jobe_ls1

iTrader: (9)

Recently I have been thinking about going from my current F1A procharger setup in a C5 to a new front feed whipple 2.9 setup. I'm not too up to date with the companies that make parts for custom kits but the whipple would definitely be a custom setup and not a kit. The main reason I am considering this is because I want a better street/road course car with flat torque vs the peak power. My torque curve goes from 400ft-lbs at 2500rpm to 720ft-lbs at 5000 rpm and so it's hard to control the throttle to keep traction pulling through the rpms. I could control this some with a cam change but would not get nearly the low end torque and flat curve.

So my questions are like what kind of power can the 2.9 do while keeping reasonable iats and constant? My f1a flows 1575 cfm which is good to about 1100 chp and the 2.9 maxes at 1700 cfm or so meaning it has 1300 hp in it?

My goal would be keeping my same hp and torque so 800 ish rwhp and 700ish ft-lbs. I spoke to whipple and they said this might be pushing it and should probably check with a few builders that have done and run this setup.

My current setup is a built 427lsx with TEA 245 6 bolt heads. This would require the cathedral manifold that will probably then need to be ported. I also need an 8 rib tensioner and bracket with the vette offset but not sure if this exists.

Any help or experience you can provide would be appreciated.

CBM Motorsports

iTrader: (2)

I would say that 800whp with that blower is going to be pushing it. The CTS-V guys are getting to 700whp but thats on a 6.2 liter. Your 427 is going to make that blower spin even faster to make the same boost. I can see very high IATs in the future. A 3.3 would get you there but you would have to notch your cowl and get a big hood. If you go that route, you might as well go to the 4.5!

dw456post

Call Magnuson about their setups. 8 rib are available.

jobe_ls1

iTrader: (9)

Whipple actually mentioned you to get more info. That's what I was thinking. But I did see a caddy on here that put down 850rwhp. Not sure what the iat was and if it keeps climbing or flattens out. Not worried about the hood but notching the cowl might be a deal breaker.

I know whipple makes 8 rib setups but are they for the vette offset?

Murder_C5

Maybe look into adding a wastegate & E-Boost controller to control boost & power curve.It will be alot cheaper & easier/faster than swapping S/Cs'. There are some good articles about wastegates on centri set-ups making more HP&TQ under the curve.
Im probably going to go to a smaller pulley & ad a wastegate & E-boost controller.
Check out, http://www.gmhightechperformance.com...ate/index.html
Search "centrifugal supercharger wastegate" for more input on the subject.

chuntington101

go 4.5 or go home!

You could look at side mounting the blower. Dragon racing used to do them and i think are coming out with a revised version.

what the c5 and 6 guys really need is whipple or CBM to come up with a front drive / front feed setup.

CBM Motorsports

iTrader: (2)

We are currently designing a box that bolts on the back of the 4.5 to bring the throttle body around to the side of blower facing forward. We already make them for the 3.3 and 4.0. We actually make them for Whipple as an optional part. A front feed 4.5 would be awesome and would be a lot easier to make fit on Corvettes and Camaros. I will see what I can do.

As far as beltlines go, we can do a 8 rib on the Corvette beltline. It is a simple snout change and Whipple makes every length you can think of. For as much power as you would like to make, I would suggest a stand alone 10 rib for the blower.

jobe_ls1

iTrader: (9)

Actually no thats not crazy. I have heard of some buddies toying with that idea. My idea is a somewhat reversed from gmht article in that I would keep my same blower speed and bleed lower gears boost. So if I could find a boost controller that uses gear position, that would be epic! And if it had rpm input as well that would be a neat feature. So you know a manufacturer for one of these?

jobe_ls1

iTrader: (9)

I found this steve morris setup in engine labs http://www.enginelabs.com/news/video...street-action/ and it is very close to what I was thinking. There is also a ctsv thread in the forced induction section that puts down 850rwhp but im not sure if that was assisted with spray. I know he had it but not sure if it was used.

I have a flip drive so its already stand alone and the blower is driven off a 8rib 8" vette IW balancer. I would only need 4 8 rib pulleys. Two idlers, tensioner and jackshaft. And maybe a ls3 waterpump. Have a pic of a ls2 water pump bracket?

If you make a front feed for anything bigger than a 2.9 please let us know, i would be all over that.

Bob@BruteSpeed

iTrader: (16)

Have you considered swapping your F-1A for an F-1D? It might just get you the added low end power you're looking for. Bob

chuntington101

How much longer is the 4.0/4.5 than the 2.9? I was thinking if they are significantly longer then they are going to be hanging quite far off the front of the motor! Also are they enough spare fixtures on the blower / manifold to attach a drive shaft like Maggy uses? That was you could just use belts that might be easier than the whipple (geared?) setup.

Or you could go for a hydraulic drive unit!

Or even dafter, how about a rear mounted SC that takes its drive off the drive shaft (corvette only obviously)? It's should be the same speed as the engine and should take some of the shock loadings out of the SC as it would only be engaged when the clutch in out. Lol

Murder_C5

Maybe look into a Turbosmart e-Boost (#TS-0301-1002) it's pretty nice/advanced.The gear based mapping would be something to look into
It features:
- Boost Levels: up to 6 levels of boost.
- Boost on Demand: provides instant overtaking power
- Gear-based Mapping: set a different boost for each gear!
- Adjustable Boost Levels: program boost against TIME or RPM.
- Aux Output: fully programmable; controls water spray, methanol or nitrous injection.
- RPM Compensation
- Peak Hold/Max Boost Recall: monitors boost and RPM.
- Gate Pressure: eliminates wastegate creep.
- Overboost Shutdown: provides added protection for your engine .
-Display: programmable, can be configured to KPA, Bar or PSI.
- Auto Dimming: with backlit buttons

OR the HKS EVC-6
It has alot of the same features but more expensive.
-High Boost Capability * 250kPa/36PSI
-Target Boost * User inputs target boost level, and the EVC automatically adjusts pressure to reach desired level.
-Offset Function * If boost exceeds or does not achieve user’s target, boost pressure can be offset to reach desired level.
-Map Correction Mode * Boost pressure can be fine tuned for: Throttle Position, RPM, Vehicle Speed, Throttle Position + RPM, or Throttle Position + Vehicle Speed.
-Dual Boost Mode Settings * Separate A and B boost levels can be input independently from each other, and selected depending on driving conditions.
-Scramble Boost Function * When the scramble boost trigger is depressed a preset boost increase will occur for a predetermined time (0-60seconds).External Scramble Boost Trigger compatible.
-Metric or SAE selectable monitoring * Users can choose during initial setup metric (kPa) or SAE (PSI) boost pressure measurement for monitoring.
-Warning Function with Boost Drop Feature * A user preset warning level can be set where visual and audible alerts occur if the warning level is reached. Boost pressure can be preset to drop to a user defined level if pressure reaches warning level.
-Analog and Digital Boost Monitoring * Boost pressure can be displayed in both an analog bar graph format and a digital numerical value.
-Additional Digital Monitoring * Along with Boost Pressure two additional vehicle vitals can be monitored: Throttle Position, Engine RPM or Vehicle Speed.
Selectable Analog Monitoring * The digital bar graph can be set to monitor: Boost Pressure, Throttle Position, Engine RPM or Vehicle Speed.
-After Image Function * Users can set the EVC to display the highest boost pressure reached for 3-seconds after the throttle has been released.
-Peak Hold * The EVC will store to memory and keep displayed the maximum boost achieved.
-Data Lock * To prevent accidental data changes from occurring, the EVC can be locked with a user defined four digit code.
-Positive LCD display with LED Lighting * Black foreground with white background and LED lighting provides excellent visibility during both daytime and nighttime use.
-Dimmer Function


Or the Greddy Profec E 01 (MUCH Cheaper though not as advanced as the HKS or TurboSmart , my opinion)
- Meter display features analog and digital display for boost, rpm, throttle position.
- Displays Emanage injector maps for air/fuel adjustments.
- High and low boost settings.
- Graphing function.
- EL large screen to check all the information accurately.
- High sensitive pressure sensor measures up to 300 kpa of boost.
- Compact solenoid valve allows you to install it anywhere you want.
- Boost control function can be chosen from AUTO or MANUAL mode.
- To obtain steady boost pressure, this boost controller features GAIN function.
- Start-Boost-function allows you to adjust how quickly you want that boost.
- By inputting individual boost correction on each engine rpm, you can set boost more precisely.
- Peak-Hold-function shows maximum boost in the screen, which have been recorded so far.
- Warning-function alarms you by LED and beep sound when the actual boost becomes over the set boost.
- Limiter-function decreases boost to the point you set when the actual boost becomes over the warning boost.
- Each data and program are recorded in SD card. It enables the system to be upgraded in the future.
- By using USB cable this boost controller can work with GReddy e-manage. Even if you don't have lap-top computer, you can set the data of e-manage & also save it by using the hand-set.
- All the data on the screen can be recorded and you can play-back them later. MAP-trace-function of e-manage can be recorded and played-back

The Best one out is supposed to be the AMS-1000
Just search it & go to their site for all the info/features. ams100.com VERY NICE

I personally don't know which one would be better suited for your/our application, (im planning to do the same thing). I do however have experience with HKS on past turbo cars & have no complaints whatsoever, also HKS has been around longer (I think). If you find out anything keep it posted. Stay ProCharged, no chance of cooler failure killing your engine (water leak into cylinders).

Murder_C5

Oh alot of LS racers are using the AMS-1000 so it may be better suited for the domestic apps & I havent found a bad word about it.

grocerygetter

iTrader: (2)

Leash makes some nice stuff at this level of build as well

Murder_C5

Yea the Boost Leash seems pretty nice but people say you need a Pulse-Leash/"Bump Box" & that comes to $750 + Co2 to get the best performance out of it.
With less features, not as user friendly & about the same $$$ Im thinking the AMS-1000 is the best way to go or....... for less $$$ the,

Turbosmart e-Boost has Gear-based Mapping: set a different boost for each gear & the adjustable Boost Levels: program boost against TIME or RPM.

Or HKS EVC-6 has about the same Map Correction Mode * Boost pressure can be fine tuned for: Throttle Position, RPM, Vehicle Speed, Throttle Position + RPM, or Throttle Position + Vehicle Speed

Anybody have experience with these especially the AMS-1000 ?

Exidous

iTrader: (11)

This only ideally works if the centri has a lot of RPM to spare meaning at your current power level you and not near max impeller speed. So to get the same peak power you pulley down the centri for max impeller speed and bleed off the boost to the PSI you were running before. I have toyed with the idea as well as I will be running a D1SC and NOT max impeller speed.