1986 RX-7 + LS1= Happiness
 

I recently found a 1986 RX-7 that I'm considering buying for around $600. It needs serious engine work (think rebuild) so instead of repairing/replacing the original motor, I want to drop on LS1 in it. A friend and I would handle the swap ourselves. What I would like to know is this: 1. Roughly how much am I looking at spending on this project? 2. How reliable would it be as a DD? 3. How much work is it? Is it pretty straight forward or does it require a lot of cutting/welding/etc?


If I think of anymore questions, I'll post them up. Thanks in advance.

It will cost around 10000 to do the swap well. I say well because you could get away with doing it cheap for probably around 8500, but it wouldn't be very pretty. Realistically 5000 for the motor and trans, 1600 for the swap materials, 350 for the fuel system, 650 for the coolant system, and then other misc. costs that go up as the quality of your swap goes up. There is usually no welding, but there is a small amount of cutting. The swap has some "handy-man" fabrications involved, but like I said no welding. If you take your time with the swap and make sure everything is neat reliability is good. If you just blindly toss in the motor and hood shit up until it works there will be some bugs that are just frustrating. If you take your time and really clean and organize everything the swap is not only more reliable and nicer looking, but you learn a massive amount about your car and become a better mechanic. In the end, it's definetely not cheap, and definitely takes a decent amount of time to be done right.

It'll cost 10K dollars for the swap if you buy everything retail and add extras.

There are many threads about this.

3500-4000 for engine, ~2500 for everything else will about cover a stock swap if you're doing it yourself. If you want to start going to braided hoses, long tubes, cam, etc, obviously the price goes up.

So, 6000-7000 dollars, and you're done. You can, of course, spend more.

Not in an FC, it won't.

1. The FC engine mounts and transmission mount are relatively cheap, and after buying an LS1/T56 combo for about $2,500-3,000, hopefully with a harness and PCM, the rest is nickle and dime stuff to finish. For a stock LS1, it's unlikely you'd have to upgrade the fuel system or cooling system, although it's not a bad idea to replace the stock fuel pump with a Walbro for about $120, especially with a high mileage car or one that has sat for awhile (check the tank for rust). You will have to find a shop to modify the driveline, if you don't buy one with your kit.

The entire swap can probably be done for about $5,000-6,000 total, including the drivetrain, depending largely on how much of the work you can do yourself, what kind of bargains you find, and how many OEM parts you can sell to recover costs.

The reason most FD swaps cost in the $10k range is because A) the conversion parts are more expensive, B) most are adding long tube headers, intakes, cylinder heads, cam swaps, and a dozen other things that add to the cost of the conversion, and C) FD owners are typically far more concerned with appearances under the hood.

2. How reliable? Extremely, assuming you're capable of wiring correctly.

3. A bit, but nothing someone familiar with cars and having a decent set of tools can't accomplish.

My advice is to visit www.torquecentral.com and check the V8 RX-7 section. Most of the members are idiots, assholes, or both, but there's a lot of good information there posted by a few sensible people, and an LS1 into an FC is probably the most common swap, arguably.

Of the two, Grant Robbins (Granny's Speed Shop) is probably the lesser of two evils for swap parts, when you consider Brian Hinson's track record with quality issues. Grant will probably only lie to you about when your parts have shipped. :)

http://members.tripod.com/~grannys/2...x7chevyv8.html

http://www.hinsonsupercars.com/parts...gEquipment.htm

I have an LS1 FC and can vouch for "it can be done with $6000" prettymuch... until you start upgrading suspension, wheels, interior, etc. but just about 6 grand will get you up and running and if your FC was in good shape before then you are ready to rock. there are a lot of ways to save money too, search for topics and you'll find some good ideas like using a corvette fuel filter that has a FPR incorporated into it, using Fbody radiator /fans /relays, using an older corvette driveshaft with new ends or a Fbody steel driveshaft (find them for almost free) and shorten it +the proper end flange from Grannys, have the computer (pcm) tuned by a place like jesseebub, do the wiring harness cleanup (mod) yourself, etc etc.

I have a lot of good pics on my homepage (see sig) from my buildup and how it all went together including stuff like reinforcing the rear diff mount on the subframe. EyeOutThere from torquecentral made his own mounts based on what he saw me get from Hinson, you can find his posts and he has info on how to make your own mounts, its pretty simple stuff compared to FD mount setups.

good luck on the swap if you go thru with it! :)

What are some other V8 engines that swap in well?

SBC 350/5.7L, SBF 302/5.0L.

If you can fabricate a mounting kit, the buick 3800 SII, (or older 3.8 turbo) are both very capable engines, if a little more involved then SBF/SBC/LSx stuff.

Ok, what about speed? That's the whole point in doing the swap. What's the top speed like, how fast does it accelerate, stuff like that.

EDIT: Also, what about the suspension and weight difference? Is the stock supspension enough to handle it until I can get the cash to upgrade it too. What the difference in the between one with a stock engine and one with a LS1/V8?

Top speed- faster than most people will ever go on the street.
1/4 mile- low 12's seem pretty common for mostly stock LS1 swaps.

Stock suspension is fine, almost no weight difference.

About 2.5-3 sec in the 1/4

check out http://grannysspeedshop.com/ ... they will give you mostly everything you need besides the engine if your looking at a ford or chevy swap. I think they have some things on LS1's too.

*Sorry, I meant to say what is the difference in the weight between one with a stock engine and one with a LS1/V8?

about 100 pounds, most of which is still centered in the car's center section thanks to the low placement of the tranny, which with the LS1 swaps is a huge part of the weight gain.

you can eaisly reach 160mph+ with any properly running SBC/SBF/LT1/LS6 swap but I wouldnt go over 100mph on any stock FC suspension thats for sure.

the LT1 is a good way to get a 6speed V8 into an FC on the cheap.

How much would a LT1 cost? Roughly

I think you should research some before you ask every question possible


I think the ford 2300 turbo is the best engine, but thats just me...

If you like not having any low end torque to speak of, sure.

About $1,000 less than an LS1, give or take.

I think we need to start a support group for you guys, you can share a room with the rotary guys.

You have driven a "600 HP 2.3L Ford" right...?

the only time i saw that engine in an FC it didnt fit under the hood. to me thats a bad option.

The only time I saw that engine installed in an FC, it didn't run, and was then parted...

It's funny that it's primary backers are this guy, the guy building a 'Vert dragster that will do wheelies with a 383, and Nihilanthic... LOL

What do you expect? He's been feeding off Nihilanthic's 2.3T mania for months over at Torque Central. :D

http://www.torquecentral.com/showthr...4&page=1&pp=25

Among other gems in that thread, Nihil claims to have had a project car, but it was towed :rolleyes:, and photopaintball says he's going to get an NA engine running first, but "will go all out really soon". Guess that means that 600 horsepower on pump gas is right around the corner.

Meanwhile, it appears that he's breaking new ground by using PVC pipe to construct an ultralight hood frame. :bigthumb:

http://www.photopaintball.com/car/1.jpg

http://www.photopaintball.com/car/2.jpg

Priceless. Frankly, I'm surprised that's not a gate latch. :rlaugh:

Jim,

This doesn't happen to me often, but, I'm really speechless.

Just... wow.

:rlaugh:

oh yeah, that too.

wow. amazing hood.

i hope the plan was to finish it with a sheet of plexiglass. maybe glue some bass boat glitter to it?

FAIL

Clear plexi. Gotta show off that 600 hp pump gas junkyard 4-cylinder... :D

When I see PVC piping and water, I assume irrigation systems. Maybe this is some genius ultra-low-budget water injection setup. :D