|12-17-2012 11:29 PM|
Thank you very much for your service young man, America is the Land of the Free BECAUSE of the brave. May God bless you and keep you safe.
|12-17-2012 11:12 PM|
|12-17-2012 06:29 PM|
|southernculture||you make a very good point. I guess I need to determine how much go I want. I would prefer performance over sound. I have a lunati 10120701 cam and lifter new in the box in my garabe but looked at the specs and just a bit too mild for my application. I had been looking at the 702 and 703 voodoo's and was really leaning towards them, but I just heard the youtube of the mutha thumpr and liked the sound. I know The sound is not really all that important. This is gonna be ina 2500 lb truck and will have a manual trans! I am not in any hurry cause my truck is no where near done, and I dont have to install a cam in a motor as of right now, however I am getting ready to leave for afghanistan and am trying to get a order list for while I am gone. Thanks for the insight!|
|12-17-2012 05:51 PM|
They are compatible with a stock torque converter, although about as far as you'd want to go, while delivering the bottom end torque a 3.08 axle will demand of the engine to make the car go decently from off idle to red line. The fast lift and fairly long LSA will not have the muscle car cam stagger but with the kind of compression you can build, the exhaust note will be sharp. Anybody that needs to know will know this is a motor to be reckoned with. The less informed ones can learn from your tail lights vanishing into the distance.
|12-17-2012 04:03 PM|
|southernculture||I think I am sold on the mother thumper 12-601-4 looks like it will be a good fit spec wise for my motor and I do like the sound at idle! Thanks for the help.|
|12-14-2012 04:52 PM|
Use the comp cams small hyd thumpr cam it will sound good and make pretty good power. But not real smooth at idle it will lope pretty good.
They make good power and sound good dont work on all engines but it sounds like you could run the small thumpr without it any issues. Sep for maybe some carb tuning. Alos most dyno resluts put the thumpr above other cams inhp because the thumpr design produces good peak hp number other cams can produce more average hp. Which is better for truck build with 3.08s
You can hear them on youtube alot of people have vids of the sound.
|12-14-2012 04:34 PM|
|12-14-2012 04:22 PM|
|southernculture||btw the springs that were installed were comp, I am not sure of the specs however the heads were machined to allow .550 lift with these springs. New seats cut and new retainers.|
|12-14-2012 04:15 PM|
|southernculture||I am not sure how much was taken off of the heads, by looking at them there is only raw metal on the corner of both of them.|
|12-14-2012 04:07 PM|
|southernculture||the gap from the top of the piston is .024 to the top of the block. I am the engine assembler. I have not changed the rear gear yet but was planning on a 3.07. The trans I have now is a saginaw 3 speed. I plan on getting a m21. but that is much later. I would rather have rough idle and more power than perfect drive ability it is a rat rod. I am fine with running it higher in rpms, I will be running roller rockers and upgraded pushrods. I dont have a head gasket yet so that gap is still open to arguement, when I did the calculation on the cr it was with a .40 head gasket. I will run pump gas!|
|12-14-2012 03:46 PM|
flat top pistons and vortec heads are probably one of the most popular combos in the past 15 years- it'll work just fine.
|12-14-2012 03:44 PM|
Quench, also called Squish, is the distance from the piston crown to the underside of the cylinder head WITH THE HEAD GASKET IN PLACE and the piston at TDC. It is the sum of the piston deck height and the gasket thickness.
Not trying to give you a hard time CD, just trying to keep the nomenclature correct so that those who are learning from reading these threads will get it correct.
|12-14-2012 03:27 PM|
I have a question for you. What type of gas do you plan on using in this rat rod. I see you have a problem. You are going to use Vortec heads which are 64cc chamber heads. In your short block measure the distance from the top of the block to the top of the piston at TDC. You probably will have .025. This area from the bottom of the head to the top of the piston at TDC is call Quench. The recommended Quench is .040. So if you have .025 you will need a .015 head gasket. This setup will give you around 10.425 compression ratio which is too high for pump gas. If you use a .040 thick head gasket to bring the compression down the engine probably will ping under load. You need to talk to your machinist and motor assembler. The 12cc dish piston should have been recommended for using Vortec heads.
|12-14-2012 03:25 PM|
The 401A3 will be a better match for your goals, provided you run good springs. I'd advise supplementing the cam oiling somehow too, either grooving or face oiling lifters.
|12-14-2012 03:15 PM|
That is a tough order. A cam that idles rough due to a lot of valve duration and valve overlap usually does not allow the engine to produce much cylinder pressure and torque a low RPM and therefore you need a lower rear gear ratio to bring the engine RPM up quicker. The rougher the idle, the worst that condition will be.
Sealed Power CS-113R, solid flat tappet cam will fill that request. It would have a bad (meaning good) idle and produce good low end torque and high end horsepower. Cam range is from 2000 to 5500 RPM.
Sealed power CS-113R solid lifter camshaft specifications:
228 degrees I / 230 degree E valve duration
110 deg. LSA
.395" I / .401" E valve lift with 1.5:1 rocker arms
.421" I / .428" E valve lift with 1.6:1 rocker arms (350 CI engine)
Use with 9.5:1 to 10.0:1 static compression ratio.
Comp Cams 813-16 solid lifters
|This thread has more than 15 replies. Click here to review the whole thread.|