I need schooling - old vs. new engines

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I would be curious to hear what your cam specs are. If you get a chance to look them up.

I did do some digging on the Comp website and the biggest cam I could find for a non-VVT Hemi was a Stage 3 cam with 277/284 advertised duration, 224/234 duration at 0.050 lift, 0.632/0.619 lift and a 115 LSA.

But you can't be making 650+ hp with that cam can you? Seems like a pretty small cam to me. That's smaller than the 380hp crate motor cam, duration wise.
From the cam card:
1st of all it says "special grind" on the card. Comp may only sell it to B.E.S. who can turn around and sell it to me.
Part # 112-000-11
Lift- Intake .605 Exhaust .605
Duration @.006- Intake 297 Exhaust 305
Duration @.050- Intake 247 Exhaust 254
113 center line
Lobe separation- 115.0
 
Advantage #16. A Stock G3 Hemi weighs approx 70 lbs less than a comparable stock small block. (not personally verified)
 
Advantage #16. A Stock G3 Hemi weighs approx 70 lbs less than a comparable stock small block. (not personally verified)

I've heard they are lighter, too, but my gut says that is false. Block sure seems to have to weight more with the full skirts and enclosed cam tunnel. But I don't have anything to refute the claim either.
 
I've heard they are lighter, too, but my gut says that is false. Block sure seems to have to weight more with the full skirts and enclosed cam tunnel. But I don't have anything to refute the claim either.

If it was designed with Finite Element Analysis which existed in the 1990s it should be much stronger than LA/Magnum blocks without having to weigh more. Also remember the heads are aluminum, they are physically bigger than a wedge but the material makes them lighter overall. Even so I'm pretty sure a wedge-head SBM with aluminum top end still weighs less than a G3 Hemi.

I think a big "fail" for Chrysler was never making a production aluminum-block version for cars like GM did with the LQ/LS.
 
Interesting thread and good input from all. Opinions can become heated, with the passage of time, the rose we remember the thorns we often forget. As someone who has run street/strip LAs and Gen II Hemis and is looking to possibly update to supercharged Gen III Hemi power, as always it depends what you want ot use the vehicle for and what you can afford and are prepared to put up with.

LA:

I love LA engines and have gone fast with NA, stock stroke pump, gas combos over 25 yrs ago on the street. Were they great drivers? Not really. Its now expensive to build a decent one, blocks not much good long term above 600HP, would need decent 4500-5500K stall, non lock up converters, stiffer CR, bigger cams, stiffer rear gearing, the usual maladies apply. The LA platform, although improved, is not as well embraced by the aftermarket compared to the Gen III - there is a reason for this. Especially blocks.

Gen II Hemi:

I run a pump gas 572 Hemi in my street/strip car. It's a blast. Makes great, reliable HP/TQ on pump gas. Are there cheaper ways to make the power? Yes. Perhaps more efficient ways? Definately yes. One issue is the Gen II Hemi also has less aftermarket support and what is there is expensive, esp blocks and valvetrains; low demand = low volume = $$$.

Looking back, the Hemi was DESIGNED as a race engine from the outset and OEM focus was on developing it a such. The Max Wedge is the exception of course. Even Chrysler realised that they needed to develop the Hemis breathing advantage. The Hemi was compromised to be put in street cars b/w 66-71; common at the time was adding a set of headers and a cam and it made them very fast on the street back then. The Hemi's race record speaks for itself and still does. Racers like Landy, Sox & Martin, Leal & Co were'nt stupid. The knew the platform that the Hemi was and made it even better. So did TF. I love wedges esp the 6 packs, however the Hemi had the reputation of being fast at the time - because it WAS. Street based wedges with 6 packs were fast, but well sorted/dialled Hemi with solid cams and headers were way over 500HP on the street. Production wedges (even 6 paks) were out of gas when the Hemi was just winding up.

Did it have its issues? Absolutely. EVERY engine design has compromises. Since that time, the aftermarket has changed a lot and yes Wedges have come a LONG way today and make serious HP/TQ now.. Advanced cyl head design, esp in the chambers and ports have changed the game significantly, not to mention big cubic inches. Both designs have inherent design advantages and disadvantages, lets remember WHEN they were designed and how. Choose your poison and spend your dineros.

Having said all this - if I had my way over in my current ride, Id have a.....

Gen III Hemi:

Specifically, a 1000+HP to the tire, supercharged Gen III Hemi. Not cheap either, but WHY ???

  • aftermarket parts availability
  • more modern, efficient design capitalizing on computers and decades of engine design experience
  • capitalizing on aftermarket tuners intellectual property, knowledge and experience.
  • less mass over the front end (a big one)
  • double OD ZF 8 speed, less ratio drop b/w gears, lockup converter ( a huge one)
  • less rear gear needed (another big one)
  • o ringed seals
  • hyd roller cams and stable valvetrains
  • COP/dual plug
  • very good production based cyl heads, BGE blocks and cranks
  • cyl to cyl tunable EFI
  • cheaply and widely available
  • serious, RELIABLE power over the long haul.
The Gen III also has some issues regardless of what the platform has to offer.

Once again, it depends on what you want to do with the car, what you can afford and your preferences. For me this platform would enable me to better USE the car, have my cake and eat it so to speak. No stiff gearing or looser converters. Pump gas. Killer HP/TQ. Modern trans. Driveability. I'm not getting any younger and have been at it for decades - sometimes one has to embrace things that the modern age has given us.

Kinda long winded....but my 2c
 
Interesting thread and good input from all. Opinions can become heated, with the passage of time, the rose we remember the thorns we often forget. As someone who has run street/strip LAs and Gen II Hemis and is looking to possibly update to supercharged Gen III Hemi power, as always it depends what you want ot use the vehicle for and what you can afford and are prepared to put up with.

LA:

I love LA engines and have gone fast with NA, stock stroke pump, gas combos over 25 yrs ago on the street. Were they great drivers? Not really. Its now expensive to build a decent one, blocks not much good long term above 600HP, would need decent 4500-5500K stall, non lock up converters, stiffer CR, bigger cams, stiffer rear gearing, the usual maladies apply. The LA platform, although improved, is not as well embraced by the aftermarket compared to the Gen III - there is a reason for this. Especially blocks.

Gen II Hemi:

I run a pump gas 572 Hemi in my street/strip car. It's a blast. Makes great, reliable HP/TQ on pump gas. Are there cheaper ways to make the power? Yes. Perhaps more efficient ways? Definately yes. One issue is the Gen II Hemi also has less aftermarket support and what is there is expensive, esp blocks and valvetrains; low demand = low volume = $$$.

Looking back, the Hemi was DESIGNED as a race engine from the outset and OEM focus was on developing it a such. The Max Wedge is the exception of course. Even Chrysler realised that they needed to develop the Hemis breathing advantage. The Hemi was compromised to be put in street cars b/w 66-71; common at the time was adding a set of headers and a cam and it made them very fast on the street back then. The Hemi's race record speaks for itself and still does. Racers like Landy, Sox & Martin, Leal & Co were'nt stupid. The knew the platform that the Hemi was and made it even better. So did TF. I love wedges esp the 6 packs, however the Hemi had the reputation of being fast at the time - because it WAS. Street based wedges with 6 packs were fast, but well sorted/dialled Hemi with solid cams and headers were way over 500HP on the street. Production wedges (even 6 paks) were out of gas when the Hemi was just winding up.

Did it have its issues? Absolutely. EVERY engine design has compromises. Since that time, the aftermarket has changed a lot and yes Wedges have come a LONG way today and make serious HP/TQ now.. Advanced cyl head design, esp in the chambers and ports have changed the game significantly, not to mention big cubic inches. Both designs have inherent design advantages and disadvantages, lets remember WHEN they were designed and how. Choose your poison and spend your dineros.

Having said all this - if I had my way over in my current ride, Id have a.....

Gen III Hemi:

Specifically, a 1000+HP to the tire, supercharged Gen III Hemi. Not cheap either, but WHY ???

  • aftermarket parts availability
  • more modern, efficient design capitalizing on computers and decades of engine design experience
  • capitalizing on aftermarket tuners intellectual property, knowledge and experience.
  • less mass over the front end (a big one)
  • double OD ZF 8 speed, less ratio drop b/w gears, lockup converter ( a huge one)
  • less rear gear needed (another big one)
  • o ringed seals
  • hyd roller cams and stable valvetrains
  • COP/dual plug
  • very good production based cyl heads, BGE blocks and cranks
  • cyl to cyl tunable EFI
  • cheaply and widely available
  • serious, RELIABLE power over the long haul.
The Gen III also has some issues regardless of what the platform has to offer.

Once again, it depends on what you want to do with the car, what you can afford and your preferences. For me this platform would enable me to better USE the car, have my cake and eat it so to speak. No stiff gearing or looser converters. Pump gas. Killer HP/TQ. Modern trans. Driveability. I'm not getting any younger and have been at it for decades - sometimes one has to embrace things that the modern age has given us.

Kinda long winded....but my 2c

Good stuff. Just a note to add and not sure if they're readily available in Australia but the 5.2/5.9L Magnum engines have helped extend the practical usage of SBM engines. Primarily in the short block there are many improvements to the LA platform; blocks, crankshafts, connecting rods and pistons are stronger with better materials, more precise machining, tighter tolerances, lighter weight (mainly pistons) and interchangeability with LA-based parts aside from oil supply to stock-type shaft-mounted rocker arms. They're also factory equipped with roller lifters that typically don't require replacement which saves a lot of expense.

Here in the U.S., Magnum engines are dirt cheap at junkyards and the factory short blocks show little to no wear even with over 150,000 miles on them thanks to the factory EFI and tighter machining tolerances. The factory pistons also have less of a dish than LA versions and sit higher in the bores at TDC allowing for higher compression ratios with typical aftermarket heads (around 9.5:1 is pretty realistic).
 
Man I'm an old school purist when it comes to old cars with older engines. But I LOVE the Gen III hemi and 8 speed in my Ram truck. I can't imagine how much fun it would be in my 68 Barracuda
 
Years ago Tony Bischoff built me a long block 5.7 based 414 stroker for racing. Last year I had to replace the block after 8 years of bracket racing it due to a crack. Block at the junkyard cost me $200 and still had crosshatch. Gen III parts are getting cheaper and much more readily available.
 
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Ron Reagle Im as old school as one can get, hell my ride still looks like an early 80s build from the outside.But I have to weigh up the pros and cons of each platform and take into consideration what I want from the car moving forward.
 
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