Well i am new so hello. I recently purchased a slow 98 gt convert. Southern no rust no winters great shape, great compression test, 90,000 miles. Bad convert top and a friend with a newborn equates to 2800 cash. So after alot of research i decided to go and spend the next year making a turbo turd. I kreally want a nice car i can drive in the summer, run on the street and strip. I work at roush as a fabricator in ford prototype and crash programs. Ive worked with ford gt (40) on the svt side, ive worked with cobra jets, ive had my hands on some cool sfuff. What i dont know is how to choose the right turbo and components for my build.
My plan, i want to fabricate eberything on my own. Im great tig welder, sheetmetal former, fitter, and machinist. I have been doing research and i believe a 62-1 turbonetics is the way to go, but im not sure what AR or what spec i really need? Also are twins worth it if i decided to go that route? As far as othe waste gate and bov, I`m not sure what to go with, i have heard of budget builds using ebay junk, but i dont want any issues on my first turbo build.
Secondly i want to run this set up on a stock 4.6 with npi heads, and stock cam springs, what kind of boost can i use with out floating my valves? Also is it ok to use two tunes and adjust for more boost when needed? I plan on going with a mmr forged set up down the road and i dont mind pushing things a bit it is not a dd.
Third, for the fuel system is a 255 pump, lightning maf, and 42lbs right? How are you guys setting up the bov with the maf?
Fourth any thoughts on good places to shop i want to keep this under 3500, not including the upr k member set. I am about to do 3.73 gears and a new top at roush this month. Thanks for your time, look forward to laying rubber.

 

Oh and i was planning on running my hotside like the hellion kit is there a better way?

 

I'd go with at least a tc70 for that. Tial, JGS, and Turbosmart all make great stuff. Also, don't do 3.73's, 3.27's are about perfect with 26" tires.

 

BOV goes before the maf so the ecm can base fuel on the air going to the engine.
Get a recirculating bov if you don't want the noise.

3.27's has been stated for years as the best compromise gear for a turbo on this site.

Where do you cut corners on a 600hp engine?
Stock springs = bad idea

66mm is a good starter size turbo but people seem to out grow them pretty quickly.
With your budget contraints, like jr said, tc70 is a good compromise.

 

Those heads are going to hurt you . you can buy new PI heads for $400 each with cams and better springs or you can port the npi heads , they have a lot of meat you can take out.

 

Yeah the npi heads suck... this i know. I plan on replacing the whole engine in a year or so. I will be using a mmr shortblock and cnc ported pi heads with stronger springs and turbo cams. However for the next year or longer i will be boosting the stock npi for money reasons. I suppose if i blow a rod no biggie. But if i send a valve into my turbo i would be pissed. Thx for the input... i plan to look into the 76. I have a maf from a ligjtening thought it was better to mount it befpre turbo intake? Ri would rather have a bov into atmosphere though if possible. As far as gear damn i didnt know that, 373 seemed like they eould be awesome, how come there too much gear? Im curious as to the reasoning i dont understand?

 

Have the t45 trans going to upgrade tova t56 someday

 

Taller gears help load the the turbo better. You'll be in boost quicker and can stay in gear longer. Sounds a little backwards, I know, but turbo cars generally like less gear.

 

Don't spend a dime on that engine. Get everything up and running with what you have and build something better as money allows. We've made 410 through a t56 for several years with a stock npi motor, it may not be "safe" but it hasn't given any problems yet and if it does, oh well. I just don't see the point on wasting money on something you won't be using in the long run. Get your feet wet with what you have.

 

Man thanks for the input, good to hear something good about an npi lol. I already have an 8.8 with 373 ready to go in.... sob i should of known. Well is the 2.xx better from the stock set up or the 373, because for now thats whag i got? Im super interested in ur build, did you swap heads and go with the higher compresion? What springs are you using? How much boost can i run stock? Ibe heard and read alot of different things, anywhere from 7-12. Ive added up the numbers seems at 12 or .8 bar i would be close to 400 rwhp, which is probally close to high 11 low 12 sec e.t. zone with good shifts, traction, reaction, prayers. Im aiming to run at least 400hp and more down the road. I really wanted to do a turbo build for a long time, ive done alot of exhaust, headers, hot sides, and cold side stuff at work, but i always worked to manufacture prints/spec in prototype systems i never learned or put togeather my own. Its not like building a csge or anuthing else, its alot of math that im just not aware of... gears go figure is part of that.

 

Sorry about the bad grammar, im using a phone and it is a freakin pita

 

Man thanks for the input, good to hear something good about an npi lol. I already have an 8.8 with 373 ready to go in.... sob i should of known. Well is the 2.xx better from the stock set up or the 373, because for now thats whag i got? Im super interested in ur build, did you swap heads and go with the higher compresion? What springs are you using? How much boost can i run stock? Ibe heard and read alot of different things, anywhere from 7-12. Ive added up the numbers seems at 12 or .8 bar i would be close to 400 rwhp, which is probally close to high 11 low 12 sec e.t. zone with good shifts, traction, reaction, prayers. Im aiming to run at least 400hp and more down the road. I really wanted to do a turbo build for a long time, ive done alot of exhaust, headers, hot sides, and cold side stuff at work, but i always worked to manufacture prints/spec in prototype systems i never learned or put togeather my own. Its not like building a csge or anuthing else, its alot of math that im just not aware of... gears go figure is part of that.

 

Man thanks for the input, good to hear something good about an npi lol. I already have an 8.8 with 373 ready to go in.... sob i should of known. Well is the 2.xx better from the stock set up or the 373, because for now thats whag i got? Im super interested in ur build, did you swap heads and go with the higher compresion? What springs are you using? How much boost can i run stock? Ibe heard and read alot of different things, anywhere from 7-12. Ive added up the numbers seems at 12 or .8 bar i would be close to 400 rwhp, which is probally close to high 11 low 12 sec e.t. zone with good shifts, traction, reaction, prayers. Im aiming to run at least 400hp and more down the road. I really wanted to do a turbo build for a long time, ive done alot of exhaust, headers, hot sides, and cold side stuff at work, but i always worked to manufacture prints/spec in prototype systems i never learned or put togeather my own. Its not like building a csge or anuthing else, its alot of math that im just not aware of... gears go figure is part of that.

 

Man thanks for the input, good to hear something good about an npi lol. I already have an 8.8 with 373 ready to go in.... sob i should of known. Well is the 2.xx better from the stock set up or the 373, because for now thats whag i got? Im super interested in ur build, did you swap heads and go with the higher compresion? What springs are you using? How much boost can i run stock? Ibe heard and read alot of different things, anywhere from 7-12. Ive added up the numbers seems at 12 or .8 bar i would be close to 400 rwhp, which is probally close to high 11 low 12 sec e.t. zone with good shifts, traction, reaction, prayers. Im aiming to run at least 400hp and more down the road. I really wanted to do a turbo build for a long time, ive done alot of exhaust, headers, hot sides, and cold side stuff at work, but i always worked to manufacture prints/spec in prototype systems i never learned or put togeather my own. Its not like building a csge or anuthing else, its alot of math that im just not aware of... gears go figure is part of that.

 

The guys are right about the 3.27's. I just switched from a 3.27 to a 3.73 with a 28" tall tire and the boost curve is completely different. I think it will atleast be a good starting point. Still maxes out boost but it doesnt flat line like it did with the 3.27's. Anything you know about gear ratios when it comes to turbo's throw it out the window. LOL. I built my junk box to use as a learning curve as this is my first turbo build and I'm tuning it myself. It's still running strong with all stock high mileage parts and 12lbs on stock springs. When my boost controller arrives I'm gonna turn it up and see how far it goes before the valves float(I think they are close). The t45 will be the first thing to check out most likely... Ask me how I know.

 

Sent you a pm

 

What are your goals for the future motor? You should be able to find a turbo that works ok for now but meets your goals down the road too. If you're lookin for 400 now and 600 later, I'm sure a tc70-76 will work fine. If you have room go with a regular t series 70-76.

 

The motor is 100% stock, other Han valve springs. The car was originally built just because my buddy was bored with his car and had quite a bit of stuff laying around already and had no intention of being turned up this far. EBay intercooler, 6766 turbo (I think), 42 pound injectors, single 255.... Just your standard stuff.* It's making 410 with no filter and a very short open downpipe. It was floating the valves with 12psi at 5000+ but drop-in comp springs fixed that. Idk how safe this tuneup is for an npi 4.6, but it's been alive for quite awhile. Probably going to rrealty put some boost to it soon and see just how fast one can go.

 

Awesome stuff, with my build i wanted to get in and have fun. I bought the car for the intent of a fun car only. I want to be different alot of people supercharge, i want something else. A turbo car seems to have awesome possibilities. Im not sure where this car project is going to end up hp wise. But for now 400+ rwhp amd 11s are an achievable goal for next year

 

As far as having room i can always make some... haha ford has a habit of jaming motors into all sorts of cars, i did a sho tt enfine in a transit lol i always wondered why they did that. Anyways room can always be made, but ive luked the looks of under the bumper... only downside is a scavenger pump from what i can tell.