My Twin Turbo 401 build

[Orr89RocZ]

Well it was suppose to be a secret but i let it out in the other thread that something was up so here i am explaining what the hell I am doing now

My motor currently is a blast. I love the way it sounds as i am a n/a guy. However its loud and i dont drive it as often as i want because of it. I love the way nitrous feels. 10 second cars are quick as hell but 4.5 passes per bottle at 150 shot is less desireable. And that power isnt instantly available on the street as i dont drive around all the time with the bottle open and heated.


SO, i've decided to sell off a few things and buy a few things.

Here's my plans/intentions with the car

I want somewhere between 650-750whp with 10-15 psi. Fairly mild. 93 oct possibly with meth injection
I want to run somewhere in the high 9's or atleast trap 135 or greater hopefully.
May have a 6 speed trans
Quiet enough to drive anytime i want but we'll see. Will use same exhaust system, just have to connect down pipe to existing exhaust.
Car will NOT get a 10 pt cage to be legal. My current harness belts are not NHRA legal and i'm not gonna get that anytime soon either. My track is IHRA and after a 9 second pass they will tell me to keep it above 10.0 and under 135, no problem.
Thats about it, summarizes my goals. I fear 700whp is really starting to stress the 4 bolt block so any power made above that will be track only in kill mode.


Heres the build plan so far, subject to change as time goes on ofcourse:

383 will keep rods/crank/block but use JE 28cc inverted dome pistons i think for 8.8 to 1 compression. Considering wiseco 20cc for 9.3 to 1 compression but 8.8 is safer for more boost if i decide to run alot more. Mahle has some pistons for i think 9.3 to 1 compression as well that are 200 bucks cheaper but not sure what to do there

Keeping my heads, keeping my Stealth Ram.

Cam will be custom Mike Jones grind. Probly somewhere in the 228 range on intake, mid 500's lift. 113-115 LSA i would think but i'm not sure yet. Want it to peak in the 5800-6000 rpm range but that may be optimistic. I can make the power in the 5500-5700 range just as easy and its softer on parts

Turbo will be budget: S475 or S478 by borg warner airwerks or the new Master Power T76. S400 stuff i believe flows abit more and is good for more power down the road but is about 300-400 more bucks. It will be T4 flange

BBS designs single turbo manifold i have. its more of a log type. Needs some work for my setup, as its designed for a 305/350 with mild turbo. Needs new wastegate tube installed, Going to run 50mm gate I believe, probly JGS as its more budget

3" air intake piping, VS racing intercooler but i may run two small ones on both sides of my radiator in the open space i have under the bumper, OR run one large one in front of the rad. That way is easier but air flow to the rad will be compromised, and it will overheat more. Not good.

Injectors possibly siemens 63 lbr's with higher pressure to make them like 66's or just get SMP 79 lbs. Should feed my power i hope, the 79's i think are good to 850-900hp.

Fuel system gets abit more complicated. My current system is only good to 600hp i THINK. Some claim 700 but i have no answer on that yet. I'm gonna go with a Aeromotive A1000 pump with stock sumped tank. Aero's voltage controller for street use so it dont overheat. Would like to run 6an lines as i beleive thats enough but the A1000 is setup for 10an fittings. I'd have to neck down, as my rails are only good for 6an. They should feed the power but if not, i have to go with a custom rail or something. They are 3/8" tubes and i'd love to have a 9/16 or 5/8


Gonna try to fit a 4inch downpipe. into my current exhaust. If not neck it down to 3.5" and then back to 4. My firewall is TIGHT


ECM control will be a 90-92 fbody 730 ECM repinned as a turbo cyclone/typhoon 749 ecm. Wired into my current factory harness. I'll be running a updated cyclone code called code 59. It seems to be a nice system but i wont be using all the features.



That about sums up my build plans. Whats great is I basically just have to purchase the turbo and turbo parts and fuel system to make this work. ECM is cheap, my headers/pistons/nitrous kit and other parts i wont use will be sold. I have buyers for them all right now. So basically I am just replacing things for free or very little total cost input. The big adders are the fuel system and turbo/turbo parts/exhaust piping. Oh and injectors are expensive but i can sell my old ones for 150-200 or so i hope. Help offset cost.

I have a buyer for my 700r4 auto trans if i decide to buy a T56. I'd just need to sell the converter and get a LT1 flywheel with new clutch to hold the power which probly wont be cheap. Not sure if i'm gonna do the T56 yet but i found one for sale for a decent price so we'll see

Stay tuned

[Stippy17]

Decided to let the secret out eh?



Ill definitely be staying tuned to this thread..

[SCU]

Looks like you thought this out. lol

[Orr89RocZ]

i've been planning and researching alittle while now. I got most of the details figured out

AFter looking at the mp T76, i dont like how small the turbine wheel is. Its using the same turbine as the T70 but just a larger compressor. I may do the S478 as i think it will kick some ass

[ceracer33]

i knew u were gonna go turbo lol. i would suggest staying with the auto trans though. especially making that kind of power, u are going to have a hard time keeping a clutch in that thing.

[Orr89RocZ]

yeah i would have to go soft off the line at the track and during shifting it may be rough on the trans at WOT. But i always wanted one

I dont think my 700r4 will like the new motor too much either tho

[Stippy17]

TH400 like Im going with perhaps then?

[SCU]

Originally Posted by Stippy17

TH400 like Im going with perhaps then?

He needs OD for those 1,000 miles he drives a year

[Orr89RocZ]

I'm not sure i want an auto, esp. a 3 speed as i will be driving it much more often i think. Or i hope

6 speed will do ok with the power for now as long as i dont beat on it too much which is like rare as when i drive i beat on it. I gotta research clutches for this type of power to see whats available. I found my tranny and i have to decide if i'm gonna buy it or not

I may just pick it up now since i found one for a deal and sell later if i have to, if i decide i want the auto trans

EDIT: hahah next year i'll be closer to 5000 miles i hope. cant go over that tho

[SCU]

Originally Posted by Orr89RocZ

I'm not sure i want an auto, esp. a 3 speed as i will be driving it much more often i think. Or i hope

6 speed will do ok with the power for now as long as i dont beat on it too much which is like rare as when i drive i beat on it. I gotta research clutches for this type of power to see whats available. I found my tranny and i have to decide if i'm gonna buy it or not

I may just pick it up now since i found one for a deal and sell later if i have to, if i decide i want the auto trans

EDIT: hahah next year i'll be closer to 5000 miles i hope. cant go over that tho

Plan on visiting MIR?