Originally Posted by LIL SS

One thing to look at for drag racing is the work over time. Example being:

I made a pull to 105mph in my truck that I logged. Here is the time spent in each RPM range:

4k and bellow: 2.3 seconds (20%)
4k to 5,500: 5.1 seconds (44%)
5,500 to 7k: 4.2 seconds (36%)
--------------------------
Total time 11.6

Now this was not a full 1/4 but I was still only at 5,200rpm in third when I let out. By my estimation, I'd probably be at about 110mph at 5,500 which I'm guessing is about where this truck would trap the way it sits.

So if you look at work over time, based on my final gearing, I would want a cam that really works that 4k to 5,500 rpm range but still holds strong to 7k.

Originally Posted by bmax

Thanks Predator

Have not changed heads yet but was planning on 64.5 cc and a .040 gasket.

Thanks

Brad

Edit to add.
I was looking at xe lobes before, not xe-r.
Is it better to run a higher lift as you said or can I run the smaller lift and be easier on valve springs?

eta2. when I check dcr with your suggestion @ 2 deg adv. I get 8.78, when its straight up I get 8.64.
with .040 quench can I run dcr that high?

thanks

Originally Posted by GMmexican

Predator im going to be cam only with the tr 230/224 with bolt ons........and most of the guys in my car club are going to be cam only/bolt ons as well but most of them are running a tsp ms4..........how will my 230/224 match up against them?, i figure ill have more low end since the ms4 is a dog down low.

Originally Posted by oz304

keep thinking along them lines and the engine is gonna inhale more than its capacity.a cam like that should work best with maximum velocity cylinder heads+just enough efficient intake valve size + exhaust primary diameter stepping out as go along the way.its the key to maintaining critical air speed momemtum.
do excessive exhaust porting + or shove big valves on the lsi head for a na car then you got only two choices,throw the heads in the rubbish or run single pattern +victor junior(if they makem + lots and lotsa revs.
ironically i remmember years back on a 5 litre after explaining i didn't give a rats about dynos but rather wanted to maximise ve + torque with enough revs to do the job,the cam grinder came up with a compromised flat tappet solid profile for some very basic heads with very minimal mods from what i remmember

258@50 in 107 /550lift
253@50 in 108 /525lift
+ dialed it in approx 102lc
i never raced that car in the quarter mile officially
but for a 2950lb with 3.08 + 4 speed muncie + very conservative non wheelspin launch it got me to 60mph around 4.5 to 4.7 secs.
and on the test road refferenced track was doing over 190kph terminals+dynoed within 25 bhp compared to one of the best 5.0 oz group a touring car 87 spec carby engine (albeit mine on 95 ron + his on 98 ron + with the bigger valve ducks guts b casting non efi cylinder heads).
conversely in a mag test report in 91 a leading 620bhp+ 5 litre efi holden supercar accelerated to 60 mph in 5.1 secs ( though i dont know if therec was excessive loss of traction,but one would imagine with sticky dunlop slicks it may not have been that excessive anyway)
another 8 litre 454 motec equipped efi quoted @ 700+bhp in a similar car to mine managed the 60 in 5.2 seconds
them blokes didn't run reverse splits incidentaly.
air speed is everything.
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Originally Posted by PREDATOR-Z

One thing I learned a long time ago comming from "old school", when it comes to heads on LS motors, it is a hole new ball game. Quench area, chamber shape, position of plug, shape of runners are all much more advanced than SBC/SBF older tech.
Heck a stock LS6 head flows as much or more than a fully ported SBC one.

Even though I think I'm pretty well versed in cam tech for LS, I keep being surprized by results that most poeple usually dismiss because it doesn't follow mainstream. To discover new horizons, one has to be able to think outside the box.