3.0litre stroker crank set, k-jet fueled?

[TurboDutch]

 

[dl242gt]

Great to see it running! Lots of fun ahead.

 

[TurboDutch]

Thanks mate, still a lot of work to get it on the road. But happy it runs.

Also added some pics of enlarged oil pan.

 

[TurboDutch]

Trying to fit a printed airbox and lpg mixers. The damn huge brake booster was in the way. Managed to source a quite easy conversion from a '00 swift.

Needed to swap the pusher pin from the Volvo booster to the swift booster and needed to bend the fork a bit that attaches to the brake paddle. And made a base plate.

 

[TurboDutch]

So I have been working on it for a while now, get some improvement but not there yet. I changed the cam to a 280 degree one with 12.1mm lift. Just a bit up from a H cam.

I spend quite some time before I understood the carbs where slightly flooding at idle, little leak from the mains.
Found out it is because of the float levels. Set them to 9mm now and just no leaks.

But during cruising it always riches and then leans out, looks like during cruising they are also flooding.
Checked the tilt of the engine and it is tilting backwards quite much, this seems to fuck up the float adjustment, logically.
Should I adjust the floats to the tilt? Or should I try to adjust the tilt?

I changed the cam because I was struggling with low vacuum and issues with running on lpg.

Planning to dyno it coming Wednesday if I manage to resolve the last issues.

Could use some advise about the flooding an the tilt.
Using brass floats.

 

[dl242gt]

Another issue I have experienced with webers and not smooth running from richening and leaning. It was from the needle valve for the floats not opening and closing smoothly. They were jerky meaning they would stick closes and pop open and then stick open and be hard for the float to close. Maybe not your issue but it is something to check with them. I solved the problem with Grose Jets which are ball bearing inlet valves for the floats.

 

[TurboDutch]

Thanks mate, how did you find out?

 

[dl242gt]

Thanks mate, how did you find out?

I just held the top of the carb up and move the float up to closed position. When released the needle on the inlet valve would stay up. Then vibration or a bit of a tap and it would fall. It also didn't slide smoothly from an open to closed position. Just not a good inlet valve. Even a good stock replacement would have worked better. The Grose Jets were cool because they make the whole valve movement based on a couple of ball bearings so it is smooth operation. I see IPD sells them and so do the British car parts venders. Wasn't a performance increase or anything. Just reliable operation.

 

[TurboDutch]

Looks like I got it kinda right now, found that one of the idle jets was blocked

 

[TurboDutch]

Couldn't get it to work properly, dyno't it and saw only 160whp without correction.

Cyl 1 was running pig rich and misfiring.
Ordered new carbs, see what that does.

Then I pulled the head as well to see if it's OK. And to correct some mistakes, after the shop put the valves in I saw there was a lot of blending still to do but I was afraid to damage the seats so I left it.

So now was the chance to make it right.

Will also increase compression more. So will bring it to the shop tommorow again to cut 2mm more of the head.

 

[TurboDutch]

Boys? Can I shave off another 2mm? So totall 4mm? Without issues?

 

[culberro]

What CR and volume in the chambers are you going for?
At over 4mm off the head you’ll probably run into issues with the timing belt being too short.
Use windscreen washer fluid to check chamber depth (or water with soap to cut the surface tension). If you want a chamber volume of 48cc for instance, put 48cc of fluid in the chamber. Them measure from the head gasket surface down to the fluid. That will tell you how much to remove.

Make sure you clean up the washer fluid as it will cause the iron and steel parts to rust up quickly.

 

[TurboDutch]

35cc abt close to 1 tot 12 ratio.
I have 25cc dish, 96.4 bore 101 stroke.
Pistons above the deck 0.2
Using elring gasket

 

[culberro]

35cc abt close to 1 tot 12 ratio.
I have 25cc dish, 96.4 bore 101 stroke.
Pistons above the deck 0.2
Using elring gasket

Dang, those dish pistons are killing the CR.

It looks like you took a lot of material out around the intake valve, I would done less there and more on the exhaust. Use more of a taper as well...
Leave the intake port rough to help in the fuel atomization.

From a quick calc, 42cc would put you around 11:1. My guess is that the carbs were leaving a lot of of power on the table being so rich. I'd shoot for 11:1 (just so you don't have to mill the the head so much) and then get the carbs running correctly. Getting to 12:1 will be 35cc (as you mentioned), but you might (probably will) run out of timing belt tensioner adjustment. Ideally you'd weld up the head to drop the volume.

I've picked up ~8hp on a 540cc single dirt bike by going leaner on the jetting 2 jet sizes and aiming for ~13:1 AFR. It was 12:1 AFR on the dyno with the rich jetting (looked good from plug checking at the track) and just killing the power.

 

[TurboDutch]

Thanks mate, I will ask to mill a bit less. But 11.5 to 1 is really my max so it would be 1.6 more.

Checked out the carbs today as well, I can see past the throttle plates on all barrels. So something is off there. Couldn't find anything more being wrong. But didn't look completely thoroughly yet.

I could weld up the head but, never done such thing. Needs practise first.
Don't like to practise on 531 head. Tbh

Maybe in another project

Edit: and ur totally right I shouldn't have gone with them dish pistons. It was a turbo set with forged piston. So I chose it over normall ones and had the deck shaved 1.3 to get the pistons above deck.

Edit 2: I had 42 cc before, now it's 47. So need to shave some of the head anyways.

 

[TurboDutch]

Yeah buddies!

So made it to the dyno today and after some fiddling found 210 pure wheel horses. So say 250 crank.

With agap cam 14.5mm lift.
Dco/sp 50 carbs with 46mm choke.

It runs very well and it's nice to drive! Feels strong and torqie and it rips!

When I came in it made 178whp.

But it was too rich I knew that! I was trying to get it richer in the higher point. But the dyno guy told me it was because of the race cam it sucks fresh mixture through the carbs so it seems lean in the graph or the afr gauge. But actually it's fine.

 

[culberro]

Just look at that torque

Glad you were able to get it sorted and tuned! The larger carbs were definitely the way to go!

 

[TurboDutch]

Thanks bro! In the future I want to build a perfect head for it. But that might take some time. I already have larger seats and a mind full of ideas.

I am really happy that finally we have some strong results and a strong engine. The cam was downsized a bit on exh lift and duration. For torque. That came out really nice

 

[Stiggy Pop]

this thing rocks!

 

[redblockpowered]

I love it.