So this is my intro thread, my name is Todd and I was sent here from MiataTurbo.net. I currently have a 1999 Emerald Green that I bought in early 2007. It was bone stock except for the 16" Motegi wheels that were on it, and it had 103,000 miles. I turbo'd it and played around with many different megasquirt setups, and last week I went in a different direction, V8. Yesterday I picked up a 5.3 out of an 01 Silverado complete minus coils, for $200. So I have many questions related to a V8 swap, and I'll ask them now to get it over with.
1) If I swap my iron block 5.3 in there with a T-56, what would the average final weight be? My car weighs about 2350 now by itself. My goal with the turbo setup was 235 HP so the car by itself would have 1 hp per 10lbs, but I have no idea what HP goals I'd want with the V8. I know I want the car to run 11.90's in the 1/4 mile and get at least 25mpg as a daily driver.
2) Would a Walbro 255 fuel pump ('99 replacement) be ok to use for the V8?
3) What are my options to use for the differential? I mean what gearing / is this something I can get from a salvage yard? I heard something like running an 8.8 from a T-bird Turbo coupe?
4) What wheels can I use? I mean, can I use the ones that are on my car now? I was thinking about getting black 6UL's (15") instead of keeping my 16 inch motegi's, but what tire size is commonly used for a V8 swap?

That should do it for now. Feel free to bust my ***** about my inability to "use the search feature".

 

Read on M.net's engine conversions forum. A TON of us are in the middle of building them, and a few guys have some great pictures of the progress. I will be updating my build thread as soon as UPS gets my camera on my door step.

Add 80 pounds to the build compared to the aluminum block. I'm following Lee down this path a bit with "who cares so much about weight". As a DD, it must have heat, AC, and power steering. I added insulation/sound deadener to help more with creature comforts.

255= what everyone is running

Rear end options- 8.8 ford, 7.5 ford, 8 inch TII rear, 8 inch 929 rear.

If I were to do it again, I'd run the 7.5 ford in a heartbeat with Martins hangers and the new axles posted on M.net. Install a 3.55 gear and a Detroit true trac.

Wheels- run what ya brung, but hope you have enough. I have a stack of 6UL's waiting here for TireRack to get RS3's in stock again

 

So aside from the engine, ecu, and trans, how much money will I have involved just to get this running and driving?

 

If you have to ask, you really don't want to get into it.....

 

Exhaust- 2000
intake setup-200
cooling-700 (radiator, LS2 waterpump, surge tank)
Fuel system-between 150 and 550+ (I have 500+ into my basic fuel system counting injectors)
rear end- they are now getting them in around 1200 once said and done
driveshaft- 200 once you add the extra stuff needed
Kit- 1800
Master cylinder kit-200
Oil pan- 650
Relocation kit+ cooler-100 or so

I'd keep rattling things off, but it is late and my fingers are done haha

If your going to do it, close your eyes and come on in. If you think you can live without it- run away..... fast. I personally could not live another day with the turbo4 sitting in front of me.

 

I'm doin it, there's no more if's in my mind. I'm goin to start collecting parts and let time takes it's toll. What does your ls1 car weight by itself (no driver)? I just want to know in lbs how much mine will weigh, then I can figure out my hp to weight ratio so I know what needs to be done to the engine.

 

Not mine, but should be close for you if you had an aluminum block-
http://www.pbase.com/beagleracing/image/114977713

Sell the iron block setup on ls1tech and search for an L33

 

I wanted to use this motor cause I just picked it up on Friday for $200 complete minus coils. What frame kit are you using? I looked at the boss frog, but I like the support that flyin miata has. What would you recommend?

 

I went straight to V8Roadster, which is who supplies FM.

 

Which LS motor are you using? I'm running some 225/50R16 T1R's and they hook up pretty good with the 480 HP LS3 GM crate motor that we are using. We have a 3.42 rear end and last week on a short trip, got just over 27 mpg! We used the V8R kit mostly because we wanted to try to retain as much of the great Miata handling as we could and felt that the V8R kit was the best one out there to do that, in as much as it retains the most rearward motor mounting position available. Not to mention that the overall quality that V8R is turning out, is very good. I have almost $30k in the conversion using new "everything" and for the handling/performance/reliability of the end product, I consider it to be a bargan! Have fun and enjoy your build! 1st time you get to run it thru the gears, whatever you have spent on it, will be many times worth it! Wiz.

 

His engine will make around 260-275rwhp