zone.

Dont forget ot consider your gear ratios. Make sure your cam operates where your gears are gonna be. if you need to hit 150 then peak power shuold be around 135-140 in your highest gear. Its hard to judge stuff like that with out doing the math tho. Its better to use your power curve and integrate acc'd to gear ratios to get and esitmate of how much time youll spend in each gear and what distance youll cover. It gets pretty complex but i oculd prolly run the numebrs for you if you could get me a torque curve, gear ratios and tire size. I dont know how accurate it would be with changing atmospheric conditions at higher speeds but it would prolly be accurate for the first 100mph.

 

Elephantismo, that's gotta be one of the best answers I've gotten on this board while asking about running on the salt!

Unfortunately, I'm way too tired @ the moment to give a good reply to it, but wanted to say that you're dead-on w/ thinking that I want to move the torque peak up, etc...

I'll get into gears, etc. tomorrow, but wanted to take a moment to say thanks, & give you a big for your help!

 

OK, what would you recommend for duration, given all of the factors that I have to balance between? I'm definitely (strongly) in favor of flattening the torque curve, I suspect that the more "peaky" the power is, the tougher it'll be for me.

As far as gears go, I'm giving serious thought to just sticking with what I have now (3.27). I've thought of dropping to one of the factory rear-ends with the 3.08 gearset, but I don't want a "peg-leg" rear, & I do still want to be able to have decent acceleration.

If I still have the 700R4 when I do this, I'll keep it in 3rd gear, if I've been able to install the 6-speed, I'll go no higher than 4th - both should be 1:1, I don't want to go into OD 7 lose some "mechanical leverage" at the top end right where I'll need it most. (Need to get the gear ratios for both of those trannys for you, just don't have the time right now!)

I haven't had any luck getting power/torque curves from people, I might just break down & buy the Comp Cams engine modeling software so that I can play with it, & see what it suggests - but I doubt that it'll have an entry for "must pass emissions - Y/N?" or "Will you be running on the salt - Y/N?"

Thanks again for the great reply!

 

Ok. I'm gonna try to vitrual dyno your motor. This stuff is largely innacurrate for ACTUAL numbers, but it will give a decent idea of the hp and torque curve shapes, which will help in picking a cam. This program usually overestimates but we will see what its comes up with. you said you have AFR 195cc runners(shoot me a part number)? what size valves? We're trying to come up with a good estiamte of the flow values of your heads. Its likely somoene else has benched your setup. AFR benches everything and if they are untouched from AFR they either came with flow sheets or you can request them. you're running the HSR intake setup correct? You have 1.5 rockers? What kind of exhasut system do you have? What headers? Tube diameter? exhaust pattern(H,Y, true dual) and what diameter. Exact stroke and bore? Have the heads or block been decked? Flat top, dished or domed pistons(cc's?)?
Keep in mind, to make your motor perform like the program esitmates, its gonna have to have a good chip burned just for your setup. It may be neccesary to get some actual dyno time and pick up all the goodies for burning your own chip to get it where you want it. Theres some posts that go really indepth into how to do this.

I need your tire size. Its actually easier if you just measure the radius of a tire; from the ground to the center of the wheel is best. Our wonderful forums have the gear ratios for 700-r4's posted by years and they all seem to be the same <table border="1" cellpadding="1" cellspacing="3"> <tbody><tr align="center"><td>3.06</td> <td>1.63</td> <td>1.00</td> <td>.70</td></tr></tbody> </table>
I will need a good estimate of the weight of your car and the tire sizes once we have the engine curves. I'm writing up some Excel spreadsheets to compute stuff the easy way.

 

Update: I finished a gear calculator that is based out of microsoft word. I wanted to set something up so everyone could mess with it in a browser window without having to have excel or run an exe. I'm still thinkin but i have no idea so far. If anyone wants to help me out with this i'd appreciate it. msg me with an email address for the excel document.
Here is a Preview:

 

Sorry for the delay in responding, although I do have a good excuse...

I've placed my answers next to your questions, & highlighted them in bold.

Thanks again for being willing to lend a hand!!

 

NP
Glad to hear you made it out of your adventure semi-safely.
You shuold move to Texas. We have highways twice as long as the salt flats with half the people on them and no police. Plus we have huge droughts that last for months sometimes. And its always hot as hell here so you can ditch you block heater and forget about rust from salt in the winter. Plus we have rust free junkyards out in west texas.

Ok back to your setup. Here's what im lookin at doin. I'm gonna write a program that uses the torque at each different RPM to calculate the angualar acceleration of the wheel. This acceleration is related to the aceleration of the car, but not it exactly. There is parasitic energy lost from the transmission and the rearend. We will find the estimated coefficients for these values. The numbers should be availibe online. What we will do next is try to find an estimated static coefficient of friction between your tires and the salt you will be driving on. Next, we will try to approximate a drag coefficient for your vehicle. This may be where the most difficulty occurs and we may not be able to actaully find it without some hands on experimentation. We will use the estimated(and we will estimate for more los than probable) to do a force balance equation between the amount of force the car can exert forward and the amount of force exert back on it by the air, along with how much of that force will be exerted downward onto the car. We will acount for weight transfer by using the center of gravity of the car and the distance to each wheel to find the amount of weight on each wheel.
This shuold be pretty inclusive for determining the amount of power we need to output to get you car to 150mph within 1mile(this is our task correct?)
I'm gonna use what i know about your motor to come up with some dyno esitmates, but in the end it will be beneficial to actually dyno the motor to see if chagning any gear ratios would help out. These numbers should be availible by that point. This is heresay but a person on the board mentioned having had a dyno tuning and programming of a chip done for $350.

Any automotive physics whiz's out there that can see if i left out something obvious?

Also, are you in a big rush to get all this info together? It may take me a couple of days to write this code. Plus i have to figure out where my virtual dyno software ran off to.

 

Headin' off to work right now, but wanted to let you know that I've worked up the aero drag figures (measured in HP), a friend of mine & I did that using 2 different methods & came up within 3 HP of each other, so we're probably fairly close w/ that figure.

We've also taken a WAG on the coefficient of tire slip, but don't have the time to dig those numbers up right now. Basically, we figured out that if my engine's making 330 HP (seems reasonable, perhaps even a bit low), then I should be able to accelerate at the rate of 5.28 ft/second after taking the tire & aero drag into account.

Will that be enough? Who knows...

Thanks again, I'll see if I can dig that info up tonight.