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-   -   Doing it. Converting my SE to weber power! (https://www.rx7club.com/1st-generation-specific-1979-1985-18/doing-converting-my-se-weber-power-975331/)

Starfox07 09-04-12 03:01 PM

Spent yesterday stripping down and prepping the car for swapping the carb over next Mon/Tues. Shed probably 10-15lbs worth of EFI and Emissions equipment! Sweetness. Also removed those evil auxiliary port sleeves. No going back now. This thing is gonna scream on top end. :) Well, as much as a stockport can scream at least.

I've ordered the RB fuel injector block off (little pricey, but want a clean install) and now I want to block off the oil injectors. Bonzai racing makes a complete kit, but my credit card will not work on their site. Weird. Does anyone else make a complete kit? Or, conversely, does anyone know the exact size pipe plug for the housing injectors and bolt size for the LIM injectors? The information I've found is spotty, and I don't wanna risk trashing some apex seals with pipe plugs too long.

j9fd3s 09-04-12 03:09 PM


Originally Posted by Starfox07 (Post 11210440)
I don't wanna risk trashing some apex seals with pipe plugs too long.

you can't, the oil injectors are like a 10mm thread and the hole in the rotor housing is like 1mm.

the bolt DOES have to be short enough to have a washer on it, you can have a vacuum leak

project7s 09-05-12 09:36 PM

is there a reason you couldnt keep the 5th and 6th actuators and keep them working like they normally would so it wouldnt hurt your bottom end? also im assuming a weber and a dell will bolt up to the same rb intake, is there any real diff between the two worth noting?

clubber 09-05-12 10:19 PM

WOW. I'm spending gobs of time, money, and effort to go to EFI that this is amazing. My Maxton is an autocross car and my dellorto SUCKS in corners. The nikki wasn't much better and had way less power, but good luck with your project and I hope it turns out well for you.

Starfox07 09-05-12 11:19 PM


Originally Posted by project7s (Post 11211896)
is there a reason you couldnt keep the 5th and 6th actuators and keep them working like they normally would so it wouldnt hurt your bottom end? also im assuming a weber and a dell will bolt up to the same rb intake, is there any real diff between the two worth noting?

I do not have enough backpressure in my exhaust for them to work, I already tried. I might try to engineer some sort of linear actuator for them in the future, but for now bottom end isn't really that important. It's not a daily driver. Weber and Dell are essentially the same.

project7s 09-07-12 10:40 PM

im kinda thinking of doing this myself but with my rb exhuast my 5th 6th ports good so i would leave them hooked up, but i'm just kinda wondering how much more power adding a weber will give you if its really a huge difference verse the time and money it cost? does anybody have a horsepower comparsion stock verse weber?

Starfox07 09-08-12 02:06 AM


Originally Posted by project7s (Post 11214224)
im kinda thinking of doing this myself but with my rb exhuast my 5th 6th ports good so i would leave them hooked up, but i'm just kinda wondering how much more power adding a weber will give you if its really a huge difference verse the time and money it cost? does anybody have a horsepower comparsion stock verse weber?

With their exhaust, RB claimed a whopping 50% gain in power with their Dellorto 48 DHLA intake kit.

Even if they were exaggerating, there is still substantial gains to be had by simplifying the intake system. When the throttle plates are open on the Dell, there is almost ZERO restriction from the intake trumpets to the rotor face, it's basically an open path. The stock system cannot approach this level of flow and velocity.

Starfox07 09-08-12 02:39 AM

Took too long to edit my last post. The carb I bought I'm pretty sure was part of the RB kit, unfortunately it's missing a few things due to it's age. One thing I'm missing is a throttle bracket. Is this something I can fabricate easily? Or should I try to find an original one.

dbragg 09-08-12 08:27 AM

Depends on what resources you have available to you, or how much you want to pay someone else to do it. I would imagine it wouldn't be that difficult. Are you running the stock SE throttle cable? If so, the original one won't work and will need to be extended anyways, or you can get a 12a throttle cable and eliminate this issue. If you want an original, go to the source and call Racing Beat. My buddy I did the dellorto swap onto his SE was able to call and get some parts for his dellorto from them, so maybe you can get this as well.

j9fd3s 09-08-12 12:23 PM


Originally Posted by Starfox07 (Post 11214371)
Took too long to edit my last post. The carb I bought I'm pretty sure was part of the RB kit, unfortunately it's missing a few things due to it's age. One thing I'm missing is a throttle bracket. Is this something I can fabricate easily? Or should I try to find an original one.

on mine we used a toyota 22r throttle bracket, tweaked a little and its perfect and looks stock...

you could make something, its actually a fairly simple part

Starfox07 09-18-12 03:48 PM

Well I got everything mounted, plumbed, and otherwise hooked up. I turned the key to prime the pump and checked the FP gauge, and it was reading something like 5-6psi. I looked at the carb and fuel was running out of the air horns. Did I hurt the carb? I also had a few leaks from the regulator...I didn't use sealant on the fittings (guy at the parts store said it was unnecessary, why do I still listen to those clowns?) so I imagine that is the culprit.

I tried removing the jam nut on the FPR (mallory 4309) to adjust the fuel pressure, but I cannot for the life of me loosen that thing. I would likely rip the regulator right off of it's mount before the jam nut came lose. I don't know what to do. Do they really tighten them that much from the factory?

j9fd3s 09-18-12 04:15 PM


Originally Posted by Starfox07 (Post 11226593)
Well I got everything mounted, plumbed, and otherwise hooked up. I turned the key to prime the pump and checked the FP gauge, and it was reading something like 5-6psi. I looked at the carb and fuel was running out of the air horns. Did I hurt the carb? I also had a few leaks from the regulator...I didn't use sealant on the fittings (guy at the parts store said it was unnecessary, why do I still listen to those clowns?) so I imagine that is the culprit.

I tried removing the jam nut on the FPR (mallory 4309) to adjust the fuel pressure, but I cannot for the life of me loosen that thing. I would likely rip the regulator right off of it's mount before the jam nut came lose. I don't know what to do. Do they really tighten them that much from the factory?

if fuel is coming out of the air horns the float might be too high, won't hurt a thing unless it catches on fire. it should run but it'll be retardedly rich.

5-6 psi is a little high, i'd try to get between 4-4.5 and see what happens

j_tso 09-19-12 06:56 AM

Fuel coming out of the barrels could also mean the floats are sticking and therefore the needle isn't closing. Unlike the Weber, I can't see a way to poke the floats through the top cover to check if they're moving freely.

Also, are you using a new needle? An old one could have gunk in it preventing it from closing as well.

Starfox07 09-19-12 10:18 PM

I haven't touched the carb. Should I run some carb cleaner through it? It is used, but seems to be in pretty nice condition.

duffman692002 09-20-12 11:27 AM

Gunk on the needle generally require that ya remove it and get the trash out. In my experience carb cleaner will get the trash off the needle but it's still there and will catch again. Did you check the floats as j9 suggested?

Starfox07 09-21-12 08:29 AM

No sadly the car is 50 miles away at my parents house (only place I can work on it) and I can only work on it 2 days a week...and I won't even be able to this coming mon/tues :(

Does anyone have a manual/pdf online for the Dellorto DHLA. I was planning on getting a Weber originally, so I had a whole host of information ready, but the Del is a different animal. I need to learn about my carb so I can dial it in.

j_tso 09-21-12 11:50 AM

Foxed.ca

There's a manual there that covers both DCOE and DHLA rebuilding and tuning.

Starfox07 09-22-12 11:05 PM

Thanks, I will start reading up!

Starfox07 09-27-12 11:57 AM

Well got my fuel leakage issues figured out, and I thought, what the hell why not try and start it.

To my surprise it started right up after I cleared all the fluid out! The throttle response is absolutely insane compared to the stock EFI, and the induction roar is everything I could have ever wanted. I still don't have the throttle hooked up so I was doing a little hand job action on the carb.

Of course, it wasn't without issue.

I can't get my FPR to pull a steady fuel pressure. It jumps back and forth between 1-4psi and I can hear the fuel pump pulsing with it (bop bop bop bop). Any idea what could cause this?

Also, while the idle is pretty much dead on the money (about 850rpm) the car idles fine for about 15 seconds and then dies. I'm assuming this is probably a fuel supply issue? What else might it be? Again, I'm new to the world of carbs, so maybe the float level is set wrong?

All in all, I'm pretty excited. I thought I was going to have to spend days tuning just to get it to run for the first time.

That bark from the velocity stacks, hnggggggg...you EGI guys are really missing out....

j9fd3s 09-27-12 12:06 PM

re the idle, mine does that when its a little too lean. you don't need a wideband to set the idle, but i'll use AFR's to make my point. a stock port will idle at any AFR between 13:1 and 10:1, however when you get lean, the idle can get weak.

the short part is that you need to play with the idle mixture screws, the long part is that the mixture the engine is happiest with depends on a few things, so you just set it to where it idles the best. the factory idle mixture is about 12.2:1, with an exhaust on it you should be able to go a bit leaner.

for the float level, you look in the carb while its idling on a flat surface, if its dripping from the boosters the float level is too high, for a street car. ideally you want the floats as high as possible without it dripping at idle.

Starfox07 09-27-12 12:34 PM

I've uploaded a video, so you guys can see the problem[s] more clearly articulated.


Starfox07 09-27-12 04:44 PM

1 Attachment(s)
I designed a throttle cable bracket on cad today. I'm trying to get as close to stock mounting location as possible. This one will have provisions for the stock style throttle sheath bracket and also a throttle return spring at the bottom. It will bolt securely to two air-horn bolts on the fire-wall side air horn. I printed and cut out a paper template and everything works nicely, I just have to find a place to water-jet, laser-cut, or CNC my part :p

Attachment 697126

Siraniko 09-27-12 05:46 PM

How thick is it?

Starfox07 09-27-12 07:01 PM

2 Attachment(s)
It'll be .0625" steel, same as the factory bracket.

Here is a snap of the template mocked up. The final design has the throttle return spring mounting hole about an inch further over:

Attachment 697119

And a view of how I have my FPR mounted:
Attachment 697120

It's a bit angled, but I kind of like it that way. Plus I didn't have to drill a new hole in the firewall. :)

I'm finally happy to look at my engine! I never was with the EGI setup...all intake and no engine.

Starfox07 09-27-12 09:07 PM

Well if anybody has any ideas about my bouncing fuel pressure, let me know.


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