I am going to turbocharge my 2.8. It is brand new, not rebuilt but brand new, it has around 2500 miles on the engine, Compcams 260H camshaft with equal intake and exhaust duration, ported intake manifolds with work being done to remove the restriction from the intake neck, ported heads including intake and exhaust bowls, welded and ported stock exhaust manifolds but will be upgrading soon. Severe Duty felpro permatorque head gaskets.
I will get a bigger fuel pump and injectors Installing a boost gauge and AFR gauge I will be upgrading to a 7730 ECM with knock sensor Air to Water Intercooler (unless it turns out it is unnecessary) I will weld a bung for the oil return line into the oil pan I will get a 2 or 3 bar map sensor I will be doing a catch can system for the PCV I will monitor oil temps and get an oil cooler if temps are getting too hot once it is installed.
I will not be doing the tuning myself (At least that is the current plan) But I will be doing all the welding and fabrication myself. I am building a crossover currently from mandrel bent 1.5" 16 gauge steel exhaust pipe.
I am planning on using an external waste gate. I will probably have it dump to the atmosphere. I am planning on going top quality for the waste gate.
So for turbo sizing/ selection this is where I am lacking in knowledge. I have done a lot of research on everything else in the past year but I am still having trouble sizing my engine to match it up with the turbo maps. I hear a T3 is a good size for our cars. I have also been looking at K26 from a 944 turbo because it is a similar sized engine and it is factory watercooled.
Here are my goals:
I would like to get around 250 - 260 crank horsepower, so around 230 whp and I am estimating it will achieve this with around 10 - 12 pounds of boost. I feel that with an air to water intercooler if I can keep intake temps under 130 ish degrees I wont have to worry about melting my pistons. I would like the power to come on around 2600 rpms and I want to hit max boost at 6000 rpms.
I would like similar to stock 3800 hp. I am not doing a 3800 because I got an awesome deal on the engine parts and got almost new heads for 150, cam for 150, and the block and internals for only 300. I did all the work myself so I did not spend anything on labor. I have always wanted to turbocharge my Fiero and I am doing it a lot for the experience itself, I love designing and fabricating. I do not drive my car a ton, I drive it everyday but not very far, and I don't drive it that much when I am at school (which is most of the year). I would be very happy if 0-60 was under 6 seconds.
Did you mean wastegate dump to atmosphere? Or Blow Off Valve dump to atmosphere? The wastegate dumping exhaust to an open pipe will be LOUD.
Also, my T3 makes max boost in the 2000-3000 rpm range and up. It has an internal wastegate though. Max torque is in the 4500 rpm area so you really want to make max boost allot lower than 6000 rpm. The 2 bar map and related code will be fine for less than 15 psi. I am running code59 with a 3 bar map because I want more than 15psi once I change turbos.
Take a look at the Garrett app called BoostAdviser. Run all the numbers you want and then find the airflow needed to get those numbers at the specific rpm the engine will be operating. Then you can go find a turbo that matches what your engine will need. It's pretty straight forward. I want 100 hp per liter.
This is the best summary of the physics of turbo charging that I have ever seen. If you have any questions, post them.
To use the above info, you need to make some assumptions. The ones I made, which ended up being pretty good, was that it was beginning to boost at 2krpm, 4psi at 2500, 8psi at 3000...then wastegate action to hold it there. Also, I assumed a 85% VE (Volumetric efficiency) across the range.
The hp range you are shooting for is the high end of what can be expected with a 2.8 without modifications.
Having said that, I'm running a 3.4 at 12psi without one with no detonation, so with the right tuning who knows.
This allows you to calculate your air flow requirements, then size your compressor from that.
Some things to note, which I learned after a lot of reading. On the compressor size, the trim of the compressor, not the housing size is the determining factor in flow.
On the hot side, the housing is the determining factor in ultimate flow. In other words, you can only shove so much exhaust through a certain size hole.
I ended up with a EVO 8 turbo which is a good fit.
For your engine, the classic is a T3 with a 50 trim compressor, and a .63 turbine (hot side) housing.
You can do better with a hybrid T3/T4, with a bit more lag. Is this for street or strip? For street, you want your spool to be on the quicker side.
Street/ Autocross. And thanks for all the good information. Yea I was using that app on Garretts site but I wasn't sure if the values they were looking for were for pre or post boost. I did pre boost numbers and they recommended like 12 different turbos so it did not help that much. My engine is somewhat modified with the cam which has a much higher intake lift/duration than stock, like .38 to .44. Also everything is ported decently large, which probably hurt my NA power, but will be good with the turbo.
What cars have a T3? It would be nice to find a nice factory turbo in a junkyard and buy a rebuild kit. I know the thunderbird is a common one I see on the forum and I know convictedredneck used a K26 from a 944 in his turbo build
I said wastegate dump to atmosphere because I guess I did not know that you remain at max boost so long, I figured that at around 6000 rpms I would hit max boost and dump there right before I shift.
Blow off valve will obviously have a duck call attached to it
Just remember, Evo turbos are twin scroll. The 03-04 cars have a 9.8 hot side, the 05-06 have the bigger 10.5 hot side. Nobody in the Evo world wants the early turbo so you can usually get them pretty cheap. Also, screamer pipes seem like a good idea, but they get old, really quick! Trust me on that one!
[This message has been edited by BV MotorSports (edited 06-26-2013).]
Just remember, Evo turbos are twin scroll. The 03-04 cars have a 9.8 hot side, the 05-06 have the bigger 10.5 hot side. Nobody in the Evo world wants the early turbo so you can usually get them pretty cheap. Also, screamer pipes seem like a good idea, but they get old, really quick! Trust me on that one!
What size turbo does the evo have? I just checked out ebay and there is tons of them for sale for like 250 bucks with the 9.8 hot side
I cannot find it... because of the twin scroll, the AR is equivalent to .43 is all I got so far, but if it works for the 3.4 then would it be a little to big for a 2.8?
Because it is twin scroll would I run each part of the Y pipe separately into each side of the hot side housing because that makes sense.
[This message has been edited by zkhennings (edited 06-26-2013).]
Ok, on the evo. turbo: I have the TD05HR-16G6-9T (9.8cm2). The map is very much the same as the 50trim T4, and the 9CM2 turbine is like a A/R of .65.
I ground off a little poin and now it's 360 clockable. Easy to do, you just need a big set of C clip pliers to seperate the compressor section. The hot side is v-banded.
I welded the internal wastegate shut and used an external mostly because it didn't come with the actuator. Plus, I wanted an external wastegate so I could run a big one, because initially I had planned to run low boost (Lower the boost the bigger the wastegate).
You'll find a 50trim T3 on 79+ mustangs, Thunderbirds and Merkur XR4Ti's with a .48 hot side, they will all have the standard ford 5-bolt internal wastegate. the 84-88 Nissan 300ZX will have a 60 trim T3 with the .63 hot side a,d the same 5-bolt hot side housing but the wastgate it self is goofy, but the nissan gate can be swapped with a ford 5 bold internal wastgate. Sabb 9000's use T3's as well, I have seen them with .48 & .63 hot sides and both 50 and 60 trim cold sides.
In my experience a T3 with the .48 hot side will be too small for your goals, on 3.0L 300zx's the .63 hot side is a restriction but it works well in the range you set your goals at.
You're aiming kind of high for a 2.8L and I say that only because I eventually broke a ring land on the very old design stock 2.8L piston running a conservative 7-8 psi of boost pressure after about 2-3 years. If you have new old stock cast pistons instead of modern hypereutectic pistons. 10-12 psi will probably take its toll before long. It has been many years since I've seen one but I recall a substantial gap somewhere in the area of the casting as it relates to the ring land that results in less support than what is seen in the OE hypereutectic pistons.
What would the evo 8 turbo be like on a 2.8? And specifically when I make max boost? Remember it is not a stock engine (cam and ported heads and manifolds) and I doubt I will stay with the stock intake manifold and headers for long and I will probably get some 1.6 ratio rockers as well. So if I can make max boost by the time I make max hp (around 5000 with my cam) then I will go with this turbo. It seems awesome after reading up on it because of the materials it spools extra fast and the twin scroll works perfectly with the custom Y pipe and our firing order.
You're aiming kind of high for a 2.8L and I say that only because I eventually broke a ring land on the very old design stock 2.8L piston running a conservative 7-8 psi of boost pressure after about 2-3 years. If you have new old stock cast pistons instead of modern hypereutectic pistons. 10-12 psi will probably take its toll before long. It has been many years since I've seen one but I recall a substantial gap somewhere in the area of the casting as it relates to the ring land that results in less support than what is seen in the OE hypereutectic pistons.
These are not hyper-eutectic but they are brand new like the rest of the engine so they may reflect a new design with the ring land. Regardless if that happens I will buy some new forged rods and pistons and turn the boost up so ill have something to look forward to. I do all the work on my car myself, so if I had engine problems I could fix it within a weekend if I had the parts. I definitely will not keep the setup the way it is for over a year. On the other hand, there are people using the design one system that have run 10 pounds for years on the stock internals, but I totally accept the possibility things may go wrong. I haven't had an engine in my car longer than a year since I got it I am always improving it, it is my hobby (And yes I mean 3 totally different engine have been in my car since I bought it in 2010)
[This message has been edited by zkhennings (edited 06-26-2013).]
I'm a bit biased but I feel like the K26 is a good match for the 2.8, especially with the engine mods you have. From a porsche forum:
quote
From the information and mesuring i did last year. A k26 is equivalent to a T3/50 trim First by the actual size of the compressor wheel. Second by comparing the maps
Just search google for "k26/6 turbo specs" and there's a host of good information on them, including compressor maps (which admittedly I don't understand although researching them)
A/W intercooler is definitely the way to go, as is water/meth injection. Running 93 octane and the water/meth on, I've gone to 14psi with zero knock. That's NOT saying it's good for the motor in the long run, but people's general misconception that these motors grenade anywhere over 7psi is incorrect. I run 12 psi consistently, with water/meth coming on at about 6psi and have a couple thousand miles on the turbo system. In support of the naysayers though, I have no expectations of this setup lasting like a factory turbo'ed vehicle would, but hey, let's face it...we're over DOUBLING the stock WHP.
As for the wastegate to atmosphere...that's what I did and I personally love it. Sure it's a bit loud, but cruising around town you're not dumping pressure off every time you leave a stoplight. And when it is dumping...I just think it sounds mean! The BOV on the other hand I'm looking at recirculating. I already replaced the "horn" outlet on it with a straight piece to quiet it down. Plus, recirculating supposedly helps keep the turbo spooled.
I know you've seen my build thread (considering you were the last post in it besides mine ) but I definitely didn't go into very much detail throughout the thread. I've done pretty much everything you mentioned...water/meth, a/w intercooler, oil cooler, water cooling the turbo, 7730...so if you have any detailed questions shoot me a PM or 10!
What cam did you use? I hope it doesn't have a lot of overlap, I also wouldn't dwell on replacing things like the intake manifold or stuff like that in the future, you would get more power out of 1 more PSI that any kind of manifold swap.
also when it comes to ring gaps, you can probably ask 15 engine builders and get 15 different answers. a lot of engines that have ring land issues when you start adding boost, the Nissa KA family in particular, live LONG healthy lives with the 2 ring opened up significantly more than the top ring, the basic theory is that this process will allow excess pressure to escape from between the rings preventing a failure.
Goggle "Big Bang Theory" Its a Hot rod magazine article about a stock bottom 4.8L LSx motor that made 1200 HP
I think the Evo turbo is the way to go. The twin scroll design will make it spool very quickly. They are tough turbos and can make great power. On my 2005 EVO with the 10.5 hotside, it made 350whp @ 21psi. No power adders & pump gas. There are tons of the 9.8's, they are cheap and easy to rebuild.
The compressor may be a bit big for your application, but I don't think it will get into the surge zone.
The spool is really quick. There is more complexity with the twin scroll design. It feeds nicely off each bank of the v6 though.
It has lots of capacity...there was a guy with a 3400 (not the tdc) who used it. It was an old blog entry I read at the $59 forum. He didn't express any concerns with the size fo the turbo.
The manifold etc will not help a whole lot; it will not change your air flow requirements much. That is due to the poor flowing heads we have.
Anyway, no need to worry about turbo sizing changes due to the minor mods you have.
My engine is a bit 'loose' so maybe that's helping the land failure stuff...not sure.
Materials wise there were two different types of metal used...standard stuff and the super crazy inconel...
Not all of them are inconel, mine isn't. It's a well built turbo though.
Max boost is one of those things. It will build as a result of exhaust power. So, if your max boost is 6psi, you'll hit that a 3k. If it's 12psi, you'll hit that later on.
It's a balance though, because as your boost is building, so is your turbine backpressure.
The only way to tell how it will act is to try it. For $200 it's hard to go wrong. It won't be too small, I can guarantee that.
Read all you can. Good books way back to the 1960's. The guys are right suggesting double the ?125 hp? is more prudent and will take 15 lbs. That is a lot and can cause head sealing problems. Most mfgrs seem to stay 8-10 lbs. Your work on the porting may be unecessay as an advantage of pressurized charge is that it forgives a lot Big exhaust required. Work on the low end lag with the AR of the units available (aspect ratio), or you may loose low end big time. Finally, it's been a while for me but get water cooled turbine bearing and really be careful of the exhaust piping to the turbo-CRACKS.!
I think I am going to go for it and just buy one, the K26 does look good too but it is way more expensive.
Slowbuild, when do you hit max boost and how high is your max boost with the 3.4? I figure it will be kind of close to the 2.8 as they share the same heads and they can only flow so much at the same (similar) pressures.
I will probably have lots of questions to ask you Convicted, I do not think I will be running DIS though.
I am not tearing apart the engine now to change my ring gaps, both gaps are only a tiny bit over 0.010 inches I think it will be fine.
The cam specs can be found here I love the lopey idle
Read all you can. Good books way back to the 1960's. The guys are right suggesting double the ?125 hp? is more prudent and will take 15 lbs. That is a lot and can cause head sealing problems. Most mfgrs seem to stay 8-10 lbs. Your work on the porting may be unecessay as an advantage of pressurized charge is that it forgives a lot Big exhaust required. Work on the low end lag with the AR of the units available (aspect ratio), or you may loose low end big time. Finally, it's been a while for me but get water cooled turbine bearing and really be careful of the exhaust piping to the turbo-CRACKS.!
I am sure the port work will help. I have Severe Duty Felpro head gaskets which are awesome, way way tougher than any of the head gaskets I have ever seen. Even has rubber o-ring type seals around all water passages. I also torqued my head bolts to around 90ftlbs which I have found out is pretty high but good for sealing. I ordered a flex 1.5" exhaust piece from summit to put in the long side of the crossover. Yea the main thing I am worried about with the evo turbo is the lag, but the evo has a 2.0 liter engine and it spools fine, and I am sure NA that 2.0 liter is the same or worse than our 2.8s. The evo turbo is water cooled, but I am not sure if the bearing is watercooled as well. It is a pretty advanced turbo. I probably will not surpass 10 psi but then again I probably will when it is in my car!
I used 1.5" sched 40 steel pipe and weld 'els' ("Steam pipe") and tiged it to the ss expansion fittings and fiero manifolds with ss filler (312 I think, can't remember for sure). Anyway, it's crack free so far. SS would be better but $$$$.
Also, I used 'titanium' DEI header wrap with the silicone spray (black) to keep the heat down, and in the pipes. Seems to work well.
Note: the only challenging thing about the turbo is the way the exhaust outlet is at an angle. I blocked off the internal wastegate opening so the post turbo 'down pipe' is just a 2.5" standard round pipe.
Note: I ended up plumbing the turbo and wastegate together, and a straight pipe out. There is no muffler. It's a bit loud, but not too bad. Nice low note at idle. The turbo kills a lot of sound. I had a ricer flow through muffler on it, but it fell off ( ha ha) and I just left it off.
Chay
[This message has been edited by Slowbuild (edited 06-26-2013).]
The 4G63 evo moves a LOT of air. I chose it based on the stock 300 hp, 14psi and about 6krpm. In other words, it flows about the same as my 3.4, or maybe a little more. I think it will be fine on a 2.8. It'll be a kick in the pants when it spools.
The center section has a oil restrictor in the housing. They use banjo fittings to feed/return the oil. Cooling water is the same. Both oil and water connections are on the center section, so the bearing will see some cooling from the center section being cooler. There are just 2 passages in the center section basically.
Nice. Well I do not have enough money to finish a turbo setup this summer I think, I am close budget wise and will cut into my school year spending money, so if I win this turbo then it is fate and I'm going for it, if I don't I will hold off for a little.
Is there aftermarket springs for the internal wastegate? Because I think mechanically it is around 12, and then the evos have a boost controller that pushes boost to 19 PSI stock
[This message has been edited by zkhennings (edited 06-27-2013).]
Do the injectors from the 3800s work in our cars? I only ask because there are tons of 3800 owners that have upgraded their injectors on this forum vs buying them from a mustang off ebay.
Down a bit from the top....there are TONS of injectors you can use.
The critical measurements are measured from the groove where the clip hold the top of the injector into the rail.
The groove to the bottom end of the injector should be 2.42 inches.
The groove to top of the injector needs to be .35" or longer (stock is about .44") this is to seal in the fuel rail properly.
I think pretty much all the injectors from the same era are the same diameter.
There are hi/low z injectors too, but I didn't get into that too much. I'm not sure which are which. I can tell you the '7730 has no problem with the lt injectors.
I think I am basically doing the PPG mod to my fieros upper intake to shorten runners and increase plenum volume (After looking at those nice velocity stacks you made)
Someone once told me that you also have to increase your fuel pressure by the same amount you are boosting your engine so that they can still flow at the expected rate since that pressure becomes a resistance to the injector's fuel pressure.
If stock injectors are 15#, then to double the HP, you'd need double the fuel and hence 30# injectors to be safe.
[This message has been edited by lou_dias (edited 06-27-2013).]
12psi will not double your hp output. Probably around 70% or so. Still a big chunk, but not double.
The reasoning is this:
1) Atmospheric is 14.7 or so. 12/14.7 = 81% to start 2) The charge will be hotter (less dense) than atmospheric, so you can't directly relate pressures to oxygen content 3) The timing will need to backed off somewhat avoid detonation
If I did the intake again, i'd use the same runners, but make a single big throttle body instead of the twin setup. The twin looks cool, but is a hassle with linkages etc. Also, the charged air piping is twice the hassle, two couplers, etc etc.
As far as fuel pressure rise for turbos, it is really about how much fuel you deliver, period. It is true that if you are trying to inject into an increasing pressure stream, less and less will get in there, per ms of injecting time. But, we can just tune the injector to stay open longer, up to a point, which should be about 80% duty cycle max.
My 24lbs can handle the fueling required for the 3.4 at 12psi, at 12:1 ratio. Hope that helps.
Also since the manifold is hooked up with a vacuum line to the fuel pressure regulator, and under vacuum it lowers fuel pressure, then I assume when making boost it raises the fuel pressure. At what point will like a walbro fuel pump say "no" to more pressure?
) but I definitely didn't go into very much detail throughout the thread. I've done pretty much everything you mentioned...water/meth, a/w intercooler, oil cooler, water cooling the turbo, 7730...so if you have any detailed questions shoot me a PM or 10!
