The-Plethora Posted February 21, 2011 Share Posted February 21, 2011 Sorry for the very vague title but couldn't think of anything more accurate, mods rename if you can think of anything. I had the car to AFR and they were good enough to see me at fairly short notice on Saturday and fix several issues, fit the FCD and dyno run, Matt you still need to call me if you get your credit card reader sorted Brilliant work as usual from the guys and I can't recommend them enough. My question comes from the dyno run. As mentioned the guys fitted the FCD and I had lofty expectations of getting near 400bhp out of what should now be a full BPU car. It ended up at 372, whilst not exactly slow I of course would have prefferred it to be higher (mainly to annoy another guy in the office I work with who is into VR4s ) As you can see from the results it reaches bang on 1.2 bar and drops to 1 bar shortly afterwards... AFR checked the VSVs over which all seem to be opening fine and everything points towards something restrictive at the exhaust side. I currently have a custom made stainless steel exhaust, both whifbitz decats and restrictor ring. I went for the exhaust as although not as fancy as a nurspec which I would like it is a lot cheaper and should hold up better over the years being stainless steel. From memory the pipework for the custom exhaust was 3 inch. From the BPU link I see you need an aftermarket exhaust but is this still too restrictive? It does have a restrictor ring in still which I am happy to remove and hack away at but how do I ensure that the turbos are not overspeeding when I do? is my only option a second dyno run? or can I cut the ring, lower the boost controller instead? I'm guessing somewhere there must be a way of reading the bar preassure going through? Still a noob at much of this stuff. If anyone has any other ideas or suggestions I would be very greatful. I don't want to bin my 6 month old full stainless exhaust for a few extra BHP, but will I? yeah probably if it comes down to it Top points to the AFR guys for all they did in the short time they had and for John's one man comedy show on the phone to the guy with the cosworth Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 21, 2011 Share Posted February 21, 2011 372BHP is not bad for BPU, i think there is a lot of talk bandied about about getting 400BHP from BPU, but in reality its pretty rare, and most of the ones that are, have been run on rather unreliable RRs, its possible you may gain a little more buy changing the exhaust, but will the expenditure be worth it? Quote Link to comment Share on other sites More sharing options...
Scott Posted February 21, 2011 Share Posted February 21, 2011 Get a boost controller. 1.0bar is a good figure to get from a restrictor ring, everyone getting decent figures from their BPU cars will be running boost control of some sort. Quote Link to comment Share on other sites More sharing options...
The-Plethora Posted February 21, 2011 Author Share Posted February 21, 2011 Oh yeah its got a BC, HKS EVC IV I believe and it's been setup by the guys so I don't doubt their handywork. Quote Link to comment Share on other sites More sharing options...
Josh Posted February 21, 2011 Share Posted February 21, 2011 Have you got a boost gauge? That's a good way to keep an eye on the boost. You can then widen the restrictor ring and make sure the boost isn't going too high. Quote Link to comment Share on other sites More sharing options...
Scott Posted February 21, 2011 Share Posted February 21, 2011 Oh yeah its got a BC, HKS EVC IV I believe and it's been setup by the guys so I don't doubt their handywork. If it isn't making 1.2bar with a boost controller then it isn't set up correctly, either that or there are major problems with your turbo's/intercooler system. It doesn't matter how restrictive your exhaust is (within reason, even stock will see 1.2bar with slightly elevated EGTs) a boost controller will always force the increase in boost pressure by keeping the wastegate closed. Quote Link to comment Share on other sites More sharing options...
dude Posted February 22, 2011 Share Posted February 22, 2011 If it isn't making 1.2bar with a boost controller then it isn't set up correctly, either that or there are major problems with your turbo's/intercooler system. It doesn't matter how restrictive your exhaust is (within reason, even stock will see 1.2bar with slightly elevated EGTs) a boost controller will always force the increase in boost pressure by keeping the wastegate closed. Don't agree with that, in this case all actuators etc are working ok and the BC is set as aggressive as poss its just not holding the boost, most BC's spike then hold the lower boost fine, if this one spiked at 1.4 it may well hold 1.2. If you don't run a restrictor then the boost would stay constant. Quote Link to comment Share on other sites More sharing options...
The-Plethora Posted February 22, 2011 Author Share Posted February 22, 2011 Cheers for the input Dude! I am not going to even pretend I am close to the levels you guys are thinking on when it comes to Supras but Josh mentioned boost guages. The car has a boost guage that was in when I got it which went up to 0.7 / 0.8 bar as expected. A couple of months before this the guage would only go up to 0.5 which is clearly too low but the car felt that it pulled the same and such and it was put down to a dodgy guage. Could any of this point to a boost leak? it seems with the guage playing up it at least seems worth mentioning. I have replaced all the boost hoses circled in white in the pic below and put small zip ties on both ends so its very secure, this was to try and sort the guage issue but its the same and pulls fine, the blue lines show the path of the hoses you cant see if relevant. There are no hard bends and anything that is tied to something else is done very lightly so not constricting the pipe at all. The boost guage feed and input for the boost controller are near the top left of the engine bay also. The only ones I havent changed yet are the hoses circled in red which go to the BOV and off into the darkness, I have heard the pipe fitment on the HKS is a bit delicate so dont really want to touch it. Maybe worth a go if it would make a possible difference? What about damaged preassure tank? Just happy to try few different things really, hopefully Dudes charity dyno day is still on at some point for a second round Cheers all I appreciate it. Quote Link to comment Share on other sites More sharing options...
The-Plethora Posted February 23, 2011 Author Share Posted February 23, 2011 I have decided to replace any remaining boost hoses, can't hurt can it? So I have been careful and changed one length of hose at a time with the correct diameter, still a few bits left to go and I think for some bits I need to get a larger internal diameter hose. Only had a chance to do a few last night before it got too dark. Just a bit lost on the pic below which is taken near the alternator. The area circled has been capped off with a bolt, just to put my mind at rest is this where the stock BOV would be fed from? the pipe seems quite tough and hard to remove. Quote Link to comment Share on other sites More sharing options...
Scott Posted February 23, 2011 Share Posted February 23, 2011 Don't agree with that, in this case all actuators etc are working ok and the BC is set as aggressive as poss its just not holding the boost, most BC's spike then hold the lower boost fine, if this one spiked at 1.4 it may well hold 1.2. If you don't run a restrictor then the boost would stay constant. I don't follow here Dude? Surely the boost controller is connected to the wastegate. If the wastegate is closed all the exhaust gas will be exiting through the turbo spooling it up. With the wastegate held firmly closed the tubbys will make WAY more than 1.2bar. Usually up to around 1.6 before going pop. If the BC is set to 1.2bar then it won't actuate the wastegate until it sees 1.2bar. 1.0bar = closed wastegate. My understanding of the restrictor ring is to put a restriction on the exhaust system so that the exhaust gas is forced through the wastegate, if the wastegate is closed all the exhast gas will be through the turbos. I hit 1.2bar with both cats and a pea shooter exhast in once I had a BC on there. I could have went way higher as during my adjustment I was up at 1.4bar. I was worried about EGTs though so I took it back off and let the ECU stick to it's 1.05 bar (Mines). Obvioulsy I'm not going to tell you how to suck eggs as you are far more knowledgabe and experienced in this field but I can't see how you are coming to your conclusion. Quote Link to comment Share on other sites More sharing options...
dude Posted February 23, 2011 Share Posted February 23, 2011 If for example one of the exhaust boxes had collapsed inside no matter how much you turn the BC up it will not make more boost (had this more than once) therfore if a very small restrictor ring has been put in it can restrict it too much, it could also of course have a weak actuator. Really the RR is there to limit boost AND as important boost creep, this could be doing its job too well. Quote Link to comment Share on other sites More sharing options...
The-Plethora Posted February 23, 2011 Author Share Posted February 23, 2011 I'll keep changing the vac hoses for now I think, probably the most important thing is to get that boost guage back up and running. People have mentioned different things about the inline vac hose filters, one of them bust in half a while back and I simply put a length of new pipe on without a filter (I didnt have one), anyone heard of these getting blocked up with muck or are the filters genuinely needed? I'll try to remove the guage and clean everything running up to it. Any advancement on the bolt capped bit? I am trawling through diagrams and pics . Quote Link to comment Share on other sites More sharing options...
Scott Posted February 23, 2011 Share Posted February 23, 2011 If for example one of the exhaust boxes had collapsed inside no matter how much you turn the BC up it will not make more boost (had this more than once) therfore if a very small restrictor ring has been put in it can restrict it too much, it could also of course have a weak actuator. Really the RR is there to limit boost AND as important boost creep, this could be doing its job too well. I understand that, but surely that is when the wastegate is functioning? If the BC is controlling the wastegate then the exhaust gas has to go somewhere. If the gas that would normally produce 2bar+ is being restricted through a 2" diameter the resistance would cause the EGTs to go through the roof. I have a 2" diameter restrictor ring and I am seeing higher EGTs than I was without it, and that is with an open wastegate to control the boost. If the boost controller is set up correctly it won't open the wastegate till 1.2bar. The fact that the boost controller is only seeing 1.0bar will mean it stays firmly closed. All exhaust gas is therefor directed through the turbos and out through the potentially restricted exhaust. If your theory is correct and there is nothing wrong with the turbos, intercooler piping or the BC setup then the EGTs will most definitely be through the roof.... extremely dangerous (as we all know). Why not just remove the restrictor ring to see if that helps? Would at least confirm the theory. Quote Link to comment Share on other sites More sharing options...
jagman Posted February 23, 2011 Share Posted February 23, 2011 My understanding of the restrictor ring is to put a restriction on the exhaust system so that the exhaust gas is forced through the wastegate, if the wastegate is closed all the exhast gas will be through the turbos. the turbine is connected to the compressor , the turbine uses heat and pressure , one side of the turbine is heat say 1000 degrees , the other after spinning the turbine is say 500 degrees . one side of the turbine is also say 20 psi , the other is say 5 psi (the perfect turbine would have zero temp and zero pressure ) why 5 psi after the turbine - because the exhaust pipe has a back pressure , imagine blowing through a 20 foot straw - the lower the pressure after the turbine the better, the faster and more the turbine spins = faster compressor= more boost You could not have a pipe fitted , but its loud and hot in the engine bay -lol pressure drop and temp drop across the turbine shows how efficient it is, more the merrier the restrictor ring increases the back pressure by restricting the flow down the pipe this reduces the turbines speed and prevents overspinning the compressor/Turbine (too much BOOST ) the ring is fitted because you remove the cat/cats and this reduces the back pressure too much so you put in the restrictor ring - simples - it prevents overboost the wastegate is just a bypass valve , that lets hot gas (heat and pressure) go around the turbine without going through it ,so it slows down Im not sure what you mean ? Quote Link to comment Share on other sites More sharing options...
Scott Posted February 23, 2011 Share Posted February 23, 2011 My understanding of the restrictor ring is to put a restriction on the exhaust system so that the exhaust gas is forced through the wastegate, if the wastegate is closed all the exhast gas will be through the turbos. the turbine is connected to the compressor , the turbine uses heat and pressure , one side of the turbine is heat say 1000 degrees , the other after spinning the turbine is say 500 degrees . one side of the turbine is also say 20 psi , the other is say 5 psi (the perfect turbine would have zero temp and zero pressure ) why 5 psi after the turbine - because the exhaust pipe has a back pressure , imagine blowing through a 20 foot straw - the lower the pressure after the turbine the better, the faster and more the turbine spins = faster compressor= more boost You could not have a pipe fitted , but its loud and hot in the engine bay -lol pressure drop and temp drop across the turbine shows how efficient it is, more the merrier the restrictor ring increases the back pressure by restricting the flow down the pipe this reduces the turbines speed and prevents overspinning the compressor/Turbine (too much BOOST ) the ring is fitted because you remove the cat/cats and this reduces the back pressure too much so you put in the restrictor ring - simples - it prevents overboost the wastegate is just a bypass valve , that lets hot gas (heat and pressure) go around the turbine without going through it ,so it slows down Im not sure what you mean ? Ok, riddle me this then. Why can I put a boost controller onto a stock TT (with both cats and a restrictive exhaust) and increase the boost levels by holding the wastegate shut until 1.2bar? If it is the restrictive cats and the restrictive exhaust that is holding the boost pressure back how can it be controlled by fluctuating the wastegate? We both know the answers to these questions but according to the last part of your explanation the boost can't be increased without a free-flowing system being put in place post turbine. In my opinion there is something wrong elsewhere in the system as the exhaust would have to be from a 1.0l fiesta to only allow 1.0bar in a healthy TT with the wastegate held shut. If it was THAT much of a restriction, the EGTs would be through the roof (hence why it is not recommended to run 1.2bar with the stock cats in) Have you read this whole thread? I've got the feeling you just decided to grab a hold of one point and rant on about it. Quote Link to comment Share on other sites More sharing options...
Scott Posted February 23, 2011 Share Posted February 23, 2011 I have decided to replace any remaining boost hoses, can't hurt can it? So I have been careful and changed one length of hose at a time with the correct diameter, still a few bits left to go and I think for some bits I need to get a larger internal diameter hose. Only had a chance to do a few last night before it got too dark. Just a bit lost on the pic below which is taken near the alternator. The area circled has been capped off with a bolt, just to put my mind at rest is this where the stock BOV would be fed from? the pipe seems quite tough and hard to remove. http://i789.photobucket.com/albums/yy176/The-Plethora/capped.jpg The capped bit used to be a hose going from the VSV to the actuator you have pictured. It isn't required when an EBC is put in place so it is generally just capped off. Not so sure I would be happy with it being a bolt though. Since you have the decats in place I would leave everything as it is and take out the plumbing for the boost controller to see what boost is achieved. My money would be on 1.0bar at this stage in the game To remove the boost controller you only need 2 pieces of hose (if your VSV is still in place). 1 goes from the ratsnest at the top to the VSV and the other goes from the capped end you can see to the other port of the VSV. If you fancy giving this a go I can show you pics and a diagram of how it goes together Quote Link to comment Share on other sites More sharing options...
TTRickeh Posted February 23, 2011 Share Posted February 23, 2011 Just a bit lost on the pic below which is taken near the alternator. The area circled has been capped off with a bolt, just to put my mind at rest is this where the stock BOV would be fed from? the pipe seems quite tough and hard to remove. Pic That hose was blocked off on mine too when I had my boost controller plumbed in, and i've seen fitting instructions that tell you to block it off too. The stock BOV is not fed from there. I'm confused why there's a pipe bridging where the stock BOV is meant to be though, doesn't that get capped off at either end if using a BOV elsewhere? Quote Link to comment Share on other sites More sharing options...
Scott Posted February 23, 2011 Share Posted February 23, 2011 That hose was blocked off on mine too when I had my boost controller plumbed in, and i've seen fitting instructions that tell you to block it off too. The stock BOV is not fed from there. I'm confused why there's a pipe bridging where the stock BOV is meant to be though, doesn't that get capped off at either end if using a BOV elsewhere? Normally you would use a tpiece and just tap in from the manifold AFAIK. No harm in having it where it is though Quote Link to comment Share on other sites More sharing options...
TTRickeh Posted February 23, 2011 Share Posted February 23, 2011 Wouldn't just bridging the two main stock BOV pipes mean you were constantly trying to pressurise an open system though? Like having the stock BOV permanently open and bleeding off boost back into the intake stream? Quote Link to comment Share on other sites More sharing options...
Scott Posted February 23, 2011 Share Posted February 23, 2011 Wouldn't just bridging the two main stock BOV pipes mean you were constantly trying to pressurise an open system though? Like having the stock BOV permanently open and bleeding off boost back into the intake stream? Ahh I'm with you now. Yeah that looks like it might be the problem. Well spotted I thought you were referring to the blue Vac line for the BOV The Plethora, if you remove the pipe from where the stock BOV sits and block off both ends that should be the end of your boost control issues. Your tubbys will have been working extremely hard to make 1.2bar though so might be on their last legs unfortunately Quote Link to comment Share on other sites More sharing options...
dude Posted February 23, 2011 Share Posted February 23, 2011 Wouldn't just bridging the two main stock BOV pipes mean you were constantly trying to pressurise an open system though? Like having the stock BOV permanently open and bleeding off boost back into the intake stream? The pipe is blocked inside by a bung of some sort! We actually managed to sus that one all by ourselves:blink: Quote Link to comment Share on other sites More sharing options...
Scott Posted February 23, 2011 Share Posted February 23, 2011 The pipe is blocked inside by a bung of some sort! We actually managed to sus that one all by ourselves:blink: Ahh, dammit. Thought the saga was at an end there Actually looks pretty good like that, better than it would with 2 stoppers anyway. Quote Link to comment Share on other sites More sharing options...
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