Miata LS3 Build Thread
#21
TECH Enthusiast
Thread Starter
6th gear is .50:1 ... so with 3.73s it's about 2050 rpm at 70 mph in 6th.
3.23 will change that to 1775 rpm.
3.23 will change that to 1775 rpm.
#22
TECH Enthusiast
Thread Starter
I've got the engine out of the car. A Miata doesn't have much room to work around an LS in the engine bay, so H/C/I gets done outside the car. When I put it together I knew this was going to be true, so I've done a lot of work to make the engine as easy as possible to pull. The engine comes out the bottom, with the front subframe attached. I strip the suspension off the subframe first.
Now that the engine's out, I'll be working on splitting it from the trans, and getting it up on the stand. In addition to the Mamo top end, it's also getting an RPS BC2 clutch (with an aluminum flywheel), which I also sourced from Tony. The twin disc Mantic that's in there works great, and will be for sale, but the RPS is lighter, and in a car as light as the Miata, there's no need for any extra weight in the clutch / flywheel. It's easy to get moving.
I built both the wooden gantry crane that lowers the engine out of the car, and this cart that catches it on the floor.
Now that the engine's out, I'll be working on splitting it from the trans, and getting it up on the stand. In addition to the Mamo top end, it's also getting an RPS BC2 clutch (with an aluminum flywheel), which I also sourced from Tony. The twin disc Mantic that's in there works great, and will be for sale, but the RPS is lighter, and in a car as light as the Miata, there's no need for any extra weight in the clutch / flywheel. It's easy to get moving.
I built both the wooden gantry crane that lowers the engine out of the car, and this cart that catches it on the floor.
Last edited by grubinski; 12-29-2019 at 09:16 PM.
The following 2 users liked this post by grubinski:
dreadpirateroberts (01-13-2020), KW Baraka (12-30-2019)
#23
TECH Enthusiast
Thread Starter
Got the first head off ... probably one more day of work until I'm ready to start putting it back together. I was happy to see I have an MLS gasket from the factory, so I probably won't be going through graphite-gasket-removal hell to clean up the mating surfaces.
#24
TECH Enthusiast
Thread Starter
Got a question... The cam will be going in soon (after I remove the old one). After it's in, I'll check timing, PTV, and then measure all 16 valves for correct pushrod length with my short travel lifters.
Do I put assembly lube on the lobes when it goes in, or do I install it dry, take all the measurements, and then yank it to lube before running it?
Picture for status update...
Do I put assembly lube on the lobes when it goes in, or do I install it dry, take all the measurements, and then yank it to lube before running it?
Picture for status update...
#25
ModSquad
iTrader: (6)
You can lube it now and leave it. I’ve never pulled one back out to re-lube. Use a quality oil based lube. Stay away from lithium stuff. LS oil filters are crazy small and the lithium will clog a filter quick.
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grubinski (01-12-2020)
#26
10 Second Club
the ASA fan is kinda **** and even more **** in an ls3. Custom cam all that is required.
#27
TECH Veteran
IF I WAS IN YOURS SHOES
I would have the fast LS3 intake ported and do the radius rod mod.
Send your heads to Frankenstein. His ported LS3 heads are badass. I've seen them outperform other big name aftermarket heads in person. Everyone cant make a LS3 head perform.
Then on the cam... I would cotact a couple people and go with who you feel most comfortable with.
I would have the fast LS3 intake ported and do the radius rod mod.
Send your heads to Frankenstein. His ported LS3 heads are badass. I've seen them outperform other big name aftermarket heads in person. Everyone cant make a LS3 head perform.
Then on the cam... I would cotact a couple people and go with who you feel most comfortable with.
#28
TECH Enthusiast
Thread Starter
LOL. It's a little late to be second guessing what's going into this build. All the parts are here. :-)
I was just asking for a little advice from people who have gone through the pushrod length dance with these lifters.
I was just asking for a little advice from people who have gone through the pushrod length dance with these lifters.
#29
TECH Enthusiast
Thread Starter
Thanks for the reading comprehension, I appreciate it. Lube it is ...
#30
TECH Enthusiast
Thread Starter
The engine is going back together. Heads are on, damper is on. Next step is to measure to get the pushrod lengths. Not sure if the FAST 102 intake will fit under the hood, but we'll see. Worst case, it gets an LS6 manifold, but I may be able to have the stock Miata hood bulge stretched a tad locally if required.
These heads are the MMS220 ... so smaller than a lot of people would put on a 6.2. I did it for street driveability and throttle response. This car is on the street 99% of the time. It weighs 2400#, so it'll be plenty fast with the 220 heads. The 63.5 chambers will yield about 11.8:1 compression with the Cometic .040" gaskets.
These heads are the MMS220 ... so smaller than a lot of people would put on a 6.2. I did it for street driveability and throttle response. This car is on the street 99% of the time. It weighs 2400#, so it'll be plenty fast with the 220 heads. The 63.5 chambers will yield about 11.8:1 compression with the Cometic .040" gaskets.
Last edited by grubinski; 05-07-2020 at 10:18 PM.
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Rich2342 (04-18-2024)
#31
The engine is going back together. Heads are on, damper is on. Next step is to measure to get the pushrod lengths. Not sure if the FAST 102 intake will fit under the hood, but we'll see. Worst case, it gets an LS6 manifold, but I may be able to have the stock Miata hood bulge stretched a tad locally if required.
These heads are the MMS220 ... so smaller than a lot of people would put on a 6.2. I did it for street driveability and throttle response. This car is on the street 99% of the time. It weighs 2400#, so it'll be plenty fast with the 220 heads. The 63.5 chambers will yield about 11.8:1 compression with the Cometic .040" gaskets.
These heads are the MMS220 ... so smaller than a lot of people would put on a 6.2. I did it for street driveability and throttle response. This car is on the street 99% of the time. It weighs 2400#, so it'll be plenty fast with the 220 heads. The 63.5 chambers will yield about 11.8:1 compression with the Cometic .040" gaskets.
You will have insane throttle response and still make good numbers.
im using Mamos 245 afr heads on my 434.
Do your best to fit the fast 102mm intake because the ls6 intake will really hinder your results. You will lose 20-40hp
What cam specs do you have?
#32
TECH Senior Member
That engine is gonna be CRISP! Like Bortous said,.....
I'm curious about the cam as well. Unless it's classified, and I don't wanna die...lol
I'm curious about the cam as well. Unless it's classified, and I don't wanna die...lol
#33
TECH Enthusiast
Thread Starter
Cam is 227/232 114+1 .613/.610... mild on purpose. 1.8 rockers are going to give .649/.646 lift. I think Tony uses this cam a lot on his builds.
#34
TECH Enthusiast
Thread Starter
I have some tricks up my sleeve. I think the point of minimum clearance is going to be right under a reinforcement brace on the bottom of the hood. I can cut that out.
#35
Good lift to go with it too.
It will drive great.
I think he did mention something about using a 227 cam in some of his older builds.
Even with my camshaft its close in spec to a 454 he did with the 245cc head.
#36
TECH Enthusiast
Thread Starter
Did some test fitting of various parts today, Rockers and intake manifold. I'm going to have to touch the valve cover rails a bit with a grinder to make room for the rockers. I **hope** the intake manifold clears my hood ... it sticks up a bit more than the stock LS3 manifold.
The intake manifold is a bit taller than the stock LS3 ... I'm hoping it clears the hood. I have a few tricks up my sleeve if it doesn't, but I may have to go to an LS6 intake as a last resort.
A bit too close ... will grind by the blue dot just a touch for clearance.
Setting up to measure for pushrod lengths.
The intake manifold is a bit taller than the stock LS3 ... I'm hoping it clears the hood. I have a few tricks up my sleeve if it doesn't, but I may have to go to an LS6 intake as a last resort.
A bit too close ... will grind by the blue dot just a touch for clearance.
Setting up to measure for pushrod lengths.
#37
That intake looks nice.
I have the same one but with the Fast fuel rails to go with it.
It does bulge a bit compared to the stock intake though.
I compared it to my old Fast 102mm LS3 intake and this cathedral one seems a bit bulkier.
Can you also take a nice clear pic of one of the intake runners?
I like checking out the work that has been done.
It looks like jewellery.
I have the same one but with the Fast fuel rails to go with it.
It does bulge a bit compared to the stock intake though.
I compared it to my old Fast 102mm LS3 intake and this cathedral one seems a bit bulkier.
Can you also take a nice clear pic of one of the intake runners?
I like checking out the work that has been done.
It looks like jewellery.
#39
ModSquad
iTrader: (6)
Slam the hood a few times...it will fit. 😂😂
#40
ModSquad
iTrader: (6)