C Murda

iTrader: (24)

goal of 1000+RWHP. plannimg on a garret ball bearing turbo was looking at 45r up to 47r. dont know what to do about ar sizes and and compressor sizes. T4 or T6? id like to use a T4 so my downpipe can be a 4" and i can easily wrap that through my Spohn k member...just need some input form the pros...

Mike@Diablosport

iTrader: (2)

No pro here, but you will need a T6 flanged turbo to see 1000rwhp.

hellbents10

iTrader: (10)

A S91 would work nice for you, t-6 of coarse.

BlazinT/A

iTrader: (10)

im gonna throw a gt4788 out there it seems everyone who has them is making close to that kind of power minimal problems or check with forced inductions about the FI-88X or FI-91X

DrTurbo

iTrader: (3)

You will need a T6 with a 427 and 1000rwhp. Also check on the FI-91X, or FI-94X. Also if you have some $$ left, go with the EX-94X billet turbo. Awesome piece....

The GT47-88 will NOT make 1000rwhp on a 427. Probably be done around 850-900max.....back pressure will be high with it!

Pro Stock John

iTrader: (34)

A friend made 920 on a load dyno with a 408ci, race gas and a GT47-88. I would think that a GT55-91 would be a better choice if focusing on Garrett parts.

I made 867rwhp with my GT47-88 and a 348ci they can make 1300hp I think.

Shawn @ VA Speed

iTrader: (3)

we have made over 1000rwhp with an 88 on a 370,for a 427 i would go with a 91

C Murda

iTrader: (24)

do you mean it will be done as in efficiency? cause otherwise why are these rated at 1200+hp?

also are the FI-X turbos ball bearing?

Shawn @ VA Speed

iTrader: (3)

on smaller turbos you need to spin the turbo faster to make boost-the faster you spin the turbo the higher the exhaust backpressure becomes-killing power,while an 88 might make 1200hp it doesnt make it on every size engine

C Murda

iTrader: (24)

understood! so i guess im looking at the GT55R turbo. i really want it to be a ball bearing turbo which is why i guess im staying in the garret family. no would i have any problems using a 5"-4" reducer off of the turbine side so that i can use a single 4" down pipe still?
i just barely have room for 4"s so 5" would not work all the way. also what AR should my turbine housing be?

damn looking at the price of this turbo so far the cheapest brand new from a dealer price is $3700.

C Murda

iTrader: (24)

oh and another thing...how quick would spool time be with the GT55R on a 427? at what rpm would i achieve full boost?

Pro Stock John

iTrader: (34)

Stick or auto?

Shawn @ VA Speed

iTrader: (3)

a 4'' down pipe would be fine on your application-usually good to 1500hp,you could go with 1.15 ar and be fine,it would spool up faster too,spool also depends on cam selection as well an compression.I can get you that turbo way cheaper than that.

C Murda

iTrader: (24)

ya its a stick...i know it will be a beast on the street but i like a challenge. as for compression i will be shooting for 8.5:1 maybe even lower i have not decided yet as i do want to run it on pump gas to hit 800+RWHP. as for cam im gonna have to discuss it over with my tuner. car is fully built and ready for the power just need to start piecing together a turbo kit and then switch whatever i need to switch in the motor. aaaannnd im hoping that turbo will fit where up front where my battery used to be... anyone have any real time pics of a gt55R or equivalent (physical) size turbo that i can look at? maybe do the old compare it to a coke can or a nything so i can get an idea of the turbo's actual size? if i cant get that to fit in the area my battery was then i am already running into problems...

DrTurbo

iTrader: (3)

They are not ball bearing....really no need for BB on big motors.

Also HP ratings should have a big * beside them. they are based on peak efficiency.

Pro Stock John

iTrader: (34)

You can fit a big turbo up by where battery is, a few cars have done that.

800rwhp with a T56, 427ci, and a turbo on pump is doable on the dyno but at the track you should run race gas since the car will be under load for a 1/4 mile and that's different then running a dyno hard for 3 seconds.

DrTurbo

iTrader: (3)

Here are some pictures.... This is the FI-98X, but same as the 91X as well.

http://www.theturboforums.com/smf/in...topic=108600.0



Here is the FI-91X...

http://www.turbobuick.com/forums/1928046-post39.html

DrTurbo

iTrader: (3)

Also their is a GT4755 hyrbid coming out. Will be the GT47-88 comp wheel with the GT55 turbine wheel in a GT42 size platform if space is an issue.

C Murda

iTrader: (24)

i know its a lot on the motor but what can be done to hold that kind of power 800+RWHP on the street and still run on 93oct pump gas? my car's suspension is set up entirely for the street i like to go to the track once and a while, im not entrely focused on times at the track cause really id have to change my shocks/springs and a lot of other things. what i really want is to lay down 800+RW numbers on pump and be able to use it on the street and take out some 1ltr bikes. and in order to do so id need to stay in boost and handle it. short block is fully forged and built for it just would like to know of the added things i should look into in order to handle full boost at longer than "on the dyno" periods?

Pro Stock John

iTrader: (34)

The end goal is 800rwhp on 93 pump, so plan on building a combo that make 800rwhp on pump, and can make more on race gas. I think the mistake that some have made is to create a maxed out combo that made 800rwhp on the dyno a couple of times but with a big dollop of timing and with little to no regard for the IAT's.

Who is your engine builder/tuner/kit builder? See what they say but I'd be planning on a 427ci that is around 8.5:1 - 9:1, run a 91 turbo, a good A/A (I hear that some shops really like the Bell cores), and a thorough fuel system.