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-   -   Two Questions... (https://www.rx7club.com/race-car-tech-103/two-questions-477357/)

SCCAIT7 10-30-05 04:44 PM

Two Questions...
 
Well- I drove my car for the first time about two weeks ago at a hill climb in Alabama! WHAT A BLAST! This IS Racer Carol's old car... We found out through some research that it is indeed her old car! Whew! What an honor!


The carburator requires starting fluid to get the car started... At this time I do not have the extra CASH...to have the carb rebuilt.. Can somone give me an idea on how to make it start without fluid... PLEASE!


We are racing at Road Atlanta the second week in November... Does anyone have a sugestion on what rear-end ratio to run? Is there a way to tell what ratio is in the car without pulling the chunk out?

speedturn 10-31-05 12:20 PM

I'm the guy with the blue GT-2 RX-7 that finished 3rd overall at the Crow Mountain Hillclimb. http://www.crowmountainhillclimb.org/

You shouldn't need starting fluid to start your engine. Is the accelerator pump working on your carb? If you have the fuel pump on, and look down the throat of the carb, and turn the throttle, do you see two squirts of gas go down the throats? You seemed to be at the novice level on carbs when I met you. Maybe you should buy a complete, guaranteed setup carb from an expert. It can take a long time to learn all the little details about a carb like the Nikki, time that may be better spent doing other things (like working your day job.)


Can't tell what ratios are in your rear end with out pulling it. Old race cars usually have had those things swapped out many times. A 4.88 or 5.13 rear end would be nice for Road Atlanta. See ISC Racing's web site for their rear end prices. To pay them to install the gears in your rear end and freshen up the limited slip diff, it would probably cost around $1000 to $1200.

SCCAIT7 10-31-05 08:35 PM

Well hello! I have been around carburators since I was working on a Bugeye Sprite- I just have not had any experince with the RX-7 Carbs.

NasaPro7 10-31-05 10:29 PM

Shrug- I have yaw carb that has always required some gas to get it started. rather than crank it over, we pop the aricleaner and pour (spray) some gas down the carb. right upon turning it over, it fires right up. We do carry around a sray bottle of gas.
I avoided starting fluid for fear it would be too harsh on the apex seals.

Marcus

SCCAIT7 11-01-05 07:48 PM

Marcus- That is similar to what we have to do on the Bugeye with the SU's... We have to manually choke that one...just by simply cuping your hand over the horns of the carburator... Also- just this past weekend at the NASCAR race here in Atlanta- I saw a guy running down pit lane spraying gas in the intake...Anyway... I suppose if it is good enough for the NASCAR boys...It is good enough for me! Thankz!

speedturn 11-02-05 02:39 PM

SCCAIT7 - I too had SU carbs on a Datsun back in the '70s. They had no accelerator pump either, so they did not cold start very well.

I quit running the original Nikki 4 barrel carbs back around 1990, so I can't claim to know anything about the Nikki except that it is too small for racing. I then ran Solex-Mikuni side draft for 4 years, and then since 1994 I have been running the Weber IDA downdraft 2 barrel. Neither of these carbs have chokes, but they do have accelerator pumps. Instead of pouring gas down the carb to cold start, I just turn on the fuel pump and then pump the gas pedal a LOT, and then they start right up. They may not cold idle well, but they will cold start. That is why I was asking if you were sure that your accelerator pump was working.

SCCAIT7 11-02-05 09:25 PM

Speedturn- I would love to run a Webber- However I do not think that my compeditors would like me very much... the Nikki is not all that bad... well...yes it is! lol... Anyway... I am going to try to fire it up in the morning by hitting the pedal a few more times than normal! Maybe she will fire up cold...if not... hey...its a racecar...they all have their quirks!


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