F.I. switch to carbs |
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F.I. switch to carbs |
karmanbuilt |
Feb 17 2009, 08:30 PM
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#1
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??? Group: Members Posts: 72 Joined: 7-July 08 From: Emmett, ID. Member No.: 9,262 Region Association: Pacific Northwest |
[size=1]After fighting the stock F.I. on my '76 2.0L, and lots of $$$ since 2002, time for carbs. I know all the talk about F.I. is better, I will lose power and milage. The stock cam is not set up for carbs...etc,etc. All I need to know is what changes need to be made to make the dual 40's happy and getting back on the road. Hope I have not up set all you die hard F.I. folks......
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SirAndy |
Feb 17 2009, 08:39 PM
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#2
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Resident German Group: Admin Posts: 41,676 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
[size=1]After fighting the stock F.I. on my '76 2.0L, and lots of $$$ since 2002, time for carbs. I know all the talk about F.I. is better, I will lose power and milage. The stock cam is not set up for carbs...etc,etc. All I need to know is what changes need to be made to make the dual 40's happy and getting back on the road. Hope I have not up set all you die hard F.I. folks...... Pretty simple, you'll need: - Carb Fuel pump. The rotary pump from CB performance is the best one i have seen. - Jumper your relay board to run the new fuel pump using the stock wiring. http://www.914world.com/bbs2/index.php?showtopic=25954 - Get a good crosslinkage for your carbs. Again, CBP has the good stuff. - Oil vapor catch can. Again, CBP. (I sound like a infomercial (IMG:style_emoticons/default/biggrin.gif) ) - Distributor. You'll hear a lot of opinions on that one. - Thick FI runner to head gaskets to insulate the runner from the hot heads. - Adjust valves before you try to sync the carbs. - Backdate the exhaust system and get SSI heat exchangers. That'll free up some HP. I'm sure there's more, but that'll get you started. (IMG:style_emoticons/default/bye1.gif) Andy PS: (IMG:style_emoticons/default/welcome.png) |
reverie |
Feb 18 2009, 04:07 AM
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#3
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Senior Member Group: Members Posts: 783 Joined: 14-March 03 Member No.: 427 Region Association: None |
If you need help with the carbs, there's a good VW hot-rod shop in Boise.
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JoeSharp |
Feb 18 2009, 05:01 AM
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#4
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In Irvine, Ca. May 15-18 Group: Members Posts: 3,947 Joined: 9-July 03 From: DeLand, Florida Member No.: 898 Region Association: South East States |
If you go with Solex singles you won't suffer from all of the preconsived stuff that everyone tells you. One of the Team NARP cars with a 1.7 got 49 MPG without trying and the drop in power is minamal. Today that car is going to be a 2L with the same carbs. I'm betting we can get it to get over 50 MPG. I run the same carbs on my 2110 Super Beatle and it smokes the tires in 1st and 2nd while getting about 35 on the street if I keep my foot out of it.
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gothspeed |
Feb 18 2009, 12:35 PM
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#5
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
If you go with Solex singles you won't suffer from all of the preconsived stuff that everyone tells you. One of the Team NARP cars with a 1.7 got 49 MPG without trying and the drop in power is minamal. Today that car is going to be a 2L with the same carbs. I'm betting we can get it to get over 50 MPG. I run the same carbs on my 2110 Super Beatle and it smokes the tires in 1st and 2nd while getting about 35 on the street if I keep my foot out of it. Good info there Joe .......... I am still pondering programable FI or Carbs on the 914 I haven't bought yet ......... (IMG:style_emoticons/default/wink.gif) |
karmanbuilt |
Feb 19 2009, 01:14 AM
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#6
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??? Group: Members Posts: 72 Joined: 7-July 08 From: Emmett, ID. Member No.: 9,262 Region Association: Pacific Northwest |
Hey.....thanks for the 411 on the switch to carbs. I know this question has been asked so many times. First 914 was '71 1.7L, and I left it stock with the F.I. no problems, sold it in 1996. My '76 has a hydraulic package so no valve adjustments, maybe the cam isn't stock.....unknown. Keeping the stock fuel pump, and adding a pressure regulator. Also keeping the dizzy, it's hooked up to a Comp-U-Fire....may work O.K.
P.S.-Sir Andy.....I could only hope my 2.0 was half as clean as yours.......now the big question.......which carbs???? |
So.Cal.914 |
Feb 19 2009, 07:49 AM
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#7
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"...And it has a front trunk too." Group: Members Posts: 6,588 Joined: 15-February 04 From: Low Desert, CA./ Hills of N.J. Member No.: 1,658 Region Association: None |
I have been running weber 40 IDF 's for many years. Very little problems.
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rhodyguy |
Feb 19 2009, 09:17 AM
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#8
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,090 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
you're planning on using the high pressure fi fuel pump, adding a regulator AND an ACURATE gauge? for what you'll spend on those items you can purchase the proper pump and be done with it. too many additional hose connections too.
k |
JoeSharp |
Feb 19 2009, 09:33 AM
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#9
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In Irvine, Ca. May 15-18 Group: Members Posts: 3,947 Joined: 9-July 03 From: DeLand, Florida Member No.: 898 Region Association: South East States |
Kevin's right, what ever carb you put in you need to get the C.B. rotary pump. BTDT on all the others including the stock with a return line. It causes problems when the tank is below half. I have used the other pumps and nothing works like the C.B.
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Bleyseng |
Feb 19 2009, 11:04 AM
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#10
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Aircooled Baby! Group: Members Posts: 13,035 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
Hey.....thanks for the 411 on the switch to carbs. I know this question has been asked so many times. First 914 was '71 1.7L, and I left it stock with the F.I. no problems, sold it in 1996. My '76 has a hydraulic package so no valve adjustments, maybe the cam isn't stock.....unknown. Keeping the stock fuel pump, and adding a pressure regulator. Also keeping the dizzy, it's hooked up to a Comp-U-Fire....may work O.K. P.S.-Sir Andy.....I could only hope my 2.0 was half as clean as yours.......now the big question.......which carbs???? The "hydraulic package" is why the djet didn't run too well...switching to carbs will help.....Now Ljet doesn't mind the hydro lifters. |
Tom |
Feb 19 2009, 11:46 AM
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#11
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Advanced Member Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None |
I'm not sold on the hydraulic package making the D-Jet run poorly. My 76 has hydraulics and D-Jet and runs great. Howeveer, I don't know what cam is installed with the hydraulic lifters. I know many here don't like the hydraulics, but I haven't had any problems with mine yet. I did back fit to the earlier SSHE's and a Triad exhaust system, so I may have gained back what was lost in power by installing the hydraulics.
Tom |
SirAndy |
Feb 19 2009, 12:01 PM
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#12
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Resident German Group: Admin Posts: 41,676 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
Keeping the stock fuel pump, and adding a pressure regulator. Please don't !!! (IMG:style_emoticons/default/icon8.gif) Attached image(s) |
karmanbuilt |
Feb 19 2009, 11:15 PM
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#13
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??? Group: Members Posts: 72 Joined: 7-July 08 From: Emmett, ID. Member No.: 9,262 Region Association: Pacific Northwest |
SirAndy........I spoke with an owner of a German shop, who told me I could use the stock F.I. fuel pump. Said just put a pressure regulator in line w/it.....guess I got the wrong info.
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Spoke |
Feb 20 2009, 06:39 AM
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#14
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Jerry Group: Members Posts: 6,991 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
Just out of curiosity, what is wrong the operation of your engine with FI? What items have you replaced?
I'm partial to FI since FI has provisions for cold engine operation and the cam is tuned for FI where carbs do not have engine and air temp sensors and the cam is not set up for carbs. When I bought my 71, it had a center progressive carb. The shop that did the work said they couldn't get the FI working so changed to carbs. A couple of years later when the shop moved, they gave me a box full of FI parts. I cleaned and checked each component and found the vacuum advance on the dizzy to have a huge vacuum leak. The MPS (D-Jet) also had huge vacuum leak. I bought a new dizzy, fixed the MPS leak, checked and cleaned everything, put it on the replacement engine for the 71, and it runs and runs good. If you changed a lot of parts but it still doesn't work right, then in general you haven't touched the one or two issues afflicting the engine. Vacuum leaks wreak havoc on FI. Have you checked for vacuum leaks with carb cleaner spraying everything like hoses, gaskets, etc., listening for a change in engine tone? I used a vacuum pump from HF for vacuum brake bleeding to check the MPS and Dizzy as well as hoses. |
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