i may have to back-pedal. if you have that much power you don't need to remove windows and wipers and all the rest. has anybody documented how much a ls swap weighs when car is stripped? (maybe orion or zx?)

No, I just want to see what peoples thoughts on the subject. I don't care if its negative as long as it it is helpful.

I think of the Forums as a car meet at any parking lot and your just asking people stuff and with my question is just with in some parameters.

SR20 FTW im in the process of landing one! Will post pics when i do!

I have a sr sitting in my back shed doing nothing and I still dont think its worth it.

Custom mounts, tail shaft, wiring, a dry sump (are you made of money?), actually buying all the parts for the sr (cams, rocker arm stoppers, cam gears, if you want 400hp you will have to build it) at 400 you will pop a gearbox pretty fast so you may as well put a vg box conversion before you get a custom tail shaft.

If you're serious about a vl conversion you will need custom intake manifold, all the install...

Its a lot of money for the sake of being different... If you did 13b conversion at least you might be able to drop some weight.

Vilko you have a point in spite of your ridiculous straw man. Yes, mounts tranny adapter oil pan are all significant items, no doubt. The sr is a factory turbo motor and would work great a miata in basically stock form up to around 350hp (with an injector+turbo upgrade). This means you could blow up your ---- and buy another det motor and swap it in.

For 400whp you're right, you will need cams and a head gasket. I think with a 3071ish sized turbo, 400 is pretty doable. There are a lot of people running in this power area with stock gearboxes. as power goes up from here, longevity goes down.

That said, the mt.n community is not particularly sympathetic to motor swaps such as the sr. Recent history shows people show up with grand ideas, talk big, and then disappear. To-date nobody has demonstrated any kind of return on investment for the swap. So the community is skeptical.

This is as it should be.

speaking personally, i'm part of the problem. this summer i'll have been sitting on my sr swapped miata for 5 years without demonstrating either power or reliability. I hope to fix that soon, but who knows.

IMO the SR20 doesn't offer enough benefit to offset the cost and pain in the ass installation, etc. If you are going to do it go with an F20C...

A built BP can run over 400 with the correct tune, supporting mods, etc. It may be easier with an SR20 if you have a lot more time and money.

The B6 can also make those numbers, but it is easier with the extra displacement the BP offers. I picked up a BP from the junkyard with 36,000 miles for $200. It was from a 1993 Ford Escort GT. There are several other cars running the BP as well so they are dirt cheap.

Between me and my brother we own about 4 sr20s, and have owned a few more. And a lot of my friends are heavily involved in the drift scene. I'm not claiming to be an expert, but I know a bit about these motors.

Im not too familiar with hp, and if OP was referring to atw or at the fly. Im going to assume atw.

In my brothers car he has about 210-220rwkw, his 5 speed is giving up. 350hp and I think you will start having troubles after the first few spirited outings. Obviously SR 6 speeds are a joke, so you are going to want an RB25 or VG30 box for reliable power. Sure gear boxes are pretty cheap to replace, but if you are going to all the trouble of a conversion you would be aiming for reliable power, no?

I don't know what SR putting out 350hp atw on stock cams. There are drag motors with stock bottom ends that push that power, but they have the cams, etc done. And they don't usually last long.
The 220kw in my brothers car is on a responsive hks turbo, cams, tune and all the usual intake/exhaust/front mount, stock bottom end, 98octane (Australian rating system). Ethanol will help, but not to the power levels the OP was talking about.

Head gasket? Ive never heard of anyone with a sr upgrading just the head gasket unless its to decomp a non-turbo sr or its a fully build motor.

You make a good point with the ability to blow up an engine/gear box and replacing it for cheap. Im living in Australia so that is especially true.

IMO if you want that power from a SR, you are going to have to build it. This forum has led me to believe that for a lot cheaper you could build a 1.8 and put out the same power.

If you are going for 350whp, it would be pointless to do the SR20 swap. You can get that for sure on the BP and it won't take tons of work.

Or you could swap a v8.

Vilko, for sure at 350whp, the BP is the better choice with time and money as consideration.

thats interesting, i get 300whp ~= 220kw. how many 5 speeds has he broken? most of my datapoints are folks running rwd tranny at around 350whp (2871 @ 15psi) and they hold up ok on road course usage. folks doing autox with ka+t (400whp) and sticky tires go through them though.

anyway, sorry to jump on you. my personal opinion is that it is remarkably hard to make a turbo motor reliably produce power levels above 350whp using gas we can afford (91 octane in cali). i think any demonstrations of doing so should be considered an interesting datapoint.

admittedly its the upper end of stock cams but you can with a non-restrictive turbine (ie: not a t28).

u mean BUILD it? props to u aussies :bowrofl:

At 220kw you wont need to replace them too often, this one has stood up for years. But for the sake of reliability at 350-400hp you may as well do the swap before you get a tailshaft made up IMO. Do it once, do it right.

Yeah, T28 wouldnt even get close lol. Im suprised you can get out 300hp from stock cams, news to me!

Mmmm... VE... Thats a different story! ---- the budget, just drop in a Mazworx SR24VE!

I know a guy who weighed the major components. He said the LS motor was lighter, but the tranny and rear end where heavier, everything included it added up to about a 100lb gain... at least the weight is in the middle/rear and not the front of the car.

But for comparison sake, the same LS1 in a Fbody weighs in at about 3600#. Power to weight ration the LS1 Miata is much better.

Ya 13b is not light
http://forum.miata.net/vb/showthread.php?t=338950

With all the conversation about having to build a SR and if it would hold up to that 350-400hp range. The LS1 would be easier, but if done it would be the typical American thing "Just put a V8 in it". I don't like to do that. With only a 100 lb gain that would be easy to adjust the weight for that CF Doors -60 lbs, seats -20 lbs. There are a lot of conversion kits out there and a lot of people that already done them that could help.

jasonb--- The aussies are lucky because they get the Euro, Japanese and most of the American cars.

get two hyabusa motors and connect the crankshafts.

Thats about as unamerican v8 as you can get?

Are you talking about this little baby lol, its only a twin turbo 1000 hp 2.8 liter


https://www.miataturbo.net/attachmen...ine=1333648323

https://www.miataturbo.net/attachmen...ine=1333648323

:drool:

Coming from a bike background, if that is an bike inline 4 converted to v8, I LOVE it!!

Revs, glorious sound, torque, top end power.....crazy !!!

Although I would be just as happy without the turbo's....

But I wouldn't say no....either way.

Where you getting these?

They will build you anything you want, if you want a dash made they will do it. It is the same place that Sport Compact Car lost 154 lbs in exterior body parts.

http://www.modified.com/projectcars/...k/viewall.html

http://www.axispowerracing.com/miata.html