Originally Posted By: robertway
Originally Posted By: OVERK1LL
Originally Posted By: A_Harman
For Chrysler's 6.4 Hemi:
470 hp / 392 cubic inches = 1.20 hp/cid
For Chevy's 7.0 LS7:
505 hp / 427 cubic inches = 1.18 hp/cid
Come on Chrysler, do whatever you need to do to bore and stroke the Hemi to 426!
I agree, though need to mention:
For Ford's 5.0L BOSS 302:
444HP / 302 cubic inches = 1.47HP/cid
Ford's Boss Engine needs to spin to 7400rpm to get that 444HP (7500rpm redline)> Not saying that is a bad thing just pointing out it is a high revving track car. It has no more torque, and actually has a little less torque than the regular 302 Coyote in the Mustang GTs and it comes on 250rpm later than the regular engine which tells me it may have less torque down low compared to the GT Engine. Now the fun part is it is a fully forged rotating assembly so drop a twin-screw on top of it and OMG!!! But at an 11:1 compression ratio I would think boost would be somewhat limited on pump gas, but I haven't been following what folks are doing on the new 302 as the GT version is 11:1 also and guys are boosting those already.
The 393 HEMI is all about torque, over 400lb/ft from 2500-6000rpm peaking at 470@4250rpm and it needs top as the car is massive/beasty. If one wanted to, you could drop a CAI in the car and some upgraded valvle spring and once the car could be tuned up the rev limiter to 7000rpm and the 392 would pump out 500+ bhp no problem.
The LS7 in the Z06 is very comparable in torque curve to the 392 albiet with more displacement and a higher compression ration of 11:1 to the 392 10.3:1. It gets to 400lb/ft by about 2500rpm and doesn't fall below 400 until 7000rpm at least on the GM Performance Parts page that shows the engine dyno and actually winds the engine to 8000rpm. It does the same peak torque as the 392 with 470lb/ft but it comes later at about 5100 but holds that flat until 6100rpm before falling off.
I'd be happy to have any of the engines under the hood and what Ford has done with only 5 liters is very impressive, it really speaks to the efficiency of the design. It trumps the 392 and the LS7 in both hp/ci and tq/ci at peak but I want my torque down low and need it with the weight of this car.
In the curb weight/HP game the Z06 is the monster by a long shot while the 392 and the Boss trade 2nd and 3rd place depending upon wt/hp or wt/tq
Z06 6.3:1 wt/hp (3199lbs/505hp 6.8:1 wt/tq (3199lbs/470lbft)
Boss 302 8.2:1 wt/hp (3632lbs/444hp) 9.6:1 wt/tq (3632lbs/380lbft)
SRT8 392 9.1:1 wt/hp (4257lbs/470hp) 9.1:1 wt/tq (4257lbs/470lbft)
Why did I type all this, not sure, I was bored and it was interesting to look at the dynos and weights. I'd be happy to have any of these cars in my garage but right now with four young kids, the Challenger is the only one that can haul them all at the same time, with the wife following behind in the minivan of course.
As an aside, the Advanced Auto Parts Castrol sale included two Fram Extra Guard 3x filters, I normally use the PurOne filters on all the cars and was wondering if the Frams were [censored] or ok to use for 5000miles each.
Is this why most high revving-high performance engines always recommend thicker oils (40,50 weights) and warn against using thinner weights when racing/driving extended high speeds?
