spoolin

i have a couple questions for the dell gurus: i have a stumbling problem and need some guidance and input.

first i would like to say that i already have the gruntled pages printed off and have for almost a year now.

in the morning, cold ones, it barely wants to run...farting through the carb... and has a problem when i give it gas, it drops and then goes. sometimes, i can give it gas and it seems like it bogs down and then one the mains come online, it runs great. the porblem is, i don't have the jets that everyone has on their idle circuit. i have a .4 holder and and a 65 idle ( i think, it's been a while since i've had it out)
anyways, i've read the sheets from brad and wes and am getting close to insanity. can some one pull their jets and give me a closest SAE measurement as i guess i will try to drill the holder out.

i've tried CB performance and she said that the jet holder that i need (the one in the pages from brad.... i think the .8) is not available. if someone knows different or has a set i could buy, please help me out. the 80 jet i could get through them.

jutny

i'm looking for dell'orto information too

basically, i need information on what is what... a diagram of what everything is... and all sorts of nifty simple **** like that. I also need a main bleeder ( i think that's what it is... the one at the bottom of the carb) because one of mine is bent... it still seems to work though. There is also a needle valve missing, one of the things right above the bleeder.

also, the choke on it is choked in the position close to the car? and unchoked in the forward position. How does this nifty choke work anyhow?

also, a vac port for my advance.... where?

DriveFast7

iTrader: (1)

hi spoolin, brad here. my info is on gruntled.com

the idle holder I spec'd on gruntled.com is the one you want. call jorge @ European Motorworks 1.800.722.8678 he should have it or can get it for you.

I need to know more about your motor and exhaust modifications, if any, in order to help out. For starters you should have at least 75 idle fuel jet.

Dellorto, Mikuni, and Weber jets are in millimeters where a jet size 100 is 1.00 mm. so a 75 jet is .75 mm The just off throttle bog you describe is a lean projession circuit, caused by wrong idle jets.

jutny, dellorto diagram is here:
http://www.gruntled.com/Dellorto/Diagram.html

the choked position is the position where you gotta push the choke into. i can't remember offhand but if it snaps back, the snap back position is unchoked. it's not truly a traditional choke with a butterfly restricting airflow. it is a 'fuel enrichment circuit' which allows air to bleed out the black plastic plate on top of the carb, thereby enrichening fuel flowing thru carb.

=bp-

jutny

so, when you're standing at the passenger side of the car looking at the carb (inlets away from you)... the choke when its in normal running mode should be in the forward (front of car) position?

spoolin

i have a 4 port 13B streetport, racing beat sp exh system, msd blaster 2's and holley red. i also upgraded my fuel line to a 3/8. i'll check w/ jorge tomorrow.
also, this may be weird as the float bowl meaurement, but can you give me a measurement from the bottom of the bowl to fuel level height. i got a rebuild kit from cb earlier this year and the needle and seat were different from the ones i pulled out. i saved them but was wondering if you could just give me the fuel level height. i guess you could measure it from the top once you take the lid off, ya know what i mean?

DriveFast7

iTrader: (1)

I just popped the hood on the REPU and the choke on it's dellorto is on when the little lever is pushed towards front of car. Not choked when facing the rear of the car.

Although I don't have an air/fuel meter on the REPU, it does have the early style larger intake ports, which are close to a streetport. It's a factory heavy rotor 4 port 13B. It's dellorto jetting is 205 fuel and 215 air. With the Racing Beat drilled/modified .8 emulsion tubes. And 41 mm chokes! Sorta odd jetting when compared to the jetting on my 12a streetport but it works well. It has 1.75" dual pipes and four foot long glasspacks into a cheapo muffler. It does have 75 idle fuel jets and it does stumble on the progression circuit, I mean to put 80s in there when I got the time.

Your engine and exhaust system isn't too far off from that so you can try that jetting but I can't guarantee it. Jets are cheap though. I've bought DOZENS from Jorge! Most guys with big port 13b's, 41mm chokes and good exhaust just put 240 fuel and 230 air jets in there.

From Will Claypoole's excerpt on www.gruntled.com:
"Racing Beat recommends float levels of 15mm from the gasket in the closed position and 28mm in the wide-open position. It’s important to realize that the 15mm measurement is taken BEFORE the needle spring is compressed. These measurements provide a good compromise between the right hand turn stumbling and flooding the carb by over filling the float bowls. After a lot of experimenting and testing, I've found that a 14mm float height provides improved response and less stumbling than the RB recommended 15mm height and zero flooding. True this setting will cause the carb to run slightly richer (due to the fact that the emulsion tube is more submerged in fuel) but I think that this richer mixture accounts for the smoother operation and near zero stumbling while cornering to the right. Going much beyond 14mm results in even smoother operation, but the instances of flooding after hard cornering or sudden braking also increase. I'll be experimenting with this for a while, and I'll make sure to report back to Dave with the results."

You really need the 3.00 needle and seat that came with the RB dellorto kit. Otherwise it won't flow enough fuel and run lean.

Best of luck!

Brad

Rotor13B

Yeah, CB perforance no longer sells the 300 needle and seat, you get the... wait a minute..., ok, it's the 225 needle and seat. I've heard of people boring this set, but don't know how well this works. I ended up just using the same needle and seat because it looked to be in good shape even under good magnification and it had no grooves or anything around the needle. just a thought.

spoolin

well ****. i thought i had the original needle and seat from the rebuild and i can't find it. i hope it is just misplaced and it resurfaces....but i do remember that when i replaced it, i saw a difference in the oriface and enlarged it a bit to help flow. right now, i'm running 240 fuel and 220 air. it seems ok when doing wot but just getting over the blup when you get on it. the thing is, after it's warmed up, it doesn't do it. just in the morning/afternoon when first after a long sit and gets cold. i swore to myself i would get a longer choke cable this past summer so i wouldn't have to deal with that issue in the winter and.......procrastination is the work of the debil .
oh yeah, i was mistaken. it's been a while since i looked at the pages and i realized his name was will, not wes or whatever i said. sorry
i'm ordering from jorge now,
thanks,
roy

spoolin

ok, i just double checked everything. i have a .8 holder w/ a 75 jet. i have seen a .4 and noticed that the hole in top of the holder was larger than the one i had. at the time, i had two of these carbs and was working a deal out with a local shop owner that i give him one and he gives me the parts i needed to go from 12A to 13B in my car. so i picked the carb and jets to the best of my knowledge- none. i always new that these cars like it rich so i thought the .8 holder would be better than the .4. the jets were the same out of bothe carbs. as well as the 80 pump jets. one had 230a/230f while one had 230/a and 210/f i had some spare jets from years ago with my old SE and now i have the previously mentioned 240/f and 220/a.

now what oh great one (brad)? jorge wasn't there and i was going to double check the pages and parts on car. i saw something about your little note about the car seems to like the 90's better in the pump jet. any new info? i was planning on getting the side intake from atkins and wanted to know a little more about the setup for that combination. i want to get the better peak power and according to you the lake cities inatke is the way to go. i don't know how that will affect a big block since the B's have a little more torque than the 12A's do b/ as i recall your statement about less bottom end.

spoolin

here's a pic of the holder in the carb so you know what i mean about the smaller hole. i figured that it would be better than the other (.4) with the same idle jet as it would be richer. maybe i'm missing something here. oh well, i will place the order for the .4 and 80 later today.

DriveFast7

iTrader: (1)

i'm not sure about the 90 accelerator pump jet yet. it seemed to like it on the track but not sure how it'll behave on a street only car. stick with the 80.

if you go with a atkins/lake cities manifold you'll have to rejet. that manifold flows better and has different characteristics. look at my jetting differences between RB and LakeCities manifold on www.gruntled.com and you'll see. you'll need to go a little richer for a 13b streetport. also the 6" tall RB air filter is too tall and will hit the frame rail and inner fender. I ended up with a 3.25" tall air filter that was just as wide and high as the RB one. Still could fit the RB 50mm velocity stacks and have 1.25" clearance inside the filter. Jorge ordered me that filter, took like 3 weeks! Plus it needs a 20" longer throttle cable I had one custom made. Choke cable needs to be longer too. It's some $ and time to switch to lake cities manifold but it really is worth it.

with the Lakecities manifold and 39mm chokes the motor will rev up fast and be a screamer, but with less low end torque. for the street i switched to 37mm chokes to get bottom end back, and still had GREAT top end.

i know what you mean about the idle holder hole.

-brad-

Rotor13B

Doesn't lake cities have a wrap around intake also? I seem to remember someone saying they had one. A one peice uper intake.

diabolical1

iTrader: (3)

I'm sorta curious about this myself ...

DriveFast7

iTrader: (1)

Well like I've said before lake cities/atkins rotary side (above header) intake manifold makes a lot more peak hp, has MUCH more throttle response. It does make less bottom end, but when I went from 39 to 37 mm chokes in the dellorto with that manifold, it STILL made more peak hp and much more throttle response, and the torqe was about the same with those 37 chokes. WELL worth it. B motor makes more torque than A like you said. GO FOR IT.

Crit

iTrader: (6)

Hey guys. I hate to bring back a long-dead thread, but I'm trying to sort out my DHLA. The 4 main jets that you can adjust with the engine running are 230 and 75 (I don't know what's what), and the larger 2-piece jet near the progression slots is an 80. I'm ordering a rebuild kit but have no idea what jets I need. I'll order some if I need 'em. I just need some advice. I have a POS Holley that's standing in, so I can drop the Dell on once it's sorted out. What jets would be appropriate for my setup? If I want a range, so I can swap between them, what would a good "collection" of jets be? This is all for a SP 4-port 13B. Also, any idea what jets would cost from Jorge?

DriveFast7

iTrader: (1)

MY REPU has a streetported 4-port 13b witha hipo exhaust and is running very good right now.

235 main fuel
220 main air

75 idle fuel jet
.8 idle fuel jet holder

go to gruntled.com for more info
go to amazon.com and search on "dellorto" buy the book "how to build and powertune your weber dcoe and dellorto dhla"

a few bucks per jet.

spoolin

mine was running good. now its sitting in my backyard waiting for me to pull the engine and rebuild it. i need to wash and wax it to keep my paint in good condition.

but i'm building my bridgeport for the other car at the same time!!

Crit

iTrader: (6)

www.gruntled.com isn't up. What was I to check out there? Also, my carb's pretty dirty and I'd like to clean it up. Spotless, but not polished. What do you guys use?

Crit

iTrader: (6)

By the way, can someone give me a crash course on the way jets break down? I called european and frustrated someone pretty badly. I can only make out 2 sets of numbers along the 2.5 inches of brass that I'm told is the air jet. He said that they're 3 separate sections and that I need 3 numbers, but can't find it all. Can someone explain it to me?

DriveFast7

iTrader: (1)

Use Castrol Super Clean, a tooth brush and latex gloves. Don't let the Castrol sit on there for more than a minute before washing off, as it discolors aluminum. But works WONDERS when cleaning.

Otherwise Brake Cleaner and Simple Green are great; but flush the carb well after Simple Green since it was found to corrode aluminum over time unless flushed off.