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914World.com _ 914World Garage _ DIALING IN MY 48 DELL'S TODAY

Posted by: V6914 Jun 11 2005, 09:56 PM

Had Fun dialing in my 48 Dells, and not finished yet.
It's said Dells flow better than Webers, and they like lots of Jet.

The cam, is a big factor here: 533 Lift 318 Dur

Got the floats set, which were way off.

Next, the idle jets, this is where it starts to get interesting, these carbs are gas hungry, I had to go up to 75 on the idlers, and they may still need a little bit more?

The Mains and Airs: I started with 200 airs and 200 mains,
and so far I've got the mains down to 185's. Ran out of time today, I'll play with them some more tomorrow.

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Posted by: Aaron Cox Jun 12 2005, 02:45 AM

way cool richard.

have you looked into a mallory dizzy? way better advance curve.

AA

Posted by: V6914 Jun 13 2005, 01:25 AM

QUOTE (Aaron Cox @ Jun 12 2005, 12:45 AM)
way cool richard.

have you looked into a mallory dizzy? way better advance curve.

AA

I, am saving up for a MSD, I already have the box(6A) and the wires, and a coil, all thats left is the dist.
I, do need a better curve than the 009, an actually I have an old 030, with a much better curve, but I can't find an electronic ign kit for it.

When in doubt it.

Posted by: Aaron Cox Jun 13 2005, 09:28 AM

i had an 050 with a pertronix in it. worked OK. mallory dizzy and hyfire CDI

BTW - people say that the unilite is easier to tune than the MSD dizzy. and yep, you can hookup the unilite to the MSD 6 box no problem.

AA

Posted by: yeahmag Jun 13 2005, 10:51 AM

That is a lot of duration on that cam. For what it's worth almost all the 48 Dell owners (I have the Tri-Jets) run something like:

40mm Venturi
70idle
180 main
200 Air
.2 E-Tube

With my high CR, close deck height motor I was able to go down to 170 on the mains!

How many turns are your idle screws out? 75 is a BIG idle jet. Not to state the obvious, but be sure to tune the idle circuit when the car is fully warmed up. Otherwise you will always be too rich when warm.

-Aaron

Posted by: V6914 Jun 13 2005, 01:11 PM

QUOTE (yeahmag @ Jun 13 2005, 08:51 AM)
That is a lot of duration on that cam. For what it's worth almost all the 48 Dell owners (I have the Tri-Jets) run something like:

40mm Venturi
70idle
180 main
200 Air
.2 E-Tube

With my high CR, close deck height motor I was able to go down to 170 on the mains!

How many turns are your idle screws out? 75 is a BIG idle jet. Not to state the obvious, but be sure to tune the idle circuit when the car is fully warmed up. Otherwise you will always be too rich when warm.

-Aaron

How many turns are your idle screws out?

There out so far, I might have to put some teflon tape on the threads so they don't fall out . 75 idlers where the biggest I could find on short notice.

I, droped my venturi's down to 38mm, trying to see if that help.

I, bought these used, but just been rebuilt?, on the net, missing gaskets, the bolts were to long on the top plate, was worried the PO cracked the housing, with the longer bolts, the squirters for the accelrator pumps, were missing the little o rings, so it was also squirting between the housing and the tubes, it's been fun , you take chances when you buy off the net.

I, droped my CR from 12 to 1 to 10 to 1, an ran out of time, was going to swap out cams, one with more lift but less dur, had a deadline, had to return the car I borrowed, while mine was down, did it with a day to spare.

Aaron, thanks for the info, it helps to have a jet reference
to work from, and it shows me I am in the ballpark.

My motor is a 2632 105.7 x 75.

Posted by: Mueller Jun 13 2005, 01:41 PM

QUOTE
I, am saving up for a MSD, I already have the box(6A) and the wires, and a coil, all thats left is the dist.

Wanna make a trade?

I have a barely used* billet Mallory Unilite ($265) with a Mallory HyFire VI-A ($120), new SuperMag 8.5mm wires ($40), new Promaster Coil ($70) and a Mallory spike protector ($34) that I might be selling......

*about 45 miles

I am running an aftermarket Fuel Injection and they support MSD products for use with thier stuff, but not Mallory and I'm having some strange problems and might be going to all MSD instead......

Posted by: yeahmag Jun 13 2005, 10:01 PM

Are you running race fuel by chance? It's different in viscosity then standard pump fuel and may account for your large jets. Other than that I'm surprised by the jet size that thing wants to run. Might want to sanity check your float level adjustment...

Good luck!

-Aaron

Posted by: V6914 Jun 13 2005, 11:04 PM

QUOTE (Mueller @ Jun 13 2005, 11:41 AM)

QUOTE
I, am saving up for a MSD, I already have the box(6A) and the wires, and a coil, all thats left is the dist.

Wanna make a trade?

I have a barely used* billet Mallory Unilite ($265) with a Mallory HyFire VI-A ($120), new SuperMag 8.5mm wires ($40), new Promaster Coil ($70) and a Mallory spike protector ($34) that I might be selling......

*about 45 miles

I am running an aftermarket Fuel Injection and they support MSD products for use with thier stuff, but not Mallory and I'm having some strange problems and might be going to all MSD instead......

Thanks for the offer, but all my stuff is used, the MSD box was made for GM Nascar teams, as was the 40,000 volt coil, and the wires are heat shielded Delphi- Packard Electric Motorsports, used wires.

And for a distributor, I just found out today, that Pertronix now makes a billet distributor, with adjustable curves, and same type cap as the MSD, for around $180, I may try that.

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Posted by: Mueller Jun 13 2005, 11:18 PM

QUOTE
thanks for the offer, but all my stuff is used, the MSD box was made for GM Nascar teams, as was the 40,000 volt coil, and the wires are heat shielded Delphi- Packard Electric Motorsports, used wires

that's cool, I ended up ordering a new MSD with the required internal resistor upgrade.......I'll end up keeping everything except for the HyFire.....hope i don't have to sit on it too long before it sells

Posted by: V6914 Jun 13 2005, 11:26 PM

QUOTE (yeahmag @ Jun 13 2005, 08:01 PM)
Are you running race fuel by chance? It's different in viscosity then standard pump fuel and may account for your large jets. Other than that I'm surprised by the jet size that thing wants to run. Might want to sanity check your float level adjustment...

Good luck!

-Aaron

The float levels, was the very first thing I set, and I was running race gas before, before, I droped the compression, I'd add over a gallon of race gas, every time I filled the tank, I can't afford to do that now, with the gas prices, that was 1 of the reasons I droped the compression.

There are a couple of issues, exhaust and ignition, I won't be able to properly dial in the carbs, untill I take care of those 2.

I'll, keep this post updated, as I figure out all this stuff.

Posted by: Jake Raby Jun 14 2005, 12:21 AM

More CR will typically attain BETTER MPG through lower BSFC from the added efficiency of the combustion...

I'll bet that engine would make 15-20 HP MORE with 45mm carbs- I have NEVER seen a 48mm carb make more power than a 44 or 45 on any size TIV with stock casting heads, no matter how modified...

Velocity is the answer- Not volume.

I have picked up 25 HP from swapping from a 48mm carb to a 45 on many occasions.

Bigger is not better- Think smart, look at the head flow numbers and you'll see that the heads stop flowing at 65% of the overall carb flow from those monsters and due to the lack of velocity atomization is effected...

Just my 5% worth, now I'm outta here for 3 more weeks so i can get something done!