Slow burn project- T1 Speeduino EFI

[Bruce.m]

Using a 7.89 fuel connector looks to be the easiest option. It is the right size for the original Honda O-ring. Printed a support collar for the O-ring and also a clamp assembly to hold the connector central, square & in the correct position for the seal.

Original part on the right side.

[Bruce.m]

Test fit successful. Locks the connector in position & supports the O-ring in place. It’s a bit bulky but isn’t heavy. Will be reprinted in nylon CF in due course to handle the temps in the engine bay.

[Bruce.m]

Small update. Had man-flu lately so limited progress.

Welded the O2 sensor bung in place. Definitely no photos of that as it’s MIG welded & ugly. It is airtight however so good enough.

A few more bits have arrived. Cohline 2240 fuel hose which is rated for nasty modern fuel, so should last. It’s 7.3mm ID (nominal size 8mm). That is the right fit for the Mex fuel pump, & the tank outlet I’m using (also the size used on Mex bugs & oversized 8mm tank outlets are available). The hose also fits ID6 quick release fuel connectors. These (in 7.89 size) connect to the fuel filter/ regulator and also the male fittings I’m clamping to the fuel rail.

[Bruce.m]

Realise I haven’t explained the fuel system fully.

Based on research & tips from the likes of PaulH. Bought a Chinese “Mex bug” fuel pump module which includes a mini sump housing so it works with the stock tank. Gives enough flow for a modest HP non-turbo engine. Easily sourced for less than £40 UK.





The fuel filter is a VAG item used on modern TFSI engines. It uses the 7.89 fuel connectors and has an internal fixed regulator at 3bar (higher pressure versions available), so does two jobs. I bought the Mahle brand version which is part KL156/1

[Bruce.m]

[Bruce.m]

For the crank trigger setup, I decided to “buy” rather than “make” to save some r&d time. Based in the UK I opted for PaulH (VWSpeedshop) set up using a stainless 24-1 hub and stock style pulley. I’ve read that Wally rates his so looking forward to that arriving very soon.

[Bruce.m]

Did some wiring over the weekend. Extended the Honda injector loom to reach across the engine bay. Also repainted the genuine underside tinwear pieces which are nos but the paint isn’t good enough to last.

[Bruce.m]

The crank trigger kit arrived from Paul (VWSpeedshop.co.uk). It’s a quality piece of machined product. Pulley tin needed some careful trimming to fit around the sensor bracket but with care the bracket holds the tin piece in place.

[Bruce.m]

[Bruce.m]

Checked my vw 106b coil pack & realised the 4 pin connector I’d source was a smaller version than I needed. I’d got 1J0973704 but the correct part ends 724 instead. That’s now ordered.

On the up side, it turns out the bolt spacing the coil pack is an exact match the the stock coil mounting threads. So with a pair of 80mm bolts it goes right on the fan shroud and I don’t need to make an adapter bracket.




Obviously the distributor is only filling the hole currently & might be left in place prior to a cam sync being substituted at a later date.

[Bruce.m]

Did a bit more wiring over the weekend. Made up right side HT leads and the coil connector. Need a few more parts to finish the left side leads.

[Bruce.m]

Fitted a Bosch coolant temp sensor under
#3 cylinder to read the temperature off the cylinders. Similar to the stock approach. The sensor is oem for a few cars & also Bosch Motorsport part so there is a good data sheet available with the temp profile.

[Bruce.m]

Bosch sensor part number is 0280.130.026 if it’s useful to anyone

—-Edit from the future—-
The metal body sensor was cooled by airflow in use so the reading was low. I replaced it with the plastic tip version as used for intake air temperature.

[Bruce.m]

Because I’m running J-tubes and not heat exchangers.. the tin underneath is not properly enclosed. This will mess with the stock thermostat operation and the temp sensor readings. I bought a pair of high quality “industrial tins” which are made from thick steel (available in stainless too). However the fit was terrible. The J-tubes also pass very closely under the cylinder head which isn’t great!

The usual method is to use exhaust wrap to enclose the pipe but I’m not a fan of the nasty itchy bandage!

So I used OEM style heat shield to do both jobs. This stuff is called “Nimbus” and you can see it under most modern cars. It is thin aluminium embossed sheet so easy to cut & form. I used the double layer version which has tiny air pockets between the layers.

[Steve Arndt]

https://www.awesomepowdercoat.com/industrial-shields