[61-63]

Gary I just clicked around on the net and according to what I read on several sites it says they grind 4 degrees of advance in to provide more low end torque. If they ground the cam straight up and you installed it straight up you would have slightly less low end end torque but have more power at the upper end of your RPM range, at least that is what I think I read. Now for someone like you in a '63 Tempest with a 421 cubic inch engine, do you need that little bit of low end torque? Or will I with my 462 cubic inch engine in a '63 Catalina? I don't know. And could we feel the difference in the seat of our pants were we to drive two identical cars one after the other, one with a cam advanced 4 degrees and the other with the cam ground straight up? I don't know that either. Hopefully some experts will weigh in here.

[61-63]

Gary you were right a tighter LSA increases compression

http://www.compcams.com/Technical/FAQ/LSAproperties.asp

[grparen]

John, yes I have been surfing the internet today and most say there is an increase in compression and potential detonation with a tighter lsa (though there are a few that say it is the other way around). Since my compression is between 10:1 and 10.75:1 and I have experienced detonation issues previously (even with 93 octane), I am leaning now towards the 110 lsa vs. the 108 lsa. Anybody else want to chime in?

[tom s]

Just try a pumping comp test.We cant get pump gas over 91.I have found that pumping over 170-180 leads to detonation with iron heads.CR does not always account for it.Cam timing does.The deal about bigger cams bleeding off compression does not to me hold water.We put in bigger cams to make more HP,where does it come from?Cyc pressure!Untill we can find out how to go everywhere and do everything at idle we will have a issue with detonation at higher RPMs where it can go easily undetected till the bearings are knocked out.Tom

[Johnny406]

I'm running that Lunati 10705 cam on my 463 with a pair of 660's. It runs really well for my bracket car with right at 10:1 on 87cc E-heads.

[grparen]

Johnny406, is your Lunati 0705 cam ground on a 110 LSA and how choppy is your idle? I like a real thumping cam.

[Johnny406]

Yes it's on a 110 and quite thumpy even though I am using V-Max lifters. Have you considered calling Lunati and having them grind you a Bootlegger cam? They will gladly do it.

[Ragtop Man]

A narrow LSA will be a partial solution for a high static CR. But... what do you want to use the car for? Drags? Street? Idling around the parking lot at a show?

Pushing the curve up the scale will make it less street friendly, stick or no.

Might be a good idea to track down one of the online calculators and see what it gives you for DCR, which is really what we are talking about here. That is the best gage to estimate the fuel tolerance.

[grparen]

Johnny406, on your two 660 carbs do you know what the size of your primary and secondary jets and metering rods are? Just curious as to what has worked best for you for your setup.

[Johnny406]

Originally Posted by grparen

Johnny406, on your two 660 carbs do you know what the size of your primary and secondary jets and metering rods are? Just curious as to what has worked best for you for your setup.

The 660's are Holley's so no metering rods. I can look at my log tomorrow for jet sizes but I live and race in the clouds (6000 ft elevation) so I have to run leaner here do to the lack of oxygen.

[Johnny406]

Here's a snotty cam that should run rather well for you. Ken Brewer had this custom ground for me a few years ago before I intended to use nitrous on my combo. It's new in the box.

[grparen]

Johnny406, Wow! That's a big cam. Remember, my engine is 428 (421 bored 30 over), about 10:1 compression, 3.42 rear end and dual carbs (currently two 400s and maybe going to two 625s). I want to drive this on the street to car shows and cruises. Isn't that way too much cam for me?

[Johnny406]

I actually had it ground for a iron headed 10:1 (ported though) 455 but with a race focus. Kinda funny, a few weeks ago I asked here about running a pair of 400 AFB's myself (I have a really nice pair) on my 406 with a small Comp 270S cam. It's in the street performance thread. I'll probably throw on the 500 Edelbrock AVS carbs for initial break in and tuning and then I may try my 625 Street Demon's that I had on the 455 on the Offy intake.

[tom s]

You want "lumpy"to get that you need a bigger cam and narrow LC.You have to decide if you want something to drive with a moderate lump or something you will hate to drive but like the sound.Im going to tell you with your rear gear a cam in the 236-246 on a 112 will get you some good sound and you will like the way it drives.245-252 with that 3.42 IMO sucks,been there done that in a couple diff cars and couple diff engine combos.Tom

[61-63]

Gary what Tom is saying is that with your rear end you need to put a McKeller #10 in the car, which has pretty much the numbers he posted 236/247 @ .050 with a 114lsa.
Of course that is his opinion you may like the way your car drives with a bigger cam than that.

I tell you what I will give you the new Lunati 07703 we talked about. I've got a couple I bought from people for no good reason. You can run it and if you don't like it we can pull it out and I will take it back. This way you and I both can find out what it sounds and drives like in your car.

[brut4s]

So what did you use?

[grparen]

Lunatic Voodoo Dual Pattern Duration 276/284 and 504/527 lift. Good power and great sound.