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S197 3V Fabman's build; How did we get here? Build Thread

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Fabman

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Ahh, yes forgot about the ABS... those pagid pads are really grabby so without abs it must have been hard to avoid locking up.
Yeah, got exciting several times....the stopping power of these brakes is amazing. Can't wait to get the ABS going.
 

Mad Hatter

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A track buddies full Cortex 1967 Notchback with a ford racing 427 used RSL29 pads to avoid locking up all the time. The Pagid red ones are just too much with out ABS.
 
373 is what the Boss comes with, which seems perfect to me. My friend's '10 Camaro SS had a 355 rear gear and He could tell the difference right away when He rode in my Boss...My hi-school buddy had 411's in his '69 440 Magnum Dodge Coronet RT and that thing kicked butt!!!
 
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302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
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Love big block 440 Magnum MOPAR sound. Each Detroit Big 3 V8 Power has its own unique sound.

Never thought I’d own a MOPAR big block . .. but does a L6 6.7L Cummins Turbo Diesel count?
 

JDee

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373 is what the Boss comes with, which seems perfect to me. My friend's '10 Camaro SS had a 327 rear gear and He could tell the difference right away when He rode in my Boss...My hi-school buddy had 411's in his '69 440 Magnum Dodge Coronet RT and that thing kicked butt!!!

Except it's not though, at least not on the 3 tracks I most often run. On every one of those tracks I am running out of revs in more than one place and need to shift near the end of a straight, whereas if I had 3.55's I could avoid that problem. That's probably my next thing, 3.55s along with a diff cooler. Oh, what I would give to have an old school quick change rear end.....
 

racer47

Still winning after 30+ years
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Fabman

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No personal knowledge, but I recall reading that the tooth count for a 3.90 made it less desireable than a 3.73 for some reason. Ford Performance doesn't sell a 3.90 8.8" set.
I wonder why?
 

Fabman

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Mad Hatter

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I got a line on take off Dunlop 300/680-18 slicks, pretty tall, wonder what they will be like as the effect on gearing is fairly dramatic (over a inch taller). Finding my 3.73 a little short as well.. The local GT3 cup Gentlemen racers (really just rich guys, dont know about the gentlemen part) use them for one race and toss them.
 

Fabman

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I got a line on take off Dunlop 300/680-18 slicks, pretty tall, wonder what they will be like as the effect on gearing is fairly dramatic (over a inch taller). Finding my 3.73 a little short as well.. The local GT3 cup Gentlemen racers (really just rich guys, dont know about the gentlemen part) use them for one race and toss them.
This site is super helpful:
 

Fabman

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I got a line on take off Dunlop 300/680-18 slicks, pretty tall, wonder what they will be like as the effect on gearing is fairly dramatic (over a inch taller). Finding my 3.73 a little short as well.. The local GT3 cup Gentlemen racers (really just rich guys, dont know about the gentlemen part) use them for one race and toss them.
Free is good, I like free.
They will certainly feel different and you may need to re spring the car to take full advantage of them, especially if they are much gripper than what you are using now. The carcass is also different than a DOT and taller too.
It will be interesting to hear how they work for you.
 

Boone

Professional Thread Killer
I use the site below to get a feel for tranny and rear end set ups. You can save different transmissions on the site.


Better yet, I created an Excel spreadsheet that calculated RPM with various tranny, rear gear, and tire size combinations. I would review video and enter corner and straight speeds for every track I go to, and the corresponding RPM would output. Some random nice person encrypted the files on my computer for me without me even asking them to a while back, and they only wanted some bitcoin after performing this random act of kindness. The drive got wiped.

For Fabman, I think 3.90 sounds right. He's done his homework on what speed he wants to hit and what RPM he can live with. Lap times likely won't change much either way with the small gain on the straight and the small loss coming out of corners, but the motor is more likely to survive. With 3.55s, he would loose a lot of time in the twisties by lowering his rpm on corner exit. Same with 3.73s to a lesser extent. I experienced this firsthand when I went from 4.10 to 3.55 so I could stay in 4th on the long straights of VIR.
 

Fabman

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For Fabman, I think 3.90 sounds right. He's done his homework on what speed he wants to hit and what RPM he can live with. Lap times likely won't change much either way with the small gain on the straight and the small loss coming out of corners, but the motor is more likely to survive. With 3.55s, he would loose a lot of time in the twisties by lowering his rpm on corner exit. Same with 3.73s to a lesser extent. I experienced this firsthand when I went from 4.10 to 3.55 so I could stay in 4th on the long straights of VIR.
Nailed it.
 

ArizonaBOSS

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Sal, suppose you were to plumb the bottom drain of the petersen can back to the oil pan? You could put a one way check valve in the line so any crankcase pressure keeps it closed but off throttle it would allow the oil to flow back.
@captdistraction did that on his build and can provide some pics. The Petersen can has a drain fitting already threaded. Mine does that too, but not as much. I'll have to inspect what's in mine after the shakedown day soon.
 

Fabman

Dances with Racecars
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@captdistraction did that on his build and can provide some pics. The Petersen can has a drain fitting already threaded. Mine does that too, but not as much. I'll have to inspect what's in mine after the shakedown day soon.
I had that on my 3 valve but this pan doesn't have a bung in it so no place for the oil to re enter the engine.
 

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