Posted By: viperblue72
holley jet size 35? - 11/11/14 10:24 PM
Rebuilding my volley 1920 one barrel and I don't understand why my jet has the numbers 35 on the front. That can't be the size can it?
holley jet size 35?
Posted By: Cab_Burge
Re: holley jet size 35? - 11/11/14 10:39 PM
Holley marks there jets with a flow number, not a inner diameter 
Posted By: viperblue72
Re: holley jet size 35? - 11/11/14 10:43 PM
Quote:
Holley marks there jets with a flow number, not a inner diameter
I am still confused with this number. My trick has been getting terrible mileage. I believe the carb should have either a #56 or size 56 can't remember. This is a 1968 carburetor so I just wonder if they numbered the jets differently back then? It can't be a size 35 can it?
Posted By: Supercuda
Re: holley jet size 35? - 11/11/14 10:46 PM
Maybe it's a mis stamped 53?
Had a similar issue with my 72 swinger's 225. turned out the reman carb had a jet 6 numbers bigger than stock. Bought the right jet and things were all good. Mine was supposed to be a #50 IIRC.
Had a similar issue with my 72 swinger's 225. turned out the reman carb had a jet 6 numbers bigger than stock. Bought the right jet and things were all good. Mine was supposed to be a #50 IIRC.
Posted By: viperblue72
Re: holley jet size 35? - 11/11/14 11:11 PM
Quote:
Maybe it's a mis stamped 53?
Had a similar issue with my 72 swinger's 225. turned out the reman carb had a jet 6 numbers bigger than stock. Bought the right jet and things were all good. Mine was supposed to be a #50 IIRC.
That was my thoughts too. Maybe stamped backwards.
Posted By: JimG
Re: holley jet size 35? - 11/11/14 11:56 PM
There is an approximate relationship between the stamped numbers and the diameter of the orifice. As previously mentioned, the number is stamped after the jets are flow tested, so diameter will get you in the ballpark.
If you have a set of numbered drill bits, you can measure the diameter using the go/no go method, figure out the diameter of the largest drill bit that still fits inside, then Google for the chart that tells you the approximate diameter of each jet size.
That, at least, will tell you if it's stamped wonky or not.
If you have a set of numbered drill bits, you can measure the diameter using the go/no go method, figure out the diameter of the largest drill bit that still fits inside, then Google for the chart that tells you the approximate diameter of each jet size.
That, at least, will tell you if it's stamped wonky or not.
Posted By: 62maxwgn
Re: holley jet size 35? - 11/12/14 12:18 AM
The # 53 jet is actual drill size .052.
Posted By: B5 Bee
Re: holley jet size 35? - 11/12/14 12:25 AM
If there is such a thing as a Holley #35 jet, that's not it...hole is too big.
I'll be tearing into the 1920 Holley off my '68 V200 this weekend, the accelerator pump crapped out. I'll report back what jet is in it, btw it's the original carb, not a reman with a replaced jet.
I'll be tearing into the 1920 Holley off my '68 V200 this weekend, the accelerator pump crapped out. I'll report back what jet is in it, btw it's the original carb, not a reman with a replaced jet.
Posted By: RapidRobert
Re: holley jet size 35? - 11/12/14 12:27 AM
What's going on with the mileage? what eng yr make model gears timing choke recent work, everything. Recent issue or always there. What MPG
Posted By: B5 Bee
Re: holley jet size 35? - 11/12/14 12:30 AM
That "#35" jet looks closer to a #85.
And it looks more like a Carter jet, Holley stamps jet #s on the side, not the face.
And it looks more like a Carter jet, Holley stamps jet #s on the side, not the face.
Posted By: 62maxwgn
Re: holley jet size 35? - 11/12/14 01:02 AM
The majority of the 1920 Holley's use a #53 jet.In this manual the # 35 is a reference number,not the jet size.
Posted By: viperblue72
Re: holley jet size 35? - 11/12/14 06:59 PM
Quote:
What's going on with the mileage? what eng yr make model gears timing choke recent work, everything. Recent issue or always there. What MPG
The truck is a '81 2wd slant 6 auto. It has the lean burn on it. The vacuum pot wasn't working. I replaced the distributor yesterday for one with vacuum advance that's actually working. I also rebuilt the carburetor, but the carb seemed ok. The gears seem to be likely 3.55s. I was getting 11 mpg.
Hopefully these changes will help. I have an msd 6al that's going on it as well. I may just order a jet, so that I know what's in it. I don't have drill bits that small.
Posted By: RapidRobert
Re: holley jet size 35? - 11/12/14 10:06 PM
OK so you have a 68 stand alone (non lean burn) carb & a good vac adv dist. other than the std tune up issues: compression check/no vac leaks/ballpark timing/good plugs/wires etc as you said you might order some bigger jets & good point the guy mentioned that Holly jets are stamped on the side (at least the ones in my white plastic holley jet box are). Oreillys is pretty good about ordering run of the mill speed parts & could probably get some jets in for you. Not sure which company sells them individually but I've seen em. You might get a 40-50-60 & do some experimenting. Holler how things go
Posted By: viperblue72
Re: holley jet size 35? - 11/12/14 10:26 PM
Robert,
Yes, I replaced the carter that was on it with this simple little 1920. Then added a nos vacuum advance distributor.
The carter ran terribly but got 14 mpg. When I put the holley on, it ran great and had a lot more power. But much worse mpg. This is when I started going over everything. The truck is running excellent now, but mpg is yet to be determined. If this doesn't help as much as I would like, I still plan to swap an 8 3/4 with taller gears. Thanks for all the input.
And of course change the jet.
Yes, I replaced the carter that was on it with this simple little 1920. Then added a nos vacuum advance distributor.
The carter ran terribly but got 14 mpg. When I put the holley on, it ran great and had a lot more power. But much worse mpg. This is when I started going over everything. The truck is running excellent now, but mpg is yet to be determined. If this doesn't help as much as I would like, I still plan to swap an 8 3/4 with taller gears. Thanks for all the input.
And of course change the jet.
Posted By: RapidRobert
Re: holley jet size 35? - 11/13/14 02:37 AM
To clarify: it got 14mpg with the carter and the NOS dist installed then ONLY the carb was switched to the holley (same dist) & the mileage went downhill?. Same ported or non ported for the can? I'm assuming there is a good reason why you dont put the carter back on there. those 1920's are so simple/fun to work with. I would wanna get to the bottom of it just for the satisfaction. I'd get some jets and recheck the float (level/saturation)/no base gasket or vac line leak. Holler how it turns out. not sure the 35 is right & I have one & I'll see if I can pull the bowl & see what jet is in it (not sure what year it is) but what I have outa tell us something. EDIT reread & saw the "terribly". describe that
Posted By: viperblue72
Re: holley jet size 35? - 11/13/14 03:11 AM
Quote:
To clarify: it got 14mpg with the carter and the NOS dist installed then ONLY the carb was switched to the holley (same dist) & the mileage went downhill?. Same ported or non ported for the can? I'm assuming there is a good reason why you dont put the carter back on there. those 1920's are so simple/fun to work with. I would wanna get to the bottom of it just for the satisfaction. I'd get some jets and recheck the float (level/saturation)/no base gasket or vac line leak. Holler how it turns out. not sure the 35 is right & I have one & I'll see if I can pull the bowl & see what jet is in it (not sure what year it is) but what I have outa tell us something. EDIT reread & saw the "terribly". describe that
Robert that's correct, only changed the carburetor to begin with. The Carter was remanned and was very wore out. I also prefer the simplicity of a holley. I ordered a #53 that I will compare and put in. Not sure what you mean by ported or non ported can. I will also report back if the distributor change fixes it.
Posted By: RapidRobert
Re: holley jet size 35? - 11/13/14 03:21 AM
"ported/non ported" was the vac can plumbed to the ported (likely) base nipple on both carbs (no vac to the can at idle). Stay in touch with this. EDIT Did it take alot more throttle with the holley than it did with the carter to get the same amount of accelleration?
Posted By: viperblue72
Re: holley jet size 35? - 11/13/14 03:37 AM
Robert,
the cannisters were not plumbed anymore when I got the truck. Far as acceleration, I couldn't put my foot very far into it with the carter. It had too many vacuum leaks, and would just fall on it's face. Matter of fact I could only drive it about 51 mph. lol.
the cannisters were not plumbed anymore when I got the truck. Far as acceleration, I couldn't put my foot very far into it with the carter. It had too many vacuum leaks, and would just fall on it's face. Matter of fact I could only drive it about 51 mph. lol.
Posted By: TJP
Re: holley jet size 35? - 11/13/14 03:58 AM
Quote:
And it looks more like a Carter jet, Holley stamps jet #s on the side, not the face.
I'll disagree. I have a buttload of holley jets from the 70's & 80's, All stamped on the face
Posted By: viperblue72
Re: holley jet size 35? - 11/18/14 06:16 AM
I can't update mpg yet. But with these changes my top speed went from 78mph to 85mph. I'll update mpg soon.
I also installed a #56 jet. It appears smaller than what was in it.
I also installed a #56 jet. It appears smaller than what was in it.
Posted By: Supercuda
Re: holley jet size 35? - 11/18/14 02:36 PM
Pretty sure a #53 or a #56 jet is too fat. My 72 225 ran a #50 stock.
Posted By: dogdays
Re: holley jet size 35? - 11/18/14 06:04 PM
Just from looking at the picture I can tell you your old jet was at least a 72.
You may be able to go smaller one or two jet sizes from stock, maybe more depending on your altitude. I'd start reducing jet size until you get lean surging at cruise, then go up one number. Holley says you have to make a two number switch to have a noticeable change, but on such a small carb I'd go one step increments.
I have bought jets on the 'bay but I have found a local place that'll sell me a pair of jets for $4.00. Some are new, some used...but unless some donkey messed with the holes, they work.
Another area where one can make the engine work better is ignition advance curve. Unless you have a problem with detonation, bringing it in faster will add some snap to the engine's performance.
R.
You may be able to go smaller one or two jet sizes from stock, maybe more depending on your altitude. I'd start reducing jet size until you get lean surging at cruise, then go up one number. Holley says you have to make a two number switch to have a noticeable change, but on such a small carb I'd go one step increments.
I have bought jets on the 'bay but I have found a local place that'll sell me a pair of jets for $4.00. Some are new, some used...but unless some donkey messed with the holes, they work.
Another area where one can make the engine work better is ignition advance curve. Unless you have a problem with detonation, bringing it in faster will add some snap to the engine's performance.
R.
Posted By: 62maxwgn
Re: holley jet size 35? - 11/18/14 06:56 PM
Quote:
I can't update mpg yet. But with these changes my top speed went from 78mph to 85mph. I'll update mpg soon.
I also installed a #56 jet. It appears smaller than what was in it.
Out of curiosity what what is the actual carb number ?
Posted By: viperblue72
Re: holley jet size 35? - 11/18/14 08:30 PM
Quote:Quote:
I can't update mpg yet. But with these changes my top speed went from 78mph to 85mph. I'll update mpg soon.
I also installed a #56 jet. It appears smaller than what was in it.
Out of curiosity what what is the actual carb number ?
I don't have the carb number now, but I did look the numbers up and it was out of a '68 dodge pickup.
I have not been able to find anywhere stock jet sizes were listed. I got the #56 from a guy on the net, so it's not necessarily right.
Posted By: viperblue72
Re: holley jet size 35? - 11/18/14 08:32 PM
Quote:
Just from looking at the picture I can tell you your old jet was at least a 72.
You may be able to go smaller one or two jet sizes from stock, maybe more depending on your altitude. I'd start reducing jet size until you get lean surging at cruise, then go up one number. Holley says you have to make a two number switch to have a noticeable change, but on such a small carb I'd go one step increments.
I have bought jets on the 'bay but I have found a local place that'll sell me a pair of jets for $4.00. Some are new, some used...but unless some donkey messed with the holes, they work.
Another area where one can make the engine work better is ignition advance curve. Unless you have a problem with detonation, bringing it in faster will add some snap to the engine's performance.
R.
With the new distributor, I did have to back the timing off just a bit due to detonation. Now that the vacuum advance is working.
Posted By: viperblue72
Re: holley jet size 35? - 11/18/14 08:35 PM
Any info on what jet sizes to use would be appreciated. This #56 is a large improvement, but one person says #56, another #53, another #50, etc.
I would love to tune this thing to run just a tad lean would be optimal for best performance, mpg, and longevity.
I would love to tune this thing to run just a tad lean would be optimal for best performance, mpg, and longevity.
Posted By: Supercuda
Re: holley jet size 35? - 11/18/14 09:01 PM
My suggested #50 jet was based on the 72 Dodge FSM's listing for a 72 Swinger with a 225, which is what I had. That carb had a #56 in it and got horrible mileage.
Posted By: viperblue72
Re: holley jet size 35? - 11/18/14 09:13 PM
Quote:
My suggested #50 jet was based on the 72 Dodge FSM's listing for a 72 Swinger with a 225, which is what I had. That carb had a #56 in it and got horrible mileage.
Thank you for the info! I appreciate your info And I will try and work my way down once I confirm it's rich.
Posted By: 62maxwgn
Re: holley jet size 35? - 11/18/14 10:56 PM
After going through the master parts manual the 53 jet is listed for eight 225 truck applications in 1968 except for one and that is a 56.
Posted By: viperblue72
Re: holley jet size 35? - 11/18/14 11:26 PM
Bill,
Thank you for looking that up for me. I will probably downsize my jetting to stock, and go down a size or two from there if possible.
Fwiw it was listed as a '68 automatic pickup.
Is there anywhere I can find this kind of information on the internet?
Thank you for looking that up for me. I will probably downsize my jetting to stock, and go down a size or two from there if possible.
Fwiw it was listed as a '68 automatic pickup.
Is there anywhere I can find this kind of information on the internet?
Posted By: Supercuda
Re: holley jet size 35? - 11/18/14 11:29 PM
There you go, better data.
Posted By: viperblue72
Re: holley jet size 35? - 11/19/14 12:11 AM
Steve,
I know these didn't all come with the same size jet. I'm sure you gave me correct information for 72.
I know there were very slight variances of the volley 1920. But I have no idea why there are so much variance in jet size.
I am comfortable putting the original jet size back in for some reason. I know all slant sixes were almost unchanged through the years for the 225 other then slight here and there. My 81 never came with this carburetor but I love the simplicity and how it is running. I hope I didn't sound as if I was brushing anyone's advice. I will be glad to use a 50 jet if my engine is happy. Being some of you are curious about my mileage improvement as I am too. I will fill her up tonight and calculate it and report back. Check my plugs and likely order some more jets.
Sorry for the long winded post.
I know these didn't all come with the same size jet. I'm sure you gave me correct information for 72.
I know there were very slight variances of the volley 1920. But I have no idea why there are so much variance in jet size.
I am comfortable putting the original jet size back in for some reason. I know all slant sixes were almost unchanged through the years for the 225 other then slight here and there. My 81 never came with this carburetor but I love the simplicity and how it is running. I hope I didn't sound as if I was brushing anyone's advice. I will be glad to use a 50 jet if my engine is happy. Being some of you are curious about my mileage improvement as I am too. I will fill her up tonight and calculate it and report back. Check my plugs and likely order some more jets.
Sorry for the long winded post.
Posted By: Supercuda
Re: holley jet size 35? - 11/19/14 12:50 AM
Hey, no sweat, I didn't know the specs for a 68 truck and I couldn't find anything on the net, so I gave you the specs I had as a starting point. As long as it works out in the end that's all that matters. My Swinger was a CA emissions car so who knows how that might affect it.
Posted By: RapidRobert
Re: holley jet size 35? - 11/19/14 02:31 AM
Viper that ain't a long winded post! I went & checked my Holley jet box & was surprised that they start at 64 from the numbers in this thread that are way lower
Posted By: 62maxwgn
Re: holley jet size 35? - 11/19/14 03:14 AM
Quote:
Viper that ain't a long winded post! I went & checked my Holley jet box & was surprised that they start at 64 from the numbers in this thread that are way lower
That's because that box is the performance jetting,not applicable to one and two barrel carbs.You'll find those jets all have the number stamped on the side.
Posted By: RapidRobert
Re: holley jet size 35? - 11/19/14 04:09 AM
Quote:Oh Ok that makes sense
That's because that box is the performance jetting,not applicable to one and two barrel carbs.
Posted By: viperblue72
Re: holley jet size 35? - 11/19/14 04:37 AM
Quote:Quote:Oh Ok that makes sense
That's because that box is the performance jetting,not applicable to one and two barrel carbs.
Yeah, but thanks for sharing, as I was just looking at prices for those assortment kits earlier and considering one.
I have to order jets online as the local parts stores aren't carrying holley jets like they used to.
Posted By: viperblue72
Re: holley jet size 35? - 11/19/14 05:49 AM
Just filled up after driving only 65 miles. That was with a top speed jaunt for about 5 miles and letting the truck warm up the last few mornings for 15 minutes each. Still 11mpg. 
Time to hit up jegs.
Time to hit up jegs.
Posted By: dogdays
Re: holley jet size 35? - 11/19/14 06:20 PM
My 570 Street Avenger is running 54s in front. But the lowest altitude I see is 4300 ft. Some of the 650 spreadbores went as low as 50s on the primary side, IIRC.
R.
R.
Posted By: viperblue72
Re: holley jet size 35? - 11/19/14 07:15 PM
My 11 second duster with 4.11s and 408 stroker got better mileage than this.
Posted By: viperblue72
Re: holley jet size 35? - 12/01/14 03:56 AM
Ok some of you asked for an update. I decided to just put a 51 jet in. I am now getting 17 mpg.
It has less power than with the bigger jet but still runs good. I may try the 53 and see how it does.
It has less power than with the bigger jet but still runs good. I may try the 53 and see how it does.
Posted By: B5 Bee
Re: holley jet size 35? - 12/26/14 04:00 AM
Well, this may be too late to help, but I finally took apart the 1920 off my '68 V200, it had a #55 in it.
It was stamped on the side like every one of the 40 or so Holley jets that I have, not the end or face.
It was stamped on the side like every one of the 40 or so Holley jets that I have, not the end or face.