Gimpdiggity

Hello everyone.

Please don't let this start an argument, I haven't been on this site in a long time because I have been so engrossed in getting my motorcycle running...

I have a 1986 base model N/A RX-7. I am thinking of going with that new Holley Carb setup on it.

My question is this: Is the thing just pretty much plug and play, or is there alot to installing it??

I mean, do you just install a higher flowing fuel pump, bolt the carb on, hook up the fuel line, hook up the throttle cable, and then go??

Or do you have to install other things so that the computer knows you have a carb now instead of fuel injectors??

What happens to the MAF sensors if you hook up a carb?? Do they just dangle there and not do anything or do you actually hook them up to the carb??



Please help me without flaming me...I did a search on this subject and couldn't really find what I was looking for.

Thanks,
Jeff

Aaron Cake

iTrader: (1)

It is not plug and play.

All the stock EFI components need to be removed, as well as the stock intake (upper and lower).

You will need to replace the pump with a low pressure unit designed for carbs, as well as the fuel filter.

The computer will never "know" you have a carb installed.

Then the whole thing will have to be tuned...Have fun with that....

Seems like a lot of effort to go through to make your car slower...

Gimpdiggity

Thank you for your post-whorish sarcasm.

Gimpdiggity

...by the way, I'm also not that interested in how insanely fast this car will be...I have a sportbike for blisteringly fast straight line and cornering speed...

I'm really just interested in doing something a bit different than all the other people around here do...

Aaron Cake

iTrader: (1)

What sarcasm? I answered your questions....

Uh, are you calling me a ricer?

Gimpdiggity

I understand that you answered SOME of my questions, but your sarcasm is quite readily evident...you didn't need to be a dick about it.


Why would I be calling you a ricer??

Evil Aviator

The Haltech E6K is now down to $1155 at the RX-7 Store. At this price, I cannot see any reason for a carburetor setup unless your particular racing rules do not allow aftermarket EFI. Everyone is different, but in my opinion, carburetors are more difficult to tune than fuel injection. Also, note that most aftermarket fuel injection systems also come with readouts and/or datalogging for air-fuel ratio, intake air temp, engine temp, MAP, and other parameters while a carburetor doesn't come with jack.

Carb conversion:
$850 Mazdatrix Weber 45DCOE Kit (works with stock lower intake)
$110 Holley Blue fuel pump & regulator

FYI, the stock AFM sucks. The best thing about the EMS and carb conversions is that they both let you throw the AFM in the trash where it belongs.

You could install an "air pump supercharger".

BTW, you may not want to make a point of insulting those who help you out, as they will not be prone to help you in the future if you continue this. If you don't really want to know the answers or opinions on a subject, then don't post a question. Aaron was right about everything except for the lower intake manifold, which DOES need to be replaced if other types of carb kits are used.

Aaron Cake

iTrader: (1)

Sorry, I thought I answered them all.

To be more specific.

The MAF and other sensors related to the fuel injection will have to be removed. The stock ECU can be fooled to still run the igniton, but I don't know anything about that so you will have to ask someone else. Most people install a distributer at this point.

There is a lot to installing it, and it is actually a downgrade. That is the point I was trying to get accross.

Gimpdiggity

Thank you for your answers Aviator...and I wasn't insulting Aaron, I was just pointing out that he seemd a bit snide in his response.

Gimpdiggity

That was the main concern that I had. I read that it needed the different fuel pump, but I was really confused as to where the MAF sensors and other sensors like that would go...because I thought if they weren't showing a reading to the ECU that it wouldn't let the car run correctly...

I would probably be better off just porting the intakes and getting a better ECU though, huh??? I really don't want to have to get a laptop to run it though...

Gimpdiggity

If I wanted to go lots cheaper, would an S-AFC and a ported intake help generate more power??

I'm somewhat confused on what exactly the S-AFC does...

Taranis

What kind of modifications does the car already have?

The S-AFC helps you tune the a/f ratio of the car for different power levels depending on your driving style and/or condition (racing vs. highway cruising). I'm sure you knew that already, tho.

If you haven't upgraded the intake and exhaust, and performed the throttleboddy modification, I'd probably do that first, second would be suspension and brake upgrades before the pricey stuff such as a fuel controller and ported intake.

For the money, n/a is still n/a, and you're going to hit a brick wall at @ 200 hp without some kind of forced induction, or N20..

JB

Gimpdiggity

Would I even need any kind of fuel controller for just a mild porting of the intake?? Or would the stock computer be perfectly able to handle just a mild porting of the intake, the throttle body mod, and a cone intake...

Taranis

The stock ecu and afm would work fine with the cone filter, TB mod and mild porting... no problem at all.

Do the intake and exhaust at the same time if you can. More air isn't much good with restrictive stock exhaust.

JB

Gimpdiggity

I came to the realization a while back that this car just isn't going to be really "fast" as in going in a straight line, so I kinda just let it sit and bought my bike instead...

Now I've been looking at it again, and I've decided that the thing needs to be reworked and at the very least made look nice again...

I'll probably just end up doing basic bolt-ons and doing the body work...then I'll go suspension and stuff...

Maybe the whole carb thing will just have to wait...


Or maybe I'll just be real odd and go buy that turbo Chevy Sprint that's for sale by my house...heh...

Aaron Cake

iTrader: (1)

If you are looking for more power and already have the "basic" mods (Intake, exhaust, etc) then an S-AFC will certainly help. It will allow you to fine tune your fuel delivery without all the expense of going to an aftermarket ECU...I believe there is a topic slightly lower than this that covers what exactly the S-AFC does.

Gimpdiggity

Yah, I JUST found that one that explains what it does Aaron...you're talking about the one where it tells how it fools the ECU into thinking that more or less air is present, right???




Well, I think that's what I'll do then...I'll just go for a mild porting on the intake manifold (I'll use the How-To that I just found in here) and then I'll get myself an S-AFC sometime this fall...

Taranis

*deleted*

JB

HAILERS

GIMPDIGGITY....Here's a thread from the first of the year that has a lot of replies to it: https://www.rx7club.com/forum/showth...ghlight=holley

chaos7

iTrader: (2)

I have the weber sidedraft setup, but it should be similar. I used the fb fuel pump, had to get injector plugs and blockoff plates for a couple holes (theres one on the top of the block), and paper-clipped a connection where my afm usually is. it works great, although i need to retune it (summer temperatures). The stock ignitioj should work fine with it, ive had no problems. you do need to get some extra fuel line though (the piece in front needs to be extended a little bit)

gray

FPrep2ndGenRX7

If you really want to do something different then get a Haltech. I can't think of anybody that has one on an N/A.

Evil Aviator

Hmm, I don't know of anybody, either. However, a friend of mine has a Wolf3D 3.0 on his 87 Sport with a stock engine block. He has yet to lose a race to a stock-turbo TII. However, stock-turbo FD's wax him, so there is a limit to what an EMS can do for an NA.

Snufelupogus

iTrader: (2)

If you really want to do this (which I dont see why not, mine will be carbed as soon as I can), PM guru.
Yesterday we carbed a streetport 13B in a GSL-SE. We had to change the fuel pump and fuel filter from the GSL-SE (fuel injected one) to the one from a base FB. An aluminum adaptor plate was made to use the 12A carb on the 13B. A distrubtor was put in, carb was bolted up, and I think there are like 3 wires, or something silly like that, going to the engine.
Like I said, PM guru, he'll be able to help you out.
Personally, I dont see why someone would pay 3-4x the amount of a carb setup to go with a stand alone setup and get the same horsepower

NZConvertible

I've hardly call a 12A carb an upgrade...