Good cam size for stock 318 bottom on boost

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bigtommy said:
Buckshot, is that rpm range for that cam good? 3000 seems alittle high to start power. Or is that why I get a 3500 stall or higher?
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I think you need a cam with about 220 degrees duration at .050"-lift and a 115-degree lobe separation. Forget about all this lift; you can move more air in there with a higher boost setting on your waste-gate,. And, yes, an alcohol/water injection system will be money well-spent.

That is really good advice on the 2.76 rear gears and doing this with torque rather than high-rpm horsepower, will save money on engine-longevity, and valve train pieces. Redline it at 5,500 and get a wideband O2 sensor, whatever you do. That will be your best friend! Good luck!!!:cheers:
 
bigtommy said:
Okay the only problem the bigger 112 or 114 cam I can find is .461 lift. I'd like a .528 or something or that too big oh a cam for turbo. Because I know too big of a cam I'll be slower then stock lol. And what's a good rpm range camshaft and stall so I can launch is with boost off the line.
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Did you even look at the cams I speced for you? The crower flat tappet has 0.521 int./0.528 exh. 112 ls. The Crane is 0.480 int./0.500 exh. 114ls (and with a 1:6 ratio rocker would yield .505/.528

lift has very little impact on streetable charactoristics of a camshaft. Duration/lobe separation and overlap do.


bigtommy said:
Buckshot, is that rpm range for that cam good? 3000 seems alittle high to start power. Or is that why I get a 3500 stall or higher?
Click to expand...


That is an average range and it doesn't mean it won't make power below or above that range. It doesn't even mean you engine will make power in that range.

No disrespect, but you really don't seem to have enough experience or knowledge to undertake a turbo build.
 
roccodart440 said:
Did you even look at the cams I speced for you? The crower flat tappet has 0.521 int./0.528 exh. 112 ls. The Crane is 0.480 int./0.500 exh. 114ls (and with a 1:6 ratio rocker would yield .505/.528

lift has very little impact on streetable charactoristics of a camshaft. Duration/lobe separation and overlap do.





That is an average range and it doesn't mean it won't make power below or above that range. It doesn't even mean you engine will make power in that range.

No disrespect, but you really don't seem to have enough experience or knowledge to undertake a turbo build.
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yeah I don't know anything about turbo builds that's why I make this post.
 
Bill Dedman said:
I think you need a cam with about 220 degrees duration at .050"-lift and a 115-degree lobe separation. Forget about all this lift; you can move more air in there with a higher boost setting on your waste-gate,. And, yes, an alcohol/water injection system will be money well-spent.

That is really good advice on the 2.76 rear gears and doing this with torque rather than high-rpm horsepower, will save money on engine-longevity, and valve train pieces. Redline it at 5,500 and get a wideband O2 sensor, whatever you do. That will be your best friend! Good luck!!!:cheers:
Click to expand...

This guy has been doing forced induction, a long time. And a damn good recommendation. With a turbo,you don't need overlap(long durations/narrow lobe centers).All that does,is blow the boost out the tailpipe. RustyRatRod's cam choice: Sweetness,on a budget. Bill Dedman's ,jailed the correct specs.You gotta learn,somewhere....
 
Abodybomber said:
This guy has been doing forced induction, a long time. And a damn good recommendation. With a turbo,you don't need overlap(long durations/narrow lobe centers).All that does,is blow the boost out the tailpipe. RustyRatRod's cam choice: Sweetness,on a budget. Bill Dedman's ,jailed the correct specs.You gotta learn,somewhere....
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yeah i know i dont want overlap and the cams everyone is showing me has a higher intake so it will overlap.
 
Mad Dart said:
What fuel? Intercooler? Meth injection?
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I run it on LPG (Propane) blow through. Propane is quite popular in australia and its quite easy to setup and cheaper to setup compared to a Petrol (gas) setup.

I run an ebay 600x300x100mm intercooler, 3" in/out

I have also just fitted water injection not to cool down intake temp but to reduce cylinder chamber temp. LPG (propane) burns hotter in the chamber then Petrol as it has no cooling effect, so im going to use the water injection to cool down the chamber. Basically just to help the stock cast pistons survive.

It would run better with 3.25 or 3.0 gears in the rear for sure, its what was in there to start with and so far its going fine. The only issue i can see with running 3.0 gears is loading the engine up too much at low/er rpm which may cause stock parts to expire sooner.

BigTommy click the link i posted earlier, you're not going to find anything better for what you're after off the shelf. The only other cam i would consider off the shelf would be this.

http://www.summitracing.com/int/parts/sum-1798/overview/make/chrysler

Keep things simple dont over complicate it. Standard rocker arms are light and strong, so are stock pushrods. Run a good single spring with a damper and you'll be fine to 5500rpm, theres no need to turn it any higher with the amount of power you're chasing you'll just end up braking stuff. It is only standard stuff at the end of the day
 
2times said:
BigTommy click the link i posted earlier, you're not going to find anything better for what you're after off the shelf. The only other cam i would consider off the shelf would be this.

http://www.summitracing.com/int/parts/sum-1798/overview/make/chrysler

Keep things simple dont over complicate it. Standard rocker arms are light and strong, so are stock pushrods. Run a good single spring with a damper and you'll be fine to 5500rpm, theres no need to turn it any higher with the amount of power you're chasing you'll just end up braking stuff. It is only standard stuff at the end of the day
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imma go with this cam. thanks. i like it. i found on summit the cam and lifters for 150. now how do i go about getting springs for this cam. im runing 360 j heads if that has to do with anything. http://www.summitracing.com/parts/sum-k50062/kitcombocontents/make/chrysler?prefilter=1
 
bigtommy said:
imma go with this cam. thanks. i like it. i found on summit the cam and lifters for 150. now how do i go about getting springs for this cam. im runing 360 j heads if that has to do with anything. http://www.summitracing.com/parts/sum-k50062/kitcombocontents/make/chrysler?prefilter=1
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It depends on a few things.
- Valve heights?
- Are you going to modify the heads to suit dual springs?
- How much boost do you plan on running?

I run standard 360 heads with no modifications so i was limited to spring choice. I went through valve spring catalouges at my local parts store and picked ones that would fit. I ended up using a Ford Clevend single spring with a Damper.

130lb @ 1.68" Seat pressure
260lb @ 1.18" On nose pressure.

These are pretty weak springs for a boosted setup but seem to be working fine in my setup up to 20psi but if i rev it more than 5500rpm it falls over which i think is my valves bouncing.

If your heads are apart I'd machine for dual springs and run dual springs with pressures around

130-150lb Seat pressure
300-320lb On nose pressure

Remember springs will loose approx 20lb pressure after a few hours run time.
 
Glad I saw this thread! Lots of good info in here! I have a 318 stock bottom end with a .70 a/r T3 turbo, needing a cam. I talked to comp cams and bought custom grind hyd roller with .490 lift w/ 1.6 rockers, 115 lsa, and 218 dur. intake/exhaust at .050. $340 and I can still use the stock distributor gear. Pretty good deal I'd say!
 
The stock 340 cam is an excellent choice for forced induction.
 
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