type 4 motor

[Bruce.m]

The Spring stops fuel returning to the tank by closing the opening using the diaphragm. As the fuel pressure rises the spring compresses and the diaphragm lifts letting some of the fuel to return to the tank. The vac port when connected to boosted air pressure, also pressed down on the diaphragm so the fuel pressure will have to increase further before the diaphragm will lift and allow some to bypass to the tank.

[GARRICK.CLARK]

arrr right . I see how it works now, thanks Bruce .
Well seeing as I've been trying to fix this on and off for over a year I've decided to go DRAW THROUGH.
Gotta be easier with only 1 carb. A single 2" S.U HS8.

TBC

[GARRICK.CLARK]

Hi Guys.
I done the conversion now, fitting an S.U HS8 2" CARB before the turbo.
Not driven it yet but its looking and sounding good.
1 thing I'm trying to get around is that there is lag on the carb piston. The piston lifts under depression and raises the carb needle to richen up the engine. The AFR gauge numbers are good.

[GARRICK.CLARK]

Guys. I'm trying to fix an over run issue when turning the ignition off.
Here's a list of potential problem areas.
1. Wrong heat range of plugs. I think I should be using NGK B8ES not projected plugs.
2. Wrong grade of fuel.
3. The fact that my GT turbo I'm using needs a carbon seal fitted. Possibly sucking some oil into the inlet pipe lowering the fuel grade.
4. Oil cooler with fan which is bolted over the top of the gear box being in the wrong place to efficiently cool the engine. Engine might be relying more on the cooler in the fan shroud.
5. I have to use extended deck lid stand offs to be able to fit the engine over the turbo .
6. No rear valence, turbo fitted in the space were valence would be.
7. Does the propped open engine lid scoop air into engine bay area or is it a dead air area.

[madmike]

Or B9es you want the coldest plug u can run without fouling
My aux oil cooler is the same as yours and no DogHouse cooler at all temps are ok
I don't run a deck lid

[GARRICK.CLARK]

Hey thanks Mike, If I could get rid of the dog house cooler that would get rid of some piping too. I don't think the coppers would be happy with no engine lid fitted. i'll ask if its legal. But to be fair it would be like a baja bug rear end (ish) wouldn't it or a buggy, they seam to get away with it.
Have put some ducting up to your oil cooler.

[Piledriver]

Deck lid standoffs work well for cooling, but a rain tray or at least a rain hat over the intake is needed.

[madmike]

I have no ducking to the cooler over the trans,
I did install another finned tube cooler over the motor under the rear window (pic in the thesamba gallery) and I also route my oil threw the intake(sidedraft) which helps , my temps according to the autometer gauge
210* instead of 240* climes to 230* when fooling around and back down cruising

[andy198712]

what happens when you pull the ALT light wire behind the speedo once the key is turned off and its running?

[GARRICK.CLARK]

Its not that Andy

[andy198712]

Oh

[Piledriver]

You still need something to keep the hot side/cold side separated, not suck hot stale air or hot air off the turbo/exhaust into the cooling fan.
(the same concept is essential for any cooling fan setup, oil cooler/ac condensor or radiator setup same, if it can recirculate, it will)

Is there any way you can set up a "pregnant" valence, sort of like the late FI ones, just to give the rear engine tin and seal somewhere to seal? even if its just where the seal lives and open below.

[GARRICK.CLARK]

Hi Pile . In front of the bottom pulley is the header merge , turbo and filter set up. I might be able to put a shield in between the pulley and turbo, to sort of wrap the hot side of the turbo .
I think I need to move the ext oil cooler , I don't think there's much air flow under the rear parcel tray which is were I have it position now.
I have now put some B8ES plugs which has stopped it running on when the ignition is switched off.
Did a plug check today after a good run. I was surprised to see that the outer ring of the plug has no carbon at all on it, only the earth and porcelain is dark charcoal colour. I gapped the plugs to 20 thou also.
The bug is pretty quick now. Almost OMG.
I cant put foot to the board without some low decibel back firing .

[Clonebug]

I would try a gap at .028

[GARRICK.CLARK]

Hi Pile . In front of the bottom pulley is the header merge , turbo and filter set up. I might be able to put a shield in between the pulley and turbo, to isolate the hot side of the turbo from the engine.

I have now put some B8ES plugs which has stopped it running on when the ignition is switched off.
Did a plug check today after a good run. I was surprised to see that the outer ring of the plug has no carbon at all on it, only the earth and porcelain is dark charcoal colour. I gapped the plugs to 20 thou also.
The bug is pretty quick now. Almost OMG.
But I still cant put foot to the board without some low decibel back firing .

.
When I had the boost retard canister fitted the back firing under boost were very loud, so I removed it and fitted the standard advance canister. No huge back fires.
With the standard advance fitted and plumbed in I had pinging at off boost running with up hill driving.
SO. I removed the vac advance and only run mechanical advance.
NO pinging , only low decibel multi back firing at boost over 10 psi.
Should the advance come in early or late.

What should I try next.