rebel101150

so I was curious, how does a camden supercharger fare with an 84 gsl se 13b? Seems a hell of a lot easier than turboing the engine. I've heard there are other brands out there but I can't seem to find one.

rotarygod

iTrader: (1)

I'm going to go ahead and just give you the responses that 73 other probably people will...

A Camden supercharger is overpriced
A Camden supercharger doesn't make much power for the money.
A Camden supercharger makes less power than a stock Turbo II swap would.
Do a Turbo II swap instead.
Turbos are better.
Turbos are faster.
Turbos make less heat.
Superchargers suck.
Monkeys eat bananas.

I think I got most of them.

rebel101150

the info on the turbo 2 swap is so dated on this site I cannot find a tutorial that even still works based on all the links. The supercharger installation just seems overly simple and here I could buy a turbo 2 modified fc for the price of all the supercharger stuff at almost 6k for FI. I considered v8 but due to simplicity but my engine is chugging along so well I don't want to get rid of it.

EvilJester

their is a reason why most of us don't use crapten SC. If they were so good, and easy to tune, makes tons of HP, is relaibale, low heat then all you would see on this forum is how to's on SC's. Pro racers would be using them if they were all that. Turbo, turbo, turbo.

rebel101150

I'm going to have to find a shop to handle a turbo II swap near PA/ohio border. I seriously don't know anyone. None of the performance shops around will touch a rotary. The words I got were "it doesn't take a good mechanic it takes a lucky one" i'd love to boost the one thats in it, just have to change to low compression rotors but I just don't have the know how to pull that off myself right now because it would be an entire rebuild if i'm not mistaken.

considered buying a friends 12a he ran with no oil and having it machined and fixed just for boost application and learning of porting/rebuilding the rotary.

Jeff20B

iTrader: (13)

Read these two old threads where most are pro Camden with only a few sensible pro turbo posters.

https://www.rx7club.com/1st-generati...s-name-377142/

https://www.rx7club.com/1st-generati...harger-197023/

What is my opinion? I've had a chance to use both. The SC will never be as good as a turbo. Even a small stock S5 turbo blow through Nikki like I've been messing with recently is way better than when I had a 5" SC in a 7. The SC was nice, but the turbo wows me. Yeah, it needs to pass the wow test, and the SC just couldn't do that; it's not even capable of wowing me in the GLC right now (thinking of throwing it back in the REPU where it might do some good).

I could go on, but you need to read those two threads and see how the mentallity has shifted over ten years. It's quite fascinating.

Qingdao

iTrader: (3)

Dated?? Tutorial??


Lindahlish did a by the book turbo swap last year. And droping an engine in shouldn't require hand holding.

https://www.rx7club.com/build-thread...lenty-1026186/

You might be ok with a Camden, but you'll pay more per gained hp. And you aren't gonna see half the power increase a simple turbo can produce.

Just think of the exhaust on a rotary and that should explain why turbos are better. I mean there is a GIANT hole coming straight out of the combustion area SCREAMING TURBO!!!

rebel101150

referring to the faq links no longer working or a majority of the images no longer working in the ones that are still up.
https://www.rx7club.com/1st-generati...q-page-237777/
there was a large archive concerning the swap and almost none of the links worked. I seem to have missed the one from last year you mentioned.

placd1

iTrader: (3)

The age old battle between supercharging and turbocharging still rages on.....

Jeff20B

iTrader: (13)

No it doesn't. Turbos won.

Here is a sad story about a 7" Camden. I was debating whether to tell it or not. Back in '01 when Atkins purchased Camden and were experimenting with the new 7" model, a friend bought one of the first ones for his REPU. It always sounded like marbles rolling around in a coffee can and never had any real power. Plus it would tend to squeal the belt whenever he got on it. Drove it that way for years. Popped two motors. Finally on the third engine, the SC started making funny noises so we took off the carb and looked in. Lots of aluminum damage of the peanut shaped SC rotors with metal dust everywhere. Ok, so we pulled the SC, had it rebuilt. Took from October of '10 to April of '11. Then a week later it died again of the same problem - destroyed rotors. He was like eff this and threw on a good known spare 7" Camden I was planing to use in another REPU. The dead SC sat for another year then Dan took it to his shop. I called once a month for several months asking when it would get rebuilt. Always got excuses. Eventually decided to throw the 5" in the REPU instead and was mildly wowed at the ok low end and all that. Now I'm debating whether to say eff this and toss a turbo in it. There's nothing wrong with the 5", but would I really want it to pull truck duty? They seem to be pretty fragile after all. And if they need to be serviced, will it go back together correctly? My friend's didn't.

I have another story which took place during the peak of Camden's popularity, which would be some time in about 2004. I went to Ken's shop (mentioned in one of the threads linked to in my post above). There were three RX-7s in his shop with Camdens. Yeah, three. I was like, wow, that's cool. So many supercharged sevens. I think one of them was CodeBlue's car. One other was Ken's I think silver car whic had the word "supercharged" in a vinyl sticker on each fender, and the other car I can't remember. Anyway one had the exact same aluminum peanut damage with metal dust everywhere; hence the reason it was in the shop, due to a dead supercharger. Don't recall whether it was 5" or 7". Well either way you can't drive your car when its intake manifold craps out on you, so I'm sure Ken charged a storage fee on that one while a new or rebuilt SC was shipped from Atkins.

Lastly I have one story about a 5" SC that a friend bought before Atkins bought Camden. It didn't have any of the upgrades yet so after it had locked up due to oil starvation, he had it rebuilt with the updated parts. I think it locked up one more time, then he finally got the oil feed right. This was back in 2001. Anyway in '06 or so, I swapped the SC and the engine it was attatched to in a 510 and while the carb was off, I noticed the peanuts were looking like the aluminum was started to move a little. Kinda disturbing. It won't be long until this SC suffers the same fate as all the others. Several years later I got word that the SC or the engine were making funny noises, so the new owner was advised by the previous owner to sell sell sell!

This brings me back to the age old debate I'm having regarding REPU duty. Will a relatively low mile Camden, such as my 5", be able to pull truck duty for the next oh let's say couple of years, until I'm good and ready, both metally and financially, to do a turbo in it? Or should I go for a basic stock S5 turbo and a blow through Nikki right now, knowing it will work a crap-ton better than a Crapton, I mean a Camden? I'm very aware of the limits of a Camden, sure, but the truck already has an awesome long primary exhaust that's both quiet and flows like an RB long primary. The turbo would require a totally new exhaust and a new fuel system, not to mention a bunch of other stuff I won't bore you with. The Camden would bolt right in with zero mods to anything, thus making it super easy. The turbo would require everything to be redone.

So the debate rages on for this one vehicle, but the larger issue has a clear winner. Turbo all the way.

j9fd3s

iTrader: (3)

there is no doubt that a supercharger COULD work very well on a rotary, however the camden the right piece.

back in 2004 we went to sevenstock, we got there on friday, and atkins was there setting up their booth and they had a supercharged FC, the dyno graph was something like 160rwhp.

my friend had just done a street port NA engine, and that did 165...

Jeff20B

iTrader: (13)

Yeah, the age old debate says stuff like: if you're chasing dyno numbers, the SC is NOT the right choice. But if you like to be different, and have more dollars than sense, and if you've already purchased the RB long primary exhaust and have a big low pressure fuel pump like a Carter already in there, and don't care for upgrades that actually lead to real gains, then maybe the SC is the right choice for you. Or if you're not able to do any custom fab but can turn a wrench, maybe the SC is right for you.

Here are some other things to consider. The SC is parasitic down low when it's not boosting. On the other hand, the S5 turbo, from my noob's perspective on turbos in general, is not parasitic down low and actually provides the same low end torque as an RB long primary on an NA setup with a big or similarly sized carb (I'm using a hogged Nikki). The SC never did this and actually felt pretty weak down low, even with an Edelbrock, which is a big decent sized carb for a rotary. I'm talking about right above idle like when you're lazily letting the clutch out and driving slowly in residential neighborhoods. The Edlebrock has good tip-in but on an SC it feels kinda like you're driving with an e-brake on. It also has a slight delay from when you hit the pedal to when it starts to rev due to the spinning rotors inside, kinda like drive by wire actually (I hate that in the newer cars).

You know it's funny. The Camden devotees all say the SC has better driveability around town than a turbo, and use it as one of the main reasons/excuses to be pro SC. They say a turbo only has high end power and lacks low end, making them less ideal to drive around town or whatever. My personal experience has been opposite, but it kept me away from turbos for years. The SC actually seems to have some lacking low end when it's not boosting, and then when it is boosting, it is mildly more powerful than the same engine with a stock or mildly modded carb (like a stripped or hogged Nikki) with the same exhaust (RB long primary). Fast forward to my recent hogged Nikkis on an ok flowing stock intake manifold for NA and then tested with a turbo. The hogged Nikki on an NA setup wowed me with just an RB long primary from low RPM to high RPM (first time seeing 8k on the tach in this car on the fresh rebuild... oops lol). Then the turbo had similar low end but its high end isn't quite there yet. Seems to run out of breath around 7k or so but has a fat midrange that the Camden just can't compete with. I'm fine with this right now and it proves wrong what the Camden lovers always bring up. Again I'm a noob to turbos and this is just a stock S5 turbo at stock 7psi wastegate spring pressure blowing through a hogged Nikki which is kind of a small carb to begin with.

What engine port size to use with an SC vs turbo? Well, according to 84stock, the Camden likes stock to lightly ported "port area" such as either stock 12A spec or 74 spec since it's considered stock in some years or mildly ported in others. He tested a Camden on a bridge or half bridge and it was about the same as a regular side ported motor (before it popped). He said it tamed the bridge's brap. Hmm... As for turbo, the factory did 74 spec for the T2 and FD engines, and you can only go larger from there with more port open time to cram in more a/f leading to even more power, all though stock ports and cranking up the boost, which you can do far more easily with a turbo, is perfectly adequate. Some FD guys make 400HP on stock ports.

You'd think the Camden would respond in kind, but not so much. This lead 84stock to recommend stock ports with Camdens after his bridgeport experience. Then he set a world record of something like 227HP on a chassis dyno with water injection, huge streetports, the smallest SC pulley he could get, a huge carb and the RB long primary. His ports were really big streetports on an FD shortblock which means he had to really hog out the primary ports to get them as large as his secondaries, as they come stock kinda small for the injectors to have decent velocity at low RPM/idle (I'm used to Y and R5 irons which come kinda big from the factory). Thousands spent, I'm sure. But just 227? That's it? I'm not chasing dyno numbers but I think my basic blow through is doing around 200HP at the flywheel right now but I could be wrong. It is more powerful than PercentSevenC's boosted weber setup and drives a ton better too. And for the heck of it, I'm only looking to make 220 max at the flywheel in the REPU if I go turbo because it's exactly double the stock 74 spec HP rating of 110HP at 6k. So it's kind of a hobby goal, not serious at all. But the funny part is I could easily hit 220HP with a very basic turbo setup and just turn up to boost to like 10psi which I think is the limit of a stock turbo anyway. Some people say you can get up to 250HP on the stock turbos without resorting to a hybrid. I think Karack said that.

rotarygod

iTrader: (1)

At SS7 I rode in codeblue's car which at the time had a Camden SC. It may still. I don't know. I don't remember which size it was though. Just getting moving from a stop kicked me back into the seat and I thought it was a much larger engine. However once the car started moving and the rpms rose, that same push into the seat didn't continue. The initial hit was all there was. There was no top end at all and it didn't feel fast up high. Definitely not as fast as even a stock TII on the top end. It was basically fun at part throttle low rpms. That was a long time ago and things on that car could have changed drastically since then.

The thing really holding back Camden, aside from price and reliability, is that of all of the roots based blowers, the straight 2 lobe is the least efficient and oldest design of all and that's what theirs is. Twisted rotors and 3 lobes are far more efficient and now the TWS with 4 lobes and very high amounts of rotor twist have efficiencies right there with the best twin screw units. Even if you could get a TWS on a rotary, the cost would be hugely expensive and would require tons of custom work. Even then would it be a performance benefit over a turbo system? That of course is full of what if's and maybe's. The Camden unit is quite simply the worst of the worst in the supercharger world and that's not even getting into the supercharger vs turbocharger debate.

I don't actually hate superchargers btw. I'd love to see a nice efficient one installed well on a rotary.

rebel101150

no matter what with the compression of the gsl se rotors it seems like I couldn't do either without changing them.But a supercharger would be pointless is they tear apart like that. i'd love to have a turbo but seem to be hindered in that front without tracking down a turbo 2 and doing a swap. i'd love to do it but the wiring is what gets me, i'm not experienced enough to pull it off with swapping the computer (actually a software developer for a living which is why it's discouraging). too bad there isn't a place I could pay to perform the swap locally.

Jeff20B

iTrader: (13)

Um, my car has S4 NA rotors which are 9.4:1, same as GSL-SE and it does fine with a turbo. The engine is a 4 port (nitrided R5/Y irons ported to 74 spec). I have to get 92 octane gas and run a semi-locked distributor. It is 0 degrees at idle, like stock, but then only advances out to 10 degrees or so for engine safety. Much better than fully locked for driveability and starting. The engine gets what it wants when it needs it. Only downside is part throttle cruise in vacuum only gets 10 degrees instead of 20 like stock, but whatever.

Go blow through carb. It's the perfect way to start out. Simple; works without an intercooler. But then I see you have a GSL-SE so you're already starting with EFI. Well, that's where my experience ends. Good luck.

rebel101150

just got off the phone with a friend about this. I had no idea, I was told I would blow the engine. I was worried about that. Don't I have a 6 port though? It would mean changing it if I wasn't mistaken. I'd love to just turbo it the way it is and convert it to carb, that's my experience with previous piston engines.

rebel101150

sent you a PM jeff20B

Jeff20B

iTrader: (13)

rotarygod, speaking of the initial push back into the seat, my friend's REPU had that too. Then nothing above it. Sad. Then it would start to have marbles rolling around in a coffee can and if he continued to keep his foot in it, there would be a big cloud of gray smoke out the back. I suspect some of that gray color was from aluminum particles of the lobes self destructing lol.

I'm about to say eff it and pull the SC from the GLC and throw it in the other REPU if I can come up with an engine that matches the intake manifold (4 port old school 13B). Why? Because I recently drove the GLC for the first time on the new short collected 2.5" exhaust with the Camden and it failed to wow me. The wow factor is what I build these for anymore these days. If it doesn't wow you ,what's the point, right? Anyway the SC is in the way in the tiny engine bay, so I have zero access to the header to pull it and mod (cut/chop/weld) for a long primary system.

You know as well as I how much nicer a long primary is on a rotary than any other configuration. Just letting others know.

Anyway the last time I tried the Camden in the GLC was back when it had the smaller short collected 2" system made from all RB thickwall tube (only about a 1.75" to 1.88" ID - that's small!!!) and yes it failed to wow me back then as you can guess. I held out hope that the new correct 2.5" exhaust, using an FC header modded to fit the chassis, would be the key to success. Nope. The SC actually responded better in the REPU for some reason. But now that I have turbo aspirations, I'm planning a REPU turbo install and have most of the parts gathered already. So then what will go in the GLC? Either an RB Holley or a hogged out Nikki. I'm thinking hogged Nikki because they are extremely nice to drive and easy to tune. No stumbles like big V8 carbs turned sideways. I betcha it will have better power or better feeling power/percieved performance than the SC, too! This frees up the SC for the other REPU if I can cough up an engine for it. Or just swap Camden intake manifolds to fit what's in there now (6 port S4 NA shortblock). Let the SC pull truck duty until it's dead. No?