high altitude boost

Krace

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Ok, I have a tricky question here.

I drive a 2012 5.0 and I want to get a supercharger for it, but I want to get to the 600rwhp mark. I see this number a lot at sea level on the stock motor with a Vortech and some bolt on's.

Now I understand that up here (6500ft) we make less power and need to run more boost to make the same power at sea level.

The question I have is, can I just run the psi up to the point to 600rwhp uncorrected (or close to it ~570+)? Or can the motor not take the pressure of the boost? I'm thinking in the 13-14 psi up here will get me there, but idk.:??:

Any info will help!

Haha and WOOO! FIRST POST! im a long time reader +3 years!
 

slagburn

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Man, we really need to set up a CO subforum or something. There are quite a few people up here that just can't live with the reduced power from elevation and go with blowers and turbos. Haven't seen nitrous up here yet for what it's worth.

It takes a lot of boost up here to get to 600 uncorrected, especially with the extra elevation in COS. A built motor is never a bad idea and keeping the stock CR of 11:1 is the way to go if you end up going that route.
 

92hatchlx

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I made 500/400 uncorrected (600/480 SAE corrected) when I dyno'd in Aurora. I was pushing 6 PSI out of the stock paxton kit with ID1000 injectors and a lund tune. Weather was decent. What type of supercharger are you looking to get?
 

Krace

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Man, we really need to set up a CO subforum or something. There are quite a few people up here that just can't live with the reduced power from elevation and go with blowers and turbos. Haven't seen nitrous up here yet for what it's worth.

It takes a lot of boost up here to get to 600 uncorrected, especially with the extra elevation in COS. A built motor is never a bad idea and keeping the stock CR of 11:1 is the way to go if you end up going that route.

Haha....

Yea I was thinking of doing nitrous, but I just dont want to refill that damn bottle all the time. :p

I made 500/400 uncorrected (600/480 SAE corrected) when I dyno'd in Aurora. I was pushing 6 PSI out of the stock paxton kit with ID1000 injectors and a lund tune. Weather was decent. What type of supercharger are you looking to get?

I was looking into a Vortech kit, more or less its the same as the Paxton. I just like the look of the black blower better. :coolman:
 

92hatchlx

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From what i have taken in, you will probably be spinning that head unit at its max efficiency trying to make 600 uncorrected in the Springs. I would say go for it if you aren't looking to make anymore than that. If you want a little more expandability, I would go for the 2200SL or opt for a different head unit with the Vortech kit. You will be happy with whatever you choose. The polished finish looks great under the hood also.
 

Krace

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From what i have taken in, you will probably be spinning that head unit at its max efficiency trying to make 600 uncorrected in the Springs. I would say go for it if you aren't looking to make anymore than that. If you want a little more expandability, I would go for the 2200SL or opt for a different head unit with the Vortech kit. You will be happy with whatever you choose. The polished finish looks great under the hood also.

Yeah i dont want to push the motor more then the 600 mark... even at the 560rwhp~ range id be happy.
 

tt335ci03cobra

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Because of load and parasistic drag I'd be really careful about pushing for 600whp uncorrected at 6500 ft. That's about a 16% oxygen loss meaning harsh conditions.

By the time you run enough boost to turn out 600whp, the motor will have been developing som 950hp because of parasistic drag. 13psi on a mod coyote with vvt-ti has made 1000whp in turbo trim...

All that internalized stress on the motor will necessitate a built short block to last.

Honestly, I'd spend a little more and have a reputable shop make a custom single 76mm kit for ya, a turbo will simply spin a little faster to compensate for altitude. It does this because the boost settings are mapped to oxygen count instead of air flow so you'll end up flowing 11.6psi of high altitude air but it really only equates to 10 psi of sea level air when the oxygen count is measured. If the turbo wheel was spinning at 57,000 rpms at sea level, it'll spin to about 16% faster speed so about 65,500 rpms. The air is thinner so it's not actually stressing the motor as the volume is 16% thinner per square inch of density.

In short, superchargers at altitude equate to lots of stress because each pound of boost is 16% less efficient from the get go and the only way to up boost is more parasistic drag.

With turbos, the wheel will naturally spin to a match preset oxygen counts and is spinning thinner air so it doesn't experience the resistance that a blowers lobes/and or belt drive must experience as they aren't spun simply by air alone.

I'm at 4600ft and almost went with a wastegated procharged f1r on my 5.4 build but decided to go turbo especially because of the altitude and the ability to adjust boost via an in car electronic boost controller.

It's more expensive than a procharged but done right, turbo(s) are soooooooo cool at altitude.

If you have any questions please ask! Good luck man
 
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Krace

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Because of load and parasistic drag I'd be really careful about pushing for 600whp uncorrected at 6500 ft. That's about a 16% oxygen loss meaning harsh conditions.

By the time you run enough boost to turn out 600whp, the motor will have been developing som 950hp because of parasistic drag. 13psi on a mod coyote with vvt-ti has made 1000whp in turbo trim...

All that internalized stress on the motor will necessitate a built short block to last.

Honestly, I'd spend a little more and have a reputable shop make a custom single 76mm kit for ya, a turbo will simply spin a little faster to compensate for altitude. It does this because the boost settings are mapped to oxygen count instead of air flow so you'll end up flowing 11.6psi of high altitude air but it really only equates to 10 psi of sea level air when the oxygen count is measured. If the turbo wheel was spinning at 57,000 rpms at sea level, it'll spin to about 16% faster speed so about 65,500 rpms. The air is thinner so it's not actually stressing the motor as the volume is 16% thinner per square inch of density.

In short, superchargers at altitude equate to lots of stress because each pound of boost is 16% less efficient from the get go and the only way to up boost is more parasistic drag.

With turbos, the wheel will naturally spin to a match preset oxygen counts and is spinning thinner air so it doesn't experience the resistance that a blowers lobes/and or belt drive must experience as they aren't spun simply by air alone.

I'm at 4600ft and almost went with a wastegated procharged f1r on my 5.4 build but decided to go turbo especially because of the altitude and the ability to adjust boost via an in car electronic boost controller.

It's more expensive than a procharged but done right, turbo(s) are soooooooo cool at altitude.

If you have any questions please ask! Good luck man

Wow ty for the info ... i will think about what you have said.... just sucks up here.
I love being N/A but im lucky if i hit the 350whp with my mods (3.73, boss manifold, L&M 82mm tb, JLT CAI, UPR off road X pipe, pype's axle backs Bama 91R tune) I was thinking of getting 47lb injectors, and getting a airaid CAI then get a e85 tune from Shaun@AED (Shaun advised me to ditch the JLT and get a steeda or a Airaid to better to tune with). But that may get me to 370ish... so yeah with all that ill feel like im stock at sea level, yay!
 
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slagburn

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Wow ty for the info ... i will think about what you have said.... just sucks up here.

Yep, when I first put the 2.3 Whipple on my car it was making about 560 corrected. Took a few friends for a ride in the Springs on a warm day, it wouldn't even spin the tires in first gear with their extra weight. :whine:
 

truebluedevil02

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Welcome. Hope you can make it up to meet Slagburn and myself one day. Up here you need 750SAE whp to get a true 600whp here. I don't think the vortech kit will do it, and if it does, it will be maxed out. I'm going with the paxton and will be painting it black as I love the blacked out look as well. Look into going E85, that will help A TON. Also, if you go with a paxton or vortech this fall, send me a PM, since I'll be doing the same(in February) I would like to see how it all goes on and the trimming required on the bumper.
 

sambandit

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Welcome to the site, lots of good info here. 750ish RWHP corrected is the mark you are going to have to look at in order to be somewhere around 600 uncorrected RWHP. I believe when I was at 670 corrected, that was 540 uncorrected or so.

Make sure you get a big enough blower that you can spin hard enough to obtain your goals. I think small ones like a P1 Procharger or something like that probably wont cut the mustard. Don't know how the Vortech compares in size, IE is the 2200 similar to a D1 or is that their entry level blower?
 

Bud

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Because of load and parasistic drag I'd be really careful about pushing for 600whp uncorrected at 6500 ft. That's about a 16% oxygen loss meaning harsh conditions.

Good info I think gets over looked. To get to 600whp uncorrected up here we have to spin a blower much faster or spin a bigger blower which puts more parasitic load on the motor than it would take to get to the same wheel horsepower at sea level.

Have to go with a big blower up here if you want to get things done with just a blower and no other mods. What gets sea level people 9's gets us high 10's to low 11's up here. I suggest getting the biggest blower that fits reasonably well, eventually you will need it here.

Good to see another Colorado person looking to have fun with their car up here. Good group of people already running different superchargers up here at altitude so should be able to get some ideas on what is possible before jumping in.
 
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calgarybandit

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Usually in Alberta we are 4000 - 5300 DA I am thinking hard this winter of pulling the block and putting in a Procharger F1C.:banana:
 

truebluedevil02

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V-3 Si Supercharger | Vortech Superchargers
This is the blower that is in the kit. Its not to bad, looks like you can run it up really well.

But Im also looking in to a turbo set up.... Hellion Single Turbo Kit - Tuner Kit (11-12 GT) - Free Shipping!

I may just do my own fuel system, so I run it with e85. But I also will like to be able to run it with 91 as well.

Do some research about the hellion single kit. A lot of people say its has a lot of problems with surging, valve float, boost leakes, etc. It seems these cars like twin much better than single's. The Vortech craps out at about 700-750whp(youll max it out to make 600whp up here) Thats why you should consider the 2200sl(good for over 1000whp in the base paxton kit). I like the black vortech kit as well but Ill simply mask and paint the paxton and get the same result. Also, the paxton is a few hundred $ cheaper than the base vortech kit. PM Beekcake, he is a very well known vendor on this site is is happy to answer any questions you will have. He also Daily drives a 1000whp coyote with a paxton kit on it and he will cut you a stupid good deal on parts. Like stated above, you need a big blower up here, a pulley that gives you 10psi at sea level will get you more like 7 psi up here so you have to really pulley down the blowers to get boost out of them.

Another thing. Slagburn just made 810whp on the stock pump, an 18V BAP and ID1000 injectors. Because we lose so much power up here you can hit really close to if not a little over 600whp HERE on slagburns basic set up on E85.
 

tt335ci03cobra

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Ya I would be weary of the hellion single. I think a reputable custom kit or large blower on 12psi for longevity sake.

I would look into a custom single before deciding on a large centri though just to way the cost and options. Fuel mods would be similar either way so actual build costs of a custom single could be on par or possibly less than a fully optioned Paxton or other centri blower.


With a custom single, cost can be relatively minimized vs twins, you can place the battery in the trunk to balance weight and put the single in its place in the engine bay for placement, and vvt-ti does an excellent job of spooling even a large single really well. A single 76 with an 80mm wheel should make 900-1000whp on 14psi and probably be marginally less stressful on the motor vs a large blower like a Paxton at 14psi making 700whp. The other thing to remember is that apart from avoiding parasistic drag, turbos pull and push the pistons and rotating assembly in a very harmonically balanced motion. All blowers regardless of design and efficiency can only push the on the valves and pistons which is more stressful. The force on both sides to generate the same power and rotational speeds is much softer as it spreads force about 60/400 push/pull vs 100% pushing force. It's not an even 50/50 for many reasons. I won't bore with all the details.

1100 crank hp from a turbo mill is softer, less stressful power than 1100 from a big blower. Couple that with the relative reality that even a big blower will struggle to show 700whp uncorrected even on say 14psi up at 6500ft and that a well done custom single coyote will put out 900-1000whp at 14psi and the plot thickens.

Other thing to think about is lag. A large centrifugal is more efficient than a large pd blower on top end, but it will have an even smaller effect on low and mid range torque/power than a traditionally well matched centrifugal as the extra air flow potential requires more spin to maximize. A well fitted single turbo would offer worlds of mid and low range torque as well as a very plateaued peak power.

A well built centrifugal motor will show a power graph similar to this (not numbers but actual curve of it):

3e2y4epu.jpg


While a rightly done custom single can easily show a graph like this:

9asypapy.jpg


(my own pulls uncorrected on 20psi, long spool because it was an unloaded pull as we didnt want to over stress on baseline tuning, we pulled timing up top to test a higher rpm run, made more after but I don't share those numbers to keep a few tricks up my sleeve)

The average power you'll have even at say 6psi with a single would feel 1-250whp/tq stronger from 2500-5500rpms than a traditional centrifugal making the same power of about 600whp uncorrected. A centri will touch 600whp near redline, but a single turbo will hit it from about 5000 to 7000 rpms. Below the power curve (Or power plateau in a turbo mill), average power once spooled is intense as its running an unrestricted, non dragged, and fully spooled 6psi from say 2500rpms until redline. You'll literally be some 250wtq higher with a single turbo from 2500-4500rpms vs a centri. At 6500ft, you'll be able to be in 4th gear around 3500rpms and murder c6z06's from a roll like they are in a truck. I think c6z's make 360whp uncorrected up there. You'll about average 600whp the entire rev range with a properly done turbo set up while a centri will average about 530whp through the same span as it goes from about 480whp at 5000rpms to 600whp at 7000rpms.

Track times should be about a second faster if you can hook and trap speeds should be 5-6mph faster turbo vs. centri if you can get the curve to plateau.

To launch with boost, a $200 wide open throttle box with a 2-step is all you'll need. You'd be able to shift wide open throttle (no lift) for upto .500 seconds and it's adjustable down to .200 seconds as the box tells the ecu to hold timing momentarily. The 2-step lets the turbo spool up to about 60% of any available boost during loaded real world runs at a given rpm. Launching it is easy once set up. Clutch in, put it in 1st, flat foot the gas pedal, and it'll hold the rpm you set it for. I use mine around 3000rpms with 6psi of boost. I have 28" tires, a 3.08 rear and 2.66 first that can hit 70mph at 7000rpms. If I launch any higher I spin so it's very easy to get a Turbo manual car to launch hard even with tall gearing, contrary to popular opinion.

Good luck, and look around for a good shop if a single interests you at all, I would really consider it given your goals/hurdles.
 

92hatchlx

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I'm not sure of anyone that could build a complete, reliable and reputable single kit for less than $5400 including injectors, tune, and dyno time. Unless you have the skills to do it on your own.

My choice was made very easily after going back and forth on a PD, turbo or Centri. It was cheaper, still makes great power, head unit and intercooler are good up to 1000+ horsepower (I highly doubt I will ever max out this head unit). Aside from the fact that if you do it yourself, your car will only be down for one day.

The turbo route would be great if I wanted to spend that much money on a kit and if I had extra time to spare to install it. Decide which is best for you. Any route you go, you will be impressed.
 

truebluedevil02

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I'm not sure of anyone that could build a complete, reliable and reputable single kit for less than $5400 including injectors, tune, and dyno time. Unless you have the skills to do it on your own.

My choice was made very easily after going back and forth on a PD, turbo or Centri. It was cheaper, still makes great power, head unit and intercooler are good up to 1000+ horsepower (I highly doubt I will ever max out this head unit). Aside from the fact that if you do it yourself, your car will only be down for one day.

The turbo route would be great if I wanted to spend that much money on a kit and if I had extra time to spare to install it. Decide which is best for you. Any route you go, you will be impressed.

Thats it. You can get the Paxton tuner kit for under $4300 if you know where to look:-D. No way you can build a high quality turbo kit for that with top shelf parts unless you do it yourself.
 

tt335ci03cobra

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4300 plus labor though, and tuning though. 5000+ out the door with dyno tuning. Also what costs more? $1,000 upfront, or $10k a year later for a blown motor?

If $500-1,000 makes or breaks a build I'd do neither, if/when the motor lets go you'll be unable to build/replace broken parts if 1,000 makes/breaks the budget. Also if it's your daily driver, you'll need to pick up a beater either way unless you can overcome possibly being stranded with a broken car via borrowing a car..

Save up and be ready to build a short block if you go sc, the mottor will be very stressed and 15,000 miles will probably pop it at those stress levels. If you were at sea level, you'd probably be good for 50,000 miles at 600whp but thats because the motor will only be making about 800hp. To get 600whp at 6500ft, the motor will be stressed to about 1000hp. Coyotes are awesome but they are still machines, they aren't invincible.

Anyways it's not that centris are bad, but for 600whp at 6500ft, it's a quick, easy install/setup but its a quick fix that'll cause a lot of grief long term.

I tried a quick fix by putting a 150 shot on my pullied eaton up here at 4500 ft back in 2007 because at the time I couldn't afford $1500 more for a lightly used whipple, it was awesome for 10,000 miles, then it blew. High altitude isn't like sea level, stress is harder because of detonation risk with the low o2 counts. Couple that with excessive drag do to thin air and high pulley ratios, and you get a recipe for metal fragments.

I'm just offering real world advice, everything looks great on paper and planning, but just because a coyote can hold 1000hp at sea level, don't expect it can do so in every application, specifically at high altitude, with thin air and tons of parasistic drag. That's 1000hp the really really hard way, it won't last long vs soft easy power without parasistic drag.

if price is the issue, wait either way because a blown motor is more expensive than both power adders combined. That's not happy or uplifting info but I'd rather tell ya the upfront honest truth than a glorified idea that can't really last well at 6500ft.

:-/
 

truebluedevil02

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I think you have it backwards. The motor at 600hp up here is only stressed to 600hp, not 750-800. There are several(slagburn/sambandit) and a few others that were making close to 600whp here for a lot of miles. That is was PB blowers that are much harder on the stock internals than a turbo/centri.

OP, dont worry about the motor. It can/will/has handled everything have thrown at it up here. Slagburn had a bent rod(very slight bend), but also had over 28K miles on the blower setup and a lot of runs. Like I said, that was with a PD blower, a centri is much easier on the internals of the motor. I DD my car and have no reservations about running 550-600whp here so 700-750whp SAE. It will handle it just fine.
 

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