I rebuilt a holley carb for a friend. Here is some knowledge of the carb kits. I got square bore and spread bore mixed up as you can see with my corrections. More detailed holley video to come
A nikki =465 cfm.thats from a rx2 carburator.i had one modified mechanical secondaries.dual distributor motor.rsce clutch Ltd slip accel coils racing points.adv.full exhaust.It made like.175 to 180 no porting.The early 12A were way better than rx7 engines.Except I wish I had put a electronic distributor.which it will fit.Cool projects.Ur having fun man
Hi Rad, I have a 12A Full Bridgeport in my 81 RX-7 and it had a 48 IDA on it which I have just removed and put a modified Nikki back on it as I was sick of all the bucking and jumping off throttle. The 4BBL is much better for cruising and driving around town. What Holley 4BBL would you recommend. Street car but only driven every other weekend. Want a bit more power and also the brap.
Is it worth changing carbs I have the 4b nikki on my 79 and for the life of me I cant get the stumbling out of the throttle under load I've been throwing parts at the car and these things only helped it almost seems like my secondary aren't opening right bc if I keep it under 3k theres no bucking same if I floor it but if I try to hold a idle at roughly 4k it will just sputter and die unless I give it more gas please help I've been dealing with this for 2 years I'm about to take it to Atkins rotary but that's pricey
Depends on the application. Street car, the holley is nice. Easy to start. Good drivability. Weber will take a lot more aggressive driving, no fuel slosh issues, but sacrifice low end drivability. Also can be hard to start in the freezing cold
Got my diesel-tech-of-a-girlfriend's car, far from home in Iowa down under in Florida with me. 83 GSL, with a 6 port 13b (believed to be) from 1986 swapped in it, holley 600cfm from Racing Beat. The carb had a stuck float, fixed that, I have major intermittent cut out like it isn't fully sparking, but the issue goes away at WOT. Well now it got worse and sounded like it dropped a rotor. The leading coil was burning hot (ordered a replacement), and I also noticed the trailing coil seemed to not be hooked up whatsoever. Fixed that and it ran better than ever (coil had cooled down by then). Got a ways away from work on my way back home and it's cutting out again and I have to go WOT to get it to go anywhere. Barely made it to my house. Aside from coil issues, what do you think it might be? Cap/rotor seem in good shape, plug wires are newer NGK wires, not really much else it can be?
Probabaly a carb issue. Stuck float again. Float set too high. Ie too much fuel in the bowls for cruising. And at WOT it drinks it enough to not overflow the bowls. That's where I'd start
RAD Potential I dunno. I had the carb off and I adjusted it with my boss who is a all american muscle “fuel injection is for pussies” kinda guy, and it was golden. Floats set good, jets clean, when the secondary engages it doesn’t chop the throttle.
@@stitch2k1 whats the fuel pressure at idle? Could be something in the distributor that is causing it to mess up at static timing, but firing properly when the internal advance is engaged.
@@RADPotential At this point I don't know, and don't have a way to tell. It won't idle whatsoever. I have to go WOT to get it to run, even after new coils. Going to get some help and test some things on it. Girlfriend isn't too happy her shitbox isn't running well but she lives in Iowa and I'm in Florida so she can't do much. Lol
So I tinkered with it last night and the car just decided to run fine, no issues. But it's getting cut out issues when the mechanical secondary on the throttle hits (by my guesstimation, I can't get to the secondary section and have it cut out without risking going past 8k rpm) but as before it's fine when at WOT. I'm thinking I need to soak the thing in carb cleaner for starters.
Hello RAD, I run a 12 a very slightly ported, and a 465 CFM Racing Beat that was on the car when I bought it. I often have a stumble at around 3000 rpm under load,. Idle is fine at 1100 rpm, Fuel pressure is set a 6.5 PSI, floats seem ok. Do you know what size power valve and what size jets should be in there? When I got the car, there was a plug instead of power valve, I put a 7.5 and I believe my jets are 49 but not sure anymore. What set up do you recommend: Power valve size, jet size and secondary spring color? This would be very helpful, at least I would have a base line to start from . Thank you !
I change the accel pump diaphragm recently and yes it seems to work normally. I got it from the Racing Beat “trick it “ kit so it should be the right one ( if I remember well it is the green polymère diaphragm). The hesitation is in passing 2800/ 3000 rpm. Does not do it in 2nd gear if I push harder, does it in 3rd gear every time. What RPM does it typically transition from idle circuit to main, and then power valve. And what RPM does it typically suck enough vacuum to start open the secondaries? I am a newbie at this so any education is welcome ! Thank you !
Did you have this hesitation before the PV install? 7.5 inhg seems about right for part throttle where it wouldn't be able to decide whether or not to open or close. The secondaries may be transitioning at that point. But generally they would come on above 4k. Does it feel like a lean stumble or a rich stumble. The pv could be opening too soon
@@RADPotential Yes i believe it did, but it s been a long time. That carb was never working great, and then I had the engine redone, so I am just only back at driving it. I will drive it this week end and try to be more precise in my diagnostic. I am not even able to tell you if it sound like a reach or lean stumble :) I will recontact you right after. Is here the best place to reach you?
