jetting 45 DCOE for 1700 turbo motor
-
volksnut
- Posts: 1167
- Joined: Tue Jun 26, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
I need help with Venturi , jetting, emulsion tubes etc. for a 1700, with C35 cam, 1.25 rockers, 044 heads (40x35.5 valves) 7.3 compression. The carb I bought didn't have any jets etc. in it to even start to figure things out! HELP!
-
Miker76
- Posts: 23
- Joined: Mon Jun 04, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
Sorry I have no answer for you but maybe you can help me? How much fuel pressure and what type of electric fuel pump should be used for a 40mm dcoe on a 1776 turbo?
Thanks
Mike
Thanks
Mike
-
Muffler Mike
- Posts: 3186
- Joined: Tue Feb 20, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Miker76:
<B>Sorry I have no answer for you but maybe you can help me? How much fuel pressure and what type of electric fuel pump should be used for a 40mm dcoe on a 1776 turbo?
Thanks
Mike</B><HR></BLOCKQUOTE>
I can only give you an example of what I helped with on my buddy Jim?s car. He had a holley red pump, a ?8 line (1/2?)going to the back this supplied his 40dcoe on a 1915 running 15lbs of boost. We started out with the usual 3 lbs when we first started to play with it and ran 10 lbs of boost. But as we turned it up a bit, I worried. So what I did was get the car to idle, then slowly turn up the fuel pressure until the motor bobbled, then back off just a touch. This ended up using around 4 ½ lbs of fuel pressure. We ran this with no enrichment set up or raise in fuel pressure under boost. The down side was I don?t remember what size needle and seat was in it. what I would do is find the biggest one you can. And turn up the fuel pressure as high as possible. All this was good for some 12.20 passes in a 1900 lbs car. If you try this pressure up at idle deal, you may want to have a switch to shut off the fuel pump. Otherwise when you turn on the key and you leave it too long, the pressure may overcome the needle and seat and flood the motor and then you cant start it. My ritual when I used his car, or his motor in my car, and even my car today. Turn ignition on, flip on fuel pump until I hear the pump go under pressure, then shut off. Start car and then turn pump back on.
------------------
Muffler Mike
www.MufflerMike.com
<B>Sorry I have no answer for you but maybe you can help me? How much fuel pressure and what type of electric fuel pump should be used for a 40mm dcoe on a 1776 turbo?
Thanks
Mike</B><HR></BLOCKQUOTE>
I can only give you an example of what I helped with on my buddy Jim?s car. He had a holley red pump, a ?8 line (1/2?)going to the back this supplied his 40dcoe on a 1915 running 15lbs of boost. We started out with the usual 3 lbs when we first started to play with it and ran 10 lbs of boost. But as we turned it up a bit, I worried. So what I did was get the car to idle, then slowly turn up the fuel pressure until the motor bobbled, then back off just a touch. This ended up using around 4 ½ lbs of fuel pressure. We ran this with no enrichment set up or raise in fuel pressure under boost. The down side was I don?t remember what size needle and seat was in it. what I would do is find the biggest one you can. And turn up the fuel pressure as high as possible. All this was good for some 12.20 passes in a 1900 lbs car. If you try this pressure up at idle deal, you may want to have a switch to shut off the fuel pump. Otherwise when you turn on the key and you leave it too long, the pressure may overcome the needle and seat and flood the motor and then you cant start it. My ritual when I used his car, or his motor in my car, and even my car today. Turn ignition on, flip on fuel pump until I hear the pump go under pressure, then shut off. Start car and then turn pump back on.
------------------
Muffler Mike
www.MufflerMike.com
-
Muffler Mike
- Posts: 3186
- Joined: Tue Feb 20, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by volksnut:
I need help with Venturi , jetting, emulsion tubes etc. for a 1700, with C35 cam, 1.25 rockers, 044 heads (40x35.5 valves) 7.3 compression. The carb I bought didn't have any jets etc. in it to even start to figure things out! HELP!<HR></BLOCKQUOTE>
I?m going to take a wild guess based on what was in Jim?s car.
Using a 33 venturi we were at a 165-170 main 200 air. On an f-7 emulsion.
I would say an f7 or f-11 would be ok.
Lets say you would use a 38 vent because of carb size. I would say maybe try a 185-195 main on the 200 air. This is all just a wild guess on my part. I am assuming that the aux. venturi that deliver the fuel in the middle react the same way on the smaller carb. It is very possible that when they change carb size they also change the characteristics of the aux. venturi as well. but I have no idea.
I would say you would be better off starting out rich and working down. Be prepared to spend a few bucks on different jets. Airs, mains, emulsions are the same as the idf and ida jets, so if you have a friend with these, you can borrow, till you find what you need and then buy. Caution, the idles are not the same. Although they do fit, the dcoe has a small hole on the side of the jet it self. What I did for jims car was to take a pair of my ida idle jets that were small and I knew I would not use them, and drilled a 100 hole in the side and finally worked my way up to a 120 on the side to make it work as we started out to rich on the idle.
Or just put a holley on it, spend 30 bucks on 36 pairs of jets instead of 5 bucks a piece.
The other options if you cant get a strait answer out of any one. Call up Kawell, send your carb to him, let him check and prep and pre-jet the carb and get it fairly close to begin with. This is what jim did with the carb I donated to the cause. We only changed the idles from what Kawell sent it back with and bumped to the 170 when we turned up the boost. But it was close enough to bolt on and drive it.
------------------
Muffler Mike
www.MufflerMike.com
[This message has been edited by Muffler Mike (edited 10-17-2001).]
I need help with Venturi , jetting, emulsion tubes etc. for a 1700, with C35 cam, 1.25 rockers, 044 heads (40x35.5 valves) 7.3 compression. The carb I bought didn't have any jets etc. in it to even start to figure things out! HELP!<HR></BLOCKQUOTE>
I?m going to take a wild guess based on what was in Jim?s car.
Using a 33 venturi we were at a 165-170 main 200 air. On an f-7 emulsion.
I would say an f7 or f-11 would be ok.
Lets say you would use a 38 vent because of carb size. I would say maybe try a 185-195 main on the 200 air. This is all just a wild guess on my part. I am assuming that the aux. venturi that deliver the fuel in the middle react the same way on the smaller carb. It is very possible that when they change carb size they also change the characteristics of the aux. venturi as well. but I have no idea.
I would say you would be better off starting out rich and working down. Be prepared to spend a few bucks on different jets. Airs, mains, emulsions are the same as the idf and ida jets, so if you have a friend with these, you can borrow, till you find what you need and then buy. Caution, the idles are not the same. Although they do fit, the dcoe has a small hole on the side of the jet it self. What I did for jims car was to take a pair of my ida idle jets that were small and I knew I would not use them, and drilled a 100 hole in the side and finally worked my way up to a 120 on the side to make it work as we started out to rich on the idle.
Or just put a holley on it, spend 30 bucks on 36 pairs of jets instead of 5 bucks a piece.
The other options if you cant get a strait answer out of any one. Call up Kawell, send your carb to him, let him check and prep and pre-jet the carb and get it fairly close to begin with. This is what jim did with the carb I donated to the cause. We only changed the idles from what Kawell sent it back with and bumped to the 170 when we turned up the boost. But it was close enough to bolt on and drive it.
------------------
Muffler Mike
www.MufflerMike.com
[This message has been edited by Muffler Mike (edited 10-17-2001).]
-
Miker76
- Posts: 23
- Joined: Mon Jun 04, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
Muffler Mike, you are the KING! Thank you for the info. I guess you had an adjustable fuel pressure regulator? Also, the 15 lbs of boost wasn't on pump gas, was it? 12.20's wow. I cant wait for my car to be ready. I can get a Holley pressure regtulator easily localy but Is it true I should spend the extra money and mail order a rising rate fpr?
Thanks
Mike
Thanks
Mike
-
Lo Cash John
- Posts: 1089
- Joined: Thu Jun 14, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
You can make your own rising rate regulator by drilling/tapping and installing an 1/8th npt hose barb on the upper housing of the Holley regulator. Run a hose from the hight pressure side of the turbo manifold to the regulator and that's about it. If you end up with an intake leake from sucking air in around the set-screw, you have two fixes:
1 . Install an in-line oneway check valve(pressure can go to regulator, but closes on vacuum so no intake leak)
2. Smear a little RTV silicon around the set screw (and the little notch by the set screw)so no air can get in.
1 . Install an in-line oneway check valve(pressure can go to regulator, but closes on vacuum so no intake leak)
2. Smear a little RTV silicon around the set screw (and the little notch by the set screw)so no air can get in.
-
Miker76
- Posts: 23
- Joined: Mon Jun 04, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
Thank you very much for your reply. I didnt realise the holley has the right internal (diaphram??) to allow the boost to actually affect it. Thanks again, The holley regulator is pretty low priced too!
Mike
Mike
-
Muffler Mike
- Posts: 3186
- Joined: Tue Feb 20, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Miker76:
<B>Muffler Mike, you are the KING! Thank you for the info. I guess you had an adjustable fuel pressure regulator? Also, the 15 lbs of boost wasn't on pump gas, was it? 12.20's wow. I cant wait for my car to be ready. I can get a Holley pressure regtulator easily localy but Is it true I should spend the extra money and mail order a rising rate fpr?
Thanks
Mike </B><HR></BLOCKQUOTE>
I could have sworn I answered back the other day. Guess I had a brain fart.
Any way, yes it was an inexpensive regular holley regulator. It was not set up to apply extra pressure under boost.
But like John said, its really that simple if you wanted to do it. so you don?t need any thing fancy.
At 10 lbs of boost we ran pump gas. But when we stepped up the 15 we then used good gas. (VP red)
------------------
Muffler Mike
www.MufflerMike.com
<B>Muffler Mike, you are the KING! Thank you for the info. I guess you had an adjustable fuel pressure regulator? Also, the 15 lbs of boost wasn't on pump gas, was it? 12.20's wow. I cant wait for my car to be ready. I can get a Holley pressure regtulator easily localy but Is it true I should spend the extra money and mail order a rising rate fpr?
Thanks
Mike </B><HR></BLOCKQUOTE>
I could have sworn I answered back the other day. Guess I had a brain fart.
Any way, yes it was an inexpensive regular holley regulator. It was not set up to apply extra pressure under boost.
But like John said, its really that simple if you wanted to do it. so you don?t need any thing fancy.
At 10 lbs of boost we ran pump gas. But when we stepped up the 15 we then used good gas. (VP red)
------------------
Muffler Mike
www.MufflerMike.com
-
Miker76
- Posts: 23
- Joined: Mon Jun 04, 2001 12:01 am
jetting 45 DCOE for 1700 turbo motor
Thank you very much for your reply. Your advice means a whole lot to me. Until next time, goodbye.
Mike
Mike