SU will perform better than webers. Webers work, nothing wrong with using them. If you want a different look than the camaros you could go fo solex mikuni. Thought about multiple throttle bodies. One of the skylines had 6 ITBs.
Are triple webers more than just cool looking?
I am in the process of determining what to do to rebuild or replace my 42/47 dual downdraft weber motor. I am looking at a motor for sale, with a reported low miles on it with triple DCOE carbs. I must say that the set up looks really cool. Does this set up make a significant performance difference on an otherwise stock motor?
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To get the performance out of the triples you will need more head work done. A 390 Holley correctly will work better than many triple set-ups.
If your interested in staying with a stock engine, a good tune-up (w/valve adjustment), Pertonix/MSD combo, a header and a 2 1/2 exhaust will work just fine.
If your interested in staying with a stock engine, a good tune-up (w/valve adjustment), Pertonix/MSD combo, a header and a 2 1/2 exhaust will work just fine.
SU will not perform better than the Webers. I would suggest you use either the twin SU setup (By far the most British-looking setup, and very easy to work with) or go ahead and use the Weber triples if you wanna get a huge wow factor when you open the hood. Holleys and Weber downdrafts just don't look right...
You will need to do headwork to fully realize the potential of triples. And you have to switch jets out in order to tune them, which makes for a tedious and pricey process. They will make a difference on a stock motor but not an overwhelming one. In the end, I would recommend you go with triples if you have future plans for mucho power, and SU's or your Weber downdrafts if you are happy with a 180hp performance ceiling. Note that you won't have much trouble selling the triple weber setup for a good chunk of change if you decide to trade for SU's.
You will need to do headwork to fully realize the potential of triples. And you have to switch jets out in order to tune them, which makes for a tedious and pricey process. They will make a difference on a stock motor but not an overwhelming one. In the end, I would recommend you go with triples if you have future plans for mucho power, and SU's or your Weber downdrafts if you are happy with a 180hp performance ceiling. Note that you won't have much trouble selling the triple weber setup for a good chunk of change if you decide to trade for SU's.
Highly second the ghost. Putting webers on a stock 82' l28, it did have a header and 2.5' exhaust - I went from 138whp to 159whp. Then I added a cam and went to 171. Then I had the entire motor built, lots of head work, 20 over, larger cam, forged pistons making a 12:1 compression motor. Now I put down 258whp.
Downdrafts of any sort are not for performance. The SU's will outperform them, and really the SU's will be plenty until you really build it. Norm (the 12sec SU dude) runs high 12's with SU's (slightly modded) on a motor he built in his garage. Details details.
Your car would look great with the triples. There is a lot of support on tuning them I can help you if you'd like. Plus the triples go for anywhere between $500 and $1200. You can get a nice set of SU's for a couple hundred.
The choice that is better than the webers or mikuni's is the ITB EFI. Still looks great, but you have to be ready to get back into the electronics. Read some of the post by Tony D, he explains picking up around 40 hp by going from the webers to ITB injection. Given this is on a prepped to i don't know what level race engine, but still that is big in a 2500 lb car.
Downdrafts of any sort are not for performance. The SU's will outperform them, and really the SU's will be plenty until you really build it. Norm (the 12sec SU dude) runs high 12's with SU's (slightly modded) on a motor he built in his garage. Details details.
Your car would look great with the triples. There is a lot of support on tuning them I can help you if you'd like. Plus the triples go for anywhere between $500 and $1200. You can get a nice set of SU's for a couple hundred.
The choice that is better than the webers or mikuni's is the ITB EFI. Still looks great, but you have to be ready to get back into the electronics. Read some of the post by Tony D, he explains picking up around 40 hp by going from the webers to ITB injection. Given this is on a prepped to i don't know what level race engine, but still that is big in a 2500 lb car.
I'd like to see the numbers from a 280zx with header, 2.5 exhaust and su swap.
Keep in mind that the 20 hp bump matt saw when he went from a stock fuel-injected l-28 is attributable mostly to the removal of the horrible intake manifold on EFI cars. The carburetor manifolds on l-series motors flow much better than the EFI manifolds. If he had switched SU's out for triples his results would have been far less dramatic....except for the WOW factor, and the sound, and the happy jump that well-adjusted accelerator pumps on triples give you. I have a friend who autocrosses a 240 with an l-28 with a shaved p-79 head and a stage 2 cam and headers, and he actually prefers the SU carbs (with SM needles) over triples because the throttle response is smoother, even though he clearly is giving up a few horsepower.
Norm's 12-second SU's were not slightly modified; they were HIGHLY modified....bored out and given new throttle plates, and equipped with air horns and no air cleaner. Not a good street setup. Drag racing setups usually aren't!
Norm's 12-second SU's were not slightly modified; they were HIGHLY modified....bored out and given new throttle plates, and equipped with air horns and no air cleaner. Not a good street setup. Drag racing setups usually aren't!
Have to disagree with Ghosttanker on this last post. The stock SU to Triples was good by Mikuini's Dyno Testing to be worth around 22% more HP. The EFI, slightly less, only about 15% bump mainly due to the L28 not revving as high as the L24 due to chamshaft, and the fact that the EFI was FAR more efficient than the SU's in making REAL horsepower (not just a peak number.)
Norm's Modified SU's ran around just fine on the street. I don't know where he gets his 'facts' surrounding Norm's mods, but I guess if you consider the yellow plastic donuts from a kid's stacking toy cut in half and stuffed into your individual air cleaners as 'air horns' then I guess it's a somewhat accurate description of Norm's Setup...other than that 'no air cleaners' part... and some other stuff...
Triples are a fine daily driver addition, if you have Mikuinis. Webers notsomuch. The Mikuinis were an OEM fittment and drive like an OEM carb with good drivability. Webers are more towards the 'all or nothing' range of setup and I've never been able to replicate the power AND gas mileage out of Webers that I got out of comparably-equipped Mikuinis. They will make the power, I have never seen Webers come close to the economy Mikuinis deliver at the same power levels.
If nothing else, put a REALLY REALLY REALLY good muffler on that car, cork it up silent. The sound the Webers or Mikuinis will make when you floorboard it will more than reward you for your efforts. They are a performance adder. Some of the comments to this thread are, well...ZCar.com expected I guess...
Norm's Modified SU's ran around just fine on the street. I don't know where he gets his 'facts' surrounding Norm's mods, but I guess if you consider the yellow plastic donuts from a kid's stacking toy cut in half and stuffed into your individual air cleaners as 'air horns' then I guess it's a somewhat accurate description of Norm's Setup...other than that 'no air cleaners' part... and some other stuff...
Triples are a fine daily driver addition, if you have Mikuinis. Webers notsomuch. The Mikuinis were an OEM fittment and drive like an OEM carb with good drivability. Webers are more towards the 'all or nothing' range of setup and I've never been able to replicate the power AND gas mileage out of Webers that I got out of comparably-equipped Mikuinis. They will make the power, I have never seen Webers come close to the economy Mikuinis deliver at the same power levels.
If nothing else, put a REALLY REALLY REALLY good muffler on that car, cork it up silent. The sound the Webers or Mikuinis will make when you floorboard it will more than reward you for your efforts. They are a performance adder. Some of the comments to this thread are, well...ZCar.com expected I guess...
My only experience with moving straight from SU's to triples was on a 2.4 liter motor going to triple Webers, and, like I said, the improvement wasn't that dramatic. My experience with going from EFI to triples was very dramatic. Sorry I don't have dyno sheets. I've never run Mikunis or Solexes and I have very little experience with Dellortos, mainly because I have always had real difficulty getting jets for tuning anything but Webers.
My "facts" regarding Norm's build are from memory....it's been years since I read his posts regarding his mods to them, but I'm pretty sure he bored them out, and ran without air cleaners on the strip...if you want to drive on the street without air cleaners that's your business, I guess, but personally I don't feel it's a good street setup.
As for the accuracy of Mikuni's dyno testing, it might be right, or it might best be filed in with the 15% more HP claims from K&N regarding their cold air systems... there's a lot of puffing and fluffing out there. Like I said, I've never run Mikuni's, but I have run Webers on a Canon manifold, and while the difference over SU's was noticeable, it was certainly not a 22% bump.The OP did specify he was thinking about a Weber setup, not Mikunis.
My "facts" regarding Norm's build are from memory....it's been years since I read his posts regarding his mods to them, but I'm pretty sure he bored them out, and ran without air cleaners on the strip...if you want to drive on the street without air cleaners that's your business, I guess, but personally I don't feel it's a good street setup.
As for the accuracy of Mikuni's dyno testing, it might be right, or it might best be filed in with the 15% more HP claims from K&N regarding their cold air systems... there's a lot of puffing and fluffing out there. Like I said, I've never run Mikuni's, but I have run Webers on a Canon manifold, and while the difference over SU's was noticeable, it was certainly not a 22% bump.The OP did specify he was thinking about a Weber setup, not Mikunis.
theghosttanker said:Keep in mind that the 20 hp bump matt saw when he went from a stock fuel-injected l-28 is attributable mostly to the removal of the horrible intake manifold on EFI cars. The carburetor manifolds on l-series motors flow much better than the EFI manifolds. If he had switched SU's out for triples his results would have been far less dramatic....except for the WOW factor, and the sound, and the happy jump that well-adjusted accelerator pumps on triples give you. I have a friend who autocrosses a 240 with an l-28 with a shaved p-79 head and a stage 2 cam and headers, and he actually prefers the SU carbs (with SM needles) over triples because the throttle response is smoother, even though he clearly is giving up a few horsepower.
Norm's 12-second SU's were not slightly modified; they were HIGHLY modified....bored out and given new throttle plates, and equipped with air horns and no air cleaner. Not a good street setup. Drag racing setups usually aren't!
Norm also ran a 2.9 litre set up with the bored out SU's to accomplish his 12's. You have to search HybridZ for his posts under the alias he used there before being banned from the board (different then his moniker here). If memory serves me it was a stroker crank, 240Z rods & shaved turbo pistons in a l28 or something to that effect. Its been about year since I came across the post.
I'm leanin,' toward Tony at this point. I ran Mikuni 44's on the GT-2 car. Flat out LOVED them for tune-ability. They even had an externally adjustable float level! We're now stuck with Webers which I've been running on the street for 10 yrs. Triples give throttle response and control similar to a 4 cyl. four carb motorcycle. I've wadded this set-up on 7 different motors and jet to each motor with my supply of jets. Good news for someone that doesn't even own a laptop. Buy the 1979-80 vintage Haynes Weber Carburetors book. It lists jets for baseline for every car on the planet, the multiple carb upgrade kit p/n's and the baseline jets for them, as well. I think the round tops are like on/off control and are difficult to adapt to different motors. The down drafts would be passable ONLY if the linkage assy is rigid and is adjusted to ensure the secondaries go WOT when the pedal is down. If you like the triples, I will gladly help you tune them via PM.
Nick
PS- I've got a GRUNCH of Mikuni jets if any one is looking!
Nick
PS- I've got a GRUNCH of Mikuni jets if any one is looking!
I'm interested in those Mikunis jets if they haven't been messed with...
Panic ensues!! I archived them and haven't found them yet. Sleep will be lost. "Messed with"!!! Preposterous blasphemy!! Kept in a large, labeled snap lid box. Drilling was never even entertained.
Nick
Nick
FOUND the Mikuni Jets!!! PM sent to GNOSEZ
Nick
Nick
Gee,i'm putting 410 to the ground with a horrible factory FI manifold.I'd better change it.
Arubabill said:Gee,i'm putting 410 to the ground with a horrible factory FI manifold.I'd better change it.
Lets keep this topic in the realm of N/A Nissan L series engines.
How about keeping it realistic?If the manifold won't support the "number",then the motor can't make the number.The fact that i have a turbo is completely IRRELEVANT to the quality of the manifold.
They will definitely increase your knowledge of gas station locations. On a trip from C. Fla. to Atlanta, my triples used 1/3 more fuel than my friends SU-carbed '72.
That sounds about right.Tell us,who got to Atlanta FIRST?george71z said:They will definitely increase your knowledge of gas station locations. On a trip from C. Fla. to Atlanta, my triples used 1/3 more fuel than my friends SU-carbed '72.
Triples That aren't jetted right or are not synchronized together, will give such results. (George71z). Properly jetted and synched, The car should drive like a motorcycle!
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