Prefix 9 0 liter

[Arizona Vipers]

Shoutout to Prefix for building me an amazing motor. I've been running their 9 liter hard all over the country for over 3 years now. 2 years ago they upgraded the motor with high compression pistons and some other goodies, and I've beat the hell out of it and never had any issues. This is a very rare thing when you are talking 800whp naturally aspirated power, and all hard track miles. This thing lives at high RPM and full throttle. If you had this motor built for your daily or average track use, it would probably last longer than you.

[MISSEDSHIFT09]

Great to know! I’m a solid mix of abundant spirited street use and HARD track use. Now, I’m stock in the engine dept., but three years, 24k miles and dozens of track days later, I’ve had zero trouble! FCA, or whoever the hell they are now gave us something solid to work with!
Glad to hear of some legit long term track experience with a built motor for all of us to reference and consider as new technology gives our track companions the edge!

[Bruce H.]

Good to hear. I have two friends also installing them this month.

[Loud]

Love it. AZ is getting popular with the 9L's. I need to get mine to sound like yours ;)

[StrokerAce]

800whp is rwhp, correct?

[Loud]

800whp is rwhp, correct?

Yes, since they are all RWD.

[Arizona Vipers]

Love it. AZ is getting popular with the 9L's. I need to get mine to sound like yours ;)

Do it! hehe. Car is going to UMS Tuning today to fix the exhaust. Gonna do 3.5" straight pipe titanium

[J TNT]

That's awesome reliability and performance , Prefix is Top Tier !!!
Their 2021 Mopar Drag Pak is another cool build . Enjoy !

[StrokerAce]

Yes, since they are all RWD.


Vipers are rear wheel drive? Well I'll be damned.

I thought he forgot a letter like rwhp or fwhp. R for rear and F for fly.

[Fastbusy]

Arizona, I'm in the process of having a 9.0L installed. I was wondering if you could comment, in your experience, how the stock differential handles the extra 9.0L power at the track (road course). I saw a recent thread suggesting some room for improvement at the track with the 9.0L + stock differential. I suppose others might have a view on this as well.

[Arizona Vipers]

Arizona, I'm in the process of having a 9.0L installed. I was wondering if you could comment, in your experience, how the stock differential handles the extra 9.0L power at the track (road course). I saw a recent thread suggesting some room for improvement at the track with the 9.0L + stock differential. I suppose others might have a view on this as well.

The stock diff can handle like 1500 horsepower according to Calvo. The problem I had at COTA is the halfshaft popped out, this has happened before on high hp Calvo cars, he said it's due to soft bushings, we are getting solid ones made for it now. It's probably the last think you'll need to worry about!

[racegate]

How many track miles do you think you have on the engine?

[est8esq]

I met a gentleman at Sebring a couple weeks ago (when I ran my PB (personal best), "Drexler" diff thread). I can't recall his name. He was running in a different group, but had the 9 liter extreme. Great story how he bought his Viper while at Prefix and upgraded to the bigger motor.
He was running 2:17's against my 2:11 (pb), but he was hitting 160 mph against my 150 mph on the back straight. That is a REMARKABLE difference in straighline speed AND I'm fairly confident he wasn't carrying exit speed and could add another few miles an hour.
Bottom line, if his engine is capable of these straightline speeds, I can't imagine the additional power against Prefix's standard "head and cam" package (I'm running) adds. It's gotta be my next upgrade one day...

[Racingswh]

I met a gentleman at Sebring a couple weeks ago (when I ran my PB (personal best), "Drexler" diff thread). I can't recall his name. He was running in a different group, but had the 9 liter extreme. Great story how he bought his Viper while at Prefix and upgraded to the bigger motor.
He was running 2:17's against my 2:11 (pb), but he was hitting 160 mph against my 150 mph on the back straight. That is a REMARKABLE difference in straighline speed AND I'm fairly confident he wasn't carrying exit speed and could add another few miles an hour.
Bottom line, if his engine is capable of these straightline speeds, I can't imagine the additional power against Prefix's standard "head and cam" package (I'm running) adds. It's gotta be my next upgrade one day...

Sounds like you got yours sorted. 2:11 is ripping. Nice lap!!

Only have heard great things about Prefix. They made a mistake on a friends complete build, owned up to it immediately, and made it right no questions asked. Since he has had the engine back in the car there have been no further issues and it screams. I love the way they sound as well!!

[Arizona Vipers]

I met a gentleman at Sebring a couple weeks ago (when I ran my PB (personal best), "Drexler" diff thread). I can't recall his name. He was running in a different group, but had the 9 liter extreme. Great story how he bought his Viper while at Prefix and upgraded to the bigger motor.
He was running 2:17's against my 2:11 (pb), but he was hitting 160 mph against my 150 mph on the back straight. That is a REMARKABLE difference in straighline speed AND I'm fairly confident he wasn't carrying exit speed and could add another few miles an hour.
Bottom line, if his engine is capable of these straightline speeds, I can't imagine the additional power against Prefix's standard "head and cam" package (I'm running) adds. It's gotta be my next upgrade one day...

I think I'm gonna try that diff dude!!

[est8esq]

I met a gentleman at Sebring a couple weeks ago (when I ran my PB (personal best), "Drexler" diff thread). I can't recall his name. He was running in a different group, but had the 9 liter extreme. Great story how he bought his Viper while at Prefix and upgraded to the bigger motor.
He was running 2:17's against my 2:11 (pb), but he was hitting 160 mph against my 150 mph on the back straight. That is a REMARKABLE difference in straighline speed AND I'm fairly confident he wasn't carrying exit speed and could add another few miles an hour.
Bottom line, if his engine is capable of these straightline speeds, I can't imagine the additional power against Prefix's standard "head and cam" package (I'm running) adds. It's gotta be my next upgrade one day...

I feel I owe everyone an apology. I was so focused on the diff/LSD, I forgot my 5th gear wasn't stock and added an extra 2-3 mph top end. I was able to hit 152-153 on Sebring's back straight. Please, allow me to explain...

My original transmission needed to be rebuilt. Since Merritt (car 899) went to his sequential, I threw his car in mine. His 5th gear is different than OEM and it added an extra few mph top end. IMO, it still isn't the game changer. Only touched 5th gear on front straight and obviously back straight. Guess I need to post my actual video? Let me work on it...

[Whitey]

How many track miles do you think you have on the engine?

I have one of the first Prefix 9LX conversions. I have almost 5,000 street miles on mine. Red button works every time. Call Scot @ Prefix with your goals. He can create a great solution for you.