snub disphenoid

Let me start off by thanking Camden Superchargers and Atkins Rotary for making this supercharger kit. . I think it's great that you were willing to go out there and make a kit as complete as yours is. Lord knows I would still be working on fabrication if I did a custom setup. Let me also point out that this the opinion of a youngster to the car scene. With that said, there are some issues:

I'm not going to nitpick tiny **** like how the A/C line gets in the way on 86-88 coupes, because I never used my A/C anyways (word is that it'll work if you bend the line, and it also works fine on verts and Kouki FCs). I don't really mind that stuff, it's just what I find to be one fundamental flaw in the entire kit, that you can't really do anything about.

It's so damned old fashioned.

The supercharger is an older design that's not as efficient. The fuel control is extremely primitive. The belt pulleys will slip.

In fact, for my application I'm going to have to switch to an electric fan to keep the belt from slipping in first and second gear, and because I'm running bigger injectors I'm going to most likely switch to a standalone ECU. I've had problems with ignition breakup and detonation. The idle is still really not-normal, and this $3200 kit is quickly turning into a $5000 ordeal.

With that said, I don't give a damn. I'm finishing this install, no matter what. I've already got a taste of what to expect and I'm very, very excited. I've just become a little bit frustrated with everything that wasn't a problem before that has become a major issue now.

If you're going to purchase their 6psi kit, slap on only the kit and not worry about anything, you'll be treated to a pain-free and simple installation followed by a substantial increase in power. If you're like me and decide to run 8psi on upgraded injectors (and you want the car to run almost like it's stock), you'll run into some problems. These aren't problems that come from the kit, but rather problems that come from your car. Make sure your ignition system is well maintained, make sure you get a boost gauge, and for god's sakes don't think you can run on a stock computer, because you can't if you upgrade your injectors.

It's a great kit, but if you're shooting for more than 200rwhp from a supercharged car, you're going to need more time and money than you think. And that's the problems people are reading about in this forum. It's the fact that you have to have a car that's going to be able to support the supercharger. Your engine must be well-maintained, your electrical system must be in good condition, and you must keep a little extra cash saved, just in case you find problems, like I did. It's a great kit if you're looking for plug-and-play 180rwhp (and it will do that, believe the Atkin's folks), but in my case I got greedy and now I'm paying for that elusive 20, 30 more horsepower.

And to all those who are eagerly awaiting my dyno sheet, tough luck, because the local dynapack broke down. Looking forward to next week.

RotaryEvolution

iTrader: (30)

sorry to hear, sounds like a huge ordeal for a little HP, if i had thrown that kind of money at my car it would be 400+ HP.

RX7FROMCAL

i agree lets add mine up. kit 3200.00/ injecotrs 200.00 labor 700.00 fuel pump 100.00 two dynos 200.00 apexi 2 piggy back computer 350.00 gadges 300.00 with labor new high flow cat 150.00=5200.00 thats where im at so far.but i love it sooooooooooo what can i say i knew going into it , it wasnt gonna be cheap. to me its worth it , but i agree with some issus that wernt a big deal now are!!!!!!!!! but thats what we get when we mod a car. we either put out or shut up , thats what i say!!!

RotaryEvolution

iTrader: (30)

i think his point was that for a 'kit' it was less than expected. i wouldn't be super happy either but i try to expect the worst and hope for the best.

ddub

Interesting thoughts.

One issue I have with what you said, though, is about the ECU. There are people on here that have ran the n/a ECU on upgraded injectors and turbo, Aaron and Sonicrat, without problems. Why do you think the ECU is such a problem? Not trying to be rude at all here, and a standalone will ALWAYS be better, but they have ran upgraded injectors fine.

Second, referring to this line:

You're talking about the 6psi pulley that the kit originally comes with, right? That's how I read it but please correct me if I'm wrong here. How do you explain the recent results of rx7fromcal then with his 10psi pulley? I'm just curious what you think about this. In my personal belief it needs some type of intercooling, but some people don't seem to think that's the case. So how is this 180rwhp obtainable on 6psi? Again, just curious on your thoughts here because we really only have one 2nd gen person with this kit so far with a dyno and he ran 10psi.

Third, you talked about detonation and ignition related problems. When is the detonation happening? Are you sure it is in fact detonation? What ignition problems have you been having and at what rpms is this happening at? Is timing set correctly? I assume so as people have said to check it in the past to you when you were having some of these problems but still thought I'd ask.

Anyways, those are my questions and concerns. Don't take any of this as rude or nit-picking at you as I truly am curious about these things and would like to hear others input. I too was once interested in the camden kit, this is why I want to know.


I'd also like to see someone with this kit go to the track rather than just the dyno, that will show a lot more than just a dyno (how the torque curve really helps).

snub disphenoid

The stock ECU may very well be the fact that I chose to run staggered injector sizes. I think that if someone were to upgrade their injectors to TII injectors, they probably wouldn't have the issues I have had with detonation. With my stock 460s as primaries, I have to run 20% rich as I approach 3800rpm, but once I reach 3800, the secondaries start to kick in, and I get a bog followed by a rush forward (only really noticeable in the first two gears). I consider going standalone because I would like more precise fuel and ignition control that is optimized on and off the dyno.

My thought (and it could be wrong) is that RX7fromcal exceeded the optimum efficiency range of the supercharger. The Camden supercharger is a two-lobe roots-type blower, so it's certainly not the most efficient method of forced induction. I think that because he ran so much boost without an intercooler, his supercharger ended up making so much heat that he effectively heated his intake charge to the point that he made as little power as he did. If you think about it, what would happen if you ran a Turbo II at 18psi on the stock turbo? Only MY dyno time will be able to test to see if this is true, though.

The first time we did wideband tuning, we heard what sounded like ignition breakup starting around 3000rpm. When I pulled the O2 sensor, it was white(indication of lean condition), and not dark like we would expect it to be if it was running rich. I went ahead and ordered up a good heat range spark plug, a good set of wires, and threw those on, but that didn't take care of the problem. I then checked the wiring on the injector connectors, and noticed that one of the wires had popped out of the butt splice. We took out the butt splice and just soldered the wire back on. The problem became less noticeable, but it was still happening around 4500rpm. I checked the other injector connector, and the connector was actually breaking apart, so I had to solder in a new one. I fired the engine up, ran insanely rich settings on the SAFCII, took it out to a back road and let it run to redline, and it did, without any incident. The noise hasn't come back since.

I would like to run the car at the track, but belt slippage is really limiting my 0-60 times. I only see 3psi in first gear, 5psi in second gear, and I usually get to 8psi in third. I MIGHT run the car at the track, but we've been having rain around here lately and the track may be closed.

ddub

Have you thought about running larger primaries? I would've thought this would've been a good idea, at least to me, since the supercharger is making boost earlier on. Not only that but you even said you had to add fuel before the secondaries kicked on, it might at least help the situation a bit.

Aaron Cake

iTrader: (1)

Since when? Many people (including myself) have run larger injectors on both the stock TII and NA ECUs, and have absolutely ZERO problems with drivability and smooth running. All it takes is a little input from an S-AFC.

This is true of any modification.

RX7FROMCAL

With My Belt I Just Had To Keep Tightning It , Every So Often , Now Its Fine. As For The 10 Psi Gary At Camden, Seem To Think It Was Just Fine. So I Dont Know, Im Getting Another Pully Set Here To See If We Can Get More Boost. We Shall See What Happens. Will Kepp Ya All Updated.

YearsOfDecay

My Next project will be to take an second gen base and supercharge it.. The SC might not give an increadible amount of HP... but guess what it DOES give you... LOW END TORQUE.....

Heres my plan.. right from the start its going be a standalone ECU and a roots type blower. I haven't decided on what type of blower yet, but I'm going for low to mid power, so a centrifugal type (paxton) supercharger is probably not what I'm looking for.. Whatever supercharger i pick... it will come from a junkyard or an E-Bay parts dealer

I think the problem with the atkins kit can mainly be attributed to the fact that its designed to work with the stock systems, thereby throwing a monkey wrench in the works right off the bat.

As for the belt slippage... I'm going to run a ribbed belt system, which, is going to require some fabrication of pullies,

The whole reasone I even want to try this... A) Im nuts b) I got a goot motor core sitting here and a spare Haltech....... why not???

owen is fat

sorry to hear. BUT, there are guys I know who run into the sme exact problem when running a comptech superchrger setup on a Honda S2000 or a Jackson Racing supercharger on a Prelude-H22 swapped Civic Hatchback. the quest for the utmost power reveals many other systems inbility to keep up with the demnds of the new power. my buddy with the S2000 decided to forget the entire supercharging project after he wes 95% done with all of the other mods to support the power because the time it took to get it done and done right was totally dragging him down into depression.

since then Ive learned it might be more fun to keep things simple and get to enjoy them rather then go on the quest for the most power you can squeeze out of a particular motor setup and thus suffer the consequences, whether its downtime or money or lack of usability on the streets.

anyhow, good luck to ya.

YearsOfDecay

Also.... you must realize that Atkins is trying to make a BOLT ON supercharger kit, and make it relatively simple to set up... so they can't be giving a bottle of whoop *** in a box because they must market to everybody... not just those people with acces to welders and milling machines and a degree in electronics to set up their cars... They are a company and must deal with liability and all that other crap that I don't have to worry about with my tinkering on my own car!!

their SC kit does exactly wht they say it does, but, like you said, if you want to get more out of it than what they advertise... you are on your own...

I've no doub't I'll be able to get 250 RWHP and gobs of torque out of my project.... but, everything I do is going to be pretty much a one off custom job and thats NOT marketable...

I went through this with my FMIC.. It frekin works GREAT... for ME... but to try and market MY Kit... not happenin.. too many people wouldn't be able to fabricate their own pipes, too many people just can't live without their air conditioning.. too many people are scared to death to cut a 3" hole in the metal beside the radiator.. too many people want to run an e-fan on a 400 HP car in 90 degree heat... Its just not worth the time and hassel to market something like that.

The guy down the street has the atkins kit, but he barely speaks english, so its hard to really pump him for info, but he gives it a big thumbs up!!!!

OverDriven

Wait...are you telling me that the kit only gets you 180 RWHP? My god what a waste of money!

-Joe

YearsOfDecay

that brings up ANOTHER point... Trying something new, something that requires lots of mods to your car.. should not be done on your ONLY car.. you will just drive yourself INSANE and into a fit of DEPRESSION because you spend more time working on your car than driving it.....

I have a 1985 beat Up Piece of **** cheavy s-10 that i drive through the winter... During the winter, my TII goes up on jackstands and thats when i begine my projects... Living in PA.... December through March is no time to be driving a sports car anyway, so a second vehicle is a must.

If i don't get something done this weekend.. it doesn't matter because the car aint leaving the garage until the salt is off the roads anyway..

I remeber trying to mod my 89 GTU when it was the ONLY car I had... I blame my receding Hair line and the facial tick i've picked up on those weekend projects trying to get everything done and working before work on monday... thats no fun at all!!!

YearsOfDecay

HP aint the only thing.. the torque specs... someone needs to put up dyno results... the torque curve shoud be expanded greatly in the low to mid range band as well as top end..

a SC car should be able to whoop *** on track day against any turbo car with simial HP numbers cause of the gain in low end response


Also... NO TURBO LAG... you hit the gas.. there it is.. if you haven't driven a SC car... its a different ballgame....

remeber.. your taking a car that had MAYBE 125RWHP and bumping it up by 50 at the rear wheels.... thats like 40% more power!!!!!!! And its BOLT ON, you have to PAY for that!!!

ddub

There is a dyno graph up, rx7fromcal put his up in the other thread.

And no not all superchargers have instant boost just from hitting the gas. The camden unit for example doesnt show peak boost until, iirc from what was said by snub and rx7fromcal, about 4krpms which is similar to a turbo.

And no it's not going from 125 and adding 50. So far the only dyno graph that has been posted by a member on this forum was rx7fromcal and he has an s5. Starts with ~136rwhp after a 15% drivetrain loss, he got 173 or something after tuning so that was a 37rwhp increase, not 50.

casio

so what is the most efficient form of supercharger; both pos displacement and centrifugal? i've considered doing like what yearsofdecay is thinking, but centrifugal. first and foremost, for me, would be the haltech (unless someone can sway me from doing this first and going straight to the big S/C). i would like a big supercharger, though; one capable of breaking 370whp (mainly just so i could beat the number [yearsofdecay?] posted in the other thread).
also, i'd be looking for used or new, but cheap, like on ebay, superchargers. any recommendations besides Vortech? its the only centrifugal i know of. or are there some pos displacements that easily can use an intercooler?

[not trying to threadjack, i swear. i had good intentions of staying on topic a tad more.]

hornbm

Ive personally driven dan atkins rx7, and that thing made boost very low in the power band, very very torquey. Keep in mind this was with a holley not fuel injection.

I used to work at mazda, and I ve had a chance to drive stock and modded FD's, and let me tell you dans first gen can hand some of those cars its *** on a silver platter. Dans car was just overall more fun to drive. I was pinned in my seat everywhere in the power band.

I plan on installing my own camden kit, however im going to be taking a different approach. With my current setup (see sig) Im runing high 14's. Keep in mind my motor is stock port.

What I plan to do for next summer, is use a rebuilt streetported S5 turbo block. Use a racingbeat street port exhaust system. 7" camden supercharger, with a 48MM weber side draft carb or bigger. Also going to switch to a turbo II tranny, a torsen differential and 4.44 gears in the rear. Plan on using the 10PSI pulley

I expect to get 13s and mabey high 12s... who knows mabey lower than that. But this thing will be completely streetable. I'll have track time slips and dyno graphs when summer rolls around, stay tuned!

ddub

Why would you use a TurboII block? Ported n/a's have more room for the size of the ports on the secondaries, not only that but the n/a has larger secondaries to begin with. Turbo rotors or n/a? Hope n/a.

How does the holley make any difference? This doesn't change when boost comes in, plus FI is always superior to carb when properly tuned.

snub disphenoid

Don't talk or cry about the price. Think about how much money it takes to fabricate custom intake manifolds, pulleys, and fuel rails. If you can't afford it, don't complain about me. Do you see any other supercharger kits for the RX7 available? Do they cost less than this one?

I don't even care anymore. So long as I get this done, I'll do what I takes to get this car up and running ship-shape. I'll try to get you guys my own dyno graph soon, as soon as the local dyno gets fixed.

ddub

There was another supercharger kit for n/a FC's years back, it was in the 2500ish range IIRC and was a complete bolt on kit. They stopped making it, though, because there was no interest. They sold some, and I've seen a couple of the kits floating around still that people were selling, but they didn't sell very many.

casio

was that the one that couldnt sustain over 7000rpm? man, its been awhile since that one's been brought up. i forget who made it.

edit: possibly the Nelson..?

ddub

Yah Nelson sounds familiar. If I recall it could sustain higher rpms just fine with one or two changes to something, it was an easy fix.

ddub

Yep it was a Nelson. Here's a pic of the setup a guy was selling a while ago on here, I almost bought this.





Interestingly enough apparently this kit was able to pass Cali emissions too.

casio

i remember hearing about one that overspun at 7,000rpm. something like taht doesn't sound like an easy fix, but thats neither here nor there. looking at the picture, i would believe the Nelson is a Centrifugal Supercharger. because of this, the kit doesn't replace the intake manifold and such making the kit, i would think, much simpler as far as R&D. personally, i would want a Centrifugal for the ease of adapting an intercooler. nonetheless, Centrifugal and Positive Displacement superchargers don't really compare with one another as far as price is concerned (in my humble opinion).