DIYEFI.org Forum

No shortage of database space for posts. Sorry about it, but I won't lose info to some rogue and it's non trivial to have more than one set of rules. At some point I'll try to configure it with a 5 minute window or something like that.

Coil: Try subaru, pretty much ideal for a beetle running wasted spark.



Re IAT, there is theory, and then practice. In theory yes, you want MAT + MAP to control things. In practice MAT is an utter lie due to sensor soak and airflow and radiated heat etc. In practice you want ambient air temp or similar. My idea to use the fan to keep the sensor close to air temp was based on this. Feel free to run a MAT and IAT and Ambient and post IC/pre TB etc. The more temp figures to correlate and model from, the better. But one well chosen place will work OK.

Ok, bought that.

Is MAT heat soak caused from proximity to engine conducting along intake? Thus it is measuring temperature of manifold instead of the air? I have some ideas of how it should work, but obviously no real experience so just trying to understand the why.

The family is away this weekend so should have time to work on the engine. I need to make a jig to cut a 100mm or so hole in the engine block and head. That is going to be a bit of a challenge.

All air temperature sensors are subject to getting warm in the same way that your car gets cold at night with a clear sky. Radiation. Without sufficient airflow over them, the radiant heat from the surroundings heat the sensor, and no air flows past to cool it. They almost invariably read a bit hotter than they should, and often a LOT hotter than they should, which is when you get trouble running the car at all. I'm looking to model this somehow, but still don't have data and a plan to do it right, yet. The net result is that if you hang your IAT out through the intake air vent so it's got plenty of airflow always, then it'll run your car better than if you tried to use MAT for air intake temp.

What's the 100mm hole for?

Fred.

Thanks for the explanation re: IAT vs MAT

What's the 100mm hole for?

Going from a 85.5mm cylinder to a 94mm one. 1584 -->1915cc

Take pictures of that, please! Sounds like a fairly extreme thing to do DIY :-)

Don't worry, I will!

You can buy a jig ready made a couple of places, including here: http://vwparts.aircooled.net/Engine-Cas ... g-tool.htm

I plan to make one myself...we will see how that goes.

And so it begins......

Put a bit too much solder on the MCP and I can't find my desolder braid. I'll have to go pick some up today.

New bigger pistons and cylinders

Tried to get the boring going, but went around in circles instead....and not in a good way. Nothing got done in that respect.

I was able to get the power supplies going on the Jaguar board, but when I started doing the MCP and other SMD ICs, I think I messed up. I put on too much solder and not enough flux...then had to buy some desoldering braid. I think I finally got the hang of it, but some of the pins on the ICs got bent. When I went to fix them, I'm not sure if some fell off and/or the PCB pads came off. It is kind of hard to tell since everything is so GD small. I'm not really sure how I'm going to proceed.

Today was just a bad day...I'm going to take a break and come up with a plan tomorrow. Ugh.

Pause. Can't post now, but will later.