Building a forged motor

[drxlcarfreak]

I am getting ready to start researching and sourcing parts to build up an engine for some high horsepower. Right now I have a 95 Talon TSI AWD and have been slowly picking up supporting mods for the TD06-20G that I will be getting in a couple weeks, but I know maxing this turbo out wont be enough for me for too long.

I plan on building a motor to withstand 8-900HP (only planning on around 6-700, but would like extra headroom for tuning mistakes and just to help with the longevity of the engine), via twincharging.

My first in probably a long series of questions that I cannot seem to easily find via the search function is if I am building a forged engine is there any difference in reliability/price between a 6 bolt and a 98-99 7 bolt? Because I already have a 7 bolt trans, would I need to get a different trans if I went with a 6 bolt block? I was kind of leaning towards a 6 bolt originally because they have lower compression options, which would help me out with getting higher boost levels without detonation, but if the difference is negligable like 7.8:1 vs 8.0:1 and I would need to fit a new trans then maybe a built 99 7 bolt it is.

I apologize if there have been threads on this, but in my searches, it really only related to the durability of stock 6 bolts vs 7 bolts.

 

[drxlcarfreak]

I think with this setup you may want to look into going auto. Just sayin, Its going to be hell trying to drive this thing otherwise.

That could very well be true. Haven't thought too much about manual/auto yet. Would like to stick with manual if I can for now.

How did you calculate 80+ psi being needed? Pressure doesn't make power, airflow does. Also i would first build a 400 horse setup before even attempting to go for anything more than that. You are way over complicating this. A good single turbo will be plenty.

There are formulas using the ve of an engine to give you necessary numbers. I don't know them off the top of my head

That is correct... I did a quick calculation of the airflow needed using:

Airflow Needed (lb/min) = HP*AFR*BSFC/60
I estimated the AFR to be about 11.5, and the BSFC to be .55 which meant I needed about 105lb/min of air flow.

I plugged that number into a MAP required equation:
MAP=Airflow * Gas Constant * (460 +Manifold Temp) / VE * RPM/2 * Displacement

Airflow = 105 lb/min
Gas Constant = 639.6
Manifold Temp = 130 F
VE = .9
RPM = 7200
Displacement = 122 in^3

This gave me 100 psia, or 85psig.

You are right, I will be doing things one at a time. As soon as my 20G shows up I will start working towards the 400hp.

The MAIN difference in reliability (even with swapped parts) is teh 7 bolts are known to kill thrust bearings and crank walk,

So even with forged parts the 7 bolts can still walk??

 

[ed1380]

forged parts wont make a difference in crankwalk. biggest difference to prevent crankwalk is the revised main bearings in the 98-99 blocks.

heres a cool link
http://www.turbofast.com.au/tfcalc.html

 

[JdawgDSM1G]

whats up bro, i just wanted to ask, how much did you plan on spending on the build? i have pretty damn close to 800hp talon that's a single turbo setup and it sucked me in for alotttttt of time and money "and i did all the work myself so that saved some $" i can only imagine what a biturbo or twincharged build would cost. deff alot of fabrication.

 

[drxlcarfreak]

forged parts wont make a difference in crankwalk. biggest difference to prevent crankwalk is the revised main bearings in the 98-99 blocks.

heres a cool link
Ray Hall Turbocharging - TurboPower java calcultor

Cool, thanks for the heads up.

whats up bro, i just wanted to ask, how much did you plan on spending on the build? i have pretty damn close to 800hp talon that's a single turbo setup and it sucked me in for alotttttt of time and money "and i did all the work myself so that saved some $" i can only imagine what a biturbo or twincharged build would cost. deff alot of fabrication.

I haven't sat down yet to figure out exactly what it would cost, but I figure about $2500-3000 for the short block, $2k for the head, $3k for upgraded transmission, $1500 for an upgraded transfer case, $900 for driveshaft, rear axles/hubs $1800, front axles $800, Upgraded clutch $800, upgraded differential $1000, upgraded brakes $900, upgraded suspension/coil overs $900, $1500 on turbos charge pipe etc, plus probably about another $1000 for miscellaneous small parts/bolts etc.

Do I have any gaping holes here?

 

[CrawlinZX14]

I hate to burst your bubble, but you will have easily over 25k into the engine alone on what your talking about doing. Because your short block is going to cost you a LOT more than your thinking. Not to mention, do you really think your going to street drive this? How the hell are you going to cool it? I have put over 5 grand into a head before, and that was port n polishing, CC the head, flow testing, oversized valves, all new hardware, springs, cams, and the basics. You are really asking for one hell of a money pit with all that.

Figure to get a good setup for the power your asking for, your going to look at nearly 10grand in just the motor, another 5 into the trans, then your adders. Turbo's, blower, intercoolers, piping, engine management system and so on.

Are u going to have the engine balanced and blue printed? Crank knife edged? I mean there are a lot of things here that you seem to overlook. But my main question is how do u plan to cool the engine with all that power being made? You will need a huge efficient radiator, and plenty of fans. How are u going to cool your trans? Do u plan to do a fill on the block? How do u plan to oil all this? Cause thats a ton of extra's I dont think you have really considered properly to be honest.

Fuel you may as well run strait alcohol on that kinda power. Why not just run a dry sump oil pan and call it a day with an external pump. Run a fuel cell and an A1000 fuel pump while your at it since your in tank pumps are not going to flow nearly enough volume of fuel to hit much above 700-800hp. Atleast they dont in a supra without going to a dual hanger and 2 255lph pumps.

It honestly sounds like you have some cool idea's that will get killed once the reality of things catches up to be completely honest. I mean your going to need very tight tolerences in order to make the power your asking reliably. And in building engines, I have stuck by a solid motto since day 1. Build for atleast 50% more HP than you plan to make. So if you are planning to stop at 700hp, build for 1050hp.