Good Cam Choice?

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siuauto

siuauto

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I am building a stroker 340 with a set of trick flow heads. It's a Molner 3.79 stroke with their H beam rods and Wisco forged pistons. The compression ratio is going to be 10.6:1. OTB Trick Flow Heads with Hughes 1.6 rocker arm. I have an Edelbrock air gap and Victor Jr for intakes (Any input there, too?), and a Holley super stealth sniper. Its going into a duster with a 4 speed and 3.91 gear with a 29" tall tire. Headers are TTI 1 3/4" primary
The car is not a race car but a hot street car that will go down the track a couple of times a year.
The cam in question is a Comp Cams solid roller with .288 duration (.243 @ .050) and .550 lift. Its on a 110 lobe separation.

Any thoughts on this cam? Too small? Too Big? etc...

Thanks,
Jeff
 
siuauto said:
I am building a stroker 340 with a set of trick flow heads. It's a Molner 3.79 stroke with their H beam rods and Wisco forged pistons. The compression ratio is going to be 10.6:1. OTB Trick Flow Heads with Hughes 1.6 rocker arm. I have an Edelbrock air gap and Victor Jr for intakes (Any input there, too?), and a Holley super stealth sniper. Its going into a duster with a 4 speed and 3.91 gear with a 29" tall tire. Headers are TTI 1 3/4" primary
The car is not a race car but a hot street car that will go down the track a couple of times a year.
The cam in question is a Comp Cams solid roller with .288 duration (.243 @ .050) and .550 lift. Its on a 110 lobe separation.

Any thoughts on this cam? Too small? Too Big? etc...

Thanks,
Jeff
Click to expand...

Not to hijack your thread but are those pistons an off the shelf part number or are they custom?

TIA

EDIT: is that .550 lift with the 1.6 rockers?
 
Newbomb Turk said:
Not to hijack your thread but are those pistons an off the shelf part number or are they custom?

TIA

EDIT: is that .550 lift with the 1.6 rockers?
Click to expand...
They are off-the-shelf pistons (my 10.6:1 is a bit of estimate with the head gaskets I am choosing)

The .550 is with a 1.5 ratio.
 
siuauto said:
I am building a stroker 340 with a set of trick flow heads. It's a Molner 3.79 stroke with their H beam rods and Wisco forged pistons. The compression ratio is going to be 10.6:1. OTB Trick Flow Heads with Hughes 1.6 rocker arm. I have an Edelbrock air gap and Victor Jr for intakes (Any input there, too?), and a Holley super stealth sniper. Its going into a duster with a 4 speed and 3.91 gear with a 29" tall tire. Headers are TTI 1 3/4" primary
The car is not a race car but a hot street car that will go down the track a couple of times a year.
The cam in question is a Comp Cams solid roller with .288 duration (.243 @ .050) and .550 lift. Its on a 110 lobe separation.

Any thoughts on this cam? Too small? Too Big? etc...

Thanks,
Jeff
Click to expand...
I’d use the RPM on the street with that small cam.

In self would run a cam 10*@.050 larger at a min with a single plane.

The cam I don’t like and would look for a tighter LSA, 108 @ a min, 106 would work best IMO for not only more low speed torque but more power across the board.

The lift is lacking but not the end of the world. I myself like to take advantage of the cylinder heads port flow capabilities and lift the valve as much as possible. Cresting maximum flow with valve lift is needed on the street or track but better for max potential at the track IMO. Not a huge deal in getting max lift with the valve to head flow but it’s just grabbing all it’s worth.

The single plane will out HP the dual plane. The lack of low end torque is a killer on the street. On the track, your obviously ignoring it with the stall converter and launch RPM.
 
I myself would use the 1.6 ratio for a .586 lift.

Being a street car with not a lot of gear, I myself would port the RPM & run an inch spacer under the carb.

I think it’ll be an enjoyable ride.
 
I believe you should figure out your dynamic compression ratio with that cam which would require more cam specs. I believe you may need a higher static compression ratio than 10.6:1. This would require different pistons and/or head milling. You can find these compression calculators at wallace racing. It would also be beneficial to have this conversation with your cam grinder as well, but I would figure out your dynamic compression ratio first.
 
What’s the goal for the car? Do you have a number (hp or track time) in mind? Without a goal in mind anyone suggesting a cam profile or manifold choice is kinda pissin in the wind. What’s the car weigh?
 
TT5.9mag said:
What’s the goal for the car? Do you have a number (hp or track time) in mind? Without a goal in mind anyone suggesting a cam profile or manifold choice is kinda pissin in the wind. What’s the car weigh?
Click to expand...
Well, I would love to make around 500-550, which I think it can make. I would give a touch of power for driveability.
 
Never mind- trickflow heads are being used. If you dyno it, let us know! Or track et’s.
 
For a shelf grind, the cam is pretty good for your use. Tighter LSA would be better. Comp Cams charge the same for a custom grind as for a shelf grind.
[1] Do not spend time working out the DCR; it is an absolutely useless number.
[2] Tight-er LSA. On YT, find the video by 'Cattle Dog Garage' that goes for 33 min. It is fairly recent. Sorry, do not know how to link it. It is about LSA selection.
 
Bewy said:
For a shelf grind, the cam is pretty good for your use. Tighter LSA would be better. Comp Cams charge the same for a custom grind as for a shelf grind.
Click to expand...
Nominal charge
Bewy said:
[1] Do not spend time working out the DCR; it is an absolutely useless number.
[2] Tight-er LSA. On YT, find the video by 'Cattle Dog Garage' that goes for 33 min. It is fairly recent. Sorry, do not know how to link it. It is about LSA selection.
Click to expand...
 
Bewy said:
For a shelf grind, the cam is pretty good for your use. Tighter LSA would be better. Comp Cams charge the same for a custom grind as for a shelf grind.
Click to expand...

BS.... When we ordered the comp 260 (a popular off the shelf grind) for the 360 in his ramcharger we simply asked about it being ( I forgot which) tuftride or nitride coated back when wiped flat tappet cam lobes first became a hot topic, it increased the cost of that cam 2-1/2 times over the off the shelf version even though we didn't change a damn thing related to cam specs and it went from a standard off the shelf part to a " custom" cam just because we wanted it coated.
It further frosted my *** to find out that if I was wanting this same cam for a f***ing Ford or Chevy motor it's a standard deal with only a $25 upcharge.
At the time an off the shelf comp 260 for a SB Mopar was something like $160
Simply requesting it to be coated turned it into a $400 cam. I can get exact numbers as I still have the receipt but it's not far from what I posted a few lines above
 
Just as a follow up to the highjack by Newbomb Turk, can you tell me the connecting rod length and the Wiseco piston number that you are using with that 3.79 stroke crank?
Thank You
 
19DART66 said:
Just as a follow-up to the highjack by Newbomb Turk, can you tell me the connecting rod length and the Wiseco piston number that you are using with that 3.79 stroke crank?
Thank You
Click to expand...
The rods are 6.123" and from Molnar. I don't have the pistons with me, they are at the machine shop, so I am not sure of the part number. Let me see if I can get a part number this week.
 
PRH said:
Tighter lsa and self learning EFI often don’t play well together.
Click to expand...
Could you elabrate on this? I didnt know a throttle body injection would affect it? Not sure if it's easily explainable, but if so, I would love to hear it.
 
PRH said:
Tighter lsa and self learning EFI often don’t play well together.
Click to expand...
Does it matter that my self-learning is disabled since I have a professional tuner? Can a good tuner tune around narrow LSA? Or is it not worth the extra you get from an optimal LSA? Thanks in advance.
 
PRH,
Post #13. Richard Holdener tested three cams in an LS engine, EFI, identical for LSA. Purpose of the test was to see what changing LSA did. From memory, LSAs were 108, 112 & 116.
The 108 cam made more average hp & tq.
 
Volaredon, post #16. Be careful when you call BS......
The OP wants a solid ROLLER cam [ not a flat tappet ] & Comp charges the same for a custom or shelf grind.
 
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