Not sure what to think of this.

http://members.tripod.com/~grannys/hagen.html


http://members.tripod.com/~grannys/3...x7chevyv8.html

 

has it been one month yet?

 

not that anyone cares but i'll tell you someone spent way too much time/money to turn a fd into a ill handling ....

 

Good god, here we go again.... What happen to that thread?

 

NO way!.... he's in AZ?! Hmmmmmmmmmmm sounds like I'll have to get ahold of his e-mail... I'd like to see that!

 

I bought my FD because of its performance potential that included a rotary motor. I dont give a **** if i have to put 100 13BREW engines in my car during my ownership period. And for those who read this and think of doing this thats your option but i cannot imagine what kind of problems with stressing the overall chassie of the car with the amount of torque rocking back and forth on it. Think about it!! I bet any amount of money that the owner gets rid of that car within a few months due to the problems associated with that conversion. You people on the forum can do what you like, this is America i just cant see the point.

 

How much $$ did this guy spend again to pull a 13.5?

 

Yeah thats what I ws wondering.

 

Here it is:

https://www.rx7club.com/vforums/show...threadid=20343

Everytime this is brought up, refer them to this thread, cause the same arguments for both sides gets rehashed over and over and over and over....

 

So why is it that we see all these bastard child V8 conversions but never the other way around?

How many C5's, Camaro's, Mustangs have you guys seen with a wankel in them?

 

How many wankels can produce sufficient torque to power a 3500+ lb. car off the line quickly?

 

Come on Flybye, you should know better than to say something like that. It's a stock engine. What do you expect. Now what if he put a 200 shot of NOS which it can handle? You're talking an extra $800 and it'll be in the low 11's. It's not how much money he put into it, it's the potential. My $0.02

 

Dude, the guy asked how much it cost him, not how much more it will cost to make it faster. I am also very curious to see how much it cost him. Do you know? Does anyone know? Of course that link that told you all about his car, but not how much it cost to do what he did. I am not against putting a V8 in an RX, but how much did it cost him to make the car .5 seconds faster in the 1/4 mile?


Petros

 

Sorry, his statement just seems like he's saying that Bill spent so much money and only took off .5 sec. I reality he could do alot to his engine for very little money. I don't think Bill spent too much on his conversion. You can see that he kept his conversion as stock and emissions compliant as possible. I don't know the exact amount but I'd say he spent anywhere from $2500-$3500. I'm building mine up to hopefully 700hp on NOS. My total of course will be way higher than Bills but when I start to drag race again, I'll know where all that money went to

 

If you think that "all" he gained was .5 seconds in the quarter, then you stopped your thought process too soon.

That run was on Bill's first (and only, as far as I know) trip to the track. The Gen II LT1 engine was capable of 13.5-13.7 quarters in a Corvette with a minimum curb weight of 3,300 lbs., not including driver, so his RX-7 is absolutely capable of lower 13s or possibly high 12s. Bill's performance was traction and experience limited. I've seen 300-320 RWHP FDs fail to break 13.6, and I've seen a single turbo FD run a 13.1. Quarter mile performance is not as simple as bolting on some horsepower and pushing the pedal while holding the wheel straight. If you think it is, you should try it some time. Tell us how well you do on your first outing.

Second, he vastly improved the reliability of his car. He now has an engine that can and probably will go 200k+ miles before it requires a rebuild. He'll never have to worry about whether or not his second turbo comes online. He'll never have to worry about boost spikes. Or bad gas. Or vacuum line problems. Or overheating. And he'll never have to clean "smoot" off the back of his car again. Or worry about tossing an apex seal out through his rear turbo...

Third, he's passed emissions. How many of you with high horsepower FDs can say that? I'll bet that not many of you have kept the stock catalytic converters, or even have a high-flow cat. He has cats, and the stock cast iron exhaust manifolds to go with them. He can also significantly modify his engine without worrying about a smog ticket. Just switching to a set of headers would gain him 30 or more horsepower easily, and he'd still pass emissions.

Fourth, he is at base level as far as modifications go. A cam and a set of ported heads, with a set of roller rockers and a throttle body would put him near 400 RWHP for around $2,500-3,000. He'd still pass emissions, and he still wouldn't have to worry about reliability. You can't even buy a single turbo kit for the FD for that money, and even if you could, you'd still need a fuel computer mod and a number of other supporting modifications to ensure that you didn't pop your motor immediately. For another $250, he can fully tune his computer with laptop, with data logging, and get base maps from 100s of other LT1 owners with the same or similar modifications. What does programmability for the FD cost?

Fifth, his fuel efficiency just doubled, for all intents and purposes. He'll get 25-28 mpg on the highway and 18-20 in town. When was the last time you got better than 15-17 mpg period? It's no Honda, but his car will travel farther on each tank of gas, and it doesn't need to inject oil or have pre-mix added to the tank. He can fill up wherever he wants, and he can even put 87 octane in the car, if he wants, because the computer will back out timing for him. Care to run a tank of 87 octane through your FD?

Sixth, he gained simplicity. He has a very simple system which will respond well to even small modifications. 15-20 horsepower for roller rockers alone. 10-15 horsepower for a larger throttle body. Even larger gains if he ports the heads, which can cost as little as $500 or so up to around $2,900 for a complete set of fully race ported replacement LT4, AFR, or Canfield heads, good for 100 horsepower or more. Many cams to choose from, depending on how much power he wants to make and where, keeping the car emissions legal, and so on. The sky is the limit, because he has a solid base to build from.

Seventh, his transmission strength and reliability is vastly improved. You can't get a stronger production gear box than the Borg Warner/Tremec T56 6-speed. He gained a 6th gear, and the ability to break 200 mph with enough horsepower, if he wanted to. He can powershift without having to worry about breakage, and he'll never have a 5th gear synchro problem.

His handling hasn't been adversely affected. His car is nearly balanced, although with the ballast he added and his cast iron exhaust manifolds and full accessories, he's a little heavier than a touring model. So is a 20B conversion, and they're not 50/50 balanced either, that I've seen proof of. Have Cam Worth put that Banzai on corner scales and let's see the truth about the 20B conversion. I know what my 3-rotor weighed on its pallet, and it was 90 lbs. heavier than a base LT1. Vipers don't have 50/50 balance... are they shoddy performance cars?

There's probably more, but the lesson is almost surely lost on someone who would make a snap judgement about the benefits of a powertrain swap he knows little or nothing about, just because there happens to be a piston engine involved. It may go against the heritage of the car, but you'd have to care more about the car's heritage than you did about reliability, performance, fuel economy, and simplicity, and that's a tall list to overcome just to keep the heritage of the car intact.

As always, it's not for everyone. If you don't agree, that's fine, but at least have a rational excuse for why you don't agree. That it's a piston engine isn't enough. That it's "archaic" technology isn't enough. That you believe it ruins the weight or handling of the car isn't enough. It is a piston engine. It's *proven* and *reliable* technology, and it doesn't "ruin" the weight or handling of the car. And if the swap only netted a .5 second improvement in elapsed time, that'd be just fine, too, since most stock FD owners can't even break out of the 14s.

Bottom line is, Bill is happy with his conversion, and its his car, and that's all that really matters. If you want to be offended on his behalf, that's fine, but I doubt he cares.

 

The ever-articulate jim has spoken....Can't argue with that

 

Right on Jim! I don't think anybody could've put it better than that. Someone needs to save that and put it in a FAQ section or something

 

I still want to know, from someone who knows what they are talking about, HOW MUCH $$$ DOES IT TAKE TO DO THIS!?!? I'm talking parts and labor. Cost of the engine, transmission, installation, how much of a pain in the *** would it be to make your stock gauges work with the new setup, including granny's cost for their custom subframe, etc... So the engine puts out 315 HP, that is respectable. How much heavier will the car be? Bill said he was at 3000lbs.

The reason I am asking, is that I have a 3rd gen with 78k miles on it and leaky turbos. If the engine goes pop eventually, I want to know what my options will be. I don't want to spend $4000 on a single turbo kit now, only to decide to go with a V8 later.

I don't want a ballpark $2,500 to $3,000 "guess". Granny's wants $1,500 for their custom parts. So I can buy an engine and a transmission and get all this installed for another $1,500??? I doubt it.

Anyone want to part with this "classified" information? I can research the cost of an engine and transmission myself, but you don't really know how much something will cost you, until you actually do it.

Thank You,

Petros

 

If you have the space, tools, and time, you can do it like Bill did, I believe, and buy a wrecked F-body (Camaro/Firebird) or Y-body (Corvette) to cannibalize for 85-90% of the parts you'll need. Wrecked F-body cars from '93 to '97 can be had for $1,000-1,500 at auction on an almost steady basis. Anything but a front collision that has reached the engine is probably going to have a salvageable drivetrain in it. The alternative is to watch eBay for LT1/T56 auctions (fairly frequent) or put an WTB ad on www.camaroz28.com and see what comes back.

Separately, you can buy (like I did) a low mile T56 for about $1,000-1,500. It cost $80 to ship from Maryland, but that was before the gas surcharges started to appear. Shipping weight is just about 122 lbs. The OEM 5-speed is 112 lbs. dry, by the way. Stay away from the '93 T56, the transmission was new and had different ratios, and significantly lower power handling (350 ft. lbs. vs. 450 ft. lbs., but that's for 24 hours *continuously*. The T56 will handle up to around 800-900 horsepower). The Corvette LT1 transmission is not a BW T56, BTW, and they are significantly rarer and more expensive, but without any real additional benefit.

T56 compared to OEM 5-speed...


You can find used Gen II LT1 ('92-'97, '92 was Corvette only) engines minus a transmission for very reasonable prices. There was one guy with an on-going auction on eBay awhile back who was selling them for $700-900 used. $1,500 is probably average, so expect to pay around $2,500 for your engine and transmission if you buy them separated from a car, whether or not they're attached to each other. Your setup should also include the computer, engine harness, and probably all the accessories you want at that price.

The '92-'93 LT1s were speed density (MAP-based) only, which requires chip reprogramming like the FD, '94-'95 are OBD-I with MAF and MAP sensors, and do not require recalibration for many mods because they self-adjust like the Supra and can be cheaply programmed with a laptop and software (www.carputing.com), and '96-'97 motors were OBD-II, and are not as desirable, although you can convert them to OBD-I or reprogram them with software now, also.

As stated, the Granny's kit pieces which were developed by Grant and myself sell for $1,700 (I am not involved with Granny's, I was merely the first to conceive the conversion and helped to develop the parts). Bill only used the engine subframe, since the rest of the kit was not available at that point, and modified his own driveline (relatively inexpensive... $75 or so?) and PPF, and created his own transmission brace. All relatively inexpensive and easy for someone with the right tools and time on their hands. Price goes up, obviously, if you have to have someone else do it for you. The Granny's kit is a bargain for $1,700, which includes the engine cradle (lighter than OEM), transmission brace, torque arm, and torque arm bracket, as well as a driveshaft, I believe. Compare that to Pettit's 20B conversion cradle at $2,100.

The majority of the cost will not come from a few hoses for connecting to your radiator and heater core, or for modifying the alternator mount for reverse mounting (as Bill did) or finding a low mount bracket. It will come from having to have someone else do the work. Any project where the laborer is unfamiliar with the configuration is going to cost more and take more time. It's not a difficult project, and in fact, wiring in the electronics and adapting the tachometer and speedometer output (Dakota Digital SGI-5 "Tach" - $115, SGI-5 speedo - $80) with interface boxes to drive the stock gauges is trivial. The hook-ups for the GM ECM are also simple. The only problem is that there is no complete how-to guide (yet, anyway) which covers all this basic information, although I'm sure there will be eventually. Just wait until Max Cooper does one. His write ups are great.

Can it be done for $5,000 or less? Definitely, especially if you can do some or all of the work yourself. Is it difficult? No, simply time consuming. If you had all the parts available and the free time to do the work, it'd probably take a first-timer perhaps 1.5-2 weeks. If you're good with mechanical and electrical work, have some pals to help guide the engine in, and have all the tools you need at hand, then it can be done in a week, I'd bet. Possibly less. Perhaps the only thing you won't be able to do is tie the exhaust into the RX-7's system, which will require a trip to the muffler shop.

There is no fixed cost because there are so many options, and there's no one who provides a turnkey service. If you had someone to drop it off with, and came back to pick it up, there would be a fixed price. The variances in how much you pay for your engine and transmission, how many tools you already have and how much you can do on your own make estimating a fixed cost difficult. But I think it's fair to say that it can be done for $4,500-5,000 at the outside, or about the cost of a good single turbo kit, if you do the work yourself. Consider, however, that if you have modifications, that you can recover quite a bit of the cost of the conversion by selling their OEM and aftermarket rotary components. If it's something you are leaning toward, then you can also benefit by selling your engine core while its still healthy, an option that some have taken.

Does that answer your question? It'd be nice to have a how-to tutorial online available for people who are serious about learning the costs and process for the conversion, but my conversion shares almost nothing in common with the rest except the pieces Granny's sells, and those are simple bolt-ins. For example, I had my gauges recalibrated, tachometer calibrated for a direct V8 signal, and the speedometer matched to 8,000 ppm @ 60 mph, which is the output of my GM ECM (which is normally 4,000 ppm @ 60 mph). I also had the top speed increased and the gauge appearance cleaned up at the same time. Having a new speedo face printed and matching the lighting and font was expensive, but you could probably just have the gauges recalibrated fairly inexpensively.



There are many other differences, and although I may eventually put together a how-to that does have some bearing on a "standard" conversion, there's enough changed with mine that most of my information on cost is irrelevant. I also have my own facilities, tools, and do my own work. If you're truly interested, contact Bill through Granny's, and I'm sure he'd be more than happy to share details with you that would answer your questions about the cost and process of an average conversion.

 

While I'm on the subject, I'll answer the most commonly asked question after people see my revised gauge cluster...

Yes, my engine will turn 8k rpm. And then some. Ultralight forged bottom end, 38 lb. crankshaft, 505 gram rods, 395 gram JE forged aluminum dry film coated pistons. Oliver billet splayed 4-bolt main caps. Custom cast AFR raised runner reverse coolant flow (standard for Gen II LT1, heads first block second) cylinder heads with 2.10" intake and 1.60" exhaust titainum valves, Comp Cams Pacaloy solid roller springs, Crower stainless shaft mount roller rockers, titanium retainers and locks, as well as a Speed-Pro SEFI-8LO engine management system, and one-off Hogan Racing fabricated sheet metal intake with 1,300 cfm monoblade throttle body...

My bottom end...


Pistons and rods...


Bare heads during baseline flow measurement...


Computer simulation of my 396 with a relatively mild solid roller cam for starters...


We could make a lot more power, but not with as good driveability or on a pump gas diet.

 

~400 lbs/ft torque at 2000 rpm?? good lord.

anyone opposed to this conversion can put that in their rotary pipe and smoke it.

any idea as to when it will be complete?

.. and I thought LesD's LS1 conversion was going to be a monster.

 

We designed the cam profile so that power will just be falling off (~590 horsepower) as I shift at 8k rpm. Obviously the motor still makes good power out to 9,500 rpm (~460hp) but it was designed to operate in the band from 2,000 to 8,000 rpm, roughly. Redline will be set at 9,000 rpm, however, just in case I need a little more headroom.

The torque band is 400 ft. lbs. or more from ~2,000 rpm to nearly ~8,000 rpm. In other words, as much or more torque over that entire 6,000 rpm range as my Z06's LS6 makes at peak. And about 140 more lb. ft. of torque at idle than a stock 13B-REW makes at peak. That's where a stroker motor really shines. My 3.875" crankshaft throw and 4.030" bore result in a nominal 396 cid (395.4) displacement in a small block package.

Keep in mind that this is just a computer simulation based on preliminary head flow numbers. The engine will be completed and dyno tuned in December, I'm told. We're already at 323 cfm on the heads @ 0.700" of lift (intake runner) and they'll be ported further after being returned by Hogan. This is also based on a ported LT4 intake manifold which is still relatively restrictive. The Hogan sheet metal intake will not only perform better, but I gained 1/4" of hood clearance.

 

That is actually much more information than I was asking for, but at least now I know what I would be getting myself into.

I have leaky turbos and if they need repair, I think I will just get a rebuild. I will try to hang on to my engine as long as I can. When and if the time comes (knock on wood) for a rebuild of the engine, I will have to make a decision on what to do with my busted motor. It seems that I could do the work myself and drop a V8 in there for about $1,500 more than it would cost for a rebuild. Of course there is alot more work involved, but I don't mind that.

Thanks Jim


Petros

 

I just spent 6,000 on a engine rebuild and single turbo upgrade.... maybe I should have thought this through?

 

Wow,
If you want to do it right this appears to be it.
I am a car guy first and after reading this thread I think I need a smoke.

Vic