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-   1st Generation Specific (1979-1985) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/)
-   -   Motor's in the car! (V8 warning) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/motors-car-v8-warning-201472/)

MarkPerez 07-02-03 12:58 PM

An 89 H.O. very cool, rebuilt to stock specs ?? Chevy small blocks are good because of there interchangability
and because of there front timing cover/water pump they are almost 1 foot shorter, so they will fit into just about anything ( T- buckets ) ETC. and are much cheaper to build. Just don't kill yourself with that rockett.
Again, I LIKE IT !

DriveFast7 07-02-03 01:05 PM

looks like fun. nice work.

'85 GSL 302 07-02-03 01:55 PM

Thanks for all the praise guys.

I'll keep you guys posted on all the specs when it's up and running. I'd like to get some corner weights of the car so I can tell with 100% certainly what the weight balance is. I know for sure though that it'll be close enough that some suspension tweaking will make this thing handle very well. Plus I am planning on upgrading to aluminum heads down the road which will shed another 50lbs off the front of the car.

excitingleopard 07-02-03 10:22 PM

I praise you for working hard at your project. I am not really a "purest". But for the love of rx-7's, can you seriously give me a reason as to why you did it? [serious question] Other than low-end torque (really doesn't matter even during the 1/4 mile) what is your reasoning?

I am just curious about this fastenation with V-8's.

White84SE 07-02-03 10:37 PM

One of the biggest reasons I can see is power level versus stress level on the engine. Think about it.. NA, it's REALLY hard to get 300hp out of a rotary. With turbocharging, it gets much easier, but the fuel costs go up with the necessary higher octane and so does the risk of turning your nice turbo'd rotary into pretty pieces of shrapnel. It's incredibly easy to milk those kind of power numbers from a domestic V8 and it'll do it on 87 octane and be trouble free for many, many miles.

'85 GSL 302, engine bay looks wonderful and I'm glad to see you're keeping a T5 under it, rather than wimp out and go slushbox..

--Danny

excitingleopard 07-02-03 11:11 PM

Does the added 100 HP outweigh the heavy-factor of a V8?

i.e. does the V-8 really make the seven faster? If so, why didn'y Mazda make it with a V-8?

'85 GSL 302 07-03-03 12:06 AM

Reason: Build me a 12.5 second RX-7 that takes 87 octaine gas, and will run for 150,000 miles for $3000 including the car. It's a pretty difficult thing to do. Oh yeah, and it's got a fully rebuild motor, tranny, and new driveshaft. Not enough? Build me a rotory motor that's capable of 700 relyable horsepower? The swap basically opens up nearly endless possabilities, where a rotory would be nearing it's limit on relyable horsepower. I have 3 friends with turbo 13b's, all have killed their motors in the last year. The 250hp TII had 120k with near flawless maintanence and care, the FD had about 350hp on an 80K motor, and the 470hp FD had very few miles when it blew. I've never really trusted a Turbo'd rotory motor, and the NA ones are less than streetable in the 300+hp range.

Sorry, I'm really not trying to start an argument or discussion. Just telling my feelings. I know there are relyable turbo 13b's, just never seen any.

I can't tell you why others chose to do a V8 in their RX-7's. I chose an RX-7 for my V8. I already had the motor, i just chose the platform. I got the RX-7 because they're cheap as hell, are light weight, and can handle exceptionally well. There's also a wealth of parts availabel for them. Yes, the power of the V8 overcomes the weight disadvantage. I'd say trippling the HP while only adding 200lbs is worth it IMO. Are there other paths to take, absolutly. There are 100 different ways to build rotory motors to be fast, and to each his own.

As for the tranny, this is a road race car (eventually). I don't feel like having an auto track car. That's just slutty. I really shouldn't have put the shifter in the car yet. I've spent probably 35min. total in the last 4 days shifting the car on the jackstands. I really could be getting more work done....

Mazda didn't have a market for a 2500lbs V8 when they made the FB, but they did have a market for their rotory motor. After that, as many people have said, a V8 RX-7 wouldn't be an RX-7 any more. Not to mention a manufactures goals aren't always to make the fastest possible car.

'85 GSL 302 07-03-03 12:10 AM

Oh yeah, and not to mention I'm pretty sure Mazda didn't have a V8 to put into the RX-7. You guys probably know more about it than I do though. But I doubt they had the resorces until they became Ford's property. After that, why would Ford build a Mustang killer and put a Mazda emblem on it?

Winnipeg85GSL 07-03-03 04:37 AM

Wow, looking good. I was running stock rims/cheap tires on the car for a while because I was concerned about the rear-end going off like a grenade. (I have basically the same setup but it fits under the hood ;) ) I got tired with spinning through 2nd gear, 1st is useless and I never use it anymore, and half if not all of 3rd gear. I bought some '83 Limited edition rims and threw on some Nitto drag radials. The difference is amazing and the car FLIES. The rear hasn't had any problems and the swap had been done for a year.

I'm taking it to the track for the first time July 12th, I'm expecting to see mid 13's which I think is conservative for 220 RWHP and a light car with traction.

http://images.cardomain.com/member_i.../316506_14.jpg

They don't suspect a thing, that is until I start it up. Even then people think I'm just a ricer with no muffler somtimes. :rolleyes: :rolleyes:

'85 GSL 302 07-03-03 09:31 AM

What size 555's do you have on the car? How is it in the rain?

Cloud 07-03-03 09:53 AM

How wide are the LE rims? I've got a set of 14x6 Weds mesh rims and a set of Panasports - probably going to go full-circle with the pissing off of ALL purists and put BFG DR's on the Panas, but the thought has occured to me to leave them on my daily driver and use the 14's for the DR's...

My v8 will be running a lot more power on hose, but I do agree that the tires will and should be the fuse for the setup...

fatboy7 07-03-03 10:08 AM

I don't get how BFG DR's on pansports are supposed to piss of the purists.....

BFG DR's are good tires, but they wear really fast. The thing about the BFG's is that they really don't require much warm-up to get sticky, whereas Nitto 555's, for instance are almost as sticky, but require a burnout to get there. When they are cold, they're like most street tires, and last more like regular street tires.

'85 GSL 302 07-04-03 01:36 AM

I guess becuase RX-7's aren't suposed to be drag cars or something. Kinda lost me on that one too.

Winnipeg85GSL 07-04-03 03:21 AM

The Nittos are 205/55/14's They are better in the rain than my previous tires. Also, the dry traction difference is unbelievable, the car just squats when I floor it in 2nd, although its probably not to easyon the body of the car.

Cloud 07-04-03 08:39 AM


Originally posted by '85 GSL 302
I guess becuase RX-7's aren't suposed to be drag cars or something. Kinda lost me on that one too.
Eh, it was a stretch, but I have NO doubt that I will get shit from more than 1 RX7 "enthusiast" for primarily setting my car up for drag racing. Especially with the Panas, which I LOVE - and they happen to be the perfect size and fit for the DRAG tires I want to run (even if they are typically "road race" rims.)

"You'll ruin everything with the V8!! WHY??? RX7's are supposed to have rotories!"
"You'll be an idiot if you drag race!! WHY??? RX7's are supposed to be corner-carvers!"
blah.
I suppose if I cared, I would just give them my cars to modify. Til I become that stupid, I'll have fun doing what I want.

As far as the BFG's go - I have plenty of experience with DR's from my Stang days. I prefer the stickiness of the BFG's, even though they don't last at all. Oh well. I'm willing to sacrifice tire life for some semblance of traction. My Stang actually handled much better with the DR's on than any other tire I had - even in the corners (when aired up a bit).

'85 GSL 302 07-04-03 09:18 AM

Cool, I may stuff some DR's on the back then and hope for some decent traction then. How big do you think you can go? It seems to me that you could probably fit a 225 under the car with some close tolerances, but I really don't feel like putting up with any rubbing so I'll just take others words for it.

fatboy7 07-04-03 11:14 AM

225's should fit no problem, I know several on this board who run them.... 235's might even be a possiblity IIRC.

I have no problem with drag racers.... there isn't a road course within 400 mi from here, so everyone hear builds their cars to at least go somewhat fast in a strait line, even if thats not there main focus.

DR's handle OK enough on the street, even in the twisties. Don't expect them to handle so well on a road course, I have an acquaintance that tried that on a track day..... Man was he all over the place, not to mention that it ruined the practically new tires.

wagondriver69 07-04-03 11:57 AM

Im disgruntled........Mostly because of the poor quality of the egg mcmuffin I had for breakfast....However that 302 swap is looking good! I got a 302 in my wagon, a full size grand marquis, and it pulls along great. Id imagine after mods and in a 7 it would be sweet too. Good luck

:peace:

Cloud 07-04-03 01:16 PM

One guy I know has 225/50/15 BFG DR's on his car, runs mid 11's...no rubbing that I know of...

Another has 235/60/15 on his car, runs mid 11's...but not so sure about the rubbing on that one.

'85 GSL 302 07-04-03 11:53 PM

Cool. I might go pick up a set of 225 555's for the car sometime soon. We'll see how my finances look after the full exhaust and drifeshaft are paid for. Thanks for the help guys. I'll let you know when it's running. Expect some videos. I like videos.... I have some crazy stunts in the Prelude that I have to top in my new car.

Fennix_sr 07-05-03 12:21 AM

can anyone post some vid's of v8 1st gens? , oh and thats lookin like a beauty of a swap, im thinkin about going V8 but im addicted to rotaries...

MarkPerez 07-05-03 01:11 AM

The tigers were awsome cars, for a minute. you know the early (roots) tigers came with a 260 cid, and in '67
they got the full blown 271,hp 289 hi-po. a 'k' engine
you know,with the counter weight ? fast little cars just ask maxwell smart,, Lol anyway, what kind of pan is that ? capicitys ? and why roller rockers, with no roller bump stick ? on the harmonic damp'ner. how heavy ?
liquid filled ? the mounts you made look real good.
do you know what the size of valves are installed in those (smog) heads ? loose the spacer plate and work that holley over. how much more would you have had
to pound the firewall in, for the shifter to be placed right in the middle of the tunnel/shifter opening ? I'm hoping that before you put the engine together you had all the pieces including the clutch,,balanced. you might as well add an oil cooler on to the remote (transdapt) filter(ph8a)... My self, i got a thing for 1969 1/2 Boss 302's
both cars and engines, just something about them.

Chrisman1969 07-06-03 07:36 PM

Nice work.

My 302 conversion weighs in at 2600lbs and dyno's 307 RWHP.

http://www.jickedoutbastards.com/1002.jpg

It is the funest car that I've ever owned. It gets more positive comments when I take it to track events then the other exotics there.. and I am dead even with a 2003 Cobra Mustang from a 45 roll - through 110.(I run out of gear).

Here is some stuff on my conversion.

www.jickedoutbastards.com/rx7.html

Good luck

'85 GSL 302 07-06-03 10:50 PM

Hows the suspension working out for you? How's the car's balance and handling? What do you have to say to all the people that say the handling will be way off because of the balance. I'm curious myself.

'85 GSL 302 07-06-03 10:52 PM

Oh yeah, and was your fuel tank full with that weight?


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