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Hi Guys Im in need of wisdom and HELP!!, I'm located in Winston Salem NC , I don't know much about Rotaries but willing to learn. If there are some Rotor Heads that would like to come over to my house and help me tune this 12a I'll have a case of BEER waiting.... Im dying to take it out on the road!!!!!
The car will start on the 1st crank even when its snowing, after the electric choke goes off the car idles but is not smooth is jumpy, I did noticed that the rear rotor exhaust was glowing red I have a 1984 12a, Racing Beat Intake with Holley 600 (New), Racing beat full exhaust and MSD coils.
RB holleys are not that good for rotaries. Be better off with Weber IDA downdraft or even sidedraft carbs. Did it come with this setup or did you put it on there?
My guess is the header is glowing red because the rear rotor is running so rich its burning gas out the exhaust. I'm not real familiar with Holleys but a 600 cfm on an stock port 12A is too much carb, unless the engine is ported. Is it ported?
RB holleys are not that good for rotaries. Be better off with Weber IDA downdraft or even sidedraft carbs. Did it come with this setup or did you put it on there?
My guess is the header is glowing red because the rear rotor is running so rich its burning gas out the exhaust. I'm not real familiar with Holleys but a 600 cfm on an stock port 12A is too much carb, unless the engine is ported. Is it ported?
It came with a Nikki and it was clogged up, I had a Holley and a RB mani already so I put it on. I have seen 12a stock with 750 Holley's running good, my 12a is street ported. I still have the OEM nikki it will need a total rebuild.
If you take the time to modify the nikki it will be the best of all carburetors to use. I kind of doubt a 750 ran well on a stock port 12A but since yours is ported, then the holley might work with some tuning. Unfortunately I'm not Holley familiar. There are some folks on here that are. Hopefully they chime in with advice.
If you take the time to modify the nikki it will be the best of all carburetors to use. I kind of doubt a 750 ran well on a stock port 12A but since yours is ported, then the holley might work with some tuning. Unfortunately I'm not Holley familiar. There are some folks on here that are. Hopefully they chime in with advice.
When you say modify nikki what do you mean the nikki I have is from a 73
Originally Posted by Richard Miller
Devil in the details question. Is the Holley new from RacingBeat? Is it from a speed shop or other retailer?
High exhaust temperatures are caused by running lean. If your headers are cherry red like this, your rear rotor is going to be very lean. I would suggest not driving it until you get it sorted, since lean mixtures can lead to detonation.
I've heard that Holly carbs require special tuning to work properly on a rotary, so it may be that you will need to make significant changes to jetting and air bleeds for the carb you got to work properly.
When you say modify nikki what do you mean the nikki I have is from a 73
The Holley is NEW from Holley.com
If you didn't buy the holley from RB then you are going to have to reverse engineer the tuning they provide on their holleys to make it work with a rotary. As it sits that holley will not work well with a rotary.
You can take that nikki and do mods to it to flow enough fuel and air for a street ported 12A. There are a lot of threads on this. Jeff20B has done many and I did one as well.
I think its time to take a look at the mixture and the timing together. That header should not be getting that hot. Is you engine ported at all or are you cramming a ton of fuel down a stock port engine?
I think its time to take a look at the mixture and the timing together. That header should not be getting that hot. Is you engine ported at all or are you cramming a ton of fuel down a stock port engine?
Originally Posted by Medevack1
It came with a Nikki and it was clogged up, I had a Holley and a RB mani already so I put it on. I have seen 12a stock with 750 Holley's running good, my 12a is street ported. I still have the OEM nikki it will need a total rebuild.
yup, he said it was. I wouldn't think timing as much because if it was timing both rotors would be running lean would they not?
I agree with t-j, a Holly bought from racing beat has jet changes and many other things done to it to help it run on a rotary, coming straight from holly does not, and I bet all the problem is in the carb
Sideways but important point; if you're not running the stock Nikki you've had to have done something with the oil injection system... and unless you made provisions to direct it's output into the carb (as the RB modded Holley does) you'd best be pre-mixing 2-stroke oil into your fuel or you'll be short a motor pretty soon.
04-02-18, 12:45 PM
