MX150R Supercharging Project

[mscott]

MX150R Supercharging Project. Part 16.


Intercooler Time..


Now I had the “Heavy Bits” done I had to mount the InterCooler (IC).




Taking inspiration from one of the Red Rascals cars and needing some way of fitting my Front Tow Strap (needed for racing plus I use this load and unload the car on my car transporter) I decided to build a Crash Box around the front of the SC. At the same time welded in a “Captive Nut” to be able to bolt the Tow Strap in from the Front without needing to be abler to get a spanner behind it.


I started by making the top plate and making some “Speed Holes” in the top. This then bolted to the top mounting posts on the IC and was welded to the Front Cross Member on the chassis. I then built the frame around this and welded this to the chassis.






The bottom IC mounts were made to be removable as there would have been no way to get the IC “In or Out” if I hadn’t. These were 2 simple right angled brackets that bolted to the IC lower mounting posts and then were bolted into “Riv-Nuts” fitted in the lower chassis Cross Member. This could only be done with the Coolant Radiator removed, but not a major issue.


Now the IC was mounted I had to fabricate some Pipework from 63mm Aluminium Pipe from various bended sections. Not the most fun job (or prettiest results) and I need more Aluminium welding practice on very thin wall pipe, but eventually I got there.






The old Cross Over pipe was trimmed down as I still needed some way to mount the AIT Sensor and connect to the IACV, and the SC Outlet was also trimmed to connect to the IC pipework but these were much easier to do as they were both made from Stainless. Silicone Hoses & Bends were used to join the lot together, the only issue being I had to notch around the Lower Engine Cooling Radiator pipe but it shouldn’t cause any issues.



Last bit now is the Nosecone, lots and lots of little trimming operations were made until it could now fit around the IC pipes. Easier to keep taking it off than stocking it back on, and it doesn’t look too bad from where I’m standing.



Whilst the Welders were still out I made a bracket to hold the Expansion Tank bottle from a Suzuki Swift to the Chassis Rail. I welded a couple of extra nuts on the back of the bracket and these hold the Over-Flow pipe.

[mscott]

MX150R Supercharging Project. Part 17.


Fuel Tank alterations..


..DO NOT TRY THIS AT HOME.. I believe is what they say on TV..?


Now not being completely mad and not trying to kill or maim myself I left the fuel tank to dry out completely to the point where it didn’t even smell of fuel, that said I still am aware that even a small amount of fuel vapour in a confined space equals BOOM..


I tested the waters so to speak at “Arms Length” with a lit blowtorch and nothing so safe to play with then.

The Fuel Filler is on the side of the tank, no use to me so I carefully cut it off with a grinder along with the breather pipe, I then cut down the Filler Cap flange to size for top mounting of it.








The Top Vent in the centre of the tank was removed and I then “Hole Sawed” a hole to match the Filler Cap Flange. I think this must have been made from Stainless as it was a bitch to cut, (if I ever do another I cut around it, make an adapter plate and Weld that to the Tank first then that to the Filler Cap Flange) but eventually it went through.



Now typically this was a Sunday when I decided to do this and I was just about to run out of Argon for the TIG so I had to use the MIG to weld it.


This wasn’t the best idea as getting an Air/Fuel tight weld in thin metal with a MIG is more difficult that the TIG. With the TIG you can see the Weld Pool forming and it’s easier to control. The MIG just adds more filler to the area making it harder to see the real join area.




I cut out a couple of Blank Plates to fit the holes where the original filler and breather had been, cleaned up the area and Tack Welded them into place. I then Tack Welded the Filler Cap Flange to the top of the tank and then pulse welded it all shut.



The next mod was to fit a Breather Pipe Inlet/Outlet into the Fuel Pump/Level assembly as I had now removed the Tank Vent. As I had a spare assembly I’d previously bought for a spare fuel pump I cut of one of the Fuel Supply/Return Inlets/Outlets. This was then welded into a hole I had drilled into the Fuel Pump/Level assembly so now I have 3 Inlets/Outlets on my tank and I would be able to vent through the new one to a 1 Way Breather Valve. At least I had enough Argon to TIG this in place.



Before putting Fuel back in I decided to Pressure Test with Compressed Air and a Soapy Water Solution, and of yes it had a couple of Pin-Hole Leaks in both the blanking plates and the Filler Flange. I over-welded the leaks 1 by 1 and tested again, fix 1 and a smaller 1 would show. I did this 2 or 3 times each time testing between.


On 1 of the Welding sessions I noticed a strange smell. I stopped welding and noticed I’d forgotten to remove the Fuel Cap after the last Pressure Test and it was on fire and melting into the tank. I threw some water over it and removed it before it became permanently attached to the tank, bollocks now what was I to do on a Sunday?


I still had the contact number for the guy who I’d bought the Prop Shaft end off previously. He’d said at the time that if I needed anything else then to call him so I did. He agreed to meet me to collect the cap and I asked him how much, he said a Box of Yorkshire Tea Bags (no seriously he did) so I popped into ASDA and grabbed a box. It’s got to be the weirdest currency I’ve ever bought anything with but I needed a Fuel Cap and it works for me…




I finally finished welding any pin-holes and the tank was sealed. I had some Stone Chip still in a can so I sprayed the Blank Plates to match the existing stone chip on the tank. The only thing left to do was to fit the 1 Way Breather Valve which was as simple as fitting a length of Rubber Fuel Pipe to one side and the other to the New Outlet I’d welded on the Fuel Pump/Level Assembly and securing the Valve to a spare flange on the fuel tank. Job done!

[mscott]

MX150R Supercharging Project. Part 18.


Rear Cover & Lights..


The Rear Panel now needed to at least be modified to allow for the Fuel Filler Cap change (once I'm happy with the Tank Mods), and besides the rear lights needed to be wired to the car somehow.


The original Rear Lights were removed, they looked awful and as this was a Race Car Indicators, Reversing and Fog Lights were pointless. The Original Rain light was a Standard 21W Fog light this also had to go.




Once all the old lights were removed I filled the old mounting holes and the original Fuel Filler hole in the side with body filler (long term will fibre glass the area) then rubbed down and painted in Gloss Black to match the cover.



I drilled hole in the middle of the back edge of the Rear Panel and glued in the MSA Rain Light. The New Stop/Tail Lights (LandRover 90/110 generic units) were fitted by drilling a hole for the middle for them then 3 small holes for Nuts & Bolts to hold them to the Rear Panel. As the Rear Panel is FibreGlass I had to fit an Earth Cable to the lights before wiring.


The lights were wired back to a Weather Pack Plug to connect to the car loom once it had been wired and would allow the Rear Cover to be easily removed in the future.

[mscott]

MX150R Supercharging Project. Part 19.


Full Re-Wire time..


The day before I was due to take the car to Chris and get Tuned it was still in pieces, and the weather was very wet. In the end I ended up emptying as much as possible from my Garage, pushed the car in Front First and stuck a large Tarpaulin over the car and garage door to try and stay in the dry, not the best but better than the “Wet” option.




The plan was to make this Service Friendly and easy to work on in the Paddock, plus hell just clean and simple. I planned to split the Engine Harness to run Above and Below the Plenum chamber in separate looms and the Chassis Items (Lights, Fans, Transponder etc.) run around and along each chassis rail.


This was going to be fairly easy as I already had the ECU Engine harness (Above Plenum Harness taken care of) from the original SC install so I really only had to worry about:


Starter Motor


Alternator


Oil Pressure Sender


Dash Temp Sender


Cooling Fans


Lighting


Race Transponder


Dashboard


Fuel Pump


Easy when you say it fast, but in reality it was. I bought enough wire for each circuit/device keeping them in the correct Mazda Colours.


Vehicle Wiring Products will sell you a Metre of cable at a time, or quantities if needed in the Main Colour you need with a Trace Colour if required which allows you to keep the wiring simple and follow the Wiring Diagram in the MX5 workshop manuals.


I started with the Starter Motor & Alternator first as they have large capacity cables so get them out the way first. I took the Main Current Output from the Alternator to Main Feed side of the Starter Motor along with the White/Green smaller wire (needed to Excite the Alternator), then the Alternator Warning Light, Oil Pressure Sender and Starter Solenoid wires were connected to colour matching wire and fed through the firewall in split conduit (tapped up every few inches (lots of cm for Metric guys)).




Now that’s out the way the Inlet Manifold can go back on and the Top Harness “Plug-N-Play” style went straight back on and the wires again through the firewall to the dash. The Front Lights, Cooling Fans and Race Transponder were all installed in a similar fashion around the outside of the engine bay. All joints were first Soldered then covered in Heat-Shrink sleeving. Items such as the Cooling Fans etc. were connected with Weather Pack style connecters.


Please,,, I don’t want to get into the whole debate on Soldered vs. Crimped, I’ve used both in the build and as long as they are done well and not at a Stress Point they shouldn’t fatigue or break (which so far they haven’t). It’s all about common sense and application.


The Rear End was next part to get wired. The Rear Panel was wired so it could be simply removed if needed. This was done by wiring the Rear Lights to a Weather Pack Connector that come out just above the Battery Box. The Fuel Pump and Fuel Tank Sender (for what it’s worth) were wired and fed through the Rear Bulkhead by the Battery Box and all the Rear End wiring including the other half of the Weather Pack connector for the rear lights was fitted inside the Split Conduit that runs along the Transmission Tunnel from the Battery Box to the Centre Console. Along the way I picked up the Handbrake Warning Light as it’s only 1 more wire (excessive I know but at least when I’m on the Grid waiting to start a Race I’ll know if I’ve left the Handbrake on, its happened to people I know).


The Brake Switch and Dash Binnacle were then wired as it was a simple job of circuit by circuit, wire by wire joining the wires, crimping connectors to connect to switches or fuses as required. I added a second fuse box to run the Car Circuits as the “Engine/ECU/Fuel Injection System” were already covered from the original install. Each Ground or +12V connection made were labelled to make life easier in the future.




The centre console was the last part to be connected. The only addition I had to make was to add a Switch for the Front/Rear Lights as originally these were controlled by the Indicator Stalk that was removed with the original harness. Once completed it was powered up and all the body circuits worked first time, bloody good job too as I’m and electrician and run my own installations business for my second job (got to pay for racing somehow).



Being as its now early hours of the morning I’m off to bed, tuning day tomorrow afternoon and I have to go to work in the morning, what was I thinking, but there’s not much left to do before starting it.

[mscott]

MX150R Supercharging Project. Part 20.


2nd Tuning Session..


I finished working at lunch and shot home, a quick change of clothes and back out to the car, at least it wasn’t raining. There were only a few things to do, Oil, Water, SC Drive Belt, Newly Painted Cam Cover etc., New Spark Plugs, temporarily connect the engine cooling fans (they were chassis wired but didn’t have time to fit the Weather Pack Connectors) and oh yes, Petrol…




A quick once over and moment on truth, Master Kill On, ECU/Engine On, fuel Pump Run for 2 seconds then shut off as designed. I ran a quick check on Tuner Studio on the Laptop, all looking good but to save time I ran the Fuel Pump from inside Tuner Studio for around 10-15 seconds to purge any Air out of the system.


Moment on truth, check in Neutral, Push start button. Started first time, no seriously it did and a good job as it needed to be loaded on the transporter about 20 minutes ago. Quick trip up the M6 to Chris @ EFI-Parts for hopefully a good result would follow.


We strapped the car down on the Dyno, Chris was much happier with the New IC install and started to tune, but quickly stopped. We were getting Knock again and the AIT was high again. I got Chris to do a quick run and noticed that the By-Pass Valve wasn’t opening when he came “Off Throttle”.




I remembered reading on a build blog a long time ago that I had read about some people who run Dual Throttle Bodies had to take the By-Pass Vacuum feed from the Plenum, this made sense whilst I was watching the engine running, Throttle Off, no vacuum past the Throttle Body on the Plenum meant little to no vacuum on the SC Bypass. We stopped the run, re-plumbed the By-Pass Valve using a Silicone Hose from a spare Bung on the Plenum and blanked the original Vacuum feed off and run the care again, Bingo it now was opening properly.


AIT dropped massively and the Knock problem went away, only job now was to tune the care. The end result was a little disappointing (nothing to do with Chris’s efforts or abilities, far from it, just the way it was) and the End Result was 177BHP at the Flywheel, however it was stable and safe. A long discussion followed the tuning session and the consensus was that a Reduction Pulley with a sensible % reduction should get the last few horses back under control, but as I had a Race Meeting @ Cadwell Park in a week’s time it would have to wait until after that.



I took the car home feeling much happier, just needed to fit the last few wiring connectors, put the Nosecone back on then it should be good to go.

[mscott]

MX150R Supercharging Project. Part 21.


1st Race After Re-build & SC Reduction Pulley Fitting..


Quick one this, all was good, just needed the few extra horses as the other MX150R’s had an advantage and on the straights pulled away, other than that all worked well, in fact it never missed a beat.


Next step is to fit a reduction pulley. I read up on the recommended pulley sizes and decided to go with a 15% smaller than stock. Any smaller and I’d run the risk of the belt slipping due to lack of surface area of pulley to drive belt.


I purchased a KAVS pulley (ironically it cost more than the SC originally did !) and set about fitting it. Now if anyone has done this you’ll know that the Stock Pulley can be a pain in the arse to remove, you can buy specials pullers but that seems excessive for potentially a “1 Shot Deal”, other people have ground them off (and damaged their SC shafts in the process).


I decided to make a Pulley Removal Tool. 1st drilled an 18mm Hole through a scrap piece of 12mm plate I had left over from the SC Front Mount, I then Welded a 16mm Tow-Bar Bolt Fixing Nut onto the plate over centre of the hole.




Next I removed the plastic bung in the end of the SC shaft and threaded in an M8 Bolt. This was to give me a sacrificial surface to push against. Next step and done quickly was to weld the SC Pulley to the 12mm Plate. I welded this as fast as possible as I didn’t want the heat soaking through the SC shaft and damaging the Nose Seal on the SC.


As soon as it had welded it completely I used my Air Impact Gun on Maximum to wind the Tow-Bar Bolt into the M8 bolt in the end of the SC shaft. It took about 10 seconds and off it came. Job sorted.




I next fitted the collet (back part) of the KAVS pulley onto the shaft then bolted the actual pulley part to the collect but something didn’t look right, dumbass! I had forgotten to take the M8 bolt out of the shaft. After pulling the pulley apart and removing the bolt I again reassembled the Pulley and this time it fitted where it should.



Last thing that needed doing was a change in Drive Belt size, not a major issue but at least now I can get a Gates 4PK belt to fit.

[mscott]

MX150R Supercharging Project. Part 22.


3rd Tuning Session & Next Race..


The 3rd Tuning session was a quick one, Chris did his magic and in a relatively short period of time the car was now at 203.7BHP at the flywheel. I’ll buy that for a Dollar!




A quick test drive and, oh yeah, it’s fast as… You know what that rhymes with Duck!


The next race meeting went well, qualifying went well.


Before the 1st race as normal I filled up the car with petrol. So much easier now having a top mounted filler, and as with all good racers weight is an issue so I only put 15 litres in which should be sufficient for the race.


Race started and all went well until around 3 laps in, something happened and for a few seconds I thought I’d blown the engine. It hadn’t lost any power and each time I came around people were sticking fingers in their ears.


I carried on racing until an old Gremlim I had last season re-appeared. On Hard/Fast Left Hand Bends I was getting fuel wash, i.e. No fuel being picked up by the Fuel Pump (I had previously tried Fuel Foam in the tank but this didn’t stop the symptoms).

This was no fun as when the fuel then was picked up, because the SC is still being turned by the Engine/Drivetrain through the car moving I was getting my head thrown into my seat.


Race over I was pulled over at the end of the Pit-Lane by the Scruitineers and had my Race Pass taken off me until I got my car fixed, on the way back to the Paddock I was going through Parc Ferme I was asked by the 750MC if they could put my car on their dyno just to test the Dyno, I said yes but then the Scruitineer who had pulled my Race Pass came over and started having a go about the noise of my car.


Whilst he was arguing with the guy from the 750MC about the noise I noticed all that had happened was the Silencer had blown out of the downpipe, I pushed it back in, started the car and the Scruitineer was happy. Quick power run and the 750MC dyno showed 200BHP so not a million miles away from Chris’s, allowing for the fact I’d just raced it for the last 15 minutes wasn’t that bad.


Back to the Paddock and a New U-Bolt was all that was needed to fit the issue. Took the car back to the Scruitineers and got my Race Pass back for the 2nd Race.


I filled the car heavy for the second race, at least I wouldn’t get fuel wash but the weight was an issue.

This needs to get fixed..

NOW..

[mscott]

MX150R Supercharging Project. Part 23.


Fuel Surge has to stop..


The simplest way (say anything quick enough and you’ll start believing it) to fix this is to fill an External Fuel Swirl Pot.


The Swirl Pot will hold 1.5 Litres of fuel and as the outlet is at the bottom no matter how hard you corner the fuel will never fail to be able to come out.


Plumbing description of the Swirl Pot:


The Output from the In-Tank Fuel Pump goes into the Swirl Pot.


Bottom outlet of the Swirl Pot goes to an External Fuel Pump Inlet.


Output from the External Fuel Pump (through a High Pressure Fuel Filter) to the Fuel Rail and Injectors.


The Return from the Fuel Regulator/Fuel Rail returns to the Swirl Pot.


The Top of the Swirl Pot returns to the Fuel Tank where the original Fuel Return went.




So as the In-Tank Pump only has to fill the Swirl Pot.

If the In-Tank does ever get Fuel Wash the Injectors are still being fed by the 1.5 Litres of fuel in the Swirl Pot.

As I’m not planning on doing a “Wall Of Death” in it then this should fix the problem weighing much less than the Heavy Fuel option.


Parts Needed:


Swirl Pot - eBay


High Pressure Fuel Filter - eBay


External Fuel Pump - eBay


Fuel Pipe, Jubilee Clips, Pipe Reducers, Wire & Connectors - Vehicle Wiring Products


I started with the intention of fitting the Swirl Pot on top of the tank at the rear but it quickly became obvious that it wasn’t going to fit. Looking around I couldn’t see where it would go.


A bit of head scratching later and I realised that it should fit if I was to trim the Bottom Mounting Plate of the Swirl Pot leaving 2 of the fixing holes in place.

There was just enough room to mount it at the front right hand side of the tank. A quick slice and dice on the band-saw (no chance of a refund now) and it was chopped.


This was going to work well as I could mount the External Fuel Pump on the left hand side and plumb the Swirl Pot outlet, into a reducer then in the Pump bearing in mind it has to be a Gravity Feed. Now how to mount it all?




The simplest method was to make a couple of other brackets that would bolt to existing holes in either side of the fuel tank, from these brackets I was able to then mount the Pump & Swirl Pot. The Fuel Pump Bracket also mounted the High Pressure Fuel Filter as this saved on working out “How and Where” to mount it.



The rest of the Pluming was simple and just involved moving the existing pipe work around to suit. All the Rubber Hoses were rated for Fuel Injection Pressure. I spliced the +12V & 0V for the In-Tank Pump and wired this to the External Pump.

Time to test.



I primed the fuel system through Tuner Studio by turning the Fuel Pump Relay “On” and ran for a couple of minutes, no leaks so all appears good. I started the car and to test it I un-plugged the In-Tank pump connector, the car ran with no problems as it should, after all the External Pump was now the one needed to run the car, effectively the In-Tank Pump is only used to “Top-Up” the Swirl Pot.


A hole was drilled in the top after carefully measuring where the Fuel Cap would be, then the edge of the FibreGlass was painted to match, now Re-Fuelling is a breeze..

[mscott]

MX150R Supercharging Project. Part 24.


Where to go next,,, Turbo or Over-Size Crank Pulley ??


The car has now been run for over a year since the Engine Swap and IC Install.


I took the car back to Chris @ EFI-Parts and had a quick Dyno check done. He made a couple of small adjustments, nothing major and the car made just over 200BHP at the Flywheel.


Not bad for a “Home Brewed” SC Install and as the car has been raced for the last year, done a few Long Track Days and since the fact that the only difference is 3BHP I’m happy. Chris said it could have been down to so many factors that it wasn’t even worth worrying about, and I’m not.


Option 1: Moving on, the only way I can see of getting more power from the SC is to change the Drive Ratio. I don’t want to risk a Smaller Reduction pulley as that will likely slip, plus the Pulleys cost more than I paid for the SC.

The other option is an Over Sized Crank Pulley, however this is where I’m undecided. If I get an Oversized Machined Crank pulley will it cause any issues as it won’t have any damping in it? Stewart has been running a Solid pulley all season so I’ll watch this space.


If I do go for an Oversized Pulley there is a limit to the efficiency of the M45 SC and if I’m not careful at high revs I’ll just be over-working the SC and not gain anything.


Option2: Turbo Time. Stewart is looking at getting Kits made for the MX150R (Exocet). This may be the way to go and I believe he should have a working car hopefully by the last race of the season at Donnington (Deja-Vu).


I’m currently writing this as I’m not racing whilst waiting for a Shoulder Operation, so I thought it would be a good time to publish this Thread.


At over 11 thousand words and countless pictures, it at least keeps my mind of not racing and reminds me that “I Can Do That…” “I Did It...”


If there are any questions that you would like answering or anything that doesn’t make sense then please message me (I did do all this over a year ago so the content is mostly from memory and my iPhone Photo Library.


If you wish to see what I’ve done in person or pictures of anything in detail then feel free to ask.


Thanks for reading, Regards Micky…

[phocup]

[davetherave]

Thanks Micky for this post some very good info

[gbob]

Great read and great skills on fabricating and welding all of the required parts. 👍🏼

When you are talking about turbo'ing the car, are you removing the SC or are you adding the turbo to twin charge it?

[mscott]

Are we talking about an MX150R / Exocet or the T.A.R.D.I.S. ?

Being serious for a second we are looking at running just a Turbo instead of the SC. 

However nice it would be there just isn't the practical space to fit both "Under" the bonnet and the only way I think that could even be possible would to build the SC into the "Plenum/Intake".

If such an Animal every existed (you can but only dream) it would probably be over BHP/Ton limit for the 750MC Sports Specials so other than a Track Day Weapon,,, ah that's got me thinking now,, stop it.....

[miatagr]

Nothing but respect for your skills and dedication but might have saved some time and trouble to buy the kit from Fast Forward Superchargers in Phoenix.

[gwnwar]

Great write up.. Have you seen this crank pulley from TDR It overlays the OEM pulley.. go from 130 to 150mm

trackdogracing.com/crankoverlaypulley.aspx

TRD also makes a pulley to replace the OEM not to go over, same size as OEM.. if you order get the right one..