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Hey guys,

I've mentioned here and there about turbocharging Dragon; I'm now finding motivation and cause to give it a try myself. I'm not gonna ask the old questions; don't worry, I'm doing my own research. I'm fortunate to have an uncle who's turbocharged Capris before, so he's my first port of call for advice. I'm making this thread to throw around and collect ideas, and hopefully get some feedback that I'm heading in the right direction.

So, why molest my pride and joy? Well, two reasons. First, and it's a minor point, 178 horses really isn't a lot - the 86 gets 200 horses out of a 4-cylinder, and that's not even turbocharged! So I want to see if I can push the HP above 200 to justify having the extra 2 cylinders. Second, more importantly, a close friend has a mk4 Supra, and it is an animal - 400RWHP with no modifications apart from a boost controller (at 1 bar), and when that second turbo kicks in, it's insane. I found out exactly why people say boost is addictive - I'm already hooked!!

Dragon's engine is in good health so far; it has a few subtle modifications and was dyno'd in 2006 at 150RWHP. The technician commented that the engine was remarkably strong after 20 years. Since then, it's covered less than 10,000 miles, so I'm hoping few of those horses have escaped!

I like the idea that turbocharging is a well-understood and practical approach, that these engines can take it and getting the parts off the mk3 is easier than having anything custom-made. My uncle is going to lend me some books on forced-induction so I can better understand what's involved, but here's my high-level approach so far:

  • Exhaust manifold, turbo and injectors off a mk3 (of course)
  • Complete bypass of the original engine electronics using an Electromotive TEC II for both fuel and ignition
  • Fitting knock and exhaust oxygen sensors to keep an eye on combustion
  • Dispense with the AFM and fit a MAP sensor to the intake
  • Being an '86, Dragon has higher compression (9.2:1?) so I would fit a thicker head gasket to bring the compression down
  • Instead of an intercooler, fitting a charge air cooler for a few reasons - no need to hack apart the engine bay to run piping, straighter air path from the intake to the cylinders, keep the battery and easier to revert to stock
  • Fitting an oil filter relocation kit and using the output from the filter to feed oil to the turbo, then back to the block
  • Dragon already has a mk3 fuel pump fitted as the mk2 pumps (at least in the UK, I haven't seen much about the US ones?) are known to have dead spots where the pump will not start again
  • Dash gauges for oil pressure, water temperature and boost
  • I may have the opportunity to lay my hands on a whole 5M-GE; in which case I would assemble the whole thing in a workshop and test before fitting to the car, and keep the original engine unmolested

I'm not looking to run high boost; I'm happy to start off with a few PSI and go from there. I basically want to combine the best of the mk2 and mk3 (call it a mk2.5 :D) - the light body of the mk2 with the boosted power of the mk3.

Oh, and while I'm pouring on the power, I haven't forgotten about stopping afterwards; Dragon's brakes have been overhauled recently and are very sharp now, but they are fully stock. I haven't needed to throw out the anchor yet, so I think the stock brakes are pretty good. I still have the original 14-inch wheels so I would rather keep them stock - is this likely to be my undoing? I'll definitely put performance brake pads on my shopping list if that will be enough.

What I'm going for here is a sleeper - I love subtle modifications that either aren't there unless you look for them, or are completely hidden. If it looks factory-fitted, even better. The tailgate is a blank slate at the moment, and the most I want the exterior to change is '2.8i turbo' on the back. If anyone pulls up at lights thinking 'wow, look at that clapped-out 30-year-old car! I'll have him off the line!' and actually goes through with it, I would be more than happy to show them what Dragon's made of!

And the big reason I'm doing this now? I turn 25 in May, which is the cutoff for cheaper insurance. I have 6 years' accident-free driving under my belt, but believe me, I'm not trying to change that. If anything, I think I've levelled up sufficiently to have a more powerful car :thumbsup:
 

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Hi Rob,

I am a little off topic here, but I am curious to hear about how emissions and/or safety inspections could affect your plans.
Up until this year in Vancouver Canada there was an annual vehicle emissions test that one had to pass before being able to purchase vehicle insurance. In California there is an exceedingly strict inspection which does not just look at emissions levels, but requires a visual inspection of the vehicle to ensure it met original emissions laws.
I do not know much about your MoT and how you license your vehicle in the UK, but will this present any issues with your plan to turbocharge?

Dale
 

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Discussion Starter #3
Hi Rob,

I am a little off topic here, but I am curious to hear about how emissions and/or safety inspections could affect your plans.
Up until this year in Vancouver Canada there was an annual vehicle emissions test that one had to pass before being able to purchase vehicle insurance. In California there is an exceedingly strict inspection which does not just look at emissions levels, but requires a visual inspection of the vehicle to ensure it met original emissions laws.
I do not know much about your MoT and how you license your vehicle in the UK, but will this present any issues with your plan to turbocharge?

Dale
A very valid question Dale. Fortunately the UK MOT does not require classic cars to meet current MOT criteria; they are instead assessed based on the criteria of their time. Emissions checks came back extremely clean anyway (somewhere around 1% of the allowed maximum for HCO and NOx). A sports catalyst is on my to-buy list in future too, but not a high priority because of the clean exhaust.
 

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Charge air coolers range in size depending on the engine. The smallest are most often referred to as intercoolers and are attached to automobile engines or truck engines.

What do you mean? they are the same thing. Intercooler=Charge air cooler
If you are gonna use a map sensor you are gonna need a different ecu and the right sensor, maybe one from a supercharged pontiac grand prix.
Ah, when talking to my uncle, we understood a 'charge air cooler' to mean an air-water-air cooler, like so:
http://www.chargecooler.co.uk/index.php?main_page=product_info&cPath=72&products_id=212

I'll research the MAP sensor. The ECU I have lined up supports it, so as per my first post, I'll be bypassing all the original engine electronics and wiring everything into the TEC.
 

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that makes more sense, as good as they are though...the smaller, the less they cool the charge. In my previous turbo experience, if you are never gonna go to or above 10psi you really don't need an intercooler.
 

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Everything you actually do need...CLICK ME!
No sense in having a bunch of extra hoses, and pumps and what not. Its just extra stuff that can go wrong, extra things to leak, and extra things to get you kicked off the track. It would diminish turbo lag. But I would just get a normal front mount intercooler and paint it black, so no one will take notice. These cars have enough hoses and shit on them already. I'm not familiar with the ecu you speak of.
 

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Sounds like you've got a great go to guy to ask things. I too have considered an air to water cooler, but am still flip flopping between that and front mount air to air of course. The only reason people move their oil filters is to make it easier to change them when running mk3 style IC piping which runs right next to it, so if you go air to water don't bother with that mod, one less thing to buy. The cheaper cast oil filter relocation kits tend to break. Instead of tee-ing off the oil filter relocation you're better off teeing off at the oil pressure sensor in that area. Here is an old kit i picked up unused that i'm adding to my turbo conversion stockpile:

The oil pressure sensor threading in the block is actually BPT so you could prolly easily find a T that works locally you lucky brit :p The other big hose is the drain, and it has a bung that i need welded onto a pan. The flange is for a ct26, i'm still trying to find a mk3 turbo and manifold... Our intake goes over the valve covers and back towards the exhaust like the 7mgte's, which is why the mk3 style intercooler piping works ok for us too. If ours were a front facing intake moving the battery(to the hatch, or smaller one in the windshield spray bottle warea even) would help free up space for running piping there, but it isn't so... Here is the old RC turbo kit thread to give you an idea of a mk3 turbo manifold on our engines and how the mk3 style ic piping is run.
http://www.celicasupra.com/forums/showthread.php?38758-5m-6m-Turbo-Kit
Good pics of the IC piping and how it runs right by the oil filter if you don't move it. Some people are fine with removing that pipe to do oil changes, some people would rather relocate it to make it easier...



More of that kits pics for inspiration. Beware though, if you post these pics or ask for 5m/6m turbo kit pics Tanya will show up in short order it seems. Kind of like saying beetlejuice or candy man :p



As for cooling, you can interrupt the lines that go to the throttle body, as there has been no cases of tb ever icing up like those are meant to protect against. Here is an old rabid chimp kid i've got for that... Just big long 5/16 hoses and flanges for ct26, nothing fancy


As for brakes, run some better pads and call it good. You could upgrade to stainless lines if you want a firmer pedal, but it is not 100% needed if yours are fine. If you want to run your stock wheels the best you can hope for is a cressida brake upgrade, though getting those parts where you are might be tricky.


Lucky for you there is someone on this here very forum selling a tec2 for a good price off a 7m, about all you would need is a wheel to bolt on your crank pulley to rework the hall sensor mount. Even comes with a manual with a bunch of notes written in there it looks like. If i didn't already have my standalone purchased i would have snatched it up.
http://www.celicasupra.com/forums/showthread.php?82961-Random-parts
 

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Everything you actually do need...CLICK ME!
No sense in having a bunch of extra hoses, and pumps and what not. Its just extra stuff that can go wrong, extra things to leak, and extra things to get you kicked off the track. It would diminish turbo lag. But I would just get a normal front mount intercooler and paint it black, so no one will take notice. These cars have enough hoses and shit on them already. I'm not familiar with the ecu you speak of.
Thanks for the link. Note the main reason I don't want to mount an air-air intercooler is that I don't want to cut holes in the engine bay for the pipes. I've seen how the intercooler is commonly fitted and it makes a real mess of the engine bay; I want mine to look like it was factory-fitted. The charge cooler requires a hack of a lot less space, has smaller water lines that can be routed independently of the air path (keeping it straight from the turbo to the manifold) and because water has a higher thermal capacity than air, a smaller charge cooler can have the same capacity as a large air-air intercooler.

I'm open to suggestions though, if you don't think the cooler is necessary, but I'm aware pressurised air comes out of the turbo along with quite a lot of extra heat.
 

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As for brakes, run some better pads and call it good. You could upgrade to stainless lines if you want a firmer pedal, but it is not 100% needed if yours are fine. If you want to run your stock wheels the best you can hope for is a cressida brake upgrade.


There is someone on this here very forum selling a tec2 for a good price off a 7m, about all you would need is a wheel to bolt on your crank pulley to rework the hall sensor mount.
http://www.celicasupra.com/forums/showthread.php?82961-Random-parts
Already got stainless lines (and they do make a difference!), and the TEC II you've linked is the very one I am currently pursuing. Hoping the seller will get back to me with a price for shipping.
 

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Already got stainless lines (and they do make a difference!), and the TEC II you've linked is the very one I am currently pursuing. Hoping the seller will get back to me with a price for shipping.
I edited my post to clear some things up for you. About the only other thing i think you are missing in your list is bigger injectors and a fpr, getting a nice 1:1 boost referenced regular for ~100 bucks that is adjustable would be a huge help over the stock one.

I wish you nothing but the best of luck on this, even if your sig pic is impossible to read for red/green color blind folks like me hehehe
 

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I wish you nothing but the best of luck on this, even if your sig pic is impossible to read for red/green color blind folks like me hehehe
There's something to read on his pic? Where?
 

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do yourself a favor and get an Ebay T4 manifold and then shell out a little extra for a T3 or T4 turbo. i know the MK-III stuff looks appealing but by the time you get a good CT-26 or finnish paying someone to rebuild it you will have spent enough to take the T4 route.

the CT-26's are getting pretty old now and they leave little room for expansion. if your EVER going to want more than like 350HP id seriously recommend just doing an aftermarket single setup right out of the box.
 

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Hey guys,


[*] Being an '86, Dragon has higher compression (9.2:1?) so I would fit a thicker head gasket to bring the compression down

I'm not looking to run high boost; I'm happy to start off with a few PSI and go from there. I basically want to combine the best of the mk2 and mk3 (call it a mk2.5 :D) - the light body of the mk2 with the boosted power of the mk3.
No need to use a thicker headgasket since you're not building a pure 1/4 mile drag car and trying to rely so much on the turbo. The reason factory turbo cars used to be such low compression back in the day was that the engineers didn't feel the technology was up to their warranty requirements. Back in the day as we started bolting these turbos on, unconcerned with emissions, we just made sure we dumped enough fuel under boost and retarded the timing a tad to keep it from detonating. Since you'll be going with a modern programmable fuel and ignition management, all you need to do is tune it on a dyno with a wideband and gas analyzer and you'll be more reliable and cleaner than we could have ever imagined. The higher static compression will give you quicker turbo spool up and better torque at lower rpms, i.e. better acceleration. A NEW headgasket would probably be a good idea along with some ARP bolts but thicker is not necessary.
 

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No offense, but personally to me reading your post its sounds like your trying to build this in 1995 vs 2015. There are so many better parts these days to use. The TEC2 is ancient tech these days. Spend a little more and get a newer VE tuning based ECU. They tune so much easier than the old method and are more flexible for upgrades and have protections built in.

Turbo wise I'd second the recommendation to get a regular T4 manifold. Although I'd look for a cast version to keep heat down and minimize spool time. Any used CT26 you buy is going to need to be rebuilt and those are hit or miss. When you rebuild it you'll be tempted to upgrade which has an even spottier reliability. Unless you are trying to fly under the radar you'll do so much better with a quality aftermarket turbo. Newer turbo are way more efficient.

Intercooler get one. Intake air temp is the enemy with turbo cars. There's no reason you have to cut the car to have a smaller intercooler with the 7MGTE pipe routing. If you have a larger intercooler you will have to trim the bottom of the hood latch bracket. These bolt on so a second one can be sourced pretty easily if need be.
 

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No need to use a thicker headgasket since you're not building a pure 1/4 mile drag car and trying to rely so much on the turbo. The reason factory turbo cars used to be such low compression back in the day was that the engineers didn't feel the technology was up to their warranty requirements. Back in the day as we started bolting these turbos on, unconcerned with emissions, we just made sure we dumped enough fuel under boost and retarded the timing a tad to keep it from detonating. Since you'll be going with a modern programmable fuel and ignition management, all you need to do is tune it on a dyno with a wideband and gas analyzer and you'll be more reliable and cleaner than we could have ever imagined. The higher static compression will give you quicker turbo spool up and better torque at lower rpms, i.e. better acceleration. A NEW headgasket would probably be a good idea along with some ARP bolts but thicker is not necessary.
Wow, that sounds good! Thanks for explaining it to me, that really helps. I have a Toyota head gasket set in the garage, and if I have a second engine, replacing the gasket (and overhauling the engine) could be much easier.

No offense, but personally to me reading your post its sounds like your trying to build this in 1995 vs 2015. There are so many better parts these days to use. The TEC2 is ancient tech these days. Spend a little more and get a newer VE tuning based ECU. They tune so much easier than the old method and are more flexible for upgrades and have protections built in.

Turbo wise I'd second the recommendation to get a regular T4 manifold. Although I'd look for a cast version to keep heat down and minimize spool time. Any used CT26 you buy is going to need to be rebuilt and those are hit or miss. When you rebuild it you'll be tempted to upgrade which has an even spottier reliability. Unless you are trying to fly under the radar you'll do so much better with a quality aftermarket turbo. Newer turbo are way more efficient.

Intercooler get one. Intake air temp is the enemy with turbo cars. There's no reason you have to cut the car to have a smaller intercooler with the 7MGTE pipe routing. If you have a larger intercooler you will have to trim the bottom of the hood latch bracket. These bolt on so a second one can be sourced pretty easily if need be.
None taken. Haha, don't worry, I'm actually quite into older technology because I struggle to keep up with the current paradigm; I'm aware the TEC II is technically obsolete but I think it would better suit the older engine, plus it's cheap - over here, I'd be looking at £1,000+ for the ECU and wiring loom, and that ECU would be overkill. My uncle is fitting an LS-1 to a mk1 Capri and will be going with an Emerald ECU (British made). I looked these up and they are supremely complex, with features I'd never use. I think the TEC II, whilst old, fulfills all my requirements. I am certainly open to upgrading the ECU if it reach its limits, but as I'm not on a brilliantly high income, the high cost of new(er) electronics is not one I can justify if I can find something that'll do the job for cheap.

That said, you guys suggesting I go with a T4 turbo, I'll look into it. I've noticed the problem of end float on older turbos when watching Wheeler Dealers, so I'm aware the turbo coming off the car would probably need attention. I assume I could get a bearing kit for the CT26, but I guess if it's a device that'll be spinning upwards of 100,000RPM, it would be better to trust a professional to overhaul it which would cost. If I can get a new T4 for less or the same as a CT26+rebuild, I guess that's better value for money.

And as stated before, I don't want to go with the hassle of an air-air intercooler, I'm planning to use a charge cooler instead. This means a straighter air path from the turbo to the intake, an overall smaller unit that can sit on top of the valve covers and a small water radiator. I want to be able to revert the car to stock form if necessary, which is why I'm going for these kinds of modifications.
 

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I edited my post to clear some things up for you. About the only other thing i think you are missing in your list is bigger injectors and a fpr, getting a nice 1:1 boost referenced regular for ~100 bucks that is adjustable would be a huge help over the stock one.

I wish you nothing but the best of luck on this, even if your sig pic is impossible to read for red/green color blind folks like me hehehe
:thumbsup:

I was planning to take the injectors off the 7M-GTE, since I understand these will plug straight into the rail, and they ought to be sized appropriately. Do I really need an FPR with a fully customisable ECU?
 

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Well, if you do both you will have more control, plus a gauge built into the fpr to show you what your pressure actually is would be a help.
 

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If you aren't adding much boost a boost reference fpr isn't a huge deal, but think about the effect the boosted air pressure has pushing against the injectors. Say your fuel injectors push out with the force of your 40psi fuel pressure, if you are running 10psi of boost all of a sudden your injectors are only pushing out with 30psi of force. A 1:1 ratio boost referenced fpr basically adds one pound of fuel pressure for every pound of boost it sees, so you are always pushing out the same amount of force essentially.
 

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A programmable ECU will allow you to run larger capacity injectors like those off the 7mgte. That way you can flow more fuel at the same stock fuel pressure, but it will still idle correctly because it can reduce the time the injector stays open. The rising rate fuel pressure regulator was invented as a way to circumvent the stock ECU and add more fuel during the 2% of driving that the turbo is spooling up and still run like normal the 98% of driving that the turbo is not in play. The rrfpr is hard on fuel system components, making them tolerate pressure spikes and shortening the life of injectors, pumps and hoses.
 
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