Hello all, ill be pullin my motor out and replanting it in my new shell, figured since i was doing this i would go ahead and turbo it. My downfall is i know nothing about turbos and would like to build a system that wont blow up my engine. jere are my specs

Coast high 393 small block with 195 72cc AFR heads, 10.25 compression ratio comp cams roller rockers and lifters and a custom cam (forgot the specs on it) i would like to get to 700hp if possible

I would like to build this turbo with ebay parts on the things i can get away with, i have been told that i need atleast a 80mm turbo, any recomendations on a good trubo that wont cost me an arm and a leg, i have looked thru here and cant find a list of all the parts needed to build this set up, can anyone help me with that aswell??? I plan on building this over the next couple of months. Thanks guys

 

you have allot of compression what fuel are you going to run?

 

93 octane

 

I'm not sure how much boost you will be able to run you are close to the limits of pump gas as it is. There are options like meth injection to cool the combustion chamber. But think realist. Don't know your budget here but if you have your heart set on a turbo or TT I would be shopping for less compression on the pistons.

 

Can you school me on compression and what ratio is the best for turbos, as far as budget I'm not trying to break the bank but also don't want anything that will blow the motor

 

After doing some reading looks like I'll have to swap to a reverse dome piston to bring the compression ratio down to mid - high 8's, at that ratio do you think it's doable??

 

I was running 10.75:1 on E85, no problems at all till I leaned it out and butted the rings, (not the fuel's fault, nor the compression), but as far as detonation, no problem at all. Is E85 available to you locally? I have to drive 24 miles to get mine, but since it's a drag only car (for now), that's fine, I usually get like 35 gallons at a time, 2 15 gallon barrels and a fiver. The 2 15s are easier to handle than a single 55, I just need one more to make it just right.

 

E85 is not that far from me, car will be a weekend car only for me

 

I'd sit back and look realistically at what you have to spend. It's like this, we don't call turbo car's jack stand hell for a reason. There is quite a bit that go into them especially if you don't know anything about them. Like Rick suggested with that compression I'd go E85. But understand you'll have to convert for it as well. I don't know your mechanical skills of what you do and don't know so I don't know if that's a possibility for you. As far as the other route suggested with the meth injection, it's doable but you have to keep an eye on fluid levels and check every time before going out... but definitely a good option. So I guess before any of us go further, tell us your budget and realistic expectations... because you DO GET WHAT YOU PAY FOR. As some of the wise members here say..... Cheap.... Fast.... Reliable.... Pick 2... they = the 3rd. Reliable and cheap, won't be fast, fast and reliable won't be cheap.. and cheap and fast it won't be reliable....

 

My budget would have to be under 4-5 k total, how possibe is that?? I would like to get to atleast 700hp, as far as mechanical experiemce i have some and could do all the instalation but as far as having to machine anything i would take it to a local shop. Im looking into the meth injection i would have to read all about that. When i originally built my motor i had planned for it to be strickly motor and power, but like always we end up wanting more hense why the high compression ratio as is.

So here are the 3 options so far that i have

1) new pistons which should bring my compression down to under 9 then building a turbo for it
2) meth injection (ill have to really become an expert on this and how everything works since i know less about this than i do turbos)
3) e85

 

Good advise ^^^ . A great idea for you is to get a book on turbo charging and read it check your libary or go out spend the $20. If you read it you will have a better understanding of what you need and need to do to build a system. "Street Turbocharging" is good so is "Maximum Boost" by Corkey Bell. Corkey Bells book is easy to follow and seems less technical then the other. Other things to consider do you weld or own a welder? Fabrication are you capable or be paying out. At least if read a book you have the proper information not from some one in a forum on a subject you know nothing about to able to judge if the info is good. If you can't spend money or visit a library to get that info you either will pay to have it done big bucks . Have a friend that can do it for you or be going into it blind with faith and guess work. I have built cars for over 20 years and am just about to get serious into turbo charging. I am doing my homework now to save $$ and aggravation down the road. It's not hard for a project like this to easily get more expensive and time consuming then one thought.

 

So i just read up on thr meth injection, seems like a reasonable option and since its cools the engine and sort of cleans it i might be leaning toward this

 

Yes i have someone that will come weld for me, im about to pick up aa welder and start to learn to weld but will not be welding any of my turbo system due to lack of experience, i came here because i was recommended this site by a friend and said there were alot of experienced turbo people on here, of course i will be doing my research before buyin anything but i just wanted a kick in the right direction

 

Meth injection cools the combustion chamber a cooler combustion chamber reduces chance for detonation. It does not effect compression ratios per say as much acts like an alternative to race gas or a high octane gas. Allot of good info here and allot good advise to be had.

 

also any chance you can dig up cam specs. Is your cam a high duration with allot of overlap? This effects things also. Are you running efi or a blow through. The best start for good advise is give a complete rundown of all you know about your engine trans and rear all will be effected also the honest use of the vehicle. All this stuff is important to give good accurate answers and the more accurate and more info in the more accurate and more info out.

 

I will try and dig up the specs on my cam, i had it custom built from a guy in austin and lost the spec card, ii have a efi 92gt with tko600 transmission ans 3:73 gears. Let me look thru old emails to see if i can dig up the cam specs

 

So i found an old email my cam guy sent me
Intake Opens 40 BTDC *Intake Closes 66 ABDC (All of this with intake centerline at 102 ATDC)


Exhaust Opens 79 BBDC Exhaust Closes 35 ATDC (Exhaust centerline will be 114 when intake is 102)



Intake lash hot is .014 *(Cold lash should be adjusted .008 to .009 for Alum head)

Exhaust lash hot is .020 (Cold lash should be adjusted .015 for Alum head. You can cold lash it at .020 if you wish, for more bottom end. However, doing so will make considerable valve train noise at operating temperature.)



Lobe lift Intake: .427... *This is 683 gross lift before lash and with 1.6 rocker arms.

Lobe Lift exhaust: 427.. " * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * "


Advertised Intake Duration at .020 tappet lift: 282. It's 286 at lash point

Advertised Exhaust Duration at .020 tappet lift is 294.

 

Just spit balling and not trying to take you from the turbo world, but with what you want, and expectations and it only being a weekend warrior with your compression level where it's at, have you considered Nitrous? ** ducking from the members **.... lol With a small shot from what it sounds like you have with your goal expectations, very easy to hit with what you have there. Only issue is, Nitrous is not forgiving... small enough shot will let you get away with a screw up or two on tuning and not eat your motor, but the bigger you go, the bigger the bang if its not dead nuts. But it's the cheapest option.......

Or, as suggested and your original route, Turbo, with 4-5 grand should be plenty easy enough, Hell you don't even have to break the bank, Get you a GT45 will be plenty to put you in that power range, you'll just need to make sure you have boost referenced regulator, a blow off valve, and waste gate, IC would be recommended especially given your compression already, if your not running E85, she's gonna be a little warm.... and if your looking to save money Hanger 18 mod that is listed here under the carb lounge will get you squared away its very simple and straight forward, for what your wanting will be perfect honestly IMO. But as far as plumbing, IC, Turbo if you go GT45 WG, BOV, I'd say your looking at around 2-2500K maybe a little North, but most important, is MAKE SURE YOU HAVE MEANS TO DELIVER FUEL, its better to make a system to big with aspiration to grow, than to be just enough or lacking and cause catastrophic failure, or have to buy shit all over again, there isn't nothing more annoying than that. You can always REGULATE DOWN, on too much, but can't make more with not enough know what I mean? And a wide band is a ABSOLUTE MUST, you need to see what that motor is doing, so you know if your running lean or not, its a key tuning component and making sure that motor lives a long happy life. We'll talk about timing and everything the further down the line you get in the build or just search the forums there is a TON of info here. Don't be afraid to ask questions, even if they been repeated a million times.... but search button is your best friend. Also, if you were building for high HP NA motor you might have a shorter gear in it, **numerically higher** like possibly a 4:10 etc... Turbo's like load, higher gears *numerically lower* make them build boost much faster, so running a 3:27-3:55 is pretty much in the sweet spot. You'll get good MPG, be in the boost fast, and be able to cruise highway and stuff no issues if you wanted, or just around town. When a turbo car is running right there isn't anything sweeter, but until it runs right........ lol You may hate life... lol But don't let that discourage you, it's trial and error just learn from others mistakes or your own. Listen to the gear heads but take some advice with a grain of salt if your questioning it in your own mind there is likely a reason, but all and all, really no bad misinformation on here, and if there is, we're quick to correct each other... lol


I should have read all the way down, I see you have a 3:73 with TKO, you should be fine... I love stick shift and turbo's... SOOOOOO FUN... lol And your gonna be really loud and noticeable whether that be a good thing or bad thing is on you...

 

Anyone know how far after the turbo is a good distance to place you wide band safely

 

My advice is to find some similar combos in the builds thread section and read, read, read. Most of the guys here are pretty good about posting the details, ups, and downs of turbocharging.

As far as the $$$ goes, I started with a $75 engine, an S475, headers, Wastegate, and BOV that I already had, and I'm rapidly closing in on having spent $3k on my setup doing all the work myself and trying to keep costs down, so be ready, it can get expensive fast.