Turbo DRLA Jetting

[mikeyvw]

Hey Guys,

I’m getting ready to install a turbo blow thru setup on my 1914. I have Dual DRLA 45’s and wondering where I should start.

Here's a bit about my combo:

Dual DRLA 45’s w/ CB Update Kit
Venturi's ~ 38
Turbo Emulsion Tubes
Modulator Rings ~ 33’s
Heads ~ Mofoco 050’s (42x37.5)
Cam ~ Engle 120
Boost ~ 10-12 lbs.
Compression ~ 8:1
Elevation ~ 300 ft.

Here’s what I need input on...
Needle valve - ??? (I’m thinking 2.50's)
Airs - ??
Mains - ??
Idles - ??
Pump - ??

Thanks for the input!

[GARRICK.CLARK]

I have
33 pump
180 air
55 idle
.2 emulsion tubes
33 mod rings
225 needle
Believe it or not 115 mains. 11.2 AFR at wot with 8 psi using a plx
The reason the 115 main works is that I have T'd off the actuator pipe and fed boost into both float bowls. This richen's up the engine when on boost only. Took me months to suss this out. Clone bug or turbo Baja told me about this but at the time didn't understand how it worked.

[LOUDADDY]

Garrick,
Did you externally tap the bowls or go between the jet stacks?

[GARRICK.CLARK]

Hi loudaddy. What I did was go inbetween the main jet stacks. I enlarged the rectangle hole with a drill. ( did this by hand ). Just large enough for a barbed fitting to be fitted from underneath, so the carb tops do have to come off the dells. Then I used jb weld to surround the barb fitting thus holding it in position and sealing the float bowl at the same time. Then on the turbo hats I drilled a small hole inline with the barbed fitting. This hole is there to allow a piece of nylon tube to be slotted down the hole into the hat and then into the barbed fitting fitted earlier to the carb tops. Tee the 2 nylon tubes together. Tee off the actuator pipe and link the actuator pipe to the nylon tubes going to the carbs. Boost pressure then pressureizes the float bowls and richens up the fuel in boost mode only.
You can see how it works by having the engine running at idle, blow down the Tee'd off nylon tubes going to the carb vents. What happen is when you blow pressure into the tubes. (you can do this with your mouth.) The idling engine will stall cause the pressure being blown into the carb vents makes the auxiliary vents shoot fuel down the throats. This richens up the on boost mid/top end only. Once I did this to my Dell blow through type 4 I had to go from a 140 main down to a 115 main to get the AFR at 11.2 with 8psi..
Hope that makes sense.
My engine would not run right without doing this.
Spent loads of money on fuel testing different jet combos . None would work . This trick works well. Have a look on turbo forum. There's a big write up about this mod.

[DerrickfromNC]

This trick works well. Have a look on turbo forum. There's a big write up about this mod.


G.Clark.....what turbo forum can I find a write on this mod and what search term should I use to find it?

Thanks

[LOUDADDY]

Will the small banjo fittings flow enough fuel for a turbo blow through 2276?
Looks like I could cut the boss off and tap it for an an fitting if need be

[GARRICK.CLARK]

Hi guys. The write up is on the turbo forum . Topic is called vent tube extension

[GARRICK.CLARK]

I changed my banjo eyes but used the original banjo bolt. I drilled out the centre of the banjo bolt and enlarged the holes in the side of the bolt. I also drilled the passageway that supplies fuel to the needle valve. Also if your using the red turbo gaskets I cut a piece out were the carb top vent passage is as the gasket blocks the vent .

[GARRICK.CLARK]

You can get larger banjo eyes in different sizes .mine are for 8 mm I.d petrol.pipe . There are 10mm ones too.

[madmike]

Banjo's are to restrictive swap to A/N fittings, My 48 IDA fittings fit My 40 DOCE ,,not sure on Dells thread sizes but they maybe the same,, If need be I can can my size,LMK,madmike