99gt302

Well im back in a stang finally. Here are the Specs:

99 GT - Automatic
NON Intercooled Paxton Novi 2000 (10lbs pully)
Trick Flow Intake Manifold & Plenum w/ cobra twin TB
No Cats w/ H pipe and full exhaust on stock manifolds
3:73 Gears
Rebuilt bottom end (details below)
Draw Through MAF Setup
Diablo Sport Predator Tuner
RC Racing Injectors (P/N SL-270) - 270cc maybe? 26lbs/hr?
Lightning MAF(havent looked yet to double check)

Stock fuel pump I believe - what do I look for? Where would a BAP be?

Ok so I bought this car a few days agao and wanna make sure its all good before I go out raising hell. I was told the guy installed the blower, made too much boost/power and cracked 3 pistons. He had the motor bottom end rebuilt and its supposed to be able to hold around 800HP(couldnt find the papers, so im thinking its prob stock??).

I have no idea how it was tuned, it has a custom tune in the diablo sport tuner that is installed on the car, anyway to tell if this is the correct tune for how the car is setup?

The car runs smooth except it will surge at idle sometimes and die every now and again. Makes boost pretty quick(around 3500rpms is at full boost) and is smooth running and seems strong. I have done a few WOT pulls and saw 11LBS on the gauge but am scared to really give it all its got before I get this tune figured out. What is the best way to go about doing this? And would I need a re-tune after installing FMIC and converting to blow-through?

Also could one give me some info or a link on how to learn about fuel duty cycles, air/fuel, timing, spark advance, etc etc? Thanks!

I just wanna make sure the car is running rite and has everything needed.

I will be getting a dyno tune, but only after long tubes, new exhaust, stall, power pipe, and pulley - so for now, I wanna stick with this diablo sport and see how she does.

zero2005

uh.... first off, you wanna drop the psi down if its a stock bottom end. i would be cautious about anything over 9 psi. you'd need to swap the pulley to do this.

is there a reason you wanna convert to blow-through? if its mostly set up, really all you would need is a tune and be on your way. what are your goals?

unless there is a way to verify that the motor was rebuilt, i would treat the block as stock.

you need bigger injectors and a bigger fuel pump. check out the SVT focus fuel pumps [255lb/hr] they're like 90$. as for fuel injectors, i would recommend a minimum of 42lb'ers for you, depending on your goals. you can find a good used set pretty cheap.

your *probably* gunna need to take it to a dyno... you already have the diablosport - so find a shop that deals with them. i'd find out who tuned the car to begin with. if he had the supercharger put on, it had to get tuned by someone, or that motor would have poped already, and even still, i would be weary if he's saying the pistons have been damaged before, and its still running the same tune - it could be the tune thats causing it to crack.

for a boost a pump - you'd have to go to Kenne Bell. if your only lookin for around 400-425 rwhp, a SVT focus pump + 42lb injectors should get you there. any higher, and your probably better off getting a cobra tank with dual pumps, OR getting a sumped tank with in-line pumps.

Mustang_NTriangle

it is probably stock bottom end and would change the pulley to run 8 psi get it re-tune. If the guy spent money on motor he would have had receipt. Hell - I don't keep receipts but certainly keep my motor receipt.

Good luck with you new car.

99gt302

thanks for the info! The injectors are RC Racing SL4-270 injectors.... Injector size: 270 cc/min injectors(25.7 lbs/hour)

I am looking for around 400rwhp and no more... will these injectors be fine?
would i HAVE to replace the fuel pump?

zero2005

yes, at minimum you need to replace the pump and you need bigger injectors(42lb/hr). dont skimp on fuel. thats probably the reason the guy that owned the car before you cracked the pistons. you'll need a new tune too.

what MAF are you running? if its a stock MAF you'll need a better maf too... there's plenty of options but find what your tuner would like as it will help them out.

edit: you'll want to take a look at your spark plugs too. i recommend NGK TR6's. install them before hand so your tuner doesnt have to, or you dont go home from the dyno unhappy with your results...

99gt302

Few Updates on the ride: 42s are installed and tuningss sent me a base file tune for the injector slope. Verified the bottom end has diamond pistons, eagle rods (everything else stock) The guys at boosted performance in mooresville, nc built the motor. I talked to them along with the guy there who assembled it. Waiting on intercooler pipe kit and everything is ready for the dyno, this project is almost done!

NaughtyGeek

Did you get a fuel pump? If not, you're going to run out of fuel around 4500 - 5000 RPM.