Carl's ST Rocket Build

[airforceone]

which size did you get the normal or excel ones.

[carlostheoptimistic]

Normal.

[carlostheoptimistic]

Well it looks about time for an update seen as its been nearly a year since the last post!

So at the end of last year I got hold of a couple of front wing elements from an old small formula car and made myself a small front wing thing.

I also built and installed some shift lights of an F1 type style. They are in the edge of the bonnet facing the driver and can be seen just above the steering wheel. They are a curved line of LED's, the first 8 are blue which start to light up one by one as you get to the top end of the rev range and then there are 4 red ones that come on together when its time to change up a gear. I've just realised I haven't got any photos of them! I'll do a little video of them once the car is running again.

So that was the end of summer last year.

Since then I've done some maintenance and mods;

1)  Change the drive shaft oil seals in the diff. These were weeping a bit of oil, one more than the other

2)  Modify the exhaust system. I've put the cat back in to try to quieten it down a bit

3)  Fabricate and fit a brace bar to the front suspension points as per the important build guidance notes

4)  Fit a set of bike throttle bodies

5)  Change the ECU to run the new throttle bodies

So the oil seals, exhaust and brace bar were pretty straight forward. I made the brace bar out of alloy tube, 28.6mm (1 1/8") diameter by 3.3mm thick wall (10swg), I squashed the ends flat in a vice (using lots of heat so not to crack the edges) and then rounded the ends off, drilled holes and fitted it to the wishbone mounts using longer bolts.

The throttle bodies have been a whole different adventure! I had a plan, but as these things do, it changed.

I was on a tight budget to get the throttle body conversion done so was delighted to find a set of already re-spaced 40mm bike throttle bodies on ebay at a good price (£72) and what made them really good was that they had a zetec manifold with them too! When they arrived I was less impressed, the throttle bodies were 38mm not 40mm, they had been re-spaced with some random bolts, no spacers in between so the only thing holding them apart was the silicon hoses attaching them to the manifold, the whole assembly flexed! And the manifold was glued together! yes that's right, the tubes coming off the flange plate were glued in, not welded. So they went back in a hurry! Note to self (again!) if something looks too good to be true then it probably is!

I went back on the prowl for some throttle bodies and ended up with some Hayabusa bodies with injectors and TPS for £135.

I re-spaced them using some alloy tube for spacer and longer threaded rod. The fuel rail on the hayabusa throttle bodies are made up of plastic pieces where the injectors attach and alloy joining pieces in between. I planned on making new longer alloy joining pieces on the lathe and them joining into 2 of them for the fuel line connections. the pic below shows the re-spaced bodies and the new joining pieces.

I managed to manipulate (bend) the mechanism that connects the butterfly valves together and get them all working together.

Next was an ECU, as I'm an electronics bod I decided to go for a Megasquirt DIY system, I've heard good things about them and the thought of putting it together didn't faze me. So one was acquired and put on the shelf while we got Xmas and new year out of the way.

Over Xmas something good happened, my mother in law decided to buy a new car. Why is this good you may ask? Well, the car she had already was an 05 plate Mini Cooper Works with only 15,000 miles on it. She had had it from new and it had been looked after. She was changing it for a new Fiat 500 and the dealership had offered her next to nothing for the Mini (as they do). So she asked me if I want to buy it for the same price as the dealership had offered. I took it for a spin and found it was much more fun than the diesel Mazda 3 I was driving at the time, so we did the deal. Now the other side to this is that the Mazda I had was also low mileage and newer than the Mini and I was able to sell it for more than I paid for the Mini, so the extra cash went into my kit car fund! (well some went into the hole that was left from the wife's Xmas presents!).

For the ECU I had planned on using the Megasquirt to run the show but keep the standard ECU (piggy backed) to run the VVT, I had looked into it and thought (by the way of some electronics trickery) I could make it work. However with new funds available I started looking at other options. This led me to the Motorsports Electronics ME221 ECU, the same one Casesesitive is using in his build. It costs more but runs the VVT properly as well, they also come with wiring looms.

The new funds also allowed for some more new bit to be bought;

Alloy manifold to suit re-spaced throttle bodies, velocity stacks (trumpets) and air filter all from DanST engineering.

So it's starting to come together. Since the above pic I have fitted and wired in the ECU, modified the fuel tank to have a return line, fabricated and fitted a bracket for the throttle bodies and knackered the new longer joining pieces for the fuel rail (another story ). I've ordered a new Omex fuel rail now, just waiting for it to be delivered. Once the fuel rail arrives I will be attempting to start up the engine, videos to follow.....

[kiwicanfly]

I'd love to see a pic of the first tb's you bought.

[Stiggy]

can we see a picture of the shift lights please?

[carlostheoptimistic]

Kiwi, I've found a couple of pics of the first throttle bodies for you, they're not great.

The photo on the ad was this

the guy then said that he was waiting for the air filters to arrive before he sent them? so I said to send them without because I was going to fit velocity stacks anyway. The ones that arrived are shown below.

They're not the same as the ad, you can't fit individual air filters or velocity stacks to these.

I'll sort out a video of the shift lights when I get the car running again.

[carlostheoptimistic]

Here's a quick pic of the end of the brace bar on the suspension mounting point, doesn't really show much.

I've got a few days off this week so I've been able to get the engine running today! and it started pretty much first time. I need to tidy everything up a bit and put the rest of the car back together, the seats are still out and covers off stuff. But weather dependant I might be back on the road this week. Here is a very short video of one of the first start up's, the sounds not very good.

[carlostheoptimistic]

Quick update, after getting the engine running again I've not had loads of time on the car. I've managed to get the air filter on and tidied up the engine wiring and plumbing a bit, but it still needs a bit more of a dressing up to look better.

I've got some maps for the ECU from another ST170 with GSXR750 throttle bodies on it, it seems to run ok but needs a proper tune. Also at first, but after the initial start up, I had trouble getting it to start and it seemed to be flooding. I have had a play with the starting fuel trim and it starts better now.

I've put the drivers seat back in and drove it round the a bit, it got really hot cause there was air trapped in the system, I've got that out, I hope!

I need to put the passenger seat back in but first I need to put the fuel tank cover back on, I've left it off cause the ECU is mounted on the rear bulkhead behind the drivers seat and I wanted access to it until I had any wiring etc. done. The wiring is all but done apart a speed sensor from an un-driven wheel, so I needed to put one on one of the front wheels. This will feed a speed signal to the ECU to disable launch control over a set speed. I've got the launch control working just on a switch on the clutch pedal at the moment but every time you press the clutch you enable it and limit the revs to 3000rpm (or what ever it is set to in the set up) which is not ideal for blipping the throttle on fast down shifts etc.

I'm hoping to get some time on it at the weekend so will post some pics and vids if I get it sorted out.

[carlostheoptimistic]

So I got the speed sensor mounted (temporarily, need to make a proper bracket) and wired it in. The spare digital pin into the ECU is now getting toggled high and low by the speed sensor but I can't get the ECU software to do anything with it, so I've e-mailed the guys over at Motorsport Electronics for help. They have been really helpful in getting other stuff going so I should have that sorted soon.

The fuel tank cover is back on and the Passenger seat is back in so I'm back on the road!

I took a couple of photos but photo bucket seems to be on the blink so I'll upload them later. For now as promised, here is a quick video of the shift lights I made and fitted into the bonnet.

 

[carlostheoptimistic]

The guys at Motorsport Electronics came good and sorted out a bug so I now have a speed reading into the ECU, just need a dry day to try the launch control out.

Photo bucket is working again, just, so here's a couple of pics of the new intake set up.

[olberj]

Nice one. You'd recommend the ME221 then? Are you tuning it yourself?

I've been looking at the plug n play loom package to run my SC'd ST170.

[carlostheoptimistic]

Yeah I would, the interface/tuning software for it is good and the guys at Motorsport Electronics have been great help. One thing I'm not sure about is the data logging, it doesn't appear to have internal memory so you have to have a laptop attached to log to. Not sure if this is the case as I've not had a good play with it yet but if so then it might be tricky in a Rocket. I got the plug and play loom and it fitted fine with the ECU mounted on the rear bulkhead behind the drivers seat. I've got Hayabusa throttle bodies on and got hold of some maps from a tuned Rocket with GSXR750 throttle bodies so it runs pretty well, but does need doing properly. Not sure if to do it myself or not, I've not got a wideband 02 sensor yet so need sort that out.

[olberj]

Does it have a separate connector for the laptop or does it use the obd2 port?

I was thinking of either extending the obd2 to under the dash or a decent bluetooth reader.

[carlostheoptimistic]

Yeah it has a separate serial port, connects to your laptop with a serial to USB lead. I've just got a lead coming out under the fuel tank cover at the moment, I'm going to fit an IP rated USB socket on the centre tunnel behind the divers seat.

[carlostheoptimistic]

So the last few weeks have been taken up trying to get the car to start better and run better, I have ordered a wideband O2 sensor kit but it has not arrived yet so I've been adjusting things very cautiously. The starting issue was a pain, it seemed to be not firing all the time and flooding. I backed off the cranking fuel trim but it still wasn't starting that well, so I started having a look at some of the map files on the Motorsport Electronics google drive where they share stuff. Looking at the other maps the setting for the VVT rest position were different so I tried building new map files offline and then uploading them onto the ECU and tried some different VVT rest positions, I backed up the files off the ECU first. This didn't go well because the car would not start at all I even went back to the back up of ECU files and it still didn't start! Lots of checking turned up that a bunch of settings for outputs had changed, I can only think that I must have built a file with the wrong setting in. So I carefully built a new file and double checked all setting and it starts much better now

Next was on to the general running, it ran ok but at wot in the midrange the engine struggled to rev and spluttered and popped a bit. As I didn't have a wideband O2 I checked the spark plugs and they were black and sooty so it was running rich. This gave me the confidence to back off some of the corresponding values in the base VE table which improved things. I also backed off the values in the acceleration enrichment table which dumps in extra fuel if it sees a fast change on the TPS. This also made things better so I think that it is running a bit rich in general. I'm going to leave things now until the wideband is fitted.

One thing I can say is that the engine sounds awesome with the throttle bodies on, I need to find a way of videoing it with good sound quality.