I just got the NOS power shot system. I am installing it on my mazda RX7 with a small block 305 in it. it has a mild cam, single plane intake, holley carb. what I"m wondering is do you think I can pull off a 150 shot ona 305? it has about 3000 miles if that on teh rebuild. thanks

 

I've successfully run 100 hp levels on a continual basis in an old 305 tpi I had. It was completely stock minus a set of AFR alum. cyl. heads. It never even burped. At the track I occasionally used 125 hp level, but never tried 150 hp. If you want to reach that level I would suggest starting out slow and small. Try 50-75 hp jets and tune the system for optimum performance. As for the 305's durability, it is definately an issue if the bottom end is stock. Personally I think 305 's are good for boat anchors or paper weights not performance. The simplest way to view it is why go with a 305, parts for 350 are more available and even cheaper in most cases too! But, if you intend on keeping the 305 plan on staying on the low side of 125 hp jets. Unless reliability's not a concern, in that case use what ever kit you want the sky is the limit.

 

reliability isn't a HUGE concern. I would like to finish the season though. if possible.

 

You put a 305 in an RX7? Why? Power to weight ratio? Just what you had lying around? If you have some pictures lets see them. In all seriousness, to intelligently inform you on your application some serious info needs to be provided! We can all talk about what other guys have but seldomly answer questions about what we have. Plainly, be specific! Getting a reliable combo is based on how much and how reliable the info you give is. If you already have the nitrous system tell what manufacturer, part numbers, or type ( dry or wet ). I'm under the impression you have am older carb version 305 and intend to mount a plate between the carb and manifold. If this isn't right be as specific as possible on the induction system, ignition system, and fuel system. Remember take a system approach and you won't be dissappointed!

 

I know the NOS kit your mentioning, and yes I reread your intitial post, so I know your running a carb. Please give a little more info. Remember NOS does sell that Power Shot sh@t that fits in the aircleaner assy. Thats why I'm asking for specifics. Later!

 

no I have the plate system on order. the one that mounts below the carb and between the intake. and as far as ignition all stock HEI I think I will add a MSD 6A before I try the 150 shot though.

EDIT: what is the difference between a wet and dry nitrous system. like I said I'm still pretty new. I know I can install it fine, just don't know all the good stuff :-)

 

here isa picture of it. I have a holley carb and edelbrock single plane to put on with the nitrous too

 

I like seeing foreign stuff getting detroit muscle transplants. Great power to weight ratio, might want to think about stiffer springs up front to accomodate the extra engine weight. As for the difference in dry vs. wet NOS systems, look in the forum, many threads are currently going there. Good luck on your project. By the way upgrading the ignition system for NOS is a must, don't forget colder plugs and a sufficient fuel system. Things only work well when the entire package has been optimized to work together. Later!!

 

When it comes to carbs stay with the wet systems, they work great together. Dry is only needed when the intake was only designed to flow air, i.e. MiniRam, SuperRam, or stock TPIs. So as a rule of thumb, if there's a carb go wet and if there's injectors go dry. Later!

 

Prolly for the same reason I put a 350 in an Astro van

Wet flow is when the nitrous system injects both fuel and NO2. Dry is when it just injects NO2.

 

I have considered a TPI in a second gen RX7, I like the styling but I would be afraid to get too carried away power wise for the same reason as the datsun 260-280-300 to SBC converts and the fiero V8 converts. rear diff/drivetrain failure. I would use a th350-700r4-T5-T56 in the conversion but I kill 7.5/7.625 f-body rears. how does a little 6" unit survive?

 

maybe a 283 TPI would be the ticket! low torque awsome HP! see my 283 TPI thread: https://www.thirdgen.org/techbb2/sho...ight=TPI+cents

 

it is getting a ford 9" and a 700-r4 this summer. have all of it just need to put it in.

 

another person who lives in the blasphamy world of boingers in a rx-7

the wankel gods cry on this day


but I can understand it on a first gen
the motors they used kinda suck back then


I would mind putting a 400SB in a frist gen myself though to be honest

have you ran it at all? if so how does it do

 

my impression of a wankel drag car reving up and launching; "RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR(clutch dump)----- ......... ------BbrrrrrrrrrrrrrRRRRRRRRRRRRRRRR!!!!" a dubious lack of torque second only to its lovely reving, man do those suckers rev.

 

hey I don´t have a problem with lack of torque on a launch


I just dump at 3500 rpms

 

My friend had a great second gen 86 gxl-se RX7, I loved that car it was like brand new, low mile, and flawless. when we rode around he would rev it until the warning buzzer sounded, it was really cool. but when we went light to light with me in my slow as hell 4 speed worn out 82 305 z28 (145 hp when new) he would get killed killed killed from light to light even if he red line launched. I noted very little tire spin on his part and some on my part. he would run neck and neck from any rolling start. I lways wondered how a turbo version of his car would go. in like 92-93 I was living in calif, every week at sears point there was a guy with a turboed race IIgen RX7 he ran a company called mostly mazda's (I wonder what he is doing these days) he had no miles of spagetti under the hood just the motor and the turbo and his lap top he ran like 12's at the time he would launch at ungodly rpms too but the the car would still bog.

 

I have no issues with bogging as long as I keep the car above 3500rpms when I DUMP the clutch.. not slip but flat out dump.

if I go below that then yes I can have a small issue with a bog. but generally not bad.

if your friend was redlining the car and dumping the clutch and still bogged the car then he had some SERIOUS tuning issues or some 10"+ wide slicks. if I dump at anything above 5000 I will spin tires al through first gear, with 205's on the back


the torque output on these cars is around 138lbs/ft for a 86-88 and I think somewhere around 146-155lbs/ft for 89-92 least for peak power

from anything of 2000-7000 rpms it is prolly no more then maybe 20lbs/ft less then peak power

 

also just as a side note

a 82 z-28 with 145hp I would give a good race against if not win when I was stock. car is something like 146hp at 6000 rpms 138lbs/ft at 3800 rpms, 2625lbs, stock 4.10 gears,

the light wieght and those 4.10 help out a lot on the that launch

big problem is though these cars are prone to tire spin and he might have had a lot of it even though you didn't hear it. the IRS on these cars doesn't make them the best launch car there is

 

no tuning issues-just bone stock, nothing to tune really. the car ran great, like I told you it was neck and neck if we were rolling. dont get me wrong this is not bash the wankel time. one thing you forget is that we are at 6000 ft altitude here. his car with two passengers couldnt even appproach 100 mph on the hills here which extend up to 8000 feet. I do know that when you take a car from this altitude down to anything near 1000 ft it feels like you are running nitrous. this would explain why it was hard to turn a tire here. there is no doubt an RX7 can fry 'em just not very well here.

 

that might explain it, least in part

I am somewhere near 2500 ft at my location
and even at 3000-3500 still roast them but overall not as much speed.


and by lack of tuning I wasn't really meaning like jets, or timing, though they where included, but more along the lines of plugs, wires, oil(you would be shocked at how much of a difference that can make) stuff like that


and another thing I forgot to mention as far as these cars spinning off the line.....

they have something like a 30lb flywheel (makes me sick with how heavy it is) as well as 10 puunds per rotor and there is two of those bastards, and proly another 10-15lbs for the "Crank"

all that stuff should be very hard to stop when you dump the clutch.

part of anotehr reason I was thinking something might be off

but alt I am sure has the biggest deal

 

hey, yes the car runs VERY well. we still have a couple of little bugs to work out but for the most part it totally kicks ***. we got the car for free so the only cost we have is the motor,tranny,driveshaft and rear so far. it is a very budget car, we hope to get ti to the track next month. I'm hoping for high 11's without nitrous 10's with. I'll keep everybody updated.

 

I picked his brain about the car today because he moved to florida. he said after driving it for 8 years he really loved it. the apex seals were staring to go or something and it smoked just ever so lightly. he now drives a mazda pickup to haul his scuba gear around since a tour bus ran over his RX7 while it was parked.

 

white smoke was prolly the coolant seals going

blue smoke was the oil seals

apex seals don't really cause that much for smoke unless it is the black smoke.... and that can't be good

 

black smoke is when you're burning gas, oil, and antifreeze all at once, kinda like when the bearings on 2 of my pistons decided to snap last month Valve cover seals were burnt up in the spots where the two pistons with snapped bearings decided to hit the heads.

 

I can get black smoke without going through all that trouble...

just adjust the mixture on my car so rich that it barly runs...

stinks really bad though... I mean really really realll bad

 

yeah and with those rx7's...weve had a few at work that the boss took trans fluid and poured it into the intake while revving to bring some compression back into that damn wennkel p.o.s.(he said something about making the 3 seals swell back ??)
all i know is it worked long enough to wholesale the freaking overrevvng things lol
oh abd b4c,thanks for that link to the nos posts,even tho i searched them before ;o)
peaceout!! :rockon:

 

wankel p.o.s.???
why would you say that.
think it is a good enough motor design if not better then a piston... just hasn't had the development time that apiston motor has


the ATF into the intake is to get rid of carbon build up
the seal (kinda like your piston ring) will actually move inside the rotor groove and if you have carbon build up it prevents it from moving so you lose compression.

as for being an overrev car I think it's kinda nice being able to have a nice flat powerband that doesn't just move from 3000-4500rpms or anytyhing but rather from 2500-7600rpms almost nice and flat and with the 4.10 and light wieght comes in handy

 

bzzzzzz bzzzzzzzzz bzzzzz my hotrod wenkel listen to it rev again bzzz bzzzz lol...
i just prefer a v-8..
hey is it true that they were thinking about bringing the wenkel back??????

 

they already did I think

that or they are making some final adjustments


250hp out of 1.3L without any turbo or power adder what so ever


and hey I prefer my wankel so that must mean those V8 pieces of crap just suck I mean boing boing boing.... yeah listen to me reve again boing boing boing....

 

lol! whatever dude...its thirdgen.org no rx7revver.org lol
:rockon:

 

hey Take it easy, I happen to like 2nd gen RX7's, I been eyeballing one at the wrecking yard and I figure its either that or a chevette for an LS1 swap. Lookout!

 

b4c...HELL YEAH!!! :rockon: i looooove ls1 motors... you have no idea how bad i want like a 2000 ss z !! working at a used ca rlot i get to drive em all from honda ***** rockets to vipers...but price wise/power...i looove ls1 equipped camaros/firebirds...(although that 01 zo6 i got to drive was more fun to drive lol)one of those ls1's in a tiny car like a chevette or caviler all tubbed out would decimate all lol...
plus it'll sound alot better and last longer than a damn wenkel lol
sweet!! :rockon:

 

with that little chunk of alum V8 who needs tubs?

 

Wow, this board is becoming all to quickly populated by immature bigots, eh? Anyway, RX7speed, I respect you and your car. I was always fascinated by the wankel design - definetly ahead of its time.

Oh yeah, dry/wet nitous systems are neither partial to carborated nor fuel injection engines - It just depends on how much nitrous you want to flow.

Nice job on the swap, now just do a little body work and lay on some paint, and you will have yourself a real hot car

 

hey I resemble that remark!, the first engine I ever built was a model of a wankel (clearplastic) with life like motion. my first car was a 68 beetle, and my first Hi Po swap was a 1.6 to 1.8 in my datsun B210 about 15 years ago. Im actually an OG sport compact guy.