i have a 350 bored 40 over with summit 17350-40 flat top pistons stock rods and crank im using stock vortec heads and i am wondering what cam i should get for this setup with out doing head work the engine had a lunati 06108 cam in it which im guessing is to small since i shouldbe running like 10.4 1 cr or so i was told by someone on this site if im wrong please corect me but any help or advice would be helpfull thank you

 

Is your car a computer contolled system (ECM)? I ask because im selling a GM Perfoance roller cam that is non computer controlled. Its got about the same lift that a LT1 cam does. The cam Im selling onley applies to a carburated system.

 

OP: You didn't give us enough info. You're correct that you're around 10.4:1. What's your axle ratio? what's your converter stall if you're running an automatic? And if it's an automatic, is it a TH350 or 700R-4? How will you be using the car? Do you have headers and a good exhaust? Is your block pre-87 or '87-up?
Chevy86: You're asking too much for that RamJet 350 cam, and it won't work in pre-'87 blocks. It works fine for TBI engines, and I've already posted before telling everyone where they can get that cam for under $65. That thread was about 3-4 months ago. Lastly, that cam you're pushing won't work with 10.4:1 compression, it barely tolerates 9.4:1 with Vortec heads and premium gas. If you want to sell it, lower the price and put it in the section for selling parts, not pushing it on people who can't use it. Use good manners.

 

Allita the fun,m the cam only has like 3 hours of engine tuning until I called Summet (the seller) and they told me it was a mistake that the sales rep sold me that came for my TPI system. Plus my 86 has a 350. You may think 86 never came out with 350s but your wrong, only a hand full came out and theres no sheets to verify that. the only way to verify is by reading the vin code. 1986 IROC's came out with B2L and not the L98. Ive done my research. So good info, the cam will work for TBI. Thanks for the advise. Keep in mind that I was reffered to this cam by the Summit Racing sale rep. I had all the questions thrown at him and he told me that it is a steal for that price if i wanted horse power gains. Plus I already posted in the classifieds. I posted here to this gentleman as an offer. Whats the problem with that? I didnt try to get shysty with him at all. I let him know the bare bone specs. Let it be bro. Let him answer for himself. Dont pounce on someone who is trying to help another out. you dont know if this cam may be sutible for his engine. Besides, did you read my profile? Ive dropped in a 350 block. If your interested on the years of the block hear you go - 14093638 1987-95 350 2/4 Roller or flat tappet cam one-piece rear seal.

 

To everyone else, I just told him the same things as I'm sure a moderator would. Also, I am qualified to say whether his cam would work for this person's engine. This person has since exchanged PMs with me. I do know the specs of the cam this guy is trying to sell. And for choosing cams, I've been doing it professionally, as part of my job, for over 9 years, with not one complaint in the last 8. I even had a chance to man the phones for one of the major cam companies. I'm under legal contract to not specify which company. I had to turn that chance down, but they really wanted me.

 

"I'm under legal contract to not specify which company."

Ok then, why wont the ramjet work for my TPI. Oh and please, explain. You seem you have knowledge that I lack. Enlighten me.

 

If you can answer why the cam isnt computer controlled, Ill then Ill stand down. But if not, I think that you being a cam expert for 8 or 9 years, makes you feel a little too proud of yourself. Please dont flatter yourself. You can say all that you want just to make yourself feel superiour over others. All it takes is a little arrogance and pow, an argument ensues. But I aint mad. Peace.

 

first off do you have an answer for my question other than trying to see me your used cam that you have know idea if it works in my car let alone for my compression so if not then **** off second try reading what was said about the cam very slowly and you might see that he stated that it
WILL work for a tbi but not for a pre 87 motor which mine is so you argueing with someone that knows what there talking about and trying to sell me a roller cam for a non roller motor wow and so you can read it again heres what he wrote sound it out if you have to

Chevy86: You're asking too much for that RamJet 350 cam, and it won't work in pre-'87 blocks. It works fine for TBI engines, and I've already posted before telling everyone where they can get that cam for under $65. That thread was about 3-4 months ago. Lastly, that cam you're pushing won't work with 10.4:1 compression, it barely tolerates 9.4:1 with Vortec heads and premium gas. If you want to sell it, lower the price and put it in the section for selling parts, not pushing it on people who can't use it. Use good manners.

 

Chevy86 IROC-Z i did clarify just i did it in a pm with atilla the fun like he also mention i guess you couldnt read that either though and this is my post you tried to sell me a bull **** cam that wouldnt work even with out the specs you should know that cam wont work with 10.4 1 compression so learn your **** before comming at me selling crap and for your info its a pre 87 block 350 bored 40 over vortec heads headers dual exuast dumped before the rear end 700r4 650 cfm holley with vaccum sec a crank from a 69 350 bout to change gears to 3.73:1 gears and a 2400 stall converter

 

easy guys. first, the RamJet 350 cam is okay for some TPI applications, it sometimes wants a lot of tuning, but tuning gets so costly that it's usually cheaper to just pick a cam that's well proven to be a happy match to TPI. And really, it's a great cam for TPI if you can get it tuned. I don't do tuning, I pay for tuning. But I have a good working relationship with a local chassis dyno shop. I get to hear back how much re-tuning any of my customer's cars required. TBI is pretty tolerant of this cam, despite being speed-density. It's usually easy to get good results with the stock GM PROM chips. Just adjusting the TPS, the initial timing, and the fuel pressure tends to get it spot-on. This cam, even with an RPM AirGap, is all done around 5100 rpm, and stock TPI intakes are all done around 4800, so they're pretty closely matched. Now, The ease of getting it to work for TBI makes me feel safe telling people it's okay for TBI. Is it the best choice? If you're still running 2.73:1 rear gears, and stock compression, then yes. For TPI, you can keep better low-end torque than a TBI can, when using a cam with a later intake closing, as GM did. The RamJet cam, combined with TPI, tends to result in detonation. That'll destroy engines. So it's best to just choose another cam.

 

Atilla the Fun, I appologize for my actions and comments. Thanks for explaining the specs. I can see that schottout doesnt know the facts just like me. Atleast I know how to act like a gentlemen and not blow up like he did. Its obvious that he has to go to anger managment.

 

If you have TPI, and want truly amazing midrange torque, go ahead and use that cam, but you'll need a tune that pulls alot of spark advance out in the middle rpm range, but not off idle or up high. Stock timing is tolerable on premium fuel, up to 2000 rpm, and above 4000 rpm, IF you use that seafoam stuff to de-carbonize your combustion chambers.

 

Success!!! I complained to the BBB about Summit. Summit told me to return the cam even if it has been installed. I called back and got another rep and they told me too late. They basically told me to buy another cam. One of the veteran supervisors called me and told me that they recieved a complaint from the BBB and they appologized. The gentleman told me that he reviewed the recording and found that I wasnt honored what I was told. So he told me to pull the RamJet cam and send it back for a full refund. I asked about tuning the PROM and he told me its cheaper to buy a 4th Gen LT1 cam for around $50-100. He said that it would cost more to get tuned by a dyno shop.

 

that's all true, but the LTx cams won't give as much midrange torque, they work at higher rpm, where the stock TPI doesn't.

 

I never thought of that (TPI high restriction). Here are 3 pictures of the cam that Im getting so that maby you can Identify what it is , brand wise? Im not sure if it is even an LT1 cam. If you know what it is, Ill appreciate it if you can let me know.

 

to be sure of what it is, you're going to need a degree wheel and a dial indicator.

 

Ok. So other than the lift or size of the lobe, what should and how do I check the specs using a degree wheel? Can a machinist figure this out for me without installing the cam?

 

not unless they have a thing called a "cam doctor", but with just the degree wheel and the dial indicator, you can find the intake duration at .050" lobe lift, the exhaust duration at .050" lobe lift, and the lobe separation angle, as well as maximum intake lobe lift and maximum exhaust lobe lift.
All this can be done in less than an hour, it's not difficult at all. I can walk you through it if you want.

 

Yeah, that would be great. When you got time of course. I dont want you to use up your personal time.

 

I'll start tomorrow.

 

 

I'll assume you have a magnetic base, and dial indicator with a 1" range. Secure the degree wheel to the crank, put a bolt in a hole in the blo0ck, wrap a length of wire, like an old coat hanger around that, and set it up to be your pointer. Set the dial ind. up on the deck, with the base and tip both on the deck, and the dial reading 0.500", midway through the travel. Now move it so the tip is on the frontmost driver-side piston. We're going to start by finding true top dead center. Watch the dial while turning the crank. You'll probably see the dial spin up to about 0.475", then start back down. So, bring the piston up to where the dial reads 0.450", and note the reading on the degree wheel, it doesn't matter what it is, or where your wire is pointing, just don't touch the wire for now. Keep turning the crank until the dial again reads 0.450", and note the reading on the wheel. Halfway between the 2 is true TDC. So turn the crank until you have true TDC, then adjust the wire and the degree wheel to get a reading of zero.
That's the end of step one. I'll make every effort to detail step 2 this afternoon.

 

Now, nou need to set up the dial indicator to be touching the first lobe. This is the exhaust lobe for the drivers front cylinder. Turn the crank until you're sure you're on the base circle of that lobe, and set the dial to zero. Now you can slowly turn the crank until the dial reads 0.050" of lobe lift, and read the number on the degree wheel. It should be somewhere between 55 and 35 degrees before bottom dead center. Record this number, and resume turning the crank until the dial reads around .250", at which point, turn the crank very slowly and watch the dial for the highest measurement. For an LT1 cam, it might be around .307", for the ZZ4 cam it should be 0.340". Anyway, whatever it is, record that, and continue turning the crank until the dial again reads 0.050", and read the wheel. It'll probably be something like 15 to 5 degrees before top dead center. record that, then move the indicator to the next lifter hole back and repeat. This time, the lobe should give an opening between 10 degrees before top dead center, and 20 degrees after top dead center. move on to peak lobe lift, then intake closing, which should be between 20 to 45 degrees after bottom dead center. Again, record what you find. In my next post, I'll detail how to make sense of it.

 

Okay, now you have numbers you might see on a cam card, but you want familiar numbers instead. This is easy, but you may want a calculator. I prefer to do it in my head, but doing it with pen and paper lets you check your work. First, multiply the peak lobe lifts by 1.5 to find the valve lift. Even if you will be running 1.6:1 rockers, start with 1.5, then you can do it again with 1.6 if you want. Next, add 180 to both the intake closing number, and to the exhaust opening number. Then, unless the intake opened before top dead center, subtract the intake opening number, and likewise for the exhaust. Here's an example, using the ZZ4 cam:
EO 45.5 degrees before bottom, EC 4.5 degrees before top, IO 5 degrees after top, IC 33 degrees after bottom. Intake, 33 plus 180 is 213, minus 5, is 208 degrees intake duration. Exhaust, 45.5 plus 180, is 225.5, minus 4.5, is 221. so you now know you have 208/221 duration. To find the lobe separation angle, will be in my next post.

 

inding the lobe separation angle; Start with the intake duration, divide it by 2. For the ZZ4, that gives 104. Now, add the 5 degrees, since it was after top dead center. That gives 109 degrees. That's your intake centerline, with a good timing chain. Now, do the same thing with the exhaust. 221/2-110.5, plus the 4.5, gives 115. 109 plus 115, divided by 2, gives the lobe separation angle of 112 degrees. And since the intake centerline is 109 degrees, that means this cam has 3 degrees of advance ground in.
I'll check back next week in case anyone has any questions.