408trans_am

iTrader: (263)

Alright well i am putting together a 408 motor right now and really need help picking out a cam. I am looking for a cam that will be pretty much a track car with limited street time to shows and cruising ect. I believe patrick g was saying something about the vic jr and 4 barrel tb's possibly liking 106 or 108 lsa? Here are the specs so far,

LME 408ci iron
-2.2 cc wiseco pistons, 12.1 compression
compstar crank and rods
ported 317's that flow over .330 at .600 .340 at .650
ported vic jr.
holley 4 barrel tb
42lb injectors
ewp, drag race alt


5500 stall th400 w/ brake
ford 9" with 4.11's, spool, and 35 spline
28" et streets
3300 race weight

Any advise would be greatly appreciated. Looking to possibly get into the 9's on motor, then maybe a 200 shot on top of that.

Patrick G

iTrader: (14)

The Victor Jr intakes like an earlier intake valve opening and earlier intake valve close compared to running an EFI intake. A later exhaust opening/close point can usually be a plus for boosting mid-range torque. Both of these moves narrow LSA some. Most of the Victors seem to fall in the 109-111LSA range (on motor) depending on compression and cylinder heads. If you plan on running a big shot of nitrous, you'll need to open the exhaust valve much earlier while keeping the rest of the valve events very close to what worked best NA. This will widen the LSA. So as it stands, there's no tried and true LSA for the single planes. It all comes down to your mods and goals.

408trans_am

iTrader: (263)

patrick - thanks for posting up, very good info there and i totally understand. I am more concerned with how it runs on motor foremost. It will probably see a 150 to 200 shot on whatever the motor does. It will not run on nitrous all the time since it does see some street use and id rather take it to the track and run 10.0 on motor and 9.0 on spray rather than 10.5 on motor and 8.5 on spray. I guess i am saying that i am looking to get the most out of the motor NA. Your help is very much appreciated.

I was personally thinking that somewhere around 250/260 .640 .650 on a 110 would be a good cam for the combo. Anyone else have any suggestions?

408trans_am

iTrader: (263)

How does this cam look for my set up?

Comp Cams LSK Lobes 2132R/2133R 112+2 247/251 656/660

Patrick G

iTrader: (14)

Too late of an intake valve closing point to work well with that single plane intake. Maybe that cam on a 110LSA +4 advance.

408trans_am

iTrader: (263)

Thanks patrick, i might as well pay to have you spec me out a sweet cam. pm me on how to go about that.

XZ28X

Set up sound sweet man good luck, all i am wondering how you plan on taking that thing on the street lol

408trans_am

iTrader: (263)

LOL yea its always been a street car. Cam only i ran 10.7's with ms3 cam. I have always had the th400 and 9" even with my old sbc. That thing wasnt streetable, lsx motors have so much better driveability its great. Thanks

Slowhawk

iTrader: (12)

Watch out how much you advance the Cams.You would definitely think the intake timing should be earlier but my testing I've done has shown me otherwise.

408trans_am

iTrader: (263)

Thanks for the info, care to elborate a little more? I am very new to the whole single plane manifold and 4 barrel tb and really have no experience in larger displacement motors. I filled out a form for patrick g to help me out so ill see what he comes up with. Any little info is great since i am basically starting from scratch here. Thanks

408trans_am

iTrader: (263)

Well i got the custom specs back from patrick and it sounds like a good cam to me here is what it is...

Cam recommendation: (408 LS based short block, ported 317 heads, 12.1 SCR 8.48:1 DCR, Victor Jr. single plane ported intake with 4 bbl TB, Automatic with 5500 stall, 4.11 gears, no cats, 1 7/8” headers, 7200 rpm shift point, 7500 rpm rev limiter)
251/259 .624/.624” 110LSA +2 advance (with 1.7 ratio rockers)
Comp LSL/LSL lobes
13023R/13025R HR110LSA +2 advance (108 installed intake centerline)

I will be ordering it up soon.