Need help finalizing carb/ignition choice, 2.0 8.5:1 CR, Euro 94mm pistons, 44 IDFs, unk Street carb cam |
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Need help finalizing carb/ignition choice, 2.0 8.5:1 CR, Euro 94mm pistons, 44 IDFs, unk Street carb cam |
Moneypit |
May 1 2014, 01:12 PM
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#1
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Member Group: Members Posts: 195 Joined: 4-January 06 From: Georgetown, TX Member No.: 5,360 Region Association: Southwest Region |
After spending the last few days on Google, 914World, Pelican, ShopTalk, and wherever else, I think I've got an idea of what I need to do with my carbs, but I wanted to validate my findings first. There are still some unknowns again on the motor, as the original rebuild specs went AWOL. We are still digging for them!
To start, motor is a 2.0 with Euro pistons. Before rebuild, compression was extremely high for pump gas and blew head gaskets out. Motor has a cam for carbs, but since I can't find the specs for it, let's briefly assume it's equivalent to whatever WebCam's street carb cam is. Not a super agressive cam from what I remember, just that Dan said it was definitely a carb for cams and would work well for the motor. Compression was brought down to a little more than stock but should be fine on pump, especially if I just run premium as I expected to anyways. Current 44 IDFs on the car are the later Spain mfg. I don't know what's inside them as far as jets, but I'm going to assume they are running out-of-the-box 914 kit, as the poor bottom end seems to match the description based on my memory. Second set of 44 IDFs appear to be original Italian mfg. They have 36 Venturi, 175 air, unk emulsion, unk idle, 50 pump jets. My plan is to rebuild and use the Italian made set. I am lining up all the jets and vents based on a 2007 thread, and wanted to verify these numbers are still correct based on your experiences and whatever developments between now and then: $8.95 ea x4 32mm venturi 32 Vent @ CB $15.95 ea x4 F 7 emulsion tube F7 emulsion @ CB $3.95 ea x4 2.00 air correction jets 2.00 Air correction jets @ CB $3.95 ea x4 .50 idle jets .50 Idle Jets @ CB $3.95 ea x4 1.30 main jets 1.30 Main Jets @ CB Where my additional questions come in are regarding to other jets/bits on the 44 IDF. I didn't see anything about the following parts: Pump Jet: Exhaust Jet (in bottom of fuel bowl, has a little ball in it?): Inlet Valve (one that hooks to the float): http://www.cbperformance.com/ProductDetail...roductCode=6368 Also looking for float settings! In addition to rebuilding and properly configuring the carbs themselves, getting new hoses, re-evaluating the fuel pump, and the revised carb pulley linkage, I need advice on igniting this whole thing. Currently, I don't know which distributor it has but it isn't a Mallory, and it's running a Bosch blue coil. If I upgrade to a Mallory, whats the best way to spark it? Stick with the Bosh blue, or is there a multi-spark that mates well with the Mallory? |
HarveyH |
May 1 2014, 03:27 PM
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#2
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Member Group: Members Posts: 450 Joined: 19-June 03 From: Downingtown, PA Member No.: 843 |
Back 15 years or so ago when I first bought my car (already cammed and carbed) I did some research (pre internet...) phoning various Weber parts suppliers. All of their recommendations began with multi-spark ignition. I'm currently running a Pertronix in a stock 74/2.0 distributor, Crane HI-6 multi-spark and the Crane PS-91 coil. I've also had to add the Crane tach adapter. Standard heat range plugs opened to 0.044"
I am running IDF-40's with 28mm venturies so my jetting probably wouldn't be applicable to 44's. Hope this helps, Harvey |
r_towle |
May 1 2014, 06:05 PM
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#3
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Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Get the car
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Kirmizi |
May 1 2014, 08:09 PM
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#4
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Senior Member Group: Members Posts: 836 Joined: 12-February 06 From: Wyoming, US Member No.: 5,568 Region Association: None |
I'm running dual Webers with a Mallory dizzy and coil, and MSD-6A box.
Eric Shea (I think) had an excellent thread about setting up carbs, in addition to information about venturies, jets, etc... (IMG:style_emoticons/default/biggrin.gif) |
Moneypit |
May 2 2014, 07:14 AM
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#5
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Member Group: Members Posts: 195 Joined: 4-January 06 From: Georgetown, TX Member No.: 5,360 Region Association: Southwest Region |
I'm running dual Webers with a Mallory dizzy and coil, and MSD-6A box. Eric Shea (I think) had an excellent thread about setting up carbs, in addition to information about venturies, jets, etc... (IMG:style_emoticons/default/biggrin.gif) Any linkies on your setup? Curious what the 6A does, how does it all work for you? |
r_towle |
May 2 2014, 07:19 AM
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#6
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Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
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Moneypit |
May 2 2014, 08:05 AM
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#7
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Member Group: Members Posts: 195 Joined: 4-January 06 From: Georgetown, TX Member No.: 5,360 Region Association: Southwest Region |
Read through MSD's page and install guide, looks pretty straightforward. So Mallory + Mallory Coil + MSD 6A provides a dizzy with a good advance curve for the motor, and multi-spark below 3k RPM. Hopefully that combined with the right carb settings will get the car running more smoothly so my folks can at least use it as a 2nd car. Otherwise the 914 just takes up space and is more likely to be let go before I can "buy it back".
I'm going to hit the search again to try and find more old threads. I'm still looking for more on the pump jets, exhaust jet, and floats. |
Kirmizi |
May 2 2014, 11:33 AM
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#8
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Senior Member Group: Members Posts: 836 Joined: 12-February 06 From: Wyoming, US Member No.: 5,568 Region Association: None |
Plenty of info on the forum, it's what I used to set mine up. (IMG:style_emoticons/default/biggrin.gif)
Here's a couple of links I had bookmarked for carb jetting/tuning: http://www.914world.com/bbs2/index.php?sho...ic=89838&hl http://www.914world.com/bbs2/index.php?sho...ir+bypass+screw |
Moneypit |
May 2 2014, 11:40 AM
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#9
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Member Group: Members Posts: 195 Joined: 4-January 06 From: Georgetown, TX Member No.: 5,360 Region Association: Southwest Region |
So, apparently the Mallory units ain't what they used to be... what happened? Did they go to crap in 2007? We don't have an infinite budget to get this car going right now and I need to make sound decisions. Do I just get one and screw with it till it works?
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r_towle |
May 2 2014, 11:48 AM
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#10
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Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
if you are running carbs, and you are looking for an occasional daily driver, it may be in your best interest to look into going back to fuel injection.
I was under the impression that you were taking possession of the car and would be building it as you want... While carbs are great, they need to be monitored for cleanliness all the time. The current type of fuel we have available tends to gum up pretty quick and will make a carburated car less reliable then you might want. If reliability, occasional use, and a get in and drive it to the store or on a weekend drive is what you are looking for, there would be no question in my mind that the stock fuel injection is the way to go. Its simple to put in, it will be up and running in less than a day, and you can buy everything you need from this 914World group over a couple of weeks. Add in some electronic optical sensor in place of the points, and you will have a reliable car for many years to come. If you wanna have fun, race, autox, and love tinkering.... Stick with Carbs, aftermarket ignition, and all the issues that go with that. rich |
Moneypit |
May 2 2014, 12:07 PM
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#11
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Member Group: Members Posts: 195 Joined: 4-January 06 From: Georgetown, TX Member No.: 5,360 Region Association: Southwest Region |
if you are running carbs, and you are looking for an occasional daily driver, it may be in your best interest to look into going back to fuel injection. I was under the impression that you were taking possession of the car and would be building it as you want... While carbs are great, they need to be monitored for cleanliness all the time. The current type of fuel we have available tends to gum up pretty quick and will make a carburated car less reliable then you might want. If reliability, occasional use, and a get in and drive it to the store or on a weekend drive is what you are looking for, there would be no question in my mind that the stock fuel injection is the way to go. Its simple to put in, it will be up and running in less than a day, and you can buy everything you need from this 914World group over a couple of weeks. Add in some electronic optical sensor in place of the points, and you will have a reliable car for many years to come. If you wanna have fun, race, autox, and love tinkering.... Stick with Carbs, aftermarket ignition, and all the issues that go with that. rich It's...complicated. The car is the second one we got for me in High School, and is still technically in mom's name (which she does like to remind me of every time I bring up all these things I want to do to it). And their situation right now is that with the Astro down for the count (still in Az), they have one car. They're fine having me do stuff to it, she just doesn't want me starting a massive rebuild that ends up having the car totally out of comission for the forseeable future. I'm happy working on it because I have an emotional attachment to the car, whether my name is on the title or not. As it stands right now, the goal is get the car inspectable and registered, so if a situation arises the 914 can be used since they only have the 4 Runner otherwise. We visit them at least weekly, if not bi-weekly, so I'll be taking oportunities to take the 914 out to keep her exercised. We collectively do not have the $$$ right now to go back to stock FI, and I'm not sure I'd want to at this point. Part of the $$$ factor right now is that we just bought a house, have an 11 month old, are planning a second to start this fall, and my dad's contract may be up later this year for work. So we are doing our best to keep initial costs down to get her on the road, so we can decide on long-term future. Long term would be me buying it back from them, though that plan has me under fire from the wife already. Which brings me to another technical development: Dan didn't have the actual engine build sheet, but he did have a copy of the work order. The motor was built back to stock tolerances, but a bump to 8.5:1 CR. He also noted that the distributor timing was set to 32 degrees full advance, so I've gone back to see what type of dizzy was used, or what he might have used if he can't remember. It has been 10 years afterall (IMG:style_emoticons/default/biggrin.gif) No notes on the cams, but I do remember in discussion that it did have a good cam in it. What's a typical lift/duration for a mild street carb cam? |
r_towle |
May 2 2014, 03:40 PM
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#12
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Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
so, with not alot of money....stick with simple.
It did run. Make it run again. No need to spend any more money than the following. Plugs NEW plug wires Points Distributor cap Rotor Oil Oil filter Fuel filter One can of carb cleaner Go give it a tune up. Also Remove the jets and clean all of them, the mains and the idle jets. Clean them with Carb cleaner. Start the car and drive it...with a new fresh tank of premium fuel. Dump all the old fuel out before you change the fuel filter. Enjoy the car. There is probably alot of little things you will need to chase down, like rubber fuel lines, rusty brakes, tires, muffler leaks etc. Dont spend any money to upgrade anything until you have a running and driving car....because you may need what little money you can spend to get it running right. Rich |
Moneypit |
May 2 2014, 03:56 PM
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#13
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Member Group: Members Posts: 195 Joined: 4-January 06 From: Georgetown, TX Member No.: 5,360 Region Association: Southwest Region |
so, with not alot of money....stick with simple. SNIP There is probably alot of little things you will need to chase down, like rubber fuel lines, rusty brakes, tires, muffler leaks etc. Dont spend any money to upgrade anything until you have a running and driving car....because you may need what little money you can spend to get it running right. Rich Haha, don't even get me started on my master list of all the things it needs (and that I want!) Yes, the motor does run. But just looking at it while it idles, the drivers side of the motor shakes much harder than the other, and it is awful off idle. Takes a good while before it wants to idle. That's why I wanted to start out of the gates with a solid choice of vents and jets. What I've narrowed things down to: 1) Leaving the dizzy alone, has a Bosch Blue coil right now. 2) Going to do a rebuild kit on both carbs. 3) Going to drop vent size to 32, might try the printed ones to see if that helps and get metal ones later. 4) Going to order the jets and stuff thru Aircooled.net and see if they have any further recommendations based on what I do know about the motor. 5) Going to replace all the fuel lines I can get to with less ethanol suceptible ones. 6) Going to verify fuel pump type and flow, make sure it's not over 3 PSI. 7) Tune! I've read all the instructions a bunch of times, so I'll get a carb meter and get them dialed in as best I can!!! Might need to borrow one if anyone in TX has one they aren't using. If not I'll just get it from Aircooled.net While we goof with the motor, I need to re-key all the locks due to parts swapping after some swap meets. When that's GTG, I'll address the horn pad that's flopping around and honking all the time, and she should pass a Tx inspection! |
r_towle |
May 2 2014, 04:06 PM
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#14
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Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Leave your carbs alone
Just remove the jets and clean them. Remember, it ran before....so it will run again. Vents and jets may be correct...so don't go messing with anything until you have done the basics. Tuneup Replace fuel lines Verify fuel pressure. Then I would suggest you learn how to sync the carbs....this is all linkage adjustments....still no messing with the carbs. A very simple thing to do right now is clean the idle jets. Remove them, spray them with carb cleaner, put them back in. No need to take apart the holder and the jet....it's simple to spray them as they come out.. The idle jet it THE first thing to suspect when the car starts to run odd anywhere below 3k rpms..... |
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