gt supercharger ?

ghostriders

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Sep 20, 2009
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Hi guys - I am new to the forum.

I have an automatic 4 speed 2002 GT convertible, w/full Saleen bodykit, light bar, suspension/sway bar and twin flowmaster 'airboat' exhaust w/magnaflow tips - I am about to supercharge it:
- series iv charger
- lighting force front heat exchanger
- chicane inter-cooler
- JLT cold air intake
- lightning force super-charger coolant tank
- 42 lbs ford racing/bosch injectors
- everything else related to the charger (intake manifold, etc.) saleen

it is a stock GT engine, and have had many opinions and thoughts on max horsepower/boost that is safe for the engine, given that 'safe' is a relative concept - I have heard everything from 'don't worry about it if you don't redline it' to 'keep it at 350 rwhp to 375 rhwp' - supposedly the charger can make more horsies than is safe for the engine, and I don't particularly care to spend the coin beefing up the engine - it is running great w/ only 29k miles; in terms of boost I have heard a range of 5-6 to 7-9 as 'safe' - I have talked to many pros at saleen, stage 3 motorsports, lightning force, chicane, tork tech, etc.

yeah, I am having pros install it and tune it - they say it can be a 12 second car if we tune it right...on to the 'safe rwhp ?'...

any comments or opinions on this?
thanks alot........rrrrrrmmmmmm.......
 

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Stock rods are on borrowed time with much more than 400 hp is what I've always heard. I'm not sure I'd want that much power _and_ sticky tires on a vert. If you do, make sure to beef up the torque boxes and get some good subframe connectors and strut tower brace.
 
I would begin to worry at 400 or more rear wheel HP on a manual car. With an estimated 15% power loss, this translates to about 460HP at the crankshaft. I'm at ~390 or 448HP and that's plenty for me. Even then I still worry once in a while. All of that power is going through eight of these things:

46perf12.gif


In addition, the pistons are cast hypereutectics with thin upper ring lands:

46perf16.gif


Check out how thin the band of material is above the upper ring land: Imagine how quickly it could be broken by detonation...

Keeping the tune conservative and the boost moderate to keep power output below a reasonable limit is the only way to be sure you won't hurt anything (and even then, by definition, you're going to be that much closer to the edge no matter what...)

With an automatic, I'd probably try to shoot for a rwHP figure of right around 360 which is about 430fwHP (20% loss assumption.) I assume that Saleen's tune is pretty conservative. Resist any temptation to try to optimze the tune for more power, to go down a pulley size on the blower to up the boost because you "get used" to the power or get whupped by an Evo on the on-ramp and the rods and pistons will thank you.
 
you can get a much better blower for the price than the crappy saleen blowers. you will be lucky to break 400 to the wheels with an OD crank and smallest blower pulley you can buy.

i would buy a KB over the saleen blower any day! hell, i'd rather have an s-trim than the saleen one. there are lots of guys making in the mid 400's and not having any issues. if you want to keep the stock internals (you WILL want to upgrade for more power) i'd keep it around 380-410 with an auto car. i would make sure the AFR isnt above 12.0 and keep the timing around 12-14*.
 
you should first decide the type of blower you want, since there are two different primary categories; centrifugal and twin screw/roots style. Kenne Bell (twin screw) will give you full boost nearly off idle, which makes it a torque monster and a fun toy on the street. If you want traction off the line, centrifugal blowers build power in a linear fashion so they don’t hit as hard on the bottom but don’t have the lag of a turbo. In this camp you have the Novi 2000 or Vortech (model depends upon mods and desired results). I went with a Kenne Bell and wouldn’t have it any other way unless it was a track only car. What the guys are telling you about the pistons failing at around 400hp is right. Mine blew with 66k miles just after putting down 405lbs of torque.
 
If it were mine, I'd boost lightly now (350 RWHP) and build a forged bottom end that you can drop in when you are ready. I'd also start with a Teksid aluminum block. They can be had around here for $150 at the pick-a-part as a complete engine. The B-heads do well with forced induction and high revs so you may be able to use most of the engine depending on your goals. If not, ebay will take them and you will have $75 invested in a very strong and very light block.
 
you should first decide the type of blower you want, since there are two different primary categories; centrifugal and twin screw/roots style. Kenne Bell (twin screw) will give you full boost nearly off idle, which makes it a torque monster and a fun toy on the street. If you want traction off the line, centrifugal blowers build power in a linear fashion so they don’t hit as hard on the bottom but don’t have the lag of a turbo. In this camp you have the Novi 2000 or Vortech (model depends upon mods and desired results). I went with a Kenne Bell and wouldn’t have it any other way unless it was a track only car. What the guys are telling you about the pistons failing at around 400hp is right. Mine blew with 66k miles just after putting down 405lbs of torque.

thanks for all the input - very helpful - I assume the above post refers to 405 lbs of torque at the rear wheels? just checking - I am thinking of about very conservative boost, and targeting in the mid-300 rwhp range; also, the saleen series iv blower is a twin screw, and a much better design than the series ii; I already have it (used w/12k miles, no play, spins free by hand and the local race shop that seem to know their stuff, thinks its in great shape - I have pieced together the rest of it and about to start the install...
 
thanks for all the input - very helpful - I assume the above post refers to 405 lbs of torque at the rear wheels? just checking - I am thinking of about very conservative boost, and targeting in the mid-300 rwhp range; also, the saleen series iv blower is a twin screw, and a much better design than the series ii; I already have it (used w/12k miles, no play, spins free by hand and the local race shop that seem to know their stuff, thinks its in great shape - I have pieced together the rest of it and about to start the install...

yes, that was 405 at the wheels. Essentially, I wouldn't suggest beyond 9psi of boost from a twin screw without race gas or meth after the blower. 10 with a good tune is pushing it. Conservative boost is 8 psi. I don't know of any reason to do 6 if you can do 8 psi safely. Beyond that it does start to get hairy. Make sure you have enough fuel pump as well. Your 42lb injectors and stock fuel rails will not be a limiting factor at that boost level range. My experience is solely with the 32v version of the 4.6l, and yours being a 2v you might have more play with boost depending upon how much heat your blower makes at those boost levels. There are more than a couple variables in play...
 
ps - canada is a colony of the USA w/funny accents

OK, canada's not all bad :canada:

He was merely pointing out a typo that created confusion, confusion being the key word here...the meaning of your post was lost due to the typo. The cheap shot PS of yours was really out of line...I'd think someone with 5 posts to their name would think twice before making such remarks. The attempt to mop-up the mess was equally sad..."not all bad"? (Canada should be capitalized as well) Gee, you know how to make a good first impression... :rolleyes:
 
He was merely pointing out a typo that created confusion, confusion being the key word here...the meaning of your post was lost due to the typo. The cheap shot PS of yours was really out of line...I'd think someone with 9 posts to their name would think twice before making such remarks. The attempt to mop-up the mess was equally sad..."not all bad"? (Canada should be capitalized as well) Gee, you know how to make a good first impression... :rolleyes:

OK, I apologize - you guys have been great giving me quick feedback on my ?...BUT, I did think that most high-horse power mustang guys had thicker skin...:nono::lol::nono: but that is my biggest complaint of the mustang - maybe improved since the 1999-2004 series - thin sheet metal :rlaugh:

just kidding - again, thanks for the feedback...