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SVT Squasher 12-31-03 03:54 PM

Considering V8 convertion
 
Well I am thinking about a V8 convertion. After putting new turbos on my FD and 755 miles later I have a huge coolent leak and think that it is going to be real bad news. The orig motor was replaced at 50k and this motor has 18k on it and I dont think I realy want to keep spending $$$$ on unpredictable reliabilaty.

Depending on cost between another rebuild and a V8 swap will prob be the final factor.

What I am looking for is info on doing the swap.

1) Where can I find motor mounts or will I have to fab them my self? If I can buy them, how much?

2) Has any one done a 4.6 SVT motor swap? I would like to do some different from a sbc if possable and I have had good luck with the 5.0 I put in my Jeep.

3) What other things need to be swaped besides the motor?

4) What is done about the insturment panel and the ECU? How do you intergrate the two or the panel to a new ECU?

5) How much clearance is there one the 1.3 is pulled out along with the inercooler? What V8 fits the best?

6) About how much can I expect to spend minus the cost of the motor and tranny?

7) Does sombody make a convertion kit?

I am not wanting to build a Jimlab project with 650+ hp but would like to have a nice 400 hp with nice lbft. I am very mechnical and have a lot of the tools to do the job. I even have the tools to fabricate if I need to and can do a nice job also, but if there are mounts out there that would be even better so I dont have to worry about the placement of the motor along with the hight.

These are just ?s that I have that will help me decide the fate of my FD.:confused:

paw140 01-01-04 09:32 AM

Check out www.hinsonsupercars.com. That site will answer most of your questions. Also go to www.torquecenteral.com and read the V8 RX7 forum.

TOUGHGUY 01-01-04 12:32 PM

A rebuild on the rotary will cost less. That is not the point of the swap though. How much have you spent on motor work and how much are you willing to spend in the future to achieve the performance level you want? In the long run, a piston engine will cost less to operate because it will be more reliable AND if something goes wrong, parts are cheaper.

Forget the Ford mod motor (4.6) it just won't fit! A 5.0 is possible but is not as popular as the LS1 chevy engine. True you can build two 5.0s of the same power as one LS1 but that's just because the LS1 is a newer engine. In a few years, parts prices will drop like they always do.

So much talk about FDs hanging with Z06 vettes going around to make your head spin. Truth is, a stock FD will NOT hang with a stock Z06. Modded FDs that can hang with one are relatively abundant but mucho dinero has been spent to get it that fast. A Corvette engine in a car that is several hundred pounds lighter will not only cost you less but will also be faster than a stock Vette. An LS1 conversion will cost you about $3000 plus the cost of the motor. Some will say it can cost less and I believe in can but there is always the personal preferences and the nickel & dime stuff that add up.

PAW140 has already posted the two most relevant resources so you should check them out.

Toughguy :)

SVT Squasher 01-01-04 05:03 PM

Thanks for the feed back I checked those sites out and I am very impressed. That is a very clean swap. I belive at this point I will do the convertion even though it might cost more $ than a rebuild. Looking at cost right now with a rebuild on the rotory at $3500 and then I need to get a PFC $1200, that right there is $4700 and the reliability is a still a factor. After reading the thread in the arcives "You know your an RX-7 owner if:" explains why the convertion is a good thing.

It was also a determining factor that Granyspeedshop is in Concrete WA. about a 45 min drive from my house. and they only want $1500 for the subframe, tranny mount and tourqe brace. So with the LS1 $2000 and the T56 $2000 (I am sure I might be able to find them for less) thats only $5500. I know I will have other cost to incure like a pedal assembly and a cluch master cylinder, speedo calibrater and othe little stuff. Im figuring that the total cost might be around $7000. The differance is $2300 which is a small price to pay for the peice of mind, 315 hp(stock LS1), no more vac nightmare, bottem end torque, I can go on and on about the advantages that will make it worth it.

I feel this is probably the best thing I can do for my FD.......

turbogarrett 01-02-04 08:49 AM

have someone with a ls1/t56 swap give you a ride, you'll be sold on it! also i see you have an auto which has the more desirable for the v8, 3.90 rear end.

wingsfan 01-02-04 09:52 AM


Originally posted by SVT Squasher
Thanks for the feed back I checked those sites out and I am very impressed. That is a very clean swap. I belive at this point I will do the convertion even though it might cost more $ than a rebuild. Looking at cost right now with a rebuild on the rotory at $3500 and then I need to get a PFC $1200, that right there is $4700 and the reliability is a still a factor. After reading the thread in the arcives "You know your an RX-7 owner if:" explains why the convertion is a good thing.

It was also a determining factor that Granyspeedshop is in Concrete WA. about a 45 min drive from my house. and they only want $1500 for the subframe, tranny mount and tourqe brace. So with the LS1 $2000 and the T56 $2000 (I am sure I might be able to find them for less) thats only $5500. I know I will have other cost to incure like a pedal assembly and a cluch master cylinder, speedo calibrater and othe little stuff. Im figuring that the total cost might be around $7000. The differance is $2300 which is a small price to pay for the peice of mind, 315 hp(stock LS1), no more vac nightmare, bottem end torque, I can go on and on about the advantages that will make it worth it.

I feel this is probably the best thing I can do for my FD.......

Not to rain on your parade, but before you give Grant any of your money, you should do two things. The first is realise that he has yet to deliver a cradle that works for the LS1 to anyone (even his lt1 cradles are questionable), and the second is search around and see some opinions of his work. I've never used the guy for anything (and likely never will), but several people who have are extremely unhappy with his work (or lack thereof in some cases).

Anyhow, if you want to go the LS1 route, go with Hinson's setup. It's a no brainer. The parts are top notch and they will save you all the trouble of fabricating your own (meaning the measurements are already made and they are rproven to work).

I got my conversion parts from Bryan and got my car back on the road in 4 months total. Also, when figuring out your expenses and whatnot, make sure you buy the engine and tranny as a pair. Nothing sucks worse than trying to track down some little piece that you'll need to get things to work. If you want an idea of what I spent on my car check out this thread here:

http://www.torquecentral.com/showthread.php?t=18372

I went a little nuts, and I blew my initial budget out of the water, but considering I didn't have most of the tools I needed, or raw materials (I made most everything but the big conversion pieces myself), and that I upgraded a lot of suspension pieces along the way I think I did pretty good.

Do a little more research before you make the decision. Not to be a dick or anything, but two things jump out at me that suggest you should read some more before you make a decision. The first being the crap about Granny's (disgruntled customers and the lack of a functional ls1 cradle), and the buying the new engine/tranny as separate pieces. There's a wealth of info over at torquecentral, and plenty of people that have "been through the fire" so to speak. Take advantage of that.

People make it sound like It's no big deal to cvhange out the drivetrain. Like it's changing a tire or soemthing. It's A lot of work, and you'll lhave to come up with some creative solutions here and there.

OK I'm off my soapbox. That said, I'm up in Seattle from time to time in the summer months, so if you ever want to go for a ride, or just check a conversion out let me know and we might arrange a meeting.

Andrew

TOUGHGUY 01-02-04 02:07 PM

I'm with Andrew on this one. Although I have never dealt with Granny's, the horror stories I came across were enough for me to cringe whenever he was mentioned. And even though most everybody who has purchased his 1st gen swap hardware never had a problem, I purchased my mounts from another member on the board at Torquecentral. When I got them I made blueprints and posted them for free just so nobody would have to deal with Granny's if they didn't want to.

Also like Andrew says, mix-n-matching from different sources is doing it the hard way. Find a complete wreck with everything and go from there. Check these on Ebay:

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2451496137

Or if you just want the engine and tranny without the hassle of parting out a complete car,
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2450977486
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2451262693

Now these are 2000 models and if you read up at torquecentral you will see that 2001 and up is recommended. I don't have all that info of hand so do some more research before you buy anything.

Toughguy :)

SVT Squasher 01-04-04 10:40 PM

Hey thanks again for the replies. Thas some good advise there Wingsfan. I was going to try to get out to Grannys on monday to take a look at there product. The concern I have with theirs is the 100 thousandth of a inch clearance, I would like a little more if at all possible. I havent found out yet if the LS! intake sits lower than the LT1 yet. I hope it does I like the idea of a newer model motor.

Monday I will check out Granneys. I do like the Hinson though it seems pretty stright forward and I like the wiring harness that they have. They dont tell you what kind of clearance they have, is this becuse its not a n issue?

wingsfan 01-05-04 01:13 AM

Well, the LS1 is a full inch taller than the lt1, so a cradle with only thousnads clearance for an lt1 isn't going to work (not to mention that they have a different motor mount setup). Like I said before, Grant has not to my knowledge delivered an ls1 subframe to anyone. I know of a few people who are not happy with the lt1 subframes they got from him.

So far as I know for an LS1 conversion your choices are go with Hnson's setup or make your own. I went with Hinson's because it was easier and saved me a lot of work.

My understanding is that Hinson's wiring harness is just the stock LS1 wiring harness with things labeled and the unnecessary wires removed. I modified my ls1 harness myself, so I can't speak to the quality (or lack thereof) of the harness that Brian is offering).

And finally, clearance is not an issue with the ls1 and the Hinson setup. My hood closes just fine, and I even have an R1 strut tower brace on the car. you do have to lower the steering rack and then correct the bump steer with adjustable tie rod ends.

wingsfan 01-05-04 01:17 AM

Oh, and good luck checking out Granny's. From what I understand he doesn't answer the phone very often, so I wouldn't be at all surprised to learn that he's not at his shop either. I don;t have anything against the man personally, but I've seen enough people complain and heard enough horror stories to know that I'd steer clear of him.

SVT Squasher 01-05-04 12:48 PM

I hear you. I tried to call them this morning and the first # was dissconnected and the second there was no answer I guess they are to proffessional to be at there shop. I kind of figured they are a small ma and pa shop since they are in Concret total population of maybe 500.

I looked at your thread Wingsfan on cost of the convertion and I had a few questions for you.

wingsfan 01-05-04 02:54 PM

Fire away with the questions. i'm more than happy to answer the ones I can. You can always pm me or send me an email if you want.

SVT Squasher 01-05-04 11:28 PM

I will shoot the questions thru the thread so if anyone dose a search they can find them if you dont mind. I did a search and had a hard time finding anything on the convertion.

My questions are;

1) Is the Hinson subframe a bolt in or a weld in?

2) What sensors are requierd for the LT1/LS1? I know the FD oil level sensor will have to be moved over to the new motor but what is requierd from the doner car?

3) How is the steering rack lowerd and dose this effect the ride hight? I was wandering becuse my car is lowered.

4) Is a new fuel pump need? I thought the stock fuel pump was a 255iph already, so is another one needed or do you need like a pull type fuel pump?

5) Whould you recomend the Hinson wiring harness even though its the stock harness just cleaned up? I know the 5.0 that i put in my CJ7 the harnes was a nightmare and I would like to make the convertion as clean as I can to try to make it look like its a factory install.

6) Is there some modifying the oil pan with the Hinson setup?

7) Is there anything that you can think of that is out of the ordinary that I might need to do the convertion becuse I have the automatic besides the pedal assembly? Not including the clutch master cylinder becuse I would need a larger one anyway. Dose the T56 have a slave cylinder or a hydrolic throw out barring?

8) I noticed that you went with a larger fuel rail and fittings and different fuel pressure regulator. Why? Was the ones on the motor not adiqueit?

Here are the questions that I have on the top of my head for starters. Some of them might seem dumb but I like to know as much as possible before I start the convertion. I realy appreciate all the help.

Thanks
SVT

wingsfan 01-06-04 01:29 AM

First off, just to clarify. Hinson doesn't sell an LT-1 subframe, so to get one you'd have to go through Granny's, Jimlab (I don;t think he wants that headache), or some other source).

Anyhow, on to the novel.


Originally posted by SVT Squasher
I will shoot the questions thru the thread so if anyone dose a search they can find them if you dont mind. I did a search and had a hard time finding anything on the convertion.

My questions are;

1) Is the Hinson subframe a bolt in or a weld in?

It's a bolt in subframe. It uses the existing RX-7 subframe mounting points and allows you to keep the stock suspension/adjustable alignment. It's literally plug and play, with the catch being you have to mail them your subframe to have Lane Culver modify it for you.

Hinson is the frontman, Lane is the fabricator. He does excellent work, and the both of them are really pleasant to work with. I got my stuff in a reasonalbe amount of time, and I had no problems. I'd do it again in a heartbeat.



2) What sensors are requierd for the LT1/LS1? I know the FD oil level sensor will have to be moved over to the new motor but what is requierd from the doner car?

The sensors you keep are all dependent on what gauges you want to keep. I'll be replacing my water temp and oil pressure gauges, so I didn't bother keeping them. I'm not sure how you'd even go about keeping them, bu my guess would me your best bet is to use the LS1/Lt1 senders and figure out how to adapt the gauge. I know that you can modify the LS1 oil level sensor to work with the RX-7 gauge. other than that, the LS1 pcm and engine combination has all of the sensors that it needs to run. The PCM is pretty much the equivalent of a standalone fuel management system for many other cars (especially if you own ls1edit, which I do).


3) How is the steering rack lowerd and dose this effect the ride hight? I was wandering becuse my car is lowered.

The steering rack is simply lowered. The steering rack isn't supported by anything once you remove the subframe, so it's free to move up or down (to a degree). The mounting point on the new subframe is lower than the stock point, so in order to bolt the steering rack to the subframe it ends up lowered. Lowering it creates a bump steer situation that you need to correct with new tie rod ends (adjustable height) that Hinson sells as part of the kit. they're mandatory, as in you HAVE to use them, no ifs ands, or buts.

Lowering the steering rack shouldn't have any effect on your ride height as that will ultimately be controlled through your coilover. The rack only drops around 0.5"-0.75" so it's pretty minimal.


4) Is a new fuel pump need? I thought the stock fuel pump was a 255iph already, so is another one needed or do you need like a pull type fuel pump?
I'm not sure what the answer to this is. I went ahead and replaced my stock pump with a high pressure Walbro 255lph pump that I got from an ls1 specific store.

You'll know immediately if your pump is not up to the task as the LS1 requires a higher fuel pressure than the Mazda system can deliver by itself (58psi v. stockwhich is around 44psi IIRC). You will need to run a fuel pressure reglator in your setup to control the pressure.

You definately want to run an intank pump of some sort. The Walbro is cheap and easy. I had to make a fuel line running from the pump to the sender, but if you buy the RX-7 specific pump it should bolt right up.


5) Whould you recomend the Hinson wiring harness even though its the stock harness just cleaned up? I know the 5.0 that i put in my CJ7 the harnes was a nightmare and I would like to make the convertion as clean as I can to try to make it look like its a factory install.
That would depend on your budget and your comfort with wiring. For me I wasn't willing to spend $400+ to have someone clean up the harness for me, and I wanted the experience of doing everyting (or most everything) myself. So I did the wiring myself.

It wasn;t difficult as I had access to good wiring diagrams, good pinouts, and enough people have done the swap that if I got stuck (I didn't really) I could ask over at Torquecentral. The drawback is that I have A LOT of unnecessary wiring in my setup, so it's not as neat or light as it could be (you'd be surprised how much wire can weigh).

My install is pretty clean. you'd have to look hard to see that it didn;t come from the factory the way it is. Black electrical tape hides a lot of sins. :D



6) Is there some modifying the oil pan with the Hinson setup?

Not if you get an engine out of an F-body. You HAVE to use an F-body pan (even if you get a Vette engine). The "wings" on the vette oilpan are too wide. buy your engine out of a ws6 or a Z28 and it's no big deal.



7) Is there anything that you can think of that is out of the ordinary that I might need to do the convertion becuse I have the automatic besides the pedal assembly? Not including the clutch master cylinder becuse I would need a larger one anyway. Dose the T56 have a slave cylinder or a hydrolic throw out barring?

There's lots of things out of the ordinary that you'll end up needing. I can't think of everything off the top of my head, but your best bet is to go ahead and budget for a few extra things and then hope you don;t need them later. It seems like there were a million little ticky tack things that kept bogging me down. I had to go buy a tool here, or a bolt and washer there, or get my cylinders filled because I was out of acetylene, etc. It happens, so you just have to deal with it. I'm sure some other people are more resourceful than I am, but I never met a good tool that i didn;t want to buy :D

I used my rx-7 pedal assembly. Obviously you're missing the clutch pedal. you could either adapt the f-body pedals (I have a set that I didn't use that came with my engine if you're interested), or find a set of FD pedals out of a wreck.

For the clutch master cylinder I used a Wilwood universal 7/8" master and gave it it's own fluid reservoir (the FD shared it's clutch reservoir with the brake master). It's about $75 at Summit

T56 from an LT-1 is going to use a slave cylinder. From an LS1 they're hydraulic throwout bearings. You'll have to adapt the clutch line from your master to the tranny. Mine wasn't quite long enough for the routing I wanted to use.


8) I noticed that you went with a larger fuel rail and fittings and different fuel pressure regulator. Why? Was the ones on the motor not adiqueit?
I didn't go with a larger fuel rail, so I'm not sure where you got thatfrom. I did go with stainless bradied lines from the RX-7 hardlines, and you do have to use some sort of FPR to get the increased pressure that I mentioned above.

Other than that I used the stock LS1 fuelinjectors and the rail. I don't think you need to increase the fuel rail for quite awhile, and you don't really need bigger injectors until you do a heads and cam swap (I'll be starting my camshaft swap next week).



Here are the questions that I have on the top of my head for starters. Some of them might seem dumb but I like to know as much as possible before I start the convertion. I realy appreciate all the help.

Thanks
SVT

No need to apologize for asking questions. i don't mind taking the time to answer them when I can. There's so much misinformation floating around taht it's good to get things from somone who's done it. I got tons of help from Irondonut and 1point3liter, and a handfull of others over at Torquecentral, so I'm merely passing on the good deeds.

Anyhow I hope that helps.

Andrew

jimlab 01-06-04 03:21 AM


Originally posted by wingsfan
First off, just to clarify. Hinson doesn't sell an LT-1 subframe, so to get one you'd have to go through Granny's, Jimlab (I don;t think he wants that headache), or some other source).
As far as I know, I'm the only source for an LT1 cradle for the FD that works and has proper clearances. To my knowledge, Grant still hasn't built a cradle for the FD that works properly with either engine.

Read the sticky post at the top of this forum for my experience with Grant/Granny's and why I eventually had to have my own cradle built after an incredible waste of time.

SVT Squasher 01-06-04 01:28 PM

Hey guys Thanks alot for the info I am sure I will have more questions later.

I have decided to go with the Hinson kit and I have found a LS1 with 60k on it for $2100, they dont have the T56 in thou and they want $1900 for it. I think I might hold off for a bit and see if I can find a complet rebuildable car for the doner when my budget can afford it .

I havent had a chance to cheack my coolent leak on the 1.3 yet and even if its nothing big the LS1 swap is still a go, it is inevitable at this point.

Thanks again Wingsfan for all the info. Im not sure where I thought you went with a larger fuel rail tho. Anyway Thanks again.

SVT


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