Working with a stock rebuilt 5.9 magnum, ported magnum heads, m1 single plane, 750dp will be doing hangar18 mods,msd programmable 6, behive springs, hardened push rods.

Currently motor is n/a, cam specs are as follows 304/306 adv dur, 242/[email protected], .556/.560, IVO 15 IVC 47 EVO58 EVC10, 110 lsa.

1st question is how do you think that cam would perform on an s475 with the 93/1.32 turbine?

2nd, I am setting the car up with an hx52 right now as i already have one, and they are close in physical size to the s475 which i will be upgrading to. Is my cam too big for the holset? If so what are some cam specs that you would recommend for this setup?

Also this will be with no intercooler, running pump 93, and a direct port water meth kit as my intake is already drilled and tapped for it.

If you need any more info let me know

Thanks

 

Hopefully Duner sees this thread for you. He has built some good power with a turbo 5.9.

 

Anybody ?

 

Way too much overlap. With turbocharging, start with a cam that has no overlap at 0.050", or negative overlap at 0.050"
Also, most cams are ground with 4 or 5 degrees of advance, and most good timing sets offer the option of 4 degrees of delay. This is a good thing for turbocharging, especially for a dual-pattern cam with a little more exhaust duration.

 

I went from a 312/.590/106 LSA to a 284/.528/112 LSA camshaft. Honestly, the first cam performed dramatically better IMHO at my lower boost levels. Engine felt w-a-y down on power, reacted slower, and spool time and RPM was near identical to the proper turbo grind; but I'm sure there was some reversion in the process as well with the first camshaft. I would run your current N/A camshaft, if it doesn't perform well, get a custom ground from Comp/Bullet/Lunati, etc. Ballpark figure, 230-235* @ .050/.580-.600/112-114 LSA.

 

What was the engine and turbo setup on that comparison?

 

Not a SBM so there is no comparison, just my experience. I would try it out, worse comes to worst, swap in a custom grind with the S475 turbo upgrade.

 

Fair enough, Thats what i was hoping to be able to do. Any benefit to advancing or retarding the cam with an adjustable timing set?

 

Like I said, that would all depend on the combination and how it performed. If you care about the sound of your engine and don't want it to sound bone stock, you're going to want a camshaft with overlap. That's not important to everyone, but I can't swallow my pride in that regard owning a 'muscle car'. I just don't believe these engines perform better with wider LSA's, low duration, and lower compression ratios (out of boost/low boost scenario) and I've noted that after swapping 5-camshafts over four years. It may be different for a SBM, especially if you're shooting for 12-20 psi, but anything under 10psi and I wouldn't lose sleep over it.

 

Seriously, you wouldn't lose anything with a no-overlap cam, if you keep the same eo and ic points. All the duration that adds overlap is worse than wasted, it's counterproductive. You want window area, get it with rocker ratio.

 

Are you saying the second cam you have listed is a turbo grind? who did it if so?

 

No turbo grind from a builder, contacted three different camshaft manufacturers with no response. Went with about close to a turbo grind specific (off-the-shelf) for a BBM as possible; 112 LSA/240* @ .050/.500 lift after lash. I'm running a really basic, low-boost build (sub-10#) that won't destroy parts. If I wanted more power, it certainly wouldn't be with a wedge'. Engine made poor power with this cam with relatively low overlap, I could care less if it made a few more HP @ 7-8 PSI due to reversion, you're not in boost during 95% of everyday street driving. In a hotrod, you want it to sound great (which requires massive duration and overlap in a big-block, much less required for a small-block to achieve the same effect) and unless I went solid/hyd roller, you're not going to find an off-the-shelf camshaft with relatively low-duration and massive amounts of lift (like most modern-turbo camshafts for LSx/SBF/Hemi). 99.99% of people have no idea what a Road Runner is, let alone that a low-overlap camshaft normally results in higher boost levels/increased efficiency at lower-rpm.

I think all of our info is a bit worthless, as it's trial-and-error for the most part (every combination is drastically different). I'm not a hardcore racer so losing some performance past 10+PSI doesn't really matter to me. I built 6.5-7psi with this cam (about all I can do on pump fuel and 10:1), 4-speed, and 4.10 gears at around 4k with a rolling start at highway speeds.. Blown through centerforce clutches and was on the verge of destroying my 833. No doubt I can make the same boost with the automatic and higher gears, actually, I did but the converter resulted in me switching the camshafts after the auto install. New 112 lsa cam made boost at nearly an identical RPM, no obvious improvement, other than sounding like a grandma's car and looking pro-stock (just my 2c), just not my style.. Opinions may vary, and I'm sure they do.