porkbun

2.5 Turns is the starting point for getting the proper mixture. How far down or up depends on the carbs and your car

If the manifold isnt homemade then it will fit under the hood with an 8x2 air cleaner. Ive run both SU's and 4bbls on my car and their performance is very close if not identical. 4bbl setups are worth more than SU setups if it has an 8007 390cfm on it or 465cfm

No actual dyno, All my results have been from my butt dyno. BSR works and works alright but the opening on the sides is probably around the same size as one of the 4bbl butterflies. An SU butterfly dwarfs it and one of those openings is feeding 3 cylinders. The AZC has wider openings and it is very apparent. The taller divider makes way more low down torque and I believe the wider openings are to blame for it pulling harder than the BSR from any spot (same carb setup). My Rankings: 1. Azc manifold 2. Adapter with divider 3. Tie: Cartech adapter 4. Bsr manifold EDIT: Currently running a set of Roundtops with SM needles and the all around performance is VERY close. Fuel economy acceleration seem about the same as the AZC manifold but again thats just a butt dyno and no concrete evidence. ITBs in the spring hopefully!

I just learned it from tinkering around with my car. When I got the car it had a stock 390cfm but was also advanced as far as the distributor would go. When I went back to stock timing I noticed that the car was running really lean/barely at all. Another thing I noticed was that if you do end up advancing the timing more, try mid grade and premium fuel. When I got the car it ran best on premium. Not Im at ~20 degrees and it starts and runs better on 89 midgrade. Holleys youtube videos are great and will give you a pretty good idea of how your carb works and how to troubleshoot

The problem with advancing the timing is that it requires a leaner mixture. If you have a perfectly good running car and just advance the timing it will run very rich. Retarding the timing will make it run lean. Timing adjustments will require jetting changes. First figure out where your timing is supposed to be depending on your vac advance then after thats all set you can start jetting your car.

The way I understand it (which could be completely wrong), total timing should be around 34 so initial timing depends on how much your vacuum and mechanical advance advance. Ive heard people with L28's run ~#54 jets which is 3 steps up from a stock 390cfm, my cammed l24 ran best with 55 jets. Checking your jets is as easy as pulling off the primary fuel bowl (which is only a hassle if you dont have the blue non stick gaskets). Idle should be the same and dont forget about the idle mixture screws when trying to change the idle. You can adjust when you want the choke to open and close by rotating the black electric choke cover clockwise or counterclockwise after loosening the three screws. The preferred pump cam among Z's is the orange pump cam. Kurbycars order of operations is correct

Are you using a regular 1850 or one of the holleys modified for blowthrough? I was pricing out the blowthroughs and it seems like my money would be better spent doing an L28et swap especially if the blowthrough carb goes for ~$700 by itself. Interesting idea but im not sure if anything will happen on this car

Bob Sharp Manifold was less than satisfactory. Great when daily driving but no oomph when flooring it. I think its pretty hard to cram 195cfm let alone 300cfm through this tiny opening Didnt even try to film any acceleration runs since they were so slow. So far the best manifold has been this one that was on the car when I bought it But Ive got something else which im excited to try. According to Dave at Arizona Z car: "The divider in plenum makes a dramatic improvement in low end response, I also opened up the runners for improved top end. Overall performance is excellent." and something found its way to my door today High divider: check Wider opening : check BSR Honestly I dont know why there are those stupid little ribs before the 3 and 4 cylinders. In my mind it makes sense that the biggest opening would be the best(which is why the original manifold I had was the fastest) but as you can probably tell by my idea a few posts up, im nowhere close to an induction expert. Had a 600cfm on the car for a few months and finally got my hands on a 465cfm which I think will be my final Holley. AZC is on the car and running but I havent really tested it yet. All thats left Holley wise is to get my hands on that original manifold then triples? 6 motorcycle carbs? Who knows !:stupid:

Im hoping this is the ticket! My temporary pipes right now are thrush glasspacks and theres not really any rasp at all so ill try my hands at a different brand and double them up. Ill figure it all out with some exhaust shops but I was just making sure there isnt some secret supply of tiny glasspacks with fins in them that I didnt know about

Hmmm. That does sound pretty similar and maybe if I double up those twice pipe glasspacks I can get that extra rasp. At higher rpms the sound was really harsh. Going to get my friend to upload another video

Yup I think its part 99996-E1045? I think the header is salvageable as its pretty thick and the pipes probably could be saved but I feel like that woud cost more than getting them replaced. This is the style I have on my car You seriously need earplugs with straight pipes! After a 1/2 hour drive my ears were ringing and im sure my neighbors loved it. Ill try and get the videos off of facebook(theyre not public) on here but the camera cant do it any justice since you didnt just hear it, you felt it going by

I didnt install it, im guessing it was installed back in the day at some dealership along with the Racer Brown cam aka "Slalom camshaft" in the comp. catalog. I know 2" is probably too big and true duals make less power but if its made it 43 years like this I dont really see a reason to change it (plus ive got power to spare :stupid:). I think the small outlet helps a bit but I think whats making that raspy noise is the interior of the glasspack. Ive still never seen anything like those fins inside. A big issue I noticed coming from the straight pipes is the resonance at about 2k and im not sure a homemade glasspack would help with that (or honestly how that works). I know a bunch of people probably think im crazy for wanting my car to sound like a bees nest but after a while you really start to like it. Magical fins?

Burping out of the carbs is usually timing and if your timing is set properly then that means you are too lean. I dont know how much the "2.5 turns" applies to you since youre running a 2.9L stroker but IIRC 2.5 turns was a baseline setting that should get your car started so you can tune it further. I wouldnt get so hung up on the # of turns but keep turning out until the car runs properly and make sure you have no vacuum leaks ( which can lean out your mixture)

Definitely going to hard to find if anyone anywhere still makes them but the sound was like nothing youve ever heard and sounds completely different than every other car on the road. 2" is the smallest I can find and they sound alright but theyre nothing special. Probably going have to learn how to weld so I can cut them up and get that sound back. Here are a couple more short vids. This one is with the complete exhaust (2 glasspacks, 2 resonator/glasspacks) And this is one with top glasspack broken off. You can hear how different it sounds at idle while the new glasspacks sound like the green 260Z

Im replacing/refurbishing my Datsun Competition exhaust and im not sure I can replicate the exhaust sound. Old exhaust is rusting apart so I think its time to save what I can and replace what I dont think is worth the effort. Heres what the complete exhaust looks like: Then this happened Top glasspack broke off! Not only was the glasspack a 2in inlet to a 1.5in outlet(already impossible to find) but the interior looks completely different than the modern glasspacks. Modern: Original https://lh6.googleusercontent.com/-QtZ2x3NiWQw/UYunJpST29I/AAAAAAAALFA/2gjvkhMrIBM/w903-h677-no/IMG_1640.JPG Is there any way for me to get the hornets back in my car?