John Curl's Blowtorch preamplifier part III

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Let me guess, level unmatched and sighted listening comparison.
Sorry to say this, but you are insulting somebody which is a lot more equipped, passionate and experienced in measurements than you seem to be and will never be.
Not to say that you are boring like a striped record of a Lady Gaga fanboy, which you clearly share the mode of intellectual functioning.

If I can give you the advice of an old Indian, remove your filter of odd harmonics and your prejudices about things and people.
 
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Yes, all true. I thought people remembered I only have high HP cars. And, if it didnt come from the factory that way, i modified it for as much power as it could stand. The loading on bearings etc is very different from a cruiser car.
ZR1, CTS-V, W12 -- 600-700HP is a lot of fun also. Take the upped ZR1... 0-60 MPH IN 3.2 SEC IN FIRST GEAR! Stock gear ratios. Its the G-forces I am after :)


-RNM

None of those are really super stressed engines. They are all huge displacement undersquare engines making not a lot of HP/L considering they are forced induction.

If you want to look at street car engines living more on the edge, a good example is the Porsche 9A1 4.0L H6 from the GT3. 500 HP from a naturally aspirated 4L 6 cylinder engine, redline 9000 RPM. That's 125 HP/L without a turbo or supercharger.


Still, all these engines are probably closer to a Camry V6 than a top fuel dragster engine.
 
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None of those are really super stressed engines. They are all huge displacement undersquare engines making not a lot of HP/L considering they are forced induction.

If you want to look at street car engines living more on the edge, a good example is the Porsche 9A1 4.0L H6 from the GT3. 500 HP from a naturally aspirated 4L 6 cylinder engine, redline 9000 RPM. That's 125 HP/L without a turbo or supercharger.

Still, all these engines are probably closer to a Camry V6 than a top fuel dragster engine.

4L and 500HP is close to great. espec naturally asper. The ZR1 which won LeMans was estimated to be 900HP nat asper.... before it was handicapped. On another car in my past a 5.0L Ford... I could lift the front wheels off the ground -- street legal. Traction and power.... or my 2.5 L 550HP Nissan with 25 psi turbo and 150HP nitrous kit... would hit Hard! Never had bearing issues though.


-RNM
 
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4L and 500HP is close to great. espec naturally asper. On another car in my past a 5.0L Ford... I could lift the front wheels off the ground -- street legal. Traction and power.... or my 2.5 L 550HP Nissan with 25 psi turbo and 150HP nitrous kit... would hit Hard! Never had bearing issues though.


-RNM

I think it's all in the design. If done correctly and overbuilt like your Nissan 2.5 was, it works out.

BMW S85 V10 and S65 V8 eat rod bearings for lunch, stock. They rev to 8000+ RPM but they really shouldn't do it. People have tried all kinds of additives, different oils, WPC treated bearings, but there is no real fix.
 
... it means no noticeable distortion amp side. And that confirm too the Scott's remark and my personal experience at the old time I designed analog active equalizers with RLC components.
Yes, my bad. Was reading the post too quickly. The thread grows way too fast for me. :D
... JN.... I can test your spkr mods for you.
Thank you.
 
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Sorry to say this, but you are insulting somebody which is a lot more equipped, passionate and experienced in measurements than you seem to be and will never be.
Not to say that you are boring like a striped record of a Lady Gaga fanboy, which you clearly share the mode of intellectual functioning.

If I can give you the advice of an old Indian, remove your filter of odd harmonics and your prejudices about things and people.

:up:
Well said!
 
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Yep, that's where it is at. To be fair, even though the Bentley and CTS-V may be boats, the C6 ZR-1 isn't too heavy and has a power-to-weight ratio that is pretty impressive.

And, I changed the pulley ratios for more boost. It would over power the traction control system. Scary dangerous quick.

Every stock car can be upped or improved... Just like audio gear.

Lots of fun though. Never broke anything or wore out any engine. Best synth oil and additives. Sticking with Mobil One.


-RNM
 
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I missed that if you had said it, there was someone here in Cambridge that had an original Prisoner edition and parked it near MIT where I saw it a few times.
I drove a Lotus Seven to work for a number of years. Lots of fun. Never knew who would be suiting in it when I came out. Not too worried about it getting stolen then no one would know how to start it. Also right hand drive manual in the US is pretty outputting for most. 1200 Lb makes for an impressive power to weight ratio with a modest engine. 1200 cc and 120 HP in the 1970's.
 
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I think it's all in the design. If done correctly and overbuilt like your Nissan 2.5 was, it works out.

BMW S85 V10 and S65 V8 eat rod bearings for lunch, stock. They rev to 8000+ RPM but they really shouldn't do it. People have tried all kinds of additives, different oils, WPC treated bearings, but there is no real fix.

Sounds like a classic case of oil starvation at high rpm. Not enough oil pressure. And/or clearances too tight.

Demian... 10#/HP is a very nice ratio. Quick and agile. CTS-V is about 6#/HP. :eek:


-RNM
 
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If you own one of those BMWs get a Blackstone oil test kit (cheap) to look for copper content..,
This means you have broken thru the first layer of the rod or crank bearing.

Fix it now or pay more later on 🍷

Regards
David

I looked into buying one at one point, so I did a bunch of research. The problem is that the Blackstone analyses don't seem to show elevated copper in many cases. A few people have had really low metals on their reports then throw a rod through the side of the block some months later.

The easiest thing is to just replace the rod bearings as expensive preventative maintenance.
 
Power to weight?

The Arizona Highway Patrol came upon a pile of smoldering metal embedded into the side of a cliff rising above the road at the apex of a curve. the wreckage resembled the site of an airplane crash, but it was a car. The type of car was unidentifiable at the scene. The lab finally figured out what it was and what had happened.

It seems that a guy had somehow gotten hold of a JATO unit (Jet Assisted Take Off – actually a solid fuel rocket) that is used to give heavy military transport planes an extra 'push' for taking off from short airfields. He had driven his Chevy Impala out into the desert and found a long, straight stretch of road. Then he attached the JATO unit to his car, jumped in, got up some speed and fired off the JATO!

The facts, as best could be determined, are that the operator of the 1967 Impala hit JATO ignition at a distance of approximately 3.0 miles from the crash site. This was established by the prominent scorched and melted asphalt at that location. The JATO, if operating properly, would have reached maximum thrust within five seconds, causing the Chevy to reach speeds well in excess of 350 MPH, continuing at full power for an additional 20–25 seconds. The driver, soon to be pilot, most likely would have experienced G-forces usually reserved for dog-fighting F-14 jocks under full afterburners, basically causing him to become insignificant for the remainder of the event. However, the automobile remained on the straight highway for about 2.5 miles (15–20 seconds) before the driver applied and completely melted the brakes, blowing the tires and leaving thick rubber marks on the road surface, then becoming airborne for an additional 1.4 miles and impacting the cliff face at a height of 125 feet, leaving a blackened crater 3 feet deep in the rock.

Most of the driver's remains were not recoverable; however, small fragments of bone, teeth and hair were extracted from the crater, and fingernail and bone shards were removed from a piece of debris believed to be a portion of the steering wheel.

Of course this is fiction.
 
Also right hand drive manual in the US is pretty outputting for most.

I assume clutch/brake/gas were not shuffled. When I rented in the UK I asked for an automatic just to make the three days less hassle, the guy behind the counter literally said what kind of man are you. I remember the foot pedals at least were in the same order.

I see it's time for a car break, relieves the pressure so to speak.
 
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Demian: Mine had a tweaked Mazda 13B rotary in. Thick end of 200HP. Really low CoG. Sadly getting it running co incided with other parts of my life going wrong.



If I had another would be a 1760 ford X-flow. I can't afford a BDA and sound wise the x-flow is the next best. Sometimes for enjoyment less is more.


@richard. This is more your sort of car. Triple 0-100-0mph World Record Holders . Amazing but too wide to enjoy on UK roads.
 
It amazes me to no end that the great perfomance of BMW,s under 50k mileage🙂 has now this issue hanging over their owners head.

What happened to German engineering at BMW ??

And I do own (older era BMW ) and have rebuilt a few motors from this maker

Regards
David

It's only the S85 and S65 engines that have this problem, so last gen M3 and 2 generation old M5. The S65 has the problem because it is the S85 with 2 cylinders chopped off.
 
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