Thread: HP Vs. Dollar, Bang for Buck...

Tweet

Petersen Pub. Co. used to print a "Hot Rod Annual" which I tried to collect and somewhere around 1971 or so there was an extensive set of dyno runs by Iskederian Eng. on modifying the SBC 350. They got it up to over 480 H.P. without nitrous or any forced induction but in terms of (HP/$) the simple change of the stock cam for a mild Isky cam gave the most increase of about 63 HP for the price of a reground cam. For many years I was hooked on the idea that all you had to do was rebuild a 350 and change the cam. However, when you read the dyno charts carefully you can see that the low rpm torque drops off considerably when the cam is selected for more HP in the 4000 rpm range. That is why I now look at the low rpm torque since that will be the operating range when cruising in 4th gear OD. I just found the old article and the HP gain was 62.3 HP for the $55 Isky 280-H cam with a peak HP (I assume at the flywheel since their stock baseline was 293.7 HP at 4000 rpm.) With the only change being to the 280-H cam they got 356.0 HP at 5500 rpm. For comparison, the stock cam produced 170.8 HP at 2500 rpm but with the 280-H they got 158.7 HP at 2500 rpm. Using their old price that was (62.3 HP/$55)=1.13 HP/$. Probably a similar cam can be bought for even less today from Speedway, but of course that is the old way of measuring the HP at the flywheel and it is obvious that more HP at higher rpm degrades the low rpm HP. This is just playing with numbers but you said (HP/$). Overall I would agree with lt1s10 that adding a Roots-type blower would be the best way to add a lot of HP, but then what about overheating and crank bearings?

Don Shillady
Retired Scientist/teen rodder

Sorry fellas, IMO if all you want is the best bang for the $ then you cannot come close to nitrous. Period. And I am talking about total expended dollars and effort here, not just parts cost.

That said, the fastest way to wrecking the average engine is nitrous also. But that was not the quest here ..............

Kitz

Lets call NASA and let them analize it! There is just to many factors to come to a conclusion. Short term / long term / pay me now or pay me later ect ect ect.

1big engine. 2 big engine with a blower. 3 bigger engine. 4 bigger engine with a blower and nos .did i say a big engine. i love my 10.5 cr 630+ big block but a big block with a blower is not bad

Originally Posted by pat mccarthy

1big engine. 2 big engine with a blower. 3 bigger engine. 4 bigger engine with a blower and nos .did i say a big engine. i love my 10.5 cr 630+ big block but a big block with a blower is not bad

Pat your a poet and did'nt know it.

ahh bigger just makes it easier try harder!

Originally Posted by erik erikson

Pat your a poet and did'nt know it.

Originally Posted by gassersrule_196

ahh bigger just makes it easier try harder!

if you ever had over 700 qt nail you to the driver seat you would never go back to them small blocks i stop trying hard long ago. just get them bigger

i wish i could get that outta my small block i push it at 500ftlbs tq at 4000 rpms... if i could fit a big block in my mustang without major mods... i'd do it in a heart beat

ah......... nothin an ls6 454 wont cure