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First Shelby GT350 in the 11's quarter-mile (11.96 @ 116 MPH)

Nataphen

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Do we know if Ford Performance or some other gear manufacturer has any plans to make lower gears for the IRS 8.8? I'm seriously wanting this to be one of my first mods for my GT350, and not just for drag racing. I think a shorter gear would make this car so much more fun on the street because it would allow more trips to the rev limiter without more trips to the impound. ;)

I read somewhere that Ford mentioned a 4.10 in the works. I can't remember the source, nor do I know how reliable that is. I'll have to search for it.
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nametoshowothers

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Agree but disagree. It's higher rpm over the z28 is due to shorter stroke, lighter mass
the maximum rpm for the piston is based on bore, stroke, piston weight and crank design.

the maximum rpm for the valve train is based on the mass of the valve components, clearance (tolerances), springs and cam profile. The push rods and large valves on a 2 valve per cylinder all cause the maximum engine rpm to be limited compared to a 4 valve (small valves but more total valve area) overhead cam. The pushrod add alot of mass and flex in the valve train that limits RPM.

maximum engine RPM is the lower of the maximum allowable engine RPM from piston/crank/stroke consideration and the maximum allowable based on the valve train.
 

Voodooo

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the maximum rpm for the piston is based on bore, stroke, piston weight and crank design.

the maximum rpm for the valve train is based on the mass of the valve components, clearance (tolerances), springs and cam profile. The push rods and large valves on a 2 valve per cylinder all cause the maximum engine rpm to be limited compared to a 4 valve (small valves but more total valve area) overhead cam. The pushrod add alot of mass and flex in the valve train that limits RPM.

maximum engine RPM is the lower of the maximum allowable engine RPM from piston/crank/stroke consideration and the maximum allowable based on the valve train.
Yeah I pretty much told him that. Don't try telling me a push rod motor can't rev. My dad and I built a 289 some years back for his 63 1/2 falcon sprint that spun to 9500 rpm. So yes it can be done.
 
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robb

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Compare the torque curves on the dyno graph. Not saying it makes less power/trq, saying it makes less torque down low.


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That makes sense. Thanks for clarifying. :)
 

chuckty101

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Yeah I pretty much told him that. Don't try telling me a push rod motor can't rev. My dad and I built a 289 some years back for his 63 1/2 falcon sprint that spun to 9500 rpm. So yes it can be done.
On a production engine that needs to run for 200,000 miles, I don't think a 9500 rpm pushrod engine would last very long. Just watch nascar pushrod engines turning up to 9000 rpm are max out after 600/700 miles.
 

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Rob@Evolution

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That was a first gear launch. We were leaving @ 6-7k and speaking with the driver he was unsure of the rpm at the traps being he was focusing on driving. Until we start logging it's anyone's guess at this point but I will be sure to get an answer when we go back out . :shrug:
 

Voodooo

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On a production engine that needs to run for 200,000 miles, I don't think a 9500 rpm pushrod engine would last very long. Just watch nascar pushrod engines turning up to 9000 rpm are max out after 600/700 miles.
Why are you even bringing that up. I thought the argument was that a push Rod engine couldn't rev high and I'm just stating that it can. NASCAR is for hillbillies. NHRA IS a real power.
I have a 401 svo blocked engine with a 3.75 stroke and 4.125 bore. I run a Yates head and I rev it to 9700 rpm. What's your point. Shifting through a Jericho DR4 trans.
 

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MadCow

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Actually not

The push rod engine is relatively low tech compared to the overhead cam engine. From a mechanical engineering perspective the overhead engine is more advanced able to operate with greater precision on valve timing, rpm, cam profiles etc. have not seen one formula 1 team planning to move to the new fangled pushrod engine technology.

Push rod engine is good for one thing only and that is it is cheaper and smaller footprint for the same piston displacement


By the way some italian dude tried to build flying machines including a helicopter. So therefor with you logic the helicopter is centuries older than the car. By the way his name started with Leonardo




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I didn't say low or high tech or which one is better. I just said OHC is older. Sometimes earlier designs are superior to the ones that replace them. And yes, being smaller relative to displacement is one of the OHV engine's best characteristics. What's best is all about application. Sometimes a compact size or light weight is important. Sometimes it isn't.

As for da Vinci, the key word you used is "tried". Is there proof that he flew? I heard ancient Egyptians flew or at least "tried". I heard antediluvians traveled in space. But is there any hard evidence? Did da Vinci achieve powered flight or a glide or a controlled fall? How about that time a man fell off a cliff centuries before da Vinci? Did he fly? Did his tailor inadvertently invent the hang glider or the parachute? And how much do da Vinci's machines have in common with a modern aircraft? Maybe as much as the ancient carts or chariots have in common with a modern car so maybe the car came first. What about 1000's of years ago when that log went rolling down a hill. Was that a wheel?

So now that we are about as far off topic as you can get for a GT350 running 11's, I hope you understand my point and the simple fact that OHC is older than OHV.
 

9secondko

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@evo

Are you guys going to details a package that allows for average Joe's to purchase from you in order to duplicate what you do on the track? (I know you've still got some testing and work to do. Just wondering if this is in your collective thought process).
 

chuckty101

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Why are you even bringing that up. I thought the argument was that a push Rod engine couldn't rev high and I'm just stating that it can. NASCAR is for hillbillies. NHRA IS a real power.
I have a 401 svo blocked engine with a 3.75 stroke and 4.125 bore. I run a Yates head and I rev it to 9700 rpm. What's your point. Shifting through a Jericho DR4 trans.
Fastest NHRA Super Stocker of All time is OHC engine.

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nastang87xx

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Why are you even bringing that up. I thought the argument was that a push Rod engine couldn't rev high and I'm just stating that it can.
This is true. As per the NASCAR comment, they are 10,500 RPM capable and are limited to 9 - 9500 depending on event, season, and power restrictions.

Gittin Jr's. Formula D car (RIP car! :() was a Roush Yates custom engine based off of a NASCAR platform that was 9200 RPM capable. They revved it to 8400 - 8600 for longevity and granted runs only lasted less than a minute, they rarely had to replace anything on the bottom end.
 

Voodooo

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