1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Doing it. Converting my SE to weber power!

Thread Tools
 
Search this Thread
 
Old Nov 7, 2011 | 01:51 PM
  #51  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
The carb is more appealing to me in the end.

And since I've already decided I don't see how EFI discussion is relevant to this thread.
Reply
Old Nov 7, 2011 | 10:16 PM
  #52  
j9fd3s's Avatar
Moderator
Community Builder
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Mar 2001
Posts: 31,835
Likes: 3,232
From: https://www2.mazda.com/en/100th/
Originally Posted by Starfox07
Ok awesome. The unknown I believe is actually for the (non functioning) windshield washers.
or there is cruise control and a vacuum switch over there too. i'm not sure off the top, but if you follow it, it should be pretty obvious.

and yeah you could just hook the vacuum advances up to intake vacuum, timing will be more advanced at idle than normal, but that's ok. i'd still tune the carb first, just cause its simpler. one thing at a time
Reply
Old Nov 7, 2011 | 11:38 PM
  #53  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Alright. I'm reading all I can about the DCOE and how to tune it. Anyone have good links? I'm kind of excited about learning the 'forgotten art' of carb tuning, another reason I'm preferring it to EFI at this stage.
Reply
Old Nov 8, 2011 | 12:41 PM
  #54  
j9fd3s's Avatar
Moderator
Community Builder
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Mar 2001
Posts: 31,835
Likes: 3,232
From: https://www2.mazda.com/en/100th/
try http://www.expeditionlandrover.info/...erDCOEinfo.htm
Reply
Old Jan 5, 2012 | 08:59 PM
  #55  
rotarycrazy's Avatar
Leave my avatar alone!!!
Tenured Member 20 Years
iTrader: (8)
 
Joined: Feb 2005
Posts: 1,656
Likes: 0
From: Spartanburg SC
where are you getting a 48 dcoe from? I am planing on doing a similar setup but also planing on making the 5th and 6th ports work with some solenoids and an rpm switch.
Reply
Old Jan 5, 2012 | 09:03 PM
  #56  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Well I've had to the project on hold until the summer. Unexpected things came up. I've bought the intake manifold and a few other assorted bits, but not the carb yet. Not sure where I will buy from when the time comes.
Reply
Old Aug 21, 2012 | 03:55 PM
  #57  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Resuming this project, still tired of crappy stock EFI.

I'm trying to put together a shopping list of parts:

1. Weber/Dellorto 45/48 Sidedraft
2. Weber sidedraft intake manifold [purchased]
3. Mallory return style FPR
4. Throttle bracket
5. Filter assembly
6. Inline fuel pressure gauge
7. Misc fuel hose

Can you guys think of anything else?

I'm obviously in the market for a sidedraft 45 or 48 carb, so if anyone has one they would like to part with, I'm ready to purchase.

I now have a 2012 Mazda2 which gets 40mpg so gas mileage on my RX-7 is totally irrelevant.
Reply
Old Aug 21, 2012 | 04:18 PM
  #58  
TheRX7Project's Avatar
Daily Beaten
Tenured Member 10 Years
iTrader: (3)
 
Joined: May 2008
Posts: 592
Likes: 3
From: Milwaukee
I would seriously consider an aftermarket fuel pump and fuel pressure regulator, and a fuel pressure gauge. Good ones. The Summit setup I have was like $100, plus a screw-in fuel pressure gauge which was about $20. Consider it "engine insurance".
Reply
Old Aug 21, 2012 | 04:38 PM
  #59  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Well I have a high pressure fuel pump already (GSL-SE remember) and a Mallory FPR + FP gauge is already on my list.
Reply
Old Aug 21, 2012 | 05:28 PM
  #60  
dbragg's Avatar
Say hello to Mr.Wankel
Tenured Member 05 Years
iTrader: (7)
 
Joined: Nov 2004
Posts: 5,962
Likes: 1
From: Cartersville, Ga
We just did a motor swap in my buddies SE a few weeks ago. Initially it was running on stock motor and FI. We swapped in a ported 4 port and swapped it over to a Dellorto 48.

Here is all you will need (taking into consideration you already have a Weber manifold):

Carb
filter assembly
throttle bracket*
FPR (I highly suggest a Mallory 4309)
FP gauge (get a McDaniels)
a few feet of 5/16" fuel line
*possibly a 12a throttle cable

*The SE throttle cables sheath was too short, but the cable length was fine, for the RB(?) throttle cable on the dellorto. So we just extended the bracket a few inches to fix the problem. Another solution would have been to swap in a 12a throttle cable. This will depend on the throttle bracket you get/make.

Also, if you have a 1 piece Weber manifold, that doesn't utilize the lower stock manifold, then you will need to remove the 5th and 6th ports, which is easy when the manifold is removed. You will also need to make sure your manifold has a nipple for the brake booster, and anything else you want to attach to it (vacuum advance, crankcase vent, etc.)

Then just look under the carpet in the passenger side floor board and you will see a shield held in by four bolts. Remove the shield and it will expose the ECU and other electronic goodies. You can pull the engine harness out through the firewall, disconnect it from everything, and remove it from the car, along with the ECU and everything(it's all attached to one bracket so it's really easy). Now, due to how the GSLSE fuel pump works you will have to bypass the circuit opening relay (I believe is what it's called). It's the only relay you see down there. You just need to put a jumper from the BW and L wires, and they're side by side. Now the fuel pump will come on whenever the key is in accessory, where as it wouldn't before. Dial in your FPR and carb and you're good to go.

I may have forgotten something, but I just recently went through this and it's fresh on my mind, so just ask if you have questions.
Reply
Old Aug 21, 2012 | 05:38 PM
  #61  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Wow. That is a beautiful post. Thank you very much

How is his car running?
Reply
Old Aug 21, 2012 | 08:45 PM
  #62  
dbragg's Avatar
Say hello to Mr.Wankel
Tenured Member 05 Years
iTrader: (7)
 
Joined: Nov 2004
Posts: 5,962
Likes: 1
From: Cartersville, Ga
Awesome. He has been driving it a lot since the swap, about three weeks. I also drove it to his house after the swap, so I got to test it out in the city and on the highway. Honestly, the dellorto was awesome under all conditions, even highway cruising, and would pull hard if you opening it up or just needed to change lanes. It also has an 11 pound flywheel and could use a little tweaking with the tune, so it kind of sucked off the line starting on a hill, but that's the only thing I didn't like. In all other aspects it was just as calm and docile as the FI, but pulled MUCH better when accelerating. Don't forget though, his also came with an engine swap to a 4 port 13b that's street ported and has S5 NA rotors, but I would think you would definitely notice a gain as well.

Depending on how things play out with this wide body SE I have sitting downstairs in my basement, I may be swapping in his old SE 13B and a dellorto relatively soon. If/when I do, I will let you know how it compares.
Reply
Old Aug 21, 2012 | 10:42 PM
  #63  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Awesome. I've also been eyeing the RB 13lb flwheel. If there is one thing I love in this world, it's throttle response.
Reply
Old Aug 23, 2012 | 11:26 AM
  #64  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Would this FP gauge work well? It's the cleanest face I can find, and it's not liquid filled.

Holley 26-500 - Holley Analog Fuel Pressure Gauges - Overview - SummitRacing.com

I would be mounting this in the engine bay, near the carb, correct?
Reply
Old Aug 28, 2012 | 11:19 AM
  #65  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
I've located a carb, and it will most likely need to be rebuilt and possibly rejetted. Is the rebuilding something difficult or requiring special tools? I'm pretty good mechanically, so I think I can handle it.

One final question: Will the OMP work just as it did before the removal of the upper intake manifold? I've got a pretty good handle on everything else, but I don't really know about the OMP.






For future reference and anybody stumbling upon this thread via google search or something like that, here is a fantastic source of info on the dellorto 48 DHLA on a stockport 13b:

Gruntled.com - Dellorto - Jetting

13B Instructions

Seems like racing beat did not even bother with the vacuum advance, so I will not either.
Reply
Old Aug 28, 2012 | 11:37 AM
  #66  
j9fd3s's Avatar
Moderator
Community Builder
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Mar 2001
Posts: 31,835
Likes: 3,232
From: https://www2.mazda.com/en/100th/
90% of rebuilding the carb is super simple, the hard part is making sure the moving parts work consistently. the weber doesn't really need any special tools, although a little creativity might be required.

the OMP stays untouched with a dell setup, except you need to find a spot for the vacuum feed, if its in the RB instructions just follow that.

for the vacuum advance, i'd leave it like RB has it and then maybe once its tuned try it again
Reply
Old Aug 28, 2012 | 11:51 AM
  #67  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Originally Posted by j9fd3s
90% of rebuilding the carb is super simple, the hard part is making sure the moving parts work consistently. the weber doesn't really need any special tools, although a little creativity might be required.

the OMP stays untouched with a dell setup, except you need to find a spot for the vacuum feed, if its in the RB instructions just follow that.

for the vacuum advance, i'd leave it like RB has it and then maybe once its tuned try it again
One part confuses me. The lever that connects from the OMP to the throttle body will obviously be different when there is no throttle body. So how will the OMP be controlled? I'm thinking about converting to premix...

edit: Also, I ended up going with a Dellorto and not a Weber. But they are essentially the same from what I've seen.
Reply
Old Aug 28, 2012 | 12:33 PM
  #68  
j9fd3s's Avatar
Moderator
Community Builder
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Mar 2001
Posts: 31,835
Likes: 3,232
From: https://www2.mazda.com/en/100th/
i think the RB carbs had the OMP linkage on the carb. or you can use a cable, like a bicycle cable, or premix

i'm pretty sure the dell and the weber are almost the same, i just don't have any recent experience with a dell!
Reply
Old Aug 28, 2012 | 01:04 PM
  #69  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Already ordered an OMP block off plate. I'm tired of looking at that nasty mess at the front of my engine anyways

At some point, I still want to do that rotary aviation oiling system, but at the present time, premix will do nicely. Can't wait to smell that sweet 2 stroke oil

Wow my CC has been getting a workout. Ordered the following in the past two days:

Mallory 4309 FPR [summit]
Professional Products 0-15psi fuel pressure gauge (mechanical) [summit]
OMP block off plate [mazdatrix]
LIM-to-block and UIM-to-UIM gaskets [rockauto]

and a few other things I can't remember :p
Reply
Old Aug 28, 2012 | 01:08 PM
  #70  
j9fd3s's Avatar
Moderator
Community Builder
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Mar 2001
Posts: 31,835
Likes: 3,232
From: https://www2.mazda.com/en/100th/
Reply
Old Aug 28, 2012 | 10:22 PM
  #71  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
Bought the carb and brought her home. I did a little investigating and it appears to be jetted right on the money for a stockport 13b, right down to the RB specifications. The carb seems to be in good shape, should I rebuild it anyways or try it out as is?
Reply
Old Aug 29, 2012 | 01:18 AM
  #72  
j_tso's Avatar
Rotary Freak
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Dec 2004
Posts: 1,972
Likes: 399
From: Austin, TX
At least check the float level and that they do float.
Reply
Old Aug 29, 2012 | 08:02 AM
  #73  
Starfox07's Avatar
Thread Starter
Environmentally-Hostile
Tenured Member 15 Years
 
Joined: Sep 2005
Posts: 1,662
Likes: 3
From: Ennis/Arlington Texas
I'm sort of new to the world of carburetors, do I check the float level by attaching the fuel line to the carb and giving it some fuel?
Reply
Old Aug 29, 2012 | 09:14 AM
  #74  
reo's Avatar
reo
Full Member
Tenured Member 05 Years
iTrader: (4)
 
Joined: Jun 2011
Posts: 102
Likes: 0
From: golden valley, az
good thread-- 13b with 48 weber sd
Reply
Old Aug 29, 2012 | 05:39 PM
  #75  
j_tso's Avatar
Rotary Freak
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Dec 2004
Posts: 1,972
Likes: 399
From: Austin, TX
Originally Posted by Starfox07
I'm sort of new to the world of carburetors, do I check the float level by attaching the fuel line to the carb and giving it some fuel?
Hold the top cover up sideways with the hinge on top with the floats closing the needle valve. The needle has a little spring loaded ball, don't have the floats rest on it so much that it's compressed. Then you measure the distance from the floats to the gasket.

Test the floats in a little cup of gasoline. I think Dellortos only had plastic ones, just make sure there are no holes in them.

foxed.ca has a pdf of a rebuid/tuning manual for Weber and Dellorto side drafts, as well as the old How to Modify Your RX-7 which has a nice section for tuning carbs on rotaries.
Reply



All times are GMT -5. The time now is 11:48 AM.