phlanigan

I've reviewed a lot of threads to determine how to switch over to a single turbo setup and I thought it might be helpful to someone to summarize my experience. I've also got a lot of time at work right now...

I wanted to convert to a single turbo with quick spool up rather than monster peak power, and I also wanted to retain all of the stock emissions equipment. Commercially, the t04e and t04r kits from HKS and the Apexi RX6 allow retention of the airpump, unlike the XS Engineering t04e and t04s kits or the various GT 35/40 and T-78 kits.

I also considered piecing together a kit, but decided that I simply didn't have enough time for the necessary hunting and gathering of parts and fabrication services. (If I had gone this route, I would have likely obtained an HKS cast iron manifold and a turbonetics t60-1, per the suggestion of a forum member). I think selecting a 60-1 turbo with a hot side a/r under 1.0 would still allow retention of the airpump, but I couldn't confirm this. Luckily, I found a complete used HKS t04e kit on ebay and actually avoided getting ripped off.

For fuel, I decided to go with a 550 cc primary and 1300 cc secondary setup. Although I would have preferred to go with 1600 cc secondaries, this would require buying an aftermarket fuel rail and fuel pressure regulator. Additionally, I would have to eliminate the air control valve, which would have meant discarding the airpump or potentially messing up the idle by connecting the pump directly to the cat. Given the potential problems, having my 850 cc injectors bored out by RC engineering seemed like the best choice to me. I also could have gone with 850 cc injectors all around, but this would have required machining the primary rail, and seemed like more than I wanted to deal with. I haven't upgraded my fuel pump yet, but I will likely replace it with a Walbro for $85.00 once I get a chance.

For engine control, I have an existing PFC and datalogit. I also have a techedge 1.5 wideband for tuning and an old laptop to control everything. As I wanted to be able to run both a wideband and a narrowband simulaneously, I had an additional o2 sensor bung welded into the downpipe near the flange at the cat.

Some of the kits come with blow-off valves, but the HKS t04e kit is not one of them. After reviewing many threads about the pros and cons of BOVs (most having to do with how cool they sound) I selected the HKS SSQV, as it appears to flow a lot of air quickly and also allows you to buy an optional recirculation fitting that you can attach a hose to. I personally find the noise of a BOV at work pretty annoying, so I'm going to plumb the hose into a ghetto muffler made from PVC tubing and a paint can that I found on a web site. I had the BOV fitting welded onto the pipe running from the turbo to the IC, as it makes more sense to relieve the pressure from as close to the turbo as possible.

Lastly, for boost control I found an HKS EVC IV used. Now, I debated simply buying the Apexi AVC-R solenoid to control the external wastegate the comes with the HKS kit and using the PFC to control the solenoid. I also could have bought the Apexi Boost Control kit and gotten both the solenoid and the 3 bar map sensor. In the end, the HKS EVC kit was only slightly more than the solenoid, and may offer the advantage of better boost control and faster spool-up than that provided by the PFC.

The biggest problem I ran into was when I damaged one of the nuts holding the stock turbos onto the manifold. Specifically, I completely rounded the recessed one on the bottom of the turbos, which made it impossible to get vise grips on it. I ended up getting "Bolt-offs" from Sears that worked like a charm. Unfortunately, you can't just buy one of them, so I'll be returning the $59 set of 10 this weekend. I'm also leaving the rats nest in place, but I could remove basically all of this except for the fuel pressure regulator solenoid.

Costs:

1200 HKS t04e turbo kit
350 1300 cc injectors
175 HKS EVC IV
200 HKS SSQV BOV & flange
170 welding, misc fasteners, tubing, and fittings
_____
2095

The datalogit/PFC/WB combo and an upgraded intercooler adds another 2K to the total, so I came in at just over 4K for a single conversion. Not too bad...

phlanigan

Part II

A couple of minor things caused a bit of a delay.

First, to install the SSQV BOV, you need to have a pair of retaining ring pliers ($20) to install the device onto the welding flange. Had to go out and get a set of these.

Second, the oil feed line to the turbo was leaking from one of the fittings. The HKS t04e uses a 1ft section of AN-4 braided line, so I bought replacement line with new fittings ($35). I was hoping to just cut off the leaky fitting, but I want to get out on the road and just buying a new line was worth avoiding any further delay.

I'll be able to get these pieces on tonight and start tuning. I still have to install the EVC, but I want to ensure that everything else I've installed functions before adding another piece. I'll use the right-foot boost controller until then, and the HKS kit comes with the wastegate set for 10psi.

Highrevnrx7

So what all did you have done to your car before you went single. Im going to try to do something like that.

Chris

phlanigan

I have an SR Motorsports SMIC and a PFC/Datalogit/Techedge wideband. I'm still running the stock clutch, at least until I smoke it. On a 90 degree day, intake temps are 50-60C after the IC has heatsoaked.

Other than that, I've replaced/upgraded shocks and some suspension bushings. I'm also still running a stock radiator until I notice any problems with heat.

Highrevnrx7

Where did you find that turbo kit at for that price. That is an awesome deal. Im going to start looking for stuff. Its too expensive to go single with new stuff. What kind of exhaust do you have.

phlanigan

I rolled the dice and bought it off ebay. The seller claimed there are only 100 miles on the turbo, and the parts seem to reflect the claim. Turbo spools well and no smoke of any type. I had to spend around $75 to get new oil feed and drain lines and gaskets for the kit, but t04 stuff is easy to get from turbonetics.

There is an HKS t04r kit on ebay right now that was only at $300 when I checked earlier today.

I forgot, I have a Racing Beat single tip exhaust. The exhaust note is slightly deeper at idle than stock, and louder off idle. Sounds great at WOT. No drone whatsoever at highway speeds. The single definitely makes more noise than the twins with this exhaust, but it is a raspier, mean sound. I'm still running the stock cat.