twin turbo small block questions

Gimme a minute, gotta go into work.

 

Don't take this the wrong way, but when it comes to speed being skilled and creative only goes so far. One thing you are not going to be making is internal engine parts, transmission parts, and rearend parts. Those are gonna have to be bought. Somehow.

When I put the statement above into the context of my experience with street/strip small block chevies, you don't have a 700hp budget. Realistically, even with dedication & creativity....at 450hp, your car is gonna be parked half the time due to breakage. You can dispute this anyway you like, but when you've walked further down the path, you'll understand what I mean.

Here's another secret that you'll never learn at 700hp. You can't be a street hero if your car ain't on the scene. 450hp, properly applied, will shut down almost anybody with street tires. If a rival shows up on the scene with 700hp, drag your feet for 3-4 weeks and don't race them right away. Because in 3 weeks they'll be broken and saving up $3500 to get the car back on the road. And you'll remain the street hero with your rep intact.

The other thing....if you're serious enough about going fast for cheap, that starfire is a poor choice. Losing weight is cheaper than adding power and you need a VERY strong ch***is to apply 700hp and stay in one lane. The cheapest way to go fast is probably something like a tubbed vega that you'll buy as a clapped-out ex drag car. That starfire is a boat and you're gonna have to make another 75-100 at the crank to compensate for giving the other guy a 750lb wieght advantage. When you look at the cost of HP, suddenly the non-traditional (lightweight) drag ch***is is the cheapest option to go fast.

good luck and race safe

 

put a 351 Windsor in it,they can handle up to 800+ hp.......oh wait SBC are gods gift to hotrods

 

Few years back i got in alittle street race with a buick grandnational. Im running a 383 with 450 hp 500ft pnds of torque in my 81 cutl***. His turbo 3.8 V6 chewed me up and spit me out. I took him for the first 60 ft after that all i saw was his tail lights. Sure you really want 1000hp?

 

Has anyone noticed that (with minor exceptions) "twin turbo" builds are all novices with no experience, no money, and no idea what they're doing?
A project that begins with a cool name just goes down-hill from there.

 

I had the same idea when I was building my blower motor... "I was planning on building mine on a budget of 3 to 4k"... I would recommend before you start and get your hopes up, double your expected expenditure! Here are a couple things off the top of my head to get you thinking...

Your heads are the weak link. However when it comes to boosting an engine, You need a superior oiling system before you can even think about a top end... You will need a set of low compression, reinforced ring groove, forged pistons. Aluminum heads will help avoid detonation. Stock rebuilt rods will be ok, as long as you watch your rpm. Get a solid steel crank $$$. You need a 114-116 lobe separation flat tappet hydraulic cam, a roller cam may work but $$$$ for a blower grind.

The list goes on...again spend the money upfront to do it right.

 

honestly you probably need to triple your budget just for the engine minus the induction. Turbos and smallblocks are a salty endeavor and in no way am I telling you not to do it, but it is quite a bit more invooved than the chepest parts you can find on e-bay. A good forged crank and bearings w/o rods will come close to the $1,000 mark. The 383 is NOT a rpm monster like the 355 w/ a 6 inch rod can be. turbos like rpm. honestly if you are lookign at 700 hp maybe you should consider a big block with natural asperation. it will still be over 4,000 bucks, but not as bad to get 700 hp out of 454+ cubic inches as it is to get it out of a SBC.

 

not true. Im a GM guy, but that windsor is a bad mo-fo.

 

LOL, thanks for my morning giggle

Yeah, pretty much anything past the 450 RWHP mark on a stock unsupported Ford Windsor results in this:




But thanks for the troll anyway.

 

Ok, those in this post that HAVE built a turbo'd setup stand up. Those that HAVE NOT built a turbo'd setup, sit down. Take note here Original poster!
Everyone has an opinion of what works, but who has ACTUALLY done it? I know some has, but not everyone here. The "site" that got me to believing that it could be done with a budget (not 1000hp tho!) was toohighpsi.com, And the budget Capri car he did.

 

Ok, let me cleave through the mud here. I think everyone new to turbos wants that magical 1K, a lofty goal indeed but it is attainable. I think realistically you are going to spend about 3-4K from where you are starting and end up making north of 750 HP, but...

The first money you should spend is on the Corky Bell book: Maximum Boost. Old but still a wealth of information and it will set your head straight. Not to offend those that are trying to help here, but while your advice may be sound to your train of thought it may not apply here.

Your block can be a reasonable foundation if it checks out. Stroker kits are not an anathema to turbos as suggested, in fact it displacement will help you in building a 1K engine on a budget. Why? First off, turbos work on air flow, period. The more air you shove through the turbine the more air you can shove through the compressor, it really is that simple! The other half of this equation is most turbo engines are not generally high revving engines, unless you have a small displacement that is.

You don't need turbo pistons, but they are nice. Forged if you can swing the buck.

Eagle cranks are cheap

GM fast burn heads with some port work could be a good alternative to AFR, Trick Flow or Brodix heads. Look into some used race car stuff, a workable pair of sprint car or big oval track heads might surprise you.

Cams, turbo grind cams work but are usually pretty conservative, I highly recommend a custom grind cam to suit your needs. I use www.cammotion.com out of Baton Rouge.

Motor plates! Do not rely on stock side engine mounts, they will pull right out of the block at these power levels.

Ignition controlled by something like the MSD digital 7

Turbo, well if budget is really the issue you may want to consider something like the Borg S400 series single. Several race shops are modifying these to support stupid amounts of power for pretty reasonable money. http://www.bullseyepower.com/home.asp has an S480 for around $900.

Getting into these power levels and wanting your turbo to live, you need a good waste gate and blow-off valve. I have use the Tial stuff because it's American Made, but I hear a few guys have successfully used the OX stuff which is a copy of the Tial but much less $.

You don't need a ton of exotic gear to make this work. In fact 3.0 gears and an TH400 trans built for the purpose will surprise you on how drivable it really is!

 

This question is so much more basic than you make it out to be.

Regardless of induction........

700hp worth of fuel consumption is 700hp of fuel consumption. Carbureted, EFI, blown, NOS, or N/A. Same with crankshaft and block strength. Same with ch***is, transmission, rear axle and rear suspension. Especially rear suspension. It doesn't matter what kind of mechanism or mixer is cramming 700hp worth of fuel and air into the cylinders. Your hard parts have to withstand 700 hp worth of bang.

There is always somebody out there that defied all the rules, exceeds the limits of all their parts by 200hp and somehow managed to do it for half of what mortals will pay.

If the plan for building a car counts on you being that guy.....your ****'s gonna be dusty and broken. All the time. Because "that guy" is as much lucky as good. Anybody that's been around fast stuff knows that counting on luck is expensive. Real expensive.

Oh yeah, we totally forgot one cost category.....the tune. All the guys that defy gravity have a TON of dyno time or a TON of data logging equipment and track runs that are more scientific than fun. When a guy only adds up his hard parts and neglects to mention over $2k in data acquistion it's kinda misleading.

good luck and race safe!

 

^^^^

Exactly, Shifty!

that's why it is important to listen to those that have been down this road before, get your **** over to www.theturboforums.com and leave the HAMB for traditional hot rods!

 

real garretts for cheap: www.vsracing.net

i've done a few turbo setups and am planning a turbo for the 5.0 efi motor i just swapped into my '71 f-100. definitely not going twin turbo as i don't need that kind of power. i plan on using the stock bottom end so i'm realistically looking for about 450 whp. a single t4, intercooled, with less than a bar of boost should make this happen. my plan calls for some used aluminum heads, a ford racing roller cam, and a cobra intake which can all be found used and for cheap. you can use shorty headers flipped around pointing forward for a turbo setup. all of this with a plug-n-play aem ems and i'm on my way to 500 hp.

imo you're never going to make 1000 hp on a blow through carb setup. never. you could very easily double your base horse power level with like 10-12 psi of boost. take a decent small block that makes 300 hp, throw some boost at it, and you'll have an easy 500-550 whp which is more than you'll ever need for a street car. plus you'll have a **** load of torque to boot which is what you actually really need. the torque will be almost instantaneous whereas the power is on the top end. torque is what makes street driving fun.

anyways, good luck and keep doing lots of research.

 

I am in agreeance with what you have said. But my point was that he needs to do a TON more research, that's why I said theturboforums earlier. There is always just too many people on a forum that is not dedicated to the question At hand that just muddies the water with opionions on theories and no experience (myself included sometimes). 500-700 hp is fairly attainable with normal parts (ie. A budget), but more is not really realistic IMO. Dooable? Yes, but realistic? No. Good parts won't make a bit of difference if he (or anyone) doesn't know about making a turbo car run, they will be on the ground just the same IMO.

 

Dammit.

Now you tell me...


( I'll be fine, it will be way under 450 )

 

Alex, just get the valley girdles and main cap girdles and you will do fine..

My point is not to discourage this guys behavior, I know he won't make his goal of 1K HP for sub 5K investment and that isn't the point. Too many guys armchair quarterback the **** out of these posts and no one ever learns. I would much rather see this guy stick a pair of T40Bs or some hybrids on some cobbled exhaust on a stocker 350 and make an honest 400+ FW/HP. It's a much better situation than telling him he can't.

 

I really appreciate all of the responses, especially from those of you that have turbo setups gonmad (I love your camaro) and Elpolacko (I love your truck) in particular. I think that I am going to put this project on hold for a little while so I can save up some more money to buy better parts. As far as the Starfire goes Shifty Shifterton I thing you are missing the point entirely. I am trying to resurect this very rare car (that I like very much) that I saved from being crushed at a junkyard. If I wanted a vega dont you think I would have bought one. As far as the drivetrain goes I already have a built ford 9" from a past project, and a race built turbo 400. I am currently fabricating a 4 link suspension for the starfire. It is a full frame vehicle so there is no need for subframe connectors. I do not intend on flogging this car on a regular basis, so I think that the engine will last for a long time if I am easy on it. I just want to have the power there incase I need it. If the engine blows then so be it. It won't be my first, and it won't be my last. I won't let peoples negative comments desuade me from doing this project. If I have problems with it, there are plenty of knowledgable and friendly people out there to help me out. Now I'm off to the turbo forums to do some research. Thanks.
-Greg

 

Wha?

Why make a statement like this? I hope you are not saying it isn't possible to do.

 

I finished my post a little early....sorry, don't get me wrong, forced induction is sweet. I would hate to see you sink your hard earned money into a project, have it run for a bit and then **** out...(which it may or may not). Nothing is ever perfect, but do your research and try and make it as best you can the first time, even if it takes a bit longer. If you have any specific questions, I have build a couple blower motors and 2 single turbo motors with success.

 

If you're building 700 horsepower "in case you need it" then you really have no idea what kind of compromises are inherent to a 700 horsepower vehicle. Sorry man, that's just how it is. 700 horsepower vehicles are not "saved" by any means. More like ticking bombs. That's their appeal. You gonna put a full cage in this beast? 700 will kink that stock frame in a hurry

Good luck with your ride, and don't race pro street vegas with 500 horse.

 

Yes there are a few people who check this site out that have some turbo experience. You have a very big learning curve ahead. Have Fun!

Here's my 368" small block. Made 1407 hp on 18 lbs boost




The engine above made this the 1st production bodied car to exceed and set a record over 300 mph at the Bonneville Salt Flats.


This is a Nissan VQ35 single turbo. 1000 hp


Here is an early draw through I did back in the mid '80's. made 880 hp out of 300"s


Hre's a single turbo 300" small block that made 1250 hp.


This is a Vortec blower on a Ford engine. A little different but not much.


Lastly a twin turbo 509" big block chevy on PROPANE! made 750 hp at 3500 rpm and 1500+ at 7000.

 

Ooooohhhhh, that hp on a drawthru is nice! Hadn't seen that much with success on a drawthru!
I'd say you would be one to listen to!! Lol.

 

Dynoroom has sweet hardware!!

Greg don't let me discourage you and have fun building boost. You'll never go back!

 

yeah , those 500 horse vegas are a hand full.... first car i got to drive that was capable of pulling the wheels on the street.... can't imagine that ride with the 2 stages it had as well..... as a small comparison of the hp to quickness deal...1 of my customers had a drag car with a 18 degree 406 . made 720ish hp...went 9 teens in his 2300 car. take a trip over to yellowbullet...tons of cool turbo video post over there.

 

Oh I wish I had some photos of my 347 when it let loose. This block isnt nothing to what mine looked like when I sprayed 600 shot to it. It was completely in half (2 pieces), along with the Lunatti crank and aluminum rods going all over the place when they shot out of the bottom end. It was the most violent explosion I have ever felt from a motor, even the cam was in 3 pieces LOL.

I was running a 2 stage fogger set up on it and usually sprayed 2 off the line and 2 on the second stage but my buddy and I wanted to see what it felt like with all 600 hitting at once. It was fun while it lasted....

 

I admittedly do not have experience with a twin turbo small block. I have been working with turbo systems for over 15 years.
Anyone making the statement that 1k hp on carb's engines is unobtainable hasn't done the research. It's been done. I am in the high 800's on a single blow through application and damn near any hp goal can be met with enough money.
The budget is unrealistic. Possibly the best plan is to build the low compression engine NA and get the car driveable. Save for the turbo system until you are not compromising. $300 Ebay turbos will not live. You may have a whole new perspective on what you need for power once the car is driveable.

 

I don't exactly agree 100%. I made 620 HP with a bone stock 5.0 302 H.O. block, crank, rods, pistons, and E7 heads with the only work done to them being the EGR humps removed. I threw the engine together in my garage with no machine work other than a ball hone on a drill.

I figured out how to do turbos on my own with what little info was available back in 2000. I blew up a lot of stuff learning, but it was lots of fun, however I never cracked a block from the excessive HP on the windsor blocks that everyone talked about. I think that happens more because of the excessive stresses on the block coupled with something going wrong at the same time. I lost my hose to my Fuel Pressure Regulator one night doing some test runs up the highway from my house at 18 PSI and, of course, the fuel went away and I got a lean "pop" that took a huge chunk off the #8 piston and welded pieces of that to all the other pistons across the intake. It also cracked the cylinder wall, so that block was trashed. That is when I built the last motor in the garage. I ran 10's in it and made 620HP and with a 1:1 final drive ****** and 3.27 rear gears, I got 21 MPG driving home from the track so my friend could use my trailer after separating his intake trying to spray a Neon.

Get Corky Bell's book like mentioned before and also get Hugh McKinnes "Turbochargers" book too. Read a ton on the internet. Also check out the turbomustangs.com forums. Those guys have been doing this for a long time and there is tons of basic setup knowledge and info about blowthrough carbs and there is even chevy stuff there too.

Here is a website I made as I was doing my builds starting in 2000. I had tons of emails from people that referenced my site while trying to figure things out themselves before the bigger forums started discussing the black art of turbocharging. So maybe it will also help. http://turbostangtodd.com/.

This is a funny coincidence. I was thinking about building a model a using a 2.3L 4 cylinder and a turbo setup next, with the hood in place so no one would be able to see what is happening in there, but I Was going to shoot for about 400HP with it. No fenders, and hopefully a roadster body if I can locate one. Spoke wheels. Could be a fun car!

 

By the way, do not use the K&N "Carb Hat" that some people try to sell you out there. It does screw up the flow of air coming into the carb and things get metered all wierd.



Go for the ones that appear to have a smoother transition.

 

sorry to be so unspecific. he's never going to make 1000 hp with a blow through setup like he's describing or budgeted for. kna mean?