modded gt6

[DrKai]

Oh yh agree entirely the simpler the better and easier for me to make/ cheaper to have done. The lemans cars had tiny openings in the grill. But I want to get it aesthetically right then block it out internally/ split the air flow to use as a cold air intake 

[Clive]

You may want to experiment with a DIY windtunnel? John dod that a while ago I think, and seen elsewhere. Knitting Wool stuck various places and then use an airline to see how it behaves.All above my paygrade. I just cheat, use other peoples ideas and fit "foreign" mechanicals. 

[DrKai]

Got the engine on the stand. After decoking thrilled to find the pistons and bores in lovely condition and a deck height of 10 thou, so I'm going to leave the bottom end be!. Also ordered a super damper from the us, arp studs and some shiny chromoly pushrods, Burgess is nearly finished with the head so engine should be going together fairly soon. Baffling the sump is about the only other job.

[Clive]

4 hours ago, DrKai said:

 Baffling the sump is about the only other job.

Have you seen this thread elsewhere on the interweb?  http://sideways-technologies.co.uk/forums/index.php?/topic/7763-spitfire-sump-baffle-and-windage-tray/

Contributors include a chap who has raced a GT6 forever, another who hillclimbs, a vitesse racer of huge experienc and another who has a fantastic Vitesse (who thinks he has over-baffled his sump! be warned) Could be very informative, as some racers are very protective of their secrets.

[DrKai]

Clive that is fantastic. Really useful. I'm sure I'll be following that

Thank you

[DrKai]

Cleaned the block up but decided it needed a lick of paint. So stripped it and painted it in an epoxy grey I mixed up. 

Cleaned the mating surfaces bored and pistons.

Polished some alloy bits

Painted the starter

Super damper arrived from the US

In the middle of all that made a vanity unit out of railway sleepers

Also think I have the timing sorted now. If you're interested please see my woes in the engine thread and advise.

[Brooky]

I like the 60amp alternator, and the look of it too, Ill look for one of those when Im ready to do the mechanicals cheers

Like the look of pic 1 and 4 front spoilers, are you going to make it or have it made/printed? Quite fancy one for mine

[DrKai]

I'm hunting for someone that would be willing to make it from the drawings. Most places want something to make a mould from. If unsuccessful I'll have a go myself but will probably have to simplify it a bit but we shall see 

[DrKai]

Finished the flappy sump baffle. Made a new correct timing pointer. Received the remote oil filter mount, some sample fuel line and most importantly the beautiful jenvey heritage throttle bodies (yet to be photographed). Started to teach myself Tig for little brackets and alloy bits 

[DrKai]

Quick update while I've got 5 minutes. I'll take some better photos soon. Sump fitted. Head picked up from Burgess. Painted and fitted with ARP studs. I made a crank case breather out of some alloy and tapped it for an an10 adapter. Also drilled out the original rocker breather and Tig welded it over as I want to move it to the other side to neaten up routing to catch can. Made a bracket for the remote oil filter mount. Almost finished the crank position sensor mount. I drilled and tapped the front engine plate. Mount made of a plate with stand offs then another plate same radius as trigger wheel and the final little bracket on there. Will be a slot for fine adjustment. I'll post some proper picks when it's done waiting for some more threaded inserts for the ally tube as I butchered it so many times

[DrKai]

Some better pics of crank position sensor. Drilled and tapped front cover. Bolted a plate too it. With standoffs bolted to that through back side. Plate on top then bracket attached to this. All fully adjustable 

[mpbarrett]

That's very neat. Good to have some adjustment of the standoff between the senor and toothed wheel. if its a passive pickup coil the standoff is critical at low speeds otherwise the signal amplitude can be very low. This leads to all sorts of difficulty starting particularly on cold days. Had all sorts of starting problems with my EFI on my herald on cold days until I released the a gap was too large and the signal amplitude was very low....
Is there room for the fan/alternator belt or is it not being used?

mike

[DrKai]

Thanks Mike. That's what I was thinking. That and I didn't trust myself to measure perfectly the first time so wanted to be able to adjust for errors. The belt will only be there to drive the alternator as the pump and fan will both be electric so should be ample room for it

[JohnD]

Er, Dr.Kai?    Why not put the toothed ring between the damper and the pulley?   Else you will need to dismantle the sensor to change the drive belt for the alternator.

OK, you'll need a spacer on the alternator to bring the pulleys in line, but thinking on!

 

Also, make one of your pillars to support the sensor thicker than the other.     Any resonance that a pair could do will then be multiplied upwards, way out range of interference with the sensor.    I use a single pillar, but it's a shorter length of 30mm tube, welded to the bracketing, so extremely stiff and very high resonance (Ping!)

John

 

[DrKai]

Thanks John. In all honesty it's my lazyness. The trigger wheel I was sent by emerald doesn't line up with any of the pulley bolt holes as you can see in the pic. Really I should get a solid wheel to suit, drill out the bolt holes and shorten the stand offs accordingly. 

Good point regarding resonance. Adding a 3rd stand off alongside one of the existing should serve a similar effect? I have lots left over. Alternatively I could change the base plate to alloy and weld it up but then lose the reinforcement of the engine mount plate which I drilled to fit. 

[JohnD]

Kai,

Do you know https://trigger-wheels.com/store/contents/en-uk/d5.html?gclid=CjwKCAiA-f78BRBbEiwATKRRBMIfjzKVFEu1wY0w_N6OWVdk8IK6ivip4BVU8PuGfe_4bWYNbUcAsRoCOJkQAvD_BwE  ??  They are most helpful.

Your mount plate is secured by long bolts through tubes?    They should be welded to the mount plate, and to a base plate, as wide as possible to sit on your front engine plate, so that the whole mount is as rigid as possible.     Make the outer tube a wider tube - make both as wide as possible, but different - will  make it more rigid and I think any resonance will be too high to bother the sensor.    Shorter tubes, by bringing the wheel behind the pulley will add to that effect.   

John

[DrKai]

Thanks John a custom wheel from them should allow me to make it much shorter. 

Had a fun few days put the engine back in to allow me to start working on ancillaries

1st issue i forgot to put the clutch bearing in- no issue really as its going to have to come out when i swap the gearbox over. 

1 side mounts bolted up fine. Couldnt lower enough to bolt second side on. No amount of wiggling helped. Heartsink moment when finding the culprit. The new larger damp was resting on the steering rack. After much teeth sucking it seems the only option is to drop the rack down be re-fabbing the mounts. That's no issue but clearly it will affect bump steer horribly with it already being bad on a lowered small chassis. After much googling new plan formed to correct by replacing the rod ends with high angularity rod ends and mounting underneath the arms as per image. The will require either a tapered insert to the steering arm or reaming it out straight.

iI've also been working on the cooling system. As I'm replacing the mechanical pump with an electrical one I needed to make an adapter plate for the block. The easy way to do this woould be some alloy plate cut to shape and weld on some barbed hose with the end persuaded to the right shape. However I wanted a neater solution and to be able to mount a swirl pot/ header tank immediately infront of the take off. This coupled with the need to cross over the paths of the hot and cool side led me to go completely OTT with designing something new. 

I took a tape template of the flange, traced this on to the pc with a graphics tab, imported it in to autocad to be able to trace the rough shape.

 

Printed the flange alone to ensure correct and had to go through a couple of iterations to the opening and hole centres right. Once this was right I built the full model. My plan was originally to get it CNC milled so drew with this in mind however it quickly became apparent that this would leave quite narrow passages and a restriction to flow I wasn't happy with. I redrew with 3D printing in mind and submitted for an online quote. The cheapest of which was 1000 GBP. Thought I'd wasted a days work on CAD but persisted and eventually found a material called ultrasint which is a mineral infused polyamide and very strong, waterproof and highly temperature resistant at a much more sensible Price. I've attached some pics of my final design below along with the data sheet for the material. The play will be to replace the bolts with studs place the block on then a plate. The plate will allow even pressure to be applied and give a mounting point for support bracket for the swirl pot. 

 

 

 

 

 

 

[JohnD]

If I may. Kai, you can shorten the steps to take the shape of the front face of the head (or anything else!) by the 'dirty thumb' method.    Lay your paper over the surface to be copied, and rub a dirty thumb over the paper.  This copying tool is readily available in the workshop, but a soft pencil will do as well.    The edges show up beautifully, and may be drawn out at leisure later.

And, since you have gone to the enormous trouble, with great skill, to design a take-off plate for the collong sytsem, why have you left it so knobby and angular internally?     The outside is nicely smoothed off!   The coolant must flow through two right angles on each side, and then enter a circular connector.     Could you not have faired the internal walls as well?

I know, here's me in my armchair,  'advising' the guy doing the work, but that's what I would do!

JOhn

[DrKai]

Good point on dirty thumb trick

My first go had a beautifully smooth path by lofting a gradual transition between the port shapes, but it resulted in a couple of places of quite reduced cross section for flow. This could be solved by increasing the thickness but this would remove a lot of the elegance and make packaging more difficult as I want to add the swirl pot to the front. Having examined the original pump I think this still represents a vast improvement in flow. This design will also keep the cost of the print down as it allows 3mm wall thickness with minimal solid areas. Having a smooth path inside will vastly increase costs as this material must be printed by sintering therefore enclosed spaces must be printed solid as the unsintered powder would have no space to escape. As its a specialist material the majority of the cost is in the material rather than the process. Similarly printed nylon would be a third of the cost. I have test version on my cheap PLA printer as we speak I'll test it before use and see how the flow is but I'm confident it will be fine as the pump I have is a monster being capable of flowing  150l/min @ 0.85bar. (this throws up another issue as it consumes 30A at full chat so I think that 60A alternator is going to need upgrading)

Having said this it still hurts my eyes every time I look at it!

[JohnD]

Kai,

Have you watched the Project Binky videos?   Not Triumph but the transplant of the engine, drivetrain and suspension of a Toyota Celica GT-Four into a 1980 Mini.     Maybe not to your taste, but inthe latest episode, they fit an electronically controlled fuel pump, that responds to demand, reducing drain on the electrical system.       That demand is multifactorial, whereas a similar control of the water pump could merely depend on temperature, and be more sophisticated than just a thermostat.   See here, at 22minutes in: 

 

 

[DrKai]

I absolute love project Binky and Devour it every time there's a new episode. Oh to have niks engineering ability. It has been far too long since a Binky although the escargot and c1 have been interesting too. I have just he thing a pwm controller for the pump so I live in hope it'll never actual need 30A but time will tell

 https://www.tecomotive.com/en/products/tinycwa.html

[DrKai]

For the sake of John's sanity I have resigned a trigger wheel. It couldn't simply be cut out of steel plate as the super damper kit has a flange between pulley and damper. Therefore I had to put a step in the trigger wheel. Cue some CAD again. A 3d printed prototype. And the final version is on order to be laser cut and then machined 

[JohnD]

I fear my sanity is long left me, but I have enought to be most impressed, Kai!

Looks classy as well!

[GT6M]

new t,this thread, an ne body else  has mentioned it, 

but how ye gonna stop  the dredded oil delay,

wid the remote filter set up, which will be worse than OE set up,

 

been there, tried it, took it off.

 

ye sure it,ll have ne oil delay !!!

[DrKai]

I can't avoid the remote filter as the original location would put it directly in line with the bulkhead now.

By delay do you mean lack of pressure on start up? If so I'll fit an accusump if it turns out to be an issue but trying to avoid the expense at present.