Twin Seq. Dry sumping for beginners :D

[oakey]

^ What happened down by the sill area dude? I like the 2tone though Good effort!

[Turbo-Brown]

Should point out that that one is scrap!

What happened was I gel coated the mould for the blacked out margins, and then put the carbon in once the gel had gone tacky, thinking I could still manuvre the carbon around.

What happened was that the tacky gel grabbed the carbon and wouldn't let go so it all got torn to shreds

Live and learn, expensively

Still, it's good to see how light the finished product will be!

[Speedtouch]

Surely not scrap? Must be of use to someone on here I'd imagine, as a Tech 2 trim would cover the manky area nicely...

[gareth]

a Tech 2 trim would cover the manky area nicely...

they normally do as standard afte a few years!

alex, the black and carbon looks awesome!

[Turbo-Brown]

The grot on that wing goes further than just the lower bit unfortunately

Had a measure up of the volumes of cylinder and head today. Interesting findings!

Started off by setting No.1 piston down in its bore. Did this by zeroing the depth probe on a digi-vernier on the glass plate in the photo when the piston was at TDC, then rotated the crank so the piston was about 10mm down the bore. It occured to me while I was doing this that the measurement was important, not the 10mm, so 9.24mm was it




Gave the piston a bead of vaseline to stop anything leaking past it:




And also sealed the glass to the block with a smear of vaseline. Also checked that the deck was level with a spirit level:




Finally measured the volume with a syringe and some meths. Any inert fluid would do though.



Did the exact same thing with the cylinder head too:




All the results were recorded on these bits of paper along with the workings:







Looks like not only is the compression height wrong, so is the compression ratio! If I bring the effective deck height up to where it should be, the CR is 8.2:1.....when I ordered 8:1!

Turns out the 2.3 option is a non-starter too. It would give a 6.1:1 CR which is a bit on the low side for my liking

Also made a start on boot lid two this weekend! Decided not to mess about with cardboard as the basis for the mould, but instead to make some sacrificial fibreglass hems. Thing this should work nicely, hope it does anyway as it takes aaaaages to hem things up in cardboard!

[Speedtouch]

Had a measure up of the volumes of cylinder and head today.

Your own photographic evidence would appear to disprove this, suggesting that in fact, you did this back in December of 2008 - you can't fool us that easily

[d6dph]

Haha so he can build a hell of an engine but technology is a different matter

It's coming on well Alex, I get the feeling that it will come on leaps and bounds all of a sudden. Keep up the good work.

[Turbo-Brown]

:LOL: I really have no idea how to change that date! Be nice if I could turn it off actually!

I'm feeling alot more motivated to get the engine built now that I know the CR is within the realms of realism.

Question is, decomp plate from the UK, or thicker MLS from the US!

[Chuntington101]

i say decomp plate! but get that thing o-ringed on both sides. that should make sure you have no sealing problems! lol

Chris.

[Turbo-Brown]

Ooh, random chance has suggested a possible solution to the HG problems!

The crank from the M51D25 has a stroke of 82.8mm which would drop the piston down by 0.6mm at TDC.


So the 'head vol is 40cc

The pistons add 12.6cc

The 0.6mm lower gives 3.4cc

The HG gives 10.1cc

and the swept vol is 469.8cc

Clearance vol is now 66.1cc

CR=(66.1+469./66.1=8.1:1 with no super thick HG to worry about.

Hmmmmmmmm!

[e30_Turbo]

Nice! I was wondering if you could recover the lost cr by some head work? I've seen some quite awesome head jobs where loads of material has been removed, with the volume your needing to remove, would you think there's enough to remove safely tho?

[e30_Turbo]

[gareth]

M51 crank... hmm. Would that be stronger too being diesel? Could be the perfect solution then

I know a lot of diseasels have steel cranks

[Turbo-Brown]

Given their tendency to crack, I'm a bit reluctant to spend any real time or money on the 'head to be honest!

The M50 cranks are all forged steel I think, it's really just the stroke that I'm after.

I'm carless at the moment as the Civic is having it's timing belt done! Took the opportunity to start work on the headgasket for the Touring I've had for the last 6 months, and also slot some other work in:

Boot lid is nice and shiny now from this:




To this:




And while the inlet's off of the touring, started making this for the throttles which I made for Brown a few years back:

[Turbo-Brown]

Gleee!

Think I've found a crank for about £75 or so.

It's cheap enough to take a punt on, just to see if it fits in the block and whatnot.

[cplagz]

I do hate you. Hah, I wish I had half the skill you do!

When are you going to start producing CF for the masses ;) ?

[Turbo-Brown]

cheers dude Almost every time someone asks for something in CF, they say it's too expensive though

Gleeeee, the new (old) crank is paid for!

Just gotta get it through and I can start stripping the block......again.

It's no bad thing really as I wanna chamfer the bottoms of the bores, just to make sure the pistons don't catch, but I'd assembled the engine before I thought about that which disinclined me to do it. Having to strip everything down means I can do the job properly though!

[gareth]

you're just a tinkering addict aren't you!
what will you do with your time when this is finished? start again with yet another variant of forced induction? twincharged with a homemade blower and turbo?!!!!

[Turbo-Brown]

The bottom of the bores thing has been bothering me for ages, but not quite enough to take everything apart again.

Think I'm gonna be a bit happier if I do the job properly though

Woo hoo!

Crank arrived today, had a quick measure and the stroke is just what I need (always pays to measure things yourself!)

A very quick inspection suggests that it's in better nick than the M52 crank in there already too.

It's come from an automatic by the looks of it so it shouldn't have been over-revved.

Fingers crossed that the Plastigage I've ordered arrives by the weekend so I can double check the bearing clearances before putting everything back together

[Turbo-Brown]

Two slight setbacks to the engine build this weekend:

1) The crank needs a re-grind. Closer inspection of three of the mains reveals some corrosion where presumably the engine's been stood for ages.

2) I scratched my eyeball on saturday night so I could barely see on Sunday

[gareth]

2) I scratched my eyeball on saturday night so I could barely see on Sunday

was this an attempt to broaden your horizons for a night on the pull?

[Turbo-Brown]

should've said "scratched my eyes out"

[Turbo-Brown]

Don't suppose anyone knows how much (or even if you can buy) an fuel only Megasquirt it do they?

Had a thought the other day about the electronics to control the valves in my system.

They definately need to be mapped, rather than having a linear response. They also both need to be moved dependent on the pressure at the outlet of their corresponding turbo so I need two MAP sensors.

Also, there will be conditions, such as high revs, where the valves will need to be fully open regardless of pressure so a rev dependancy is also required.

All this leads me to think that a mappable injector controller would do the job nicely, one per valve.

Don't need anything other than that in the box of tricks, just a MAP and REV based PWM output.

The main ECU can control the external wastegate based on pressure in the manifold.

Any ideas on suppliers and prices?

Cheers!

[m_jermyn]

What?? Far out man speak english, lol

[e21Jason]

The clue is in the title "squirt"

MS was fuel only to start with spark added after so fuel only is okay, you could use VEMS and program the spare injector outputs to do the valves.

Jason

[bigbhpwannabe]

this is 1 rude project ,supercool

[cplagz]

Alex - have a look at the MicroSquirt. DIYAutoTune are also in the process of building DIYPNP, which is basically plug and pray MicroSquirt for the 55pin Motronic.

You could also look at running something like a S-AFC but for MAP not AFM .... no?

[Turbo-Brown]

The microsquirt did catch my eye, but they're $400 each rather than $140.

Literally all each valve needs is a PWM output based on revs and pressure at some point in the system.

Unfortunately each valve needs to monitor the pressure at a different part of the system so multiple MAP sensors are required (probably use multiple crank sensors too for ease!)

The engine management will still be taken care of by the Emerald, and that'll control the boost of the larger turbo based on manifold pressure.

[e30_Turbo]

Have you asked if DW can mod your emarald to do it all?

He makes alterations for customers all the time and your adding more of the same functions to it, makes sense to keep it all in one box

[GeoffBob]

Adaptronic will also do what you are asking. 'Has a handful of extra PWM outputs that can be configured to respond as a function of the usual inputs (MAP, TPS, RPM etc) or any linear combination thereof. Expect to pay close to £600 though.

If you're keen to construct something entirely standalone (little-black-box) with its own RPM, pressure and TPS inputs, I'm pretty sure it could be done with a handful of LM358 Op-Amps and two TL494 PWM controller IC's at a total cost of around £4.25 (excluding any additional sensors you may require on the engine, obviously).

[Turbo-Brown]

Well, I talked to Emerald about it and they said they might be able to sort something out.....and then whenever I tried to ask them again, they just ignored me or said they were too busy when I spoke to them on the phone.

To be honest, think the fact that I need three different pressure monitoring points is what causes the problems. The Emerald has enough PWM tables to do what I need, but only crank speed and one other load input so it's not much help for anything other than overall wastegate control.

The trouble I'd having with doing something from scratch is knowing where to start, and also the interface needs to be easy to use and visualise what you're doing as there will be lots of setting up to do, so having a 'map' of valve position against pressure and crank speed rather than just a list of numbers in some code will make life easier....I think.

For a couple of hundred quid that a pair of MS1 units cost, I think it's gonna be worth having the backup of the MS community etc rather than treading my own path.

[e30_Turbo]

Do you know Phil Ringwood?

He builds ms's and writes the code for them, I have contact details if you need

http://www.extraefi.co.uk/

[Turbo-Brown]

Aah cool! I don't know him but it might come in handy! I'm pretty convinced that a revs and pressure based control for each valve will do the job though

Well, what a relief! After months of agonising over how to solve the piston issue we're pretty much back where we started!

We've gone from this:



to this:



which is the piston sitting 0.6mm lower in the bore at TDC. I'm really keen to get on and sort the 'head out now so I can get the engine built

Picked the crank up today and have progressed from this:



through this:



to this:





Gonna start on the 'head tomorrow, and also start machining away the bits of the sump I don't need anymore if I get time.

Wish me luck, got a date too! eep!

[gareth]

Wish me luck, got a date too! eep!

weyhey! don't invite her to your place to cook her a meal in 'that' kitchen just yet though....

[Turbo-Brown]

noted!

Managed to drill the remnants of the long inlet stud out today.

Made a strap to hold it down to the mill bed:




Shimmed it up until the face I wanted was level:




And then drilled and tapped away






Also made a start on cleaning the carbon out of the chambers!