Estimations for 1/4?

Jerry M

Member
Apr 11, 2019
38
Hey, I’m currently in the process of making my camaro better on the strip. I’m building a 388 stroker, nothing real special, carbureted with vortec heads. It will have hooker headers and 2.5 inch dual exhausts and a comp cams mutha thrumpr hydraulic roller. It’s not exactly a real performance cam, more of a noisy cam. I’m looking to see what some estimations for numbers like HP, Torque, and 1/4 are. I just want to see what others are running with similar setups to get an idea before it’s actually up and running. 388 stroker, 700r4, 3.73 rear gears. 255 standard everyday tires for now (plan on upgrading to something stickier) so if you have a similar setup or have seen one run, what are some times you’re making?
 

ULTM8Z

Veteran Member
May 19, 2000
11,118
Los Angeles
I don't know what cam that is, but unless you're planning a low end torque monster, Vortec heads could be a choke point for a 388... in which case badazz is probably closer to being correct.
 

76z28

Veteran Member
Jun 29, 2009
2,886
bakersfield
I would do away with that cam; however, you're looking in the high 13s I would say.
Low 13s if you get DR and hook it.
 

RS1979

Veteran Member
Lifetime Gold Member
Jun 18, 2013
4,055
Memphis, TN
What else is in the engine? Compression? Intake and carb? Like 76 said, I'd put another cam in it. Those cams are designed to sound good not really for racing. You can put a 280H Comp Cam in it and get more power.
 

jeff swisher

Veteran Member
Apr 26, 2018
2,001
Yukon Oklahoma
Buddy used a muther thumper flat tappet in a 355" sbc in a boat. It would out run a few of his buddies.
67 MPH GPS.
I think Joe Sherman tried some of the thumper lines when they came out and he said they will make some HP.

If you look at the specs of the Roller Mutha Thumper they really are not too bad.
235-249 @ .050 for intake and exhaust. Lift is .522" on intake side and .509" on the exhaust.
And on a 107LSA I have no idea where the intake valve closes.

Seriously that does not look all that bad on paper like that.
I ran a solid flat tappet that was a Herbert grind in a 350" it was 235-245@ .050 and .500" lift both sides on a 108LSA. Lashed at .025" so .475" lift.
Went 11.50's had a crap load of compression and ported and milled 186 heads.
2780 lb car 3000 stall and 3.70 gear.
I still had working power brakes with it no extra vacuum crap either. small runner heads.

I think that cam would do nicely in a 388 and research Dyno Thumper cam sbc.. The little Thumper roller will spin cleanly to 7000 rpm.


Yes there is a lot of duration compared to the amount of lift. The way i see that is it is probably a sort of lazy lobe.
But I can't confirm that.. Lazy lobes like to rev and that overlap of that cam can really start pulling hard on the intake tract filling the cylinders nicely at high RPM.

And lazy lobes last a long time.. They do not beat the valvetrain to death.

I say run it and see.
Should be solid in the 12's if it is under 3600 race weight.
But get the tune off or you can't make it hook then you could be stuck trying to get out of the 13's or 14's.

You say better on the strip is the goal.
I assume you have ran it???
 

jeff swisher

Veteran Member
Apr 26, 2018
2,001
Yukon Oklahoma
“Everyday tires”...he’s not going down the strip quick

Yea it is tough to do. I could not full throttle my car with the 60,000 mile rated radials Uniroyal tiger paws.
275-60-15. But I did muster up a 1.8 60 foot time once I stuck a spool into the car.
Still no full throttle deals until 1/2 way through second gear. and ran a 12.51 ET.
It was 2980 lb race weight. that helped things out.

I go drag radials now..as there are stock V6 and 4 cylinder cars that would clean my clock.
 




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