www.RX7fb.com

As most of you know, Rexanne is my 1984 s2 Rx7 project car.

She came to me last year looking pretty sorry for herself....





Then spent 9 months in the garden, with lots of this...




And now looks something like this...






She's now been on the road for a few months, and done about 6,000 miles, and it's time to edge towards the next steps of her upgrading! With the chassis and handling sorted to a degree I'm happy with for now, I'm left with two areas of improvement to think about.

One is the interior, which is on hold for now. I've got a nice fixed back bucket seat sat in my room, but to fit it right for me will require quite a lot of work. I will also need a harness to make the seat safe and harness bar/half cage to mount the harness to. Overall it's lots of effort and lots of £££ and I'm not quite sure what I want really. So it's on the back burner simmering away in my mind!

This leaves the second line of attack to take centre stage. POWER!!!!

After months of indecision I've decided I'd like to go 12a turbo, with fuel injection. The end goal is about 240hp, hopefully on stock ports or a mild street port. I need the car as a daily drive, and economy matters to me too much to consider any more extreme porting right now. I know it's not necessarily the most sensible option, and its' probably cheaper and easier to drop a turbo II engine in and get that sortta power almost instantly but I kinda enjoy the 'making things' element. It's also nice to do something a bit different with Tim and Ramon's 1st gens already having the 13bt swap.

I plan to do this in stages, first getting the 12a running n/a with fuel injection and then sorting the turbo side of things. Just to be awkward, as usual, I'm currently liking the idea of mating some bike throttle bodies to a webber manifold, which will make a nice n/a set-up. The Suzuki TL1000R uses a nice pair of 52mm throttle bodies each with twin injector ports for standard size top feed injectors, all available second hand for about £50. Quite a bit cheaper than an IDA! Then I'll build a plenum for the throttle bodies when it's turbo time. I'll be switching to electronic ignition along side the fuel injection and running this all with a Megasquirt MS2 ecu.

First baby step is to get a new radio, and mount it in the glove box to make room for auxiliary gauges in the centre console. Then I'll get my oil temp gauge fitted and buy a wideband o2 sensor & gauge. Then I'll start collecting parts for the EFI conversion itself.

Money is quite tight at the moment (saving hard to be in a position to move out of my parents house) so this will be a bit more a slow burner. But I'll keep this thread updated with any progress, no matter how small

Great stuff Stevo, have you considered adapting a T2 inlet to it? It instantly gives you injectors and bosses, throttlebody and tps?

I know the bike tbs sounds pretty cool, not quite sure how you would mount them? You thinking Ida style downdraft? Individual runners? Need to ensure you get a clean map signal if you stick with it.

Either way, welcome to the world of rotary fi

those early photos remind me of last winter when we were all freezing our nuts off.... especially the grinding picture..... a few more weeks and we'll be back into it again!
When we see how good your car looks now Steve, it's easy to forget the long hours in freezing conditions that went into it.
I'm looking forward to seeing your engine mods.... especially as you're keeping the 12a.

.

Cheers guys

Yes it was blooooody cold last winter. Seeing as I have a fun car to drive as it is, I shan't be quite so driven to get out there in the snow.

RamoNZ wrote:Great stuff Stevo, have you considered adapting a T2 inlet to it? It instantly gives you injectors and bosses, throttlebody and tps?

I know the bike tbs sounds pretty cool, not quite sure how you would mount them? You thinking Ida style downdraft? Individual runners? Need to ensure you get a clean map signal if you stick with it.

I have considered a t2 inlet, and thats the back-up plan if I can't get the bike throttles sorted.

For the bike throttles at the moment I'm going along the lines of I'll build a adapter so they mount up to an IDA or DOCE manifold. Getting a clean enough MAP signal will require a bit of work. I believe MS2 can work in a mode where it uses a combination of MAP and TPS to work out he fuelling, which can be useful on engines with unstable map signals.

It will be an adventure!

Fun times ahead Steve, just for your information too as a side note to what Ramo said about the TII inlet-I'm pretty sure Tim has a JDM 12at inlet manifold at his place as another solution if the bike bodies don't work out. What are you going to do about fuelling? Swirlpot arrangement or maybe a snazzy in tank high pressure pump?

Calendar shots just keep pouring out of Steve's camera...... I can see how he holds his day job down.

captainbizzaro wrote:Fun times ahead Steve, just for your information too as a side note to what Ramo said about the TII inlet-I'm pretty sure Tim has a JDM 12at inlet manifold at his place as another solution if the bike bodies don't work out. What are you going to do about fuelling? Swirlpot arrangement or maybe a snazzy in tank high pressure pump?

That wont work Timbo, the 12at had only 2 injectors, both of which are mounted in the centre plate. The 13b had 4, but the secondaries are mounted in the manifold. To make 240bhp he can source 2 suitably sized injectors to suit and mount them in there quite easy.

Im sure the MS can also run 2 low impendance injectors if required, which opens up a full range of possibilities.

Aaaah fair do's.

Thank you Dave I'm getting to grips with my new camera slowly. I'm still quite amateur when it comes to still pictures rather than moving pictures but it's getting there!

Tim, I'm thinking swirl pot. I've got an in-tank pump set in the garage, but I figure without modding the tank lots it'll still struggle with fuel starvation on corners. Maybe I need to swing by one day and we can head to RX Motors and get Tim to raid the caves and see what useful bits turn up!

Ramon, indeed MS can run low impedance injectors Part of the change to EFI is to retain/improve fuel economy, so finding a way to run 4 injectors with pretty small primaries would be nice

Steve-A wrote:
Tim, I'm thinking swirl pot. I've got an in-tank pump set in the garage, but I figure without modding the tank lots it'll still struggle with fuel starvation on corners.

didn't the tank that Tool was selling from the injected JDM 12at have baffles in it ? You'd have to mod the spare wheel well like Tim did but that tank might solve the cornering issue