Hey guys,
Just bought a 92 5 speed RS with the goal of putting the car into the 10s or 11s. Here's my question: Whats the best engine/engine mod to get this done? Id like to stay away from nitrous if I can. Whats the best route here? Supercharging the engine that's there? Dropping in a 350+ crate motor? Swapping out the RS engine for a GN turbo 6 and then getting some bigger turbos? Id like the car to be streetable if I go a turbo route, i.e. I don't want a monsterous lag time. Any help/ideas appreciated.

-BlakeM

 

You're into a highly modified supercharged small block under a lot of boost. The rest of your car will have to be altered to put the power to the ground. You're talking big money, dude.... on the order of $15K - $20K.

 

Thats fine, the money isnt the most important thing, the speed is. What kind of small block and what kind of supercharger setup are you talking about?

 

Well, a 9:1 compression 350 with good heads that flow at least 270 cfm, MiniRam, blower cam, and a Vortech S-trim supercharger with 12 psi of boost will make you a solid mid 11s flyer. With proper tuning you could get into 10s on that same combo. The only reason I suggest using a supercharger is because you want to remain completely streetable. It's nearly the only way to accomplish what you want.

You will also need to trade your tranny and rearend for something more substantial. I'm using a Tremec TKO 5-speed and a Strange Engineering 12-bolt. There are other trannys out there but I would encourage you to use the Strange 12-bolt. It's very durable and more efficient then a Ford 9". You'll also need a complete suspension upgrade including subframe connectors and a roll cage. The roll cage is mandated by track safety rules for the times you want to run. If you don't care about running at a track then you don't need it, although it is recommended just for general safety.

 

go witha bigblock for thos kinds of numbers... it'll be cheaper.

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What kind of HP #s am I looking at here? What big block?

 

Calculate a power to weight ratio. Although my car hasn't been weighed yet with the big block I'm guessing from how much it weighed when I had a small block that it's now about 3100 pounds. Altitute corrected HP based on 1/4 mile MPH I'm pushing just over 500 HP at the rear wheels. Altitude corrected I should run 10.6's at sea level.

The lighter you can get the car, the less HP you need. You need a lot more HP to push a 3700 pound car into the 10's than you need with a 2800 pound car.

Go with a big block. The bigger the better. 454 is the most common but if you have the money, go for a 502. It's easier and cheaper to build a mild 500 HP big block than it is to build a small block with the same output.

You don't wan't to use nitrous but are happy to use a supercharger or blower. Why? Internally the engine doesn't care what kind of boost it gets. They all do the same thing and under extreme use, can all destroy a weak engine. A nitrous engine can be extremely streetable.

As stated above. The engine alone won't let you run 10's or 11's. The rest of the car needs to be modified to handle all that power. All the HP in the world can't help you if you can't get it to the ground.



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87 IROC-Z SuperPro ET Bracket Race Car
461 naturally aspirated Big Block

Best ET on a time slip: 11.242 altitude corrected to 10.69
Best MPH on a time slip: 121.52 altitude corrected to 127.76
Altitude corrected rear wheel HP based on power to weight ratio: 504.5
Best 60 foot: 1.546

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Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

Whew! Glad I decided to race a V6! I couldnt afford to put a V8 into the 10s or 11s!

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Mike
1989 Turbo Trans-Am
11.25@121.25
Daily Driver

1998 Trans-Am LS1 6 Speed
13.10@106
Slow POS sitting in the Driveway awaiting repairs and then its For Sale. No More V8 Cars for me.

 

Anywhere from 500 to 700 Hp depending on how deep into the 11 and 10 second range you want to go. A 550 Hp motor will put you in 11s on the street tires if you set up your suspension properly.

Tthe reason I didn't suggest a big block is because you wanted good mileage. With a supercharged small block you can run the number and still get 20+ mpg.

You're talking about building a very serious street car. This isn't done every day and very few people have street cars that can run 10s. That kind of car is nearly insane and can get out of control very quickly on street tires. A 400 Hp street car is more than sufficient to clean house on a daily basis and will cost much less.

TTA, you're one of the lucky guys with a DANA 44 rearend. The rest of us have to build from scratch! That costs big bucks!

 

I don't want to run nitrous for general use that is. I race quite a bit around town, and a blower is just more convenient, no tanks to open, no switches to flip, etc. Ill probably put nitrous in for track runs. So Im looking at a built 454 w/ a supercharger to keep it streetable, and pretty much rebuilt and stronger everything right?

BlakeM

 

No. A built 454 with a supercharger would be insane and make in excess of 800 Hp. You want a supercharged small block. It will get you into 11s with ease and into 10s if you tune it properly. My '94 Vette had a supercharged 355 LT-1 with a stock cam and stock computer that got 26 mpg on the freeway and could have pulled mid 11s on slicks. In street trim it was good for nearly 12 flat at 122 mph. You could easily do better by matching the cam and properly tuning fuel delivery. It dynoed 500 Hp. That's your starting point. You could easily bump that same motor up to 600 Hp with a blower cam and proper tuning. It currently has 48K miles and still running low 12s on street tires. E-mail me at littleborgy@yahoo.com if you want the specifics of that engine build. There are other people on this board with some pretty wicked small block setups. You just need to get them to talk .

 

Actually, TTAs came with the Same Austrailan 9-bolt that came in V8 F's. I just bought a Dana 44 with 3.31 gears though... Damn thing cost more than it did to my car in the 11s

Im doing a rebuild on the V6 now, so I guess I'm up with the rest of you guys on spending money... 2500 for the Bottom end, 2500 for the Top end... Blah... Still need a Good Convertor as well. Time to replace the stocker



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Mike
1989 Turbo Trans-Am
11.25@121.25
Daily Driver

1998 Trans-Am LS1 6 Speed
13.10@106
Slow POS sitting in the Driveway awaiting repairs and then its For Sale. No More V8 Cars for me.

 

Actually NOS is more streetable then a blower. I say this because NOS is only stressing the motor when you are using it while a blower is stressing the motor the whole time its running. Also it takes about 20-40hp to turn a blower so you are using HP to make HP. Another point is the cost!

The main reason you see alot of people blowing motors while using NOS is because the put too much in a motor that isnt built for NOS.

 

Not entirely true. The blower doesn't create boost unless you crack the throttle blades nearly wide open. During normal operation it uses a bypass valve so the motor works just like normal. But give it some gas and away you go. Also, the power comes on much more smoothly than nitrous and can be used year in and year out without running out of juice. Nitrous is a real shock to the drivetrain and on street tires people often burn their tires off or hit the rev limiter instantly. There isn't as much throttle control. It is true the inital cost of a blower setup is fairly substantial but how much do you spend a year on nitrous and how often do you activate it? A blower motor can be run for 2 seconds or 5 minutes. If you used your nitrous as much as I used my blower you would be filling your bottle twice a day.

[This message has been edited by QwkTrip (edited June 05, 2001).]

 

what you need to do good sir , to really go fast is swap that anchor out for an awesome! ford "5.0" just kidding man...

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87GTA ,10.5:1,4-bolt 355,afr 190's, super ram ,stock poerted base,58mmTB,24 lb FMS inj. ed wright chip, .510/230 (nr) 1&5/8 hooker shorty's, flow master single 3", 2800 ameri-torque non lk-up, 3.73. best to date with stk 48mm tb and lack of traction in 1st gear netted me a 12.9 @110mph /91 TA daily driver LB9 A4 2.73,