My LS1 Miata build

ls1_miata · 02-20-2008, 05:40 PM

So I decided I was tired of the Flyin' Miata FM2 kit on my miata after about 6 months of ownership and wanted to do a LS1 swap. I don't have the tools at home to do any real fabrication nor the time really. I am a full-time Mechanical Engineering student at Georgia Tech so I opted for Racing Concept's kit which includes everything needed for mounting a LSx and Ford 8.8 diff as well as a custom driveshaft, axles and a few bits here and there to get things like the clutch to work.

I use a 2002 Camaro LS1 and T56 complete with all accessories, wiring and PCM. I got the PCM flashed with a C5 Z06 tune. I use a Ford 8.8 diff with 3.73 gears.

I tore my car apt in October 2007, brought it to the paint shop, ordered the kit, got the car back from paint in the beginning of Feb 2008 (only 3 months behind...) and started the install.

I have made a detailed website with tons of pictures and info so check it out and feel free to tell me what to add. I am not done with the car yet but I update the site with every progress on the car (which only happens on weekends).

My Website: http://home.comcast.net/~npartist/

rao · 02-20-2008, 05:43 PM

Nice! I have thought about putting one of those together.

I'd like some more details about ground clearance. Is it on the road yet?

LS1-450 · 02-20-2008, 06:56 PM

Hi, Welcome to LS1Tech

Are you the guy over on M.net asking about what rear end gear to use in a t-56? I have a lot of experience w/an LSX engine in a Miata. Feel free to ask any questions you like. There are others here as well. Be sure & put a Detroit "True-Trac" differential in that 8.8, it will make a night & day difference in traction. I don't know the "Racing Concepts" kit very well, but be sure & pay close attention to sub-frame re-enforcement, use front & rear anti-sway bars, & front & rear strut tower braces. Big front brakes are a must. Good-luck

ls1_miata · 02-20-2008, 08:29 PM

I'm npartist on m.net. I'm not the one asking about the diff but I have replied in that thread. When you say sub-frame re-enforcement I assume you are talking about the rear sub-frame. The front one is all new. I don't plan on running a rear sway as I always preferred the handling/corner exit without it when I had the turbo setup before. Whats your reasoning for keeping the rear sway? The kit includes frame rail braces and I have a 6-point roll bar and front strut tower brace so I should be ok on stiffness.

I have seen your post on m.net and am curious about the C4 brakes. I read that you machined the rotors, correct? Care to fill me in on what is required to do the swap? I plan on getting a True-Trac sometime, right now I am focused on getting the car driving. Thanks for the help.

LS1-450 · 02-20-2008, 09:24 PM

I mean frame rail braces, rear anti-sway, strut tower bracing help against twisting from the torque of the motor. I have a Hard Dog & have never heard of a 6 point. It does bolt in 6 places, but, is considered a 4 point. Unless, there is a new one that I haven't heard of. Usually, 6 point roll bars (cage) includes to locations on the driver & passenger side floors (door hinge pilars) w/ diagonal bracing between the seat & the door, in addition to the standard places. Anyway, it's not important, I just am curious to know if there is now available a 6 point bar.

My point regarding bracing is that a lot of people whom put big torque in little cars can't use all of the power because the body of the car twists from the torque. It's really important to build the suspension & support the unibody first & build from there. Also, later when you add pan hard bars to reduce the wheel hop, the strut & rear anti-sway will re-enforce the area. You can get the rear corner to sit by adjusting the shocks.

To put C4 brakes in a Miata is a pain in the ASS. There are 6 new parts that you need to make (machine) in order to do it. I would recommend using an after market kit for the fronts, 12" rotors either 4 or 6 piston calipers are OK. It's alright to keep the stock Miata rears. I've got my rear brakes dampened so much through a proportional valve, that stockers would have been fine.

ls1_miata · 02-20-2008, 09:45 PM

Its a custom roll bar deal. I wanted as much stiffness/protect I could get without having a bar along the side of my head due to a lot of non-helmeted street driving. Its the rear half of Hard Dog's cage increased to 1.75x.120 with the door bars. See the pictures (they are also on my website).

EDIT: I consider mine a 6-point roll bar which is different from a 6-point cage. But I agree its not worth arguing over. I don't care either way, below is what I have...haha.

trexbob · 02-20-2008, 09:56 PM

Why the PCM flash, are you changing the heads and cam?

ls1_miata · 02-20-2008, 09:59 PM

Quote:

Originally Posted by trexbob

Why the PCM flash, are you changing the heads and cam?

I've been told it runs a little more timing and gains a little for a stock ls1. It was free. I will probably swap cams out in the future but not any time soon.

JoePZ28 · 02-21-2008, 12:40 AM

Very nice car, hows traction?

ls1_miata · 02-21-2008, 01:04 AM

Quote:

Originally Posted by JoePZ28

Very nice car, hows traction?

EXCELLENT but thats because the car only moves when I push it...haha. Its not running yet. I hope to get the engine fired up for the first time this weekend but thats dependent on me getting it back from the exhaust shop on time which probably isn't going to happen.

Realistically, I am going to have traction issues with anything but drag radials in the first two gears on the street. But its nothing a little feathering can't fix. I could do fender flares and put some big tires on the back but I'm not going to. I've driven a ls1 miata with 205 width bfg drag radials on the street and it hooked up fine, if you didn't drop the clutch you could floor it in first gear.

LS1-450 · 02-21-2008, 06:47 AM

Yah, that's a 6 point alright;......first one I've seen. That's a nice set-up & looks easy to get in & out of.

More about the sub-frame bracing. There is no torque arm. Therefore, the body is the torque arm. Agreed, that the 6 point will help, along w/ the rail supports...etc..

chuntington101 · 02-21-2008, 07:36 AM

looks a great setup!

like the cage to! i have seen it used in mid engined conversions (one for an old mini) and thats what they do! is the chasis much stiff once these mods have been done?? is there anything else you could do (seam weld the shell)??

Chris.

LS1-450 · 02-21-2008, 08:01 AM

Here's what I mean about the C4 brakes. It's all the info. I have. You can see how an after market set-up will be much easier. Either way, it's better to go w/ a GM master brake cylinder as opposed to the stock Miata master, once the fronts are upgraded.

I went to your web page; nice work. Let me know if you need info. for the hydraulic clutch line & master when you get to it. Am not sure if your kit includes the parts needed & the stock GM to throw out bearing fitting can easily be modified & used.

ls1_miata · 02-21-2008, 11:37 AM

LS1-450, thanks for the info. It does appear its easier and maybe even cheaper (if one doesn't have access to machining equipment) to go with an aftermarket set of front brakes.

Quote:

Originally Posted by chuntington101

looks a great setup!

like the cage to! i have seen it used in mid engined conversions (one for an old mini) and thats what they do! is the chasis much stiff once these mods have been done?? is there anything else you could do (seam weld the shell)??

Chris.

Yes, I was able to notice a significant difference in torsional stiffness with the 6-point roll bar vs the old 4-point one I had before. The Miata is known to be a wet noddle so pretty much anything helps. Seam welding, underbody braces, etc. Since I am not racing for money, I'm not going to go through the trouble of seam welding my car. I am seam welding my car club's v8 miata though. But its also gutted and has nothing but the dash skin and a seat. I think the gains from seam welding are small relative to the stiffening methods I already have on my car so that extra bit isn't worth the trouble.

Doc · 02-21-2008, 11:59 AM

Hi. Nice setup. I am the official tuner for RC. Dan and Richard pushed their bone stock LS1 powered Miata to 11.5 @ 120mph last saturday at Gainesville raceway. I can setup the tune in your Miata to run with the big dawgs.

Doc

icantdrift · 02-21-2008, 12:46 PM

cool project, i'd be very interested to see it up close whenever it's done. i've toyed with the idea of building a 2nd LS1 hybrid using a different chassis and having owned a turbo miata naturally that came to mind.

ls1_miata · 02-21-2008, 04:20 PM

Quote:

Originally Posted by icantdrift

cool project, i'd be very interested to see it up close whenever it's done. i've toyed with the idea of building a 2nd LS1 hybrid using a different chassis and having owned a turbo miata naturally that came to mind.

I should be the Annual Georgia Tech Autoshow with the car for sure. Its March 29th at GT in downtown Atlanta. There are always a bunch of sweet cars at it. The public is welcome to view and anyone in the GT community can register their car.

ls1_miata · 02-22-2008, 10:22 PM

Ok, exhaust is done! Buster did a great job and got it done in less than a week. Here are a few pics, more are on my site. Ground clearance is minimal right now but I am going to raise the car back to the stock height to gain an inch or so.

ls1_miata · 02-24-2008, 06:51 PM

Well I was hoping my old Flyin Miata AL race radiator that I had on my car for the turbo setup would work for the ls1 swap. It won't... I haven't uploaded pictures from my camera yet but will later tonight to my site. I knew it was going to be close and that the inlet/outlet location (same as stock miata rad) is not ideal for the ls1 since the ls1 has both on the passenger side of the engine. The radiator will physically fit in the stock location if I cut off one of the lower fan bungs. But even then the radiator has about 1/4 inch clearance so its tight. And of course that requires pusher fans which I want to avoid if possible.

I am either going with a Ron Davis radiator that Racing Concepts has had made for their car or going with a complete custom one from a local fabricator. I am going to check on prices tomorrow and then decide.

ls1_miata · 02-25-2008, 01:24 AM

My old radiator won't work, have to get a new custom double pass one so both inlet and outlet are on the passenger side. I am also going to move it forward so I can put puller fans.

pictures of old radiator not fitting are on my website now.