Better top end or bigger head unit
Thread Starter
Joined: Jun 2005
Posts: 2,265
Likes: 671
From: Oskaloosa, Iowa
I don't get the flow argument...
You don't need more flow. More boost will up the density of the air the engine is already consuming. You don't need more air flow if you can up the density 2-4x with boost alone. Sure both is a great answer and all...if time/money aren't a concern! But you will ultimately be limited by the factory block/crank at power levels a larger blower alone could get you. Why spend twice the money to get to the same point at less boost? YOU're on E85... Use that and dump tons of boost into what you have. Otherwise you're doing twice the work and spending twice the money to hit the same goal IMO.
You don't need more flow. More boost will up the density of the air the engine is already consuming. You don't need more air flow if you can up the density 2-4x with boost alone. Sure both is a great answer and all...if time/money aren't a concern! But you will ultimately be limited by the factory block/crank at power levels a larger blower alone could get you. Why spend twice the money to get to the same point at less boost? YOU're on E85... Use that and dump tons of boost into what you have. Otherwise you're doing twice the work and spending twice the money to hit the same goal IMO.
I don't get the flow argument...
You don't need more flow. More boost will up the density of the air the engine is already consuming. You don't need more air flow if you can up the density 2-4x with boost alone. Sure both is a great answer and all...if time/money aren't a concern! But you will ultimately be limited by the factory block/crank at power levels a larger blower alone could get you. Why spend twice the money to get to the same point at less boost? YOU're on E85... Use that and dump tons of boost into what you have. Otherwise you're doing twice the work and spending twice the money to hit the same goal IMO.
You don't need more flow. More boost will up the density of the air the engine is already consuming. You don't need more air flow if you can up the density 2-4x with boost alone. Sure both is a great answer and all...if time/money aren't a concern! But you will ultimately be limited by the factory block/crank at power levels a larger blower alone could get you. Why spend twice the money to get to the same point at less boost? YOU're on E85... Use that and dump tons of boost into what you have. Otherwise you're doing twice the work and spending twice the money to hit the same goal IMO.
But if the blowers almost tapped RPM wise now at 14lbs Whats the point? Wouldn't' he still be blower limited? Heads intake and TB wont' be cheap? Also wouldn't you want a cam to match the new top end? I'd still go with a power adder upgrade personally. Perhaps a non-belt driven one for that price tag... but i won't go there! 
Thread Starter
Joined: Jun 2005
Posts: 2,265
Likes: 671
From: Oskaloosa, Iowa
An F1a-94 head unit can be had new for a little over 3g. Then I could probably get a decent price out of my low mileage D1x to offset at least a 1/3 of that considering it is the newest model and a nice upgrade of a D1sc. Looking at heads if going that route I'd do aftermarket castings so TSP seems to have the most budget option there which is near $1800. Then of course new gaskets, possibly new pushrods, and intake/throttle body combos are usually over $1000. Then possibly build or modify my intake pipe from the procharger kit to fit the new intake/throttle body. Meanwhile an F1a-94 is a direct bolt in for me with the exception of the intake side of the blower being larger. So I would just ditch the crappy 180 degree turn procharger intake and put a blower guard on it.
...and like was mentioned make more than the short block can likely handle. Most think an LS3 aluminum block is safe to 1000 rwhp, but not much more long term.
I would like to emphasize that my current combo has completely lived up to my expectations. Actually beyond my expectations. Initially when the tune was getting close on the street it was the most power of I've personally owned in a true street car. After a couple months playing with it and getting better suspension/tires under it I'm interested in pushing forward on the power levels. The head unit seems to be the easiest and similar in cost if not cheaper than a new top end. I wouldn't even have to push the F1a-94 to make more than I am now so it would leave room to grow if I decide to stay procharger down the road with a better motor.
...and like was mentioned make more than the short block can likely handle. Most think an LS3 aluminum block is safe to 1000 rwhp, but not much more long term.
I would like to emphasize that my current combo has completely lived up to my expectations. Actually beyond my expectations. Initially when the tune was getting close on the street it was the most power of I've personally owned in a true street car. After a couple months playing with it and getting better suspension/tires under it I'm interested in pushing forward on the power levels. The head unit seems to be the easiest and similar in cost if not cheaper than a new top end. I wouldn't even have to push the F1a-94 to make more than I am now so it would leave room to grow if I decide to stay procharger down the road with a better motor.
I agree. The cost VS performance of HCI with forced induction just isn't there for the AVG street/strip weekend warrior. Sure in a perfect world It'd be nice to have it all... but if you can meet your goals and more with 1... why bother?
While the 180* intake isn't ideal, I wonder if you'd be better off with something like that over sucking hot air directly from the engine bay? Blower guards are great for keeping rocks out of your compressor... but little else IMO. I'd never run a "screen" on the street. TONS of dirt and crap end up in the motor and inside your blower unit. They sure don't make getting cooler ambient air to those units easy, I realize! But not starting out with 180* engine bay air goes a long way in terms of charge cooling and IC efficiency. Can relocate that overflow tank and put a large hole in the fender well behind the shock tower and snake a filter in there?
While the 180* intake isn't ideal, I wonder if you'd be better off with something like that over sucking hot air directly from the engine bay? Blower guards are great for keeping rocks out of your compressor... but little else IMO. I'd never run a "screen" on the street. TONS of dirt and crap end up in the motor and inside your blower unit. They sure don't make getting cooler ambient air to those units easy, I realize! But not starting out with 180* engine bay air goes a long way in terms of charge cooling and IC efficiency. Can relocate that overflow tank and put a large hole in the fender well behind the shock tower and snake a filter in there?
Is your rad stood up already? If not you will have to consider that or atleast moving it forward. I know of three cars that have had to stand up or move the rad more forward to fit the -94 in the stock Fbody location. There are actually a few threads on here stating the same from people. I tried to put one on my car that I borrowed and it was hitting the fan shroud/rad with no inlet protection at all.
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Verdad Gallardo Thread Starter
Joined: Jun 2005
Posts: 2,265
Likes: 671
From: Oskaloosa, Iowa
Is your rad stood up already? If not you will have to consider that or atleast moving it forward. I know of three cars that have had to stand up or move the rad more forward to fit the -94 in the stock Fbody location. There are actually a few threads on here stating the same from people. I tried to put one on my car that I borrowed and it was hitting the fan shroud/rad with no inlet protection at all.
Thread Starter
Joined: Jun 2005
Posts: 2,265
Likes: 671
From: Oskaloosa, Iowa
On a side note got to love Iowa for the cheap
race gas. $1.50 a gallon 5 minutes from home.
I actually always get it in a jug and test them dilute with 93 because I don’t have enough injector for 95 percent. It’s always over 90 though so I know it’s there when I can run it.
Running ethanol of some form in all my toys. I've run as high as E98 and saw no gains over E70 at the track in the RX7. So E70 is all I run in it now. "E85" Pumps are at a steady 70% at the sketchy "Petro America" station year round. Lower blends also seems to gum injectors less. E50-60 has zero issues with the "Ethanol goo" in my experience and also seems to provide all the knock suppression I need to run 20lbs on a non intercooled twin turbo 5.3 mustang. (that's with whatever crap blend fuel they use) I'd bet that E95 you got there mixed with ethanol free 91-93 octane at 50% eth. would be MORE Than enough fuel/octane for anything you'll throw at it with that blower. (or the new one)
I do use E98 on my air-cooled minibike! lol... seems to run cooler. Have to drain the carb after every use and plug the tank/carb vents or I get GEL/GOO in the carb. fast. Guess I'm just saying higher blends can be a pain and I don't see the benefit, at my power levels anyway...
I do use E98 on my air-cooled minibike! lol... seems to run cooler. Have to drain the carb after every use and plug the tank/carb vents or I get GEL/GOO in the carb. fast. Guess I'm just saying higher blends can be a pain and I don't see the benefit, at my power levels anyway...
Thread Starter
Joined: Jun 2005
Posts: 2,265
Likes: 671
From: Oskaloosa, Iowa
Running ethanol of some form in all my toys. I've run as high as E98 and saw no gains over E70 at the track in the RX7. So E70 is all I run in it now. "E85" Pumps are at a steady 70% at the sketchy "Petro America" station year round. Lower blends also seems to gum injectors less. E50-60 has zero issues with the "Ethanol goo" in my experience and also seems to provide all the knock suppression I need to run 20lbs on a non intercooled twin turbo 5.3 mustang. (that's with whatever crap blend fuel they use) I'd bet that E95 you got there mixed with ethanol free 91-93 octane at 50% eth. would be MORE Than enough fuel/octane for anything you'll throw at it with that blower. (or the new one)
I do use E98 on my air-cooled minibike! lol... seems to run cooler. Have to drain the carb after every use and plug the tank/carb vents or I get GEL/GOO in the carb. fast. Guess I'm just saying higher blends can be a pain and I don't see the benefit, at my power levels anyway...
I do use E98 on my air-cooled minibike! lol... seems to run cooler. Have to drain the carb after every use and plug the tank/carb vents or I get GEL/GOO in the carb. fast. Guess I'm just saying higher blends can be a pain and I don't see the benefit, at my power levels anyway...
I still like the higher alcohol content from the pump so I can dilute it with 93 instead of the 87 they use.
TECH Fanatic
Joined: Dec 2017
Posts: 1,611
Likes: 1,086
I have a question..
If you pulley down to spin the blower at MAX rpm, then decide to do a better top end. This would likely cause a drop in your overall boost peak psi. Now, would the blower RPM also decrease or stay the same? If it stays the same, then you're still capped with that blower regardless of what you do. So, you wouldn't be able to pulley down even further to recoup some that boost pressure you lost, to gain even more power from the new top end you installed.
I don't know much about centris. Mainly just curious how it works.
If you pulley down to spin the blower at MAX rpm, then decide to do a better top end. This would likely cause a drop in your overall boost peak psi. Now, would the blower RPM also decrease or stay the same? If it stays the same, then you're still capped with that blower regardless of what you do. So, you wouldn't be able to pulley down even further to recoup some that boost pressure you lost, to gain even more power from the new top end you installed.
I don't know much about centris. Mainly just curious how it works.
Thread Starter
Joined: Jun 2005
Posts: 2,265
Likes: 671
From: Oskaloosa, Iowa
Blower rpm for reference is: Crank pulley diameter divided by blower pulley diameter times step up ratio times engine rpm. It's not uncommon for people to spin the blowers faster than the recommended rpm either.
Thread Starter
Joined: Jun 2005
Posts: 2,265
Likes: 671
From: Oskaloosa, Iowa
I had the head unit off to change the oil and decided to bump it up a hair by changing the pulley from the 3.9 to the 3.85. Not much of a change and barely needed any adjustment to the VE table to get fueling where I wanted it. I've got it running 11.3 to 11.5 on the gas scale, but dropping down to 10.9 once it reaches 14 lbs. I'm on a 2 bar map and richen that last couple rows of the VE table a little bit in case it maxes out my 2 bar. It's in the 90's now so I suspect in cooler weather it will max out the map sensor.
Looks like I might actually get to run the car this friday in the 1/8th mile, but of course it's suppose to be well into the 90's. I never got to run the car at the track in cooler weather due to world issues and weather.
Looks like I might actually get to run the car this friday in the 1/8th mile, but of course it's suppose to be well into the 90's. I never got to run the car at the track in cooler weather due to world issues and weather.
I have a 94 in my 06 GTO and I had to massage the fenderwell because of the bigger intake diameter. Also, I ended up using a 60 degree elbow for the intake pipe in order to get a big enough air filter in between the coil packs and computer area (you would and should relocate your coolant tank). I generally run 15 degrees over ambient sucking in the hot air and passing it through a treadstone IC.