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ROLLING ROAD DAY - DSAUTOMOTIVES 31st MAY

Jon and Nathan

Thanks for the input. The guys at DSA were a bit hit and miss (the only thing they adjusted was the on-boost fuel pressure ... until we had so much fuel the engine bogged down). They spent more time bolting and unbolting parts than actually tuning anything. All I ended up was £300 lighter to end up where I started!

With the US fuel-head and adjustable WUR I agree we should get enough fuel, but this is beyond me alone. I know that Bob Watson has also struggled to set this up - so it clearly is not a simple job! I would like to hand it over to someone that knows what they are doing and get it sorted. Any contacts who you know are able to do this most welcome.

I have contacted GTART in Brighton who seem to think they have both CIS and EFI solutions (and very respected in their field). I will go there and talk it through with them to see their solutions. I have researched EFI system that use modified fuel blocks to take EFI injectors so the system retains the original IC etc to keeop cost down.

Jon - please let me know when you need the pistons/barrels and the fuel head.

cheers Simon
 
I think Bobs approach when he tried to set it up on Marks car was a bit hit and miss too, if he had contacted Brian Leask and told him what modifications had been done he would have advised what each setting should be. First with the system pressure set to say 95psi and with the electric disconnected from the WUR and it being cold you should have Xpsi control pressure, then with the lead connected and the WUR warmed up you should be at Xpsi control pressure, then wind the boost enrichment threshold to it's highest setting to help get rid of as much of the rich mid range as possible, Then add 1.2bar to the WUR using a Mityvac and you should have Xpsi.
You then have a baseline, put it on the dyno and see what the afr/lambda is like on tick over and adjust accordingly to get the right setting, then go though the gears on the dyno without getting any boost and adjust accordingly, you should be aiming for 14.7afr or 1.0 lambda. Then do a normal pull and see where the fuel goes on boost, you will no doubt get a rich patch where the boost enrichment starts but you are looking for it to lean out to 0.8-0.82 lambda or 11.8-12.0 afr up at the red line, if it's still not rich enough then keep adjusting the boost enrichment setting until it's maxed out, if it's still not enough the try raising the system pressure again until it is. If you have the system pressure at 100 psi and the WUR adjusted to its maximum setting then you actually are out of fuel.
When you raise the system pressure you will have to reset all of the settings on the WUR as it will affect them, apart from maybe the boost threshold adjustment which will no doubt need to be set at its highest setting regardless. I'm not certain what the afr/lambda setting should be on tick over, it's something like 13afr but you need to check, the cruise should be like a normally aspirated car at 14.7afr or 1.0 lambda, then on boost it wants to be 11.8afr or 0.8 lambda. When you have all these settings then you will need to address the rich mid range which will require the solenoid valve to delay the enrichment threshold some more, you will always be richer in the mid range than you really want but it's about finding a compromise, and with CIS it will always be the case but you should be able to get it acceptable.
You really can do all this at home with the right equipment, it shouldn't be difficult Simon, and like I said in an earlier post it would be a good idea to get the Innovate stuff anyway so you can see what it's like in summer and winter, and you can keep an eye on everything on track days when everything is hot and being worked hard. The CIS gauges are peanuts.

I could do with the P&C's ASAP mate, the fuel head isn't as important if you need it for testing but if not please send it at the same time. My motor is up at Fearnsport being mapped again, fitted a load of new sensors which made it run all weird so it's being tweaked, hopefully it will be sorted out this time, fingers crossed.


In the pelican link I posted above have a look at JFairmans post on page two, he mentions how much the AFR can be changed by raising system pressure. It's about 13 posts down page 2
 
+1 on what Jonathan wrote.

Jonathan, are you aware the P's & C's are marked for different weights/sizes. I'm thinking you were going to try and use Simons on your engine. Hopefully they are the correct match for you.
 
All checked and sorted Nathan, they are a perfect match [:)]


ETA: The main difference is the height group, they are usually group 5 or 6, the number is in a small triangle on the bottom on each cylinder, Simons and mine are group 5, which are apprently the most common. You can apprently have group 5 on one side of the engine and 6 on the other. They would equal out the same, i'm told.
 
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