Inspector71

I found several gen 1 cars, mostly 12As that were in like new condition selling in the 4 to 6K range, not bad, but snapped up on the spot. Wow. I also found several gen 1s going for outrageous prices like $16K for an 80' Rx7. It seems most of them were that amber/bronze/gold color or else I'm seeing the same one over and over. I had an 80 G model that was the same color. Should have kept it.

peejay

Kinda this. I've been on the fence for a while. I have this car that is not a POS that would not be laughed at as a tradein, and I keep thinking of buying something used in the $10-15k range. Evos aren't there yet, but Focus STs are. So are DSG-equipped GTIs and Mazdaspeed6s and Cruze Ecos (don't laugh, they were the lightest Cruze with the coolest engine) and it always comes back to: None of them drive as nice as my Volvo. Which is sad because I feel it's a tradeable car because I don't think it drives as nice as my 29 year old Volkswagen.

So I'll keep the Volvo, maybe do a reflash to bring the little turbo four up to 200hp spec, or maybe not because really it's plenty good enough as it is. The super funny thing is, it's a Mitsubishi chassis, and it uses the same Lucas calipers that two of my VWs do. My 3100lb 170hp sedan has the same brakes as a 15 year older 2500lb 130hp Jetta. (And my ????lb 90hp Quantum) But everything that attaches to the chassis is JIS bolts (12/14/17/etc) while the bits that are part of of the subassemblies are DIN bolts (13/15/18/etc). Banjo bolt was 14mm (chassis: Mitsu), caliper bracket bolts were 14mm (chassis: Mitsu), capiler slide bolts were 13mm (subassembly: Lucas).

In that respect it's like English. Everything comes from somewhere else and brings its eccentricities with it. Once you know the history of the word (or the car part) then it will make sense. If you don't know, then you're floundering in the dark wondering what idiot came up with this idea.

j9fd3s

iTrader: (3)

we ran the side show for the WTCC race a couple of years ago, and the cruze kicked ***. its really odd when you consider its a european race series, the US car was by far dominate, and i can't say that i had ever seen one, even though its an american car, and this was america*

the JIS, vs euro vs Whitworth vs standard is interesting. my Tr3 was 90% standard, so my tools worked on it. this MGB is odd, its partly standard, but partly whitworth (and presumably there is some metric in there in 1980), the really odd part, the philips screws are a different bit.

ray green

iTrader: (14)

You guys are getting abstract.

The SA's and FB's are so damn expensive because they are seriously fine cars.

j9fd3s

iTrader: (3)

they are actually quite cheap. for instance the only car i've driven that is better than an SA, is a Triumph Tr3, and those are over 10k for a decent one, concours cars are mid 20's.

a miata is a good runner up, and those are $3-5k, and up.

everything else lacks the simplicity, practicality, and FUN of the SA/FB

Jeff20B

iTrader: (13)

They used Reed and Prince! A phillips will work, but be careful not to do any damage.


Edit: Actually maybe they used pozi drive phillips (bottom row).

Jeff20B

iTrader: (13)

This is interesting. Looks like there is such a thing as a J-spec screwdriver. No joke! Because there are such things as JIS-spec screws [Japanese Industrial Standard]. Maybe that's why I've seen so many stripped phillips screws on so many distributers? We've been using the wrong screwdrivers the whole time?
Kawasaki KLR 650 Forum - View Single Post - In Chile and top subframe bolts broke

j9fd3s

iTrader: (3)

lol, possible. maybe thats why the carb screws are such a PITA!

Jeff20B

iTrader: (13)

I've just gone with a slotted screwdriver first to break the dual style screws loose, then spin them out with a US-spec phillips. It prevents damage on carb screws and dizzy screws.

ray green

iTrader: (14)

I stripped enough of those carb screw threads to learn that it's best to take a pair of small vice grips to bite the outside of the screw and give it a pop to break it loose.

And J9 is correct, SAs and FBs aren't that expensive.

Look what you can buy up the road from me in Greenville for only $4500. A 1980 LS, all original, 38,000 miles:

http://greenville.craigslist.org/cto/4874847944.html

peejay

And Spec7/Pro7 ate up all the solid/cheap ones. This is just like how it is extremely hard to find an NA Miata that isn't a ragged POS, all the good ones were turned into race cars (and then totaled because Spec Pinata)

peejay

This is 100% the truth. If you have the CORRECT screwdriver bits, and are careful to ensure that they fully engage the screw, you will not strip the screw head.

You'll break the head off, but at least you won't strip it

In other news, the top of a Nikki can be held down entirely with the air cleaner mounting stud and the gasket won't leak.

j9fd3s

iTrader: (3)

the Pro7 cars actually seem to have retired, so i've passed on buying a huge number of them, they are just sitting around in garages. point of fact Mr Peepers is a pro7 car that hadn't been run in forever and it was just sitting in my friends rafters..

DreamInRotary

iTrader: (49)

Curious as to how you found that out...

j9fd3s

iTrader: (3)

jeff told him!

Jeff20B

iTrader: (13)

Or Sterling did.

t_g_farrell

iTrader: (1)

You discover it the first time you go to take the top off while its on the car and it
won't come off even though you have removed all the screws. Ask me how I know.

peejay

Broke all the screws off in the carb body, as implied by the first part of the post.

Also, only using the air cleaner stud made getting the top off MUCH faster. Never did figure out how to get the floats right. The only luck I've had with floats is by not screwing with them.

Jeff20B

iTrader: (13)

I think I taught myself how to set floats. I also had to figure it out on a set of Grose jets. Basically the same, but they were way off causing a very overfilled float bowl set that way by the previous owner. I don't know what that was about. But yes I leave them alone every time I can. I think Sterling drilled that part into our heads back in the day.

peejay

I'd take anything Sterling said with a huge grain of salt. I never did agree with his apparent tuning philosophy of "make the carb completely useless on tip-in and try to cover it up with a MASSIVE accelerator pump shot". All this does is kill fuel economy and make the carb undrivable. I haven't seen a Sterling that was able to do anything useful other than idle.

IMO the accelerator pump itself is a band-aid for poor fuel metering. The better the carb is, the less accelerator pump you need. I've driven some wickedly good carbs, razor sharp throttle response, and this was NOT gained through accelerator pump...

Jeff20B

iTrader: (13)

That's interesting, peejay. I know you've tested a couple of Sterlings before, and they had some kind of problem. You had to swap some parts around just to get one of them to work, or something, right? In the end, the customer didn't feel like he got his money's worth, if that is correct.

Granted I've never driven a Sterling before, and now it looks like I won't ever get to, but I think I did pretty well for myself modding my own. I did briefly drive a Yaw around a parking lot once. It was decent, but I bet my carbs have better driveability.

You bring up some other important points that I've been meaning to discuss on the forum for a little while now. So here goes...

My hogged out Nikki has much bigger venturis at 24.9mm (or .98" as RB recommends) which work better in my opinion than Sterling would have been comfortable with as his were always 22mm, which he insisted on based on his and Carl's findings. With that said, I find my carb's tip-in is a little lacking compared with a Hitachi or an Edelbrock or any other big carb, but certainly driveable and fun! And it isn't a problem; the low end torque is phenomenal compared to any stock Nikki. So judging by venturi size alone, I totally disagree with Sterling as well and decided to go my own way with these carbs. Glad I did.

My accel pump nozzles were drilled with a size smaller than Sterling's recommendation. Mine are .045" to. 046" (or 1.18mm or the "118 drill bit" I always talk about). Sterling said he does his to .050". Now THAT sounds WAY TOO BIG! Especially for a stock ported 12A! I can see what you were talking about regarding accel pump mods. Totally not a good idea and will wreck gas mileage, well, exactly like you said. I think mine are a little too big as well, but I didn't have a smaller drill bit handy lol. Plus being a bigger engine with more porting and a turbo, 118 is really not that bad actually. It might be just about right.

It's as if Sterling was living in a bubble where his own personal car with a stock ported 12A and the RB long primary was the only thing that mattered, yet he claimed his carbs would work on a ported 13B thanks to its ultra tuneability, and would work great on a full bridge! Um really? I can see a stock to mildly ported 13B working, as a 74 spec 13B from a rotary truck had a factory hitachi with 22mm venturis, but a bridgeport? He also claimed it would work or wanted to try one of his carbs on a supercharger of some sort. Obviously that never happened. I think he bought an Eaton but never got it up and running. He should have gotten a Camden during its heyday because those at least bolt onto a rotary. I think he even talked about twin charging for a while. Can that even work on a rotary? Forget the supercharger. Just go turbo, dude, and take advantage of the rotary's powerful exhaust! Of course I don't have to tell you that; I know you like NA rotaries best. You think turbos are for trucks.

Sterling didn't have a ported 13B to play with, and it shows in all of his writings and personal tuning philosophy; practically proclaiming that only HE and Carl, with their extensive flow bench tests to keep maximum velocity at all costs so the 12A wouldn't want for driveability (aka velocity) at really low RPMs, was the ONLY game in town. This is after Yaw stopped making these, of course. Then that cobra guy stepped in briefly, and stepped back out. Not sure what became of him. The point is they stuck with a smaller venturi size for some reason, which I think was dictated by the flow bench only, and not so much in the real world. I gotta say I don't trust theoretical stuff like that very much.

I think in one of my recent carb threads, Carl claimed that once you go beyond the "perfect" textbook venturi shape, NO amount of air bleed and jet tuning would "correct" the air fuel curve. Nice way to discourage development, no? Maybe protect the bottom line a little, or at least try to? They've both been known to do that, and there's nothing wrong with it, usually, unless it stifles creativity for us and you still end up with less development. In the end was it worth it if they're not doing carbs anymore?

I have anecdotal proof that what Carl said should be taken with a grain of salt as well. It's nothing personal but some things need to be said.

I'm talking about an actual GT1 race car carb I got on a waterlogged pineapple racing engine back in 2005 or so. It was modified by a guy named Dave *******. He wrote the carb's specs on a couple of business cards which I photographed and posted on the forum (I could dig up later). He bored the primary venturis out to 26mm and the secondaries out to 31mm. He didn't do any Yaw or Sterling mods to the booster arms or the Sterling accel pump mod. The jets and air bleeds were set up to be huge which would make them very rich but over a very limited RPM range (probably for really high RPM as the engine had carbon apex seals). I tested this carb on one of my 4 port 13Bs ported to 74 spec, and with the tuning as-is, it didn't even want to run for me. So I investigated and swapped out the too-big air bleeds for some stock SA ones but left the fuel jets alone. Viola! It worked. Or rather it was at least driveable (and had more low RPM grunt than ANY Nikki I had ever driven before!). It still wasn't tuned for the street as it was still overly rich but an NA can tolerate a little over-richness. Dave had 155 primary jets and 235 secondaries. Yep, a bit too big. Turns out he drilled a set of 170s you can see in the picture I posted in the same thread with the other pics of the racing Nikki. Since then I've swapped in some more appropriate fuel jets and have yet to test drive it in its intended vehicle.

So if Carl were correct, what about the racing Nikki with its 26mm venturis and insane low end torque? Doesn't that totally undermine everything he and Sterling ever said about this subject? What about the other MFR 465 Nikkis from back in the day? I understand you can only come close to the "perfect" venturi shape if you leave a little meat in there. Once you go beyond about maybe 23mm, the shape is less like a venturi and more like a funnel that just sort of lets the air in as fast as possible with maybe some loss in velocity down super low but would never be noticed in the real world because it is at a rate that is under where a 13B would idle. Now a stockported 12A is going to have less flow at the same idle RPM so I can see some of his concern, but in the real world has it ever really been a problem? I honestly couldn't say as I've done most of my testing on 13Bs. Remember Carl and Sterling didn't have a grasp on turbo tuning, which I'll get to in a moment, so it stands to reason that perhaps most of their knowledge was gleaned from the flow bench and less from real world sources.

The extremely hogged racing Nikki still seemed to do ok at low RPM with a rock solid idle. And even with a stock accel pump, it only had a minor off-idle glitch caused by a damaged base plate, which I've since swapped out for a healthy one. Then I only did the Sterling accel pump mod to get rid of the secondary bog, which it did. It also got the trimmed booster supports with aerofoil shape. I have yet to test all this with the swapped base plate but I'll try it later this year when I do some much needed NA tuning on some carbs around here.

I honestly don't recall whether any of them (Carl, Sterling etc) had a wideband in any of their cars, but I installed one in my RB long primary, just in one of the runners, which turned out to be good enough for some basic NA test and tune, and I can tell you the air fuel curve was just fine after a basic jet and air bleed swap. This is where I learned that an NA tune wants slightly bigger fuel jets than a turbo tune. In fact it was so good the car almost wanted to break them loose in gear on dry road which it's never been able to do before I started messing with Nikkis. No Hitachi, Weber or Holley/Edelbrock ever did that. I'm still talking NA here. I even had an NA 20B in this car for a bit, and it couldn't do that. Granted it wasn't tuned, but the point is the basic 74 ported R5 13B with just a hogged Nikki that I built, did it all, and it didn't cost a lot of money or time spent waiting for Sterling to deliver. I guess some folks are still waiting? He always wanted to sell me a carb. Looking for approval from someone he apparently respected on the forum? He granted me mod status on his backyard mechanics forum, so maybe.

I love the concept of a hogged Nikki. No fuel slosh issues like a Holley or Edelbrock turned sideways, no expensive parts like a weber, actual secondaries that work amazingly well with no bog, perfect or darn close air fuel curves that are tuneable (as close as a carb can get), pretty easy cold starts with no choke the same as a Sterling, and you can add boost!

Speaking of boost, Sterling and Carl once tried to do a boost prepped Nikki and sent it out to some kid on the forum for testing. I say kid because he didn't act like an adult — he acted pretty incompetent, actually. Probably not the best choice for their first venture into Robert at RS' territory (not that I'm promoting him either). The kid didn't even have a wideband if I recall? Scary!

It was chronicled in a big thread dating back about ten years ago. I found it recently and had to stop myself from yelling at the computer monitor just from the frustration of not being able to help those poor bastards. It's too bad I didn't know very much about Nikkis back then. I'm sure I could have helped.

I spent the better part of last year educating myself about the boosted Nikki and ended up with a very pleasant and very powerful driveable carb in vacuum and boost. No bogs at all, which apparently is the most difficult thing to get rid of on a boosted Nikki; the secondary bog or "hiccup" as Robert's customers call it (no doubt trying to minimize how annoying the bog really is, which is really more of a 1 to 2 second delay while you wait for the secondary circuit to start flowing in boost, and all four of my carbs did it).

I solved the bog! It took a while, but it's totally gone now. All of my tuning discoveries are on the forum. I don't hold any secrets back because I don't really see a point. We're in the future now! We have the interwebs. Let's use them! I'm not building these things to sell. In fact I'd like to see more people on the forum modify their nikkis for boost because I don't like webers for some reason. Well I don't agree with the concept of a boosted 2bbl carb on a rotary, so it makes sense to recommend against them and put it all out there for others to benefit. If someone disagrees, they can go with a weber or EFI. lol

The journey wasn't all candy canes and unicorns. At one point the secondary bog was so annoying I got sick of turbos and pulled the setup to go back to NA. This lasted for about a week. Once you go boost, you don't go back! In the time off, I got a few ideas from the internet and even from this forum for how to deal with the secondary bog. I tried them and it got rid of almost all of the bog! Took it down to like no longer than a half second or less. And the fix was so simple! Just solder filled secondary slow air bleeds #1 and #2. Remember these are there to "shape" how/when the vacuum secondaries open. With mechanical secondaries, they are no longer needed and can be blocked off. The final bit that got rid of the rest of the bog was making the secondary main air bleeds just a bit smaller. This time a little Sterling or Yaw info came into play here. You just machine the secondary main air bleeds to accept some holley air bleeds or even some stock Nikki jets. I once again used my trusty .045" or 118 drill bit for the new size and drilled a set of stock 92s to 118 and threw them in. The turbo became almost too powerful and would break them loose in 3rd gear, dry road, up a hill. I couldn't look at the wideband because the car likes to go sideways, but it felt healthy & sounded good so I'm sure the af mixtures were fine if not still a little rich yet. Like 10.0 on the AEM with the UEGO sensor. A little more tuning is needed, but I'm practically there!

Oh and if you're wondering, I had to reduce the secondary fuel jets from a stock 160 down to 150 because with less calibrated air coming in, I had to reduce the fuel. Seems to work great in boost which is the opposite philosophy of just about everyone accept for Robert who discovered a boost tune wants smaller/leaner fuel jets than an NA tune, and one of his customers posted it buried deep away in a post from about ten years ago. I found it. Actually, I discovered this little turbo tuning tidbit for myself independently before ever seeing it on the forum. Strange that he and I agree on something, but it's not really that strange when all you're looking for is results and don't need any of the soap opera drama llama BS of the Sterling days. Remember any of that from back then? Glad it's over. I think most of the chatterbox conversensationalists went on to failbook or something. The number of forum users sure has shrunk lately... I'd like to think our signal to noise ratio has improved because of it but I'm not sure.

Just a few more items I need to talk about before this becomes a book (too late). I sent a PM to Carl in December asking whether he still has any "boost prepped" Sterling or banana carbs he'd like a competent adult to test for him just as a way to say thank you for pioneering the modded Nikki concept on the forum all those years ago. I wouldn't own it, but just sort of borrow it, and it would be announced publicly on the forum so I'd be a fool to not return it when I'm done. I volunteered my turbo setup as I have full instrumentation and have developed a knack for Nikki tuning by now. That was on the 14th. He still hasn't responded. When I recently checked his forum activity, turns out the last time he was on the forum was the 4th of Dec. He's either off the forums for good or just isn't interested anymore. Probably the same could be said of Sterling not wanting to do Nikkis anymore but I didn't want to bother him.

But now that a little time has passed in the new year, I'm finding myself less interested in taking on a project like this. I think it's because I have four boost prepped Nikkis I built in a production run early last year, and they were built with my philosophy of big primary venturis and stock secondaries for a 13B. See, I didn't feel a need to screw with the secondary circuit. I think it paid off because with boost, you don't really have to make the venturis bigger, and the secondaries are already pretty big from the factory. But because I run 4 port 13Bs around here, I needed to make the primary venturis big enough to still be useful at low RPM in vacuum for good low end torque. This goes against the Sterling/Carl mindset/philosophy of smaller is better because "it keeps velocity up" or whatever. Out of all the carbs I did, the smallest was 24.5mm at the request of the guy I was doing it for, but in the end it turned out to be the weakest of the bunch while the 24.9mm carb turned out to be the strongest. Again in vacuum/low RPM and tip-in. The other two are around 24.7mm. In boost, they are all about the same but I did notice a little bump in power from the 24.5mm carb when its secondaries open. Can't explain that one. It's a bit more fun sometimes, actually. It was the first carb that ever broke them loose in 2nd gear on dry road back before the secondaries were even tuned! Moving on.

I'm afraid the Carl/Sterling boost prepped carb would have the smaller 22mm venturis and incorrect jets and air bleeds for boost. I'd need permission to dig into it for any jet and air bleed changes and I would certainly need permission to dig into any hard parts like venturis just to bring his carb up on par with mine. So if he ever sees this or gets the PM, I'm publicly stating I am no longer interested. Sure I'm still curious, but I think I know enough about these carbs in general that I believe his is just going to be a disappointment and would take way too much work to get it to work right. However I'm not against being talked back into the idea. But the fact remains he doesn't check the forum anymore so I'm just going to close the book on that and move on. It was a cool idea, and maybe he could start selling boosted banana carbs or something if we collaborated, but I'm no longer interested and I don't think he is interested either. Does anyone else think it would have been a good idea?

Oh and before I forget, here is a link to the thread where Carl and Sterling attempted a boost prepped Nikki with that kid, and in my opinion, failed to deliver. Of course the kid could have been a little more competent too, which is also my opinion, of course. Check it out for yourselves. Read through it, get frustrated, and see how far we've come. FB II's thread: https://www.rx7club.com/1st-generati...update-328276/

Jeff20B

iTrader: (13)

I did a little digging on this FB II kid and it turns out he did eventually get the boost prepped Nikki thing figured out himself. Like everyone else who gets into these carbs, the Nikki eventually gives up its secrets and behaves itself. You just have to work and try different things. No idea if Sterling or Carl ever got their boost prepped carbs working.

He's banned now, but his posts are still available. I'm checking several out right now.

Jeff20B

iTrader: (13)

I did a little more digging. FB II went from basically a noob at turbos to someone whom others looked up to for turbo advice. That's a pretty good turn around. He started with a Carl/Sterling carb that didn't work so he sent it back. Then he tried a stock Nikki and it actually worked! It still had the altitude compensator and stock primary venturis. It looks like he removed the choke flap valve, at least. I can't tell what else he did from the pics.

The 3rd carb he tried was a weber for some reason. He obviously didn't like it that much because he then went to a boost prepped Holley, double pumper I think, on an RB manifold. I guess he was never happy with the stock FB manifold. I don't blame him (they're the worst flowing stock manifolds). And a new tubular exhaust manifold built by 61620B on the forum, who also made one for WackyRacer. I wouldn't mind one of those manifolds for my REPU! Obviously the turbo location in the engine bay would have to be different so I'll end up having to make one myself... hopefully at some point this year.

After the Holley wasn't good enough for him, I think he might have gone to a 13B with EFI. That's where I lost interest. I don't know if he ever accomplished the EFI 13B swap.

There's something just so fascinating about a carbed 12A turbo, you know? Makes me want to do one real bad.

This FB II guy (I'm not calling him kid anymore) seemed driven to make a turbo carb setup work in a 1st gen. I can respect that. He tried lots of things and didn't lose all hope when problems came up. I ventured down a similar path but it was to make the Nikki work specifically with boost and make it work well on a mild ported older 13B that obviously doesn't have injector holes in the intermediate plate. I needed the Nikki to work better than EFI and I think I might have done just that. Well, not in the cold running department, but I'm used to carbs that need a blip of the throttle when they're cold. Seems kinda normal to me. I wouldn't want it any other way.

I have virtually zero desire to go EFI anymore. I tried it three times across four different vehicles (pulled the MegaSquirt from the GLC and stuffed it into the GSL-SE but ultimately pulled it all and went carb in both). Glad I went carbed. Less headaches in the GLC as it got an Edelbrock which ran fine right out of the box. And less headaches in the GSL-SE obviously after I figured out the ins and outs of the Nikki. All the N304 EFI stuff was pulled from my car before I got it so even though I had a complete S4 NA setup just sitting there (engine, ECU, complete harness, coils etc), I swapped all of it into a friend's 84 GSL and went old school in my car.

My car turned out to be faster/quicker with the hogged Nikki while NA than the stock S4 NA was in the other car. I tested the RB long primary in both and mine was the winner.

Was the stock EFI transplant worth it in the end? According to the owner of the 84 GSL, no. After all the work, time, effort and resources that went into it, and what he ended up with, it wasn't worth it in the end, but he's fine with it for what it is. No complaints (he even likes the cold driveability because he doesn't need to pull a choke **** - as if that's a big deal, but maybe for him, it is), and I got to try my hand at an EFI install that didn't require any tuning with a laptop.

My car with a hogged Nikki, 74 ported 13B, light steel flywheel and DLIDFIS is just more fun. And the coolest part is you can actually see the top of my engine! No ugly EFI manifolds in the way. Then going turbo with the same carb was the next step which I won't bore you with.

Wow, why did I type all that? Thanks for reading. If you made it this far, you're awesome!

j9fd3s

iTrader: (3)

i aslo got a bum sterling, or rather my friend did. the first one, was damaged in shipping, it just got thrown in a box and the shafts were bent on arrival. carb #2 was bolted to a piece of wood, and was undamaged.

having TWO sterlings to look at was interesting, as one was a fairly early one, and the second one was built sometime later (1 year? 18 months?). the second one had some obvious corners cut, it was assembled and then spray painted, the first was powder coated. etc etc.

so i did what i was going to do to the car, whatever that was, and it ran nicely with the stock carb. so i put the thing on, and it ran like *** and wouldn't idle. we later have found out there is a difference in the metering body, and i was able to take the bent carb, and use that to make the unbent carb work. i'm trying to be brief, it runs ok, there is a little more power, but it has that midrange part throttle miss that they all seem to have, and then i drove it back to back with the P port, and the p port walks all over it. even off idle.

anyways, the P port has a weber and the weber has replaceable venturi's. i think if you read textbooks, they say that the venturi should be about 80% of the throttle size. since the weber has venturi's you can swap, it lets you break this rule, you know what happens? nothing. i imagine if you went waaaaaaaay too big it wouldn't work, but i'm running a 42mm venturi in a 48mm carb and all is well. and lol, the stock nikki has a 28mm primary throttle plate, multiply by the theoretical 80%, and you get 22.4mm....

i also don't quite get the mechanical secondary mod, which seems to need all these other things like the giant accel pump, to "work" when the stock vacuum secondaries are totally adjustable with a spring, no other mods needed. after all that bit where you have to think about modulating the throttle so you don't get a hesitation is where the vacuum carb is faster, because the driver can just mat it, and drive.

for the other stuff, tuning is just tuning, the engine wants what it want, and you need to figure out how to get the hardware to deliver it

j9fd3s

iTrader: (3)

tuning the PP was a great experience. at first its intimidating, because there is all this chaos going on, and it loud, and you're afraid to blow it up, but the engine was really adamant about what it wanted for fuel. so it took a while, but i finally came around and just gave it what it wanted, and it runs unbelievably well.

fast forward a few years, and i've messed with the single zenith on my MGB, the dual Su's on the Tr3 (getting two carbs to do the same thing at the same time is a PITA!), a couple of haltechs, and some other stuff, and if you pay attention to what the engine is actually asking for, you can usually make them run very well on anything.

the contradiction is that the stock engine is pretty happy with anything, and the PP is picky, so tuning the PP is actually easier, once you get past the hysterics.

at this point, i like the immediacy of a carb, it can be fully tuned in a couple of hours, and EFI takes way longer. a carb has about a 5x5 tuning table, and efi is (32x32)+(32x32)+the correction maps