In reply to frenchyd :
Oh, I understand the advantages of flex fuel, it's just that it isn't vital to getting this setup running. I'll consider it as an addon down the road, especially if the prevalence of E85 spreads (although that doesn't seem to be happening). Or I could go with water/meth injection, which is a simple, proven tech as well
I didn’t read this whole thread again but when I ask “time to move on?”, it is time to move on.
chandler said:I didn’t read this whole thread again but when I ask “time to move on?”, it is time to move on.
Shhhhh........
Can't you see we are enabling here?
chandler said:I didn’t read this whole thread again but when I ask “time to move on?”, it is time to move on.
Somehow we went full circle from making the Miata competitive in STS/STR to getting a C5 Corvette or E36 M3 to building a full force blower motor for the Miata. I don't know. Because GRM.
One thing I have been wondering about is why is "quiet operation" always listed as an advantage of Rotrex blowers? That's a disadvantage. I want people to hear me packing heat.
You can still run a bov. That's something..
Mazda says 0.010"-0.020" of top ring gap, I'm probably going to take it out to 0.025". I'd rather have a slight bit of oil usage and compression leakby then bust the top off the piston.
Yes!! I am running .033 top in a ~3.45" bore in one of my caravans and the blowby isn't even noticeable by my standards.
If you have double the HP of a SM but can barely match their lap times, you aren't stressing the car that much.
That may apply to suspensions but if your engine setup is going to detonate under XYZ conditions when you floor it, it is also going to detonate under the same conditions when Proracer McGoldenshoes floors it. So to the extent that making a boosted motor live depends on understanding how it works and watching it like a hawk, those skills don't necessarily overlap with being able to drive a fast lap. Building a 'driverproof' setup with a bunch of safety features for lean AFR, higher-than-intended boost, excessive coolant or oil temp, boost leaks etc is possible and admirable, but at the end of the day most people don't do them and the driver who catches warning signs and doesn't let his engine fail on track will run more laps than anyone who lets their car break, regardless of how good of a driver they are. So when i hear people talking about 'this much hp before you start having long term durability problems' i interpret that to mean 'you're approaching the point where the engine won't live through a track day where something is not working properly and you don't notice or react appropriately', because there really isn't much metal in a car that fails 'gradually'. Maybe connecting rods if you're running slightly too much rpm. Everything else, whether it's pistons, transmissions, rear ends, axle shafts, etc will pretty much only take damage from brief violent events and then fail completely soon afterwards. They don't gradually take damage or 'wear out' from making 250hp instead of 220hp. So it's not 'my setup only lasted a year at 250hp', it's 'everything was fine at 250hp for one year until a very specific thing happened that i failed to notice or correct in time, and it probably would have lived for years more if i had caught that one thing'. So anyone talking about power levels and 'lifespan' in the same sentence are generally spewing basic misunderstandings of how engines break and can't be taken at face value.
Fr3AkAzOiD said:chandler said:I didn’t read this whole thread again but when I ask “time to move on?”, it is time to move on.
Shhhhh........
Can't you see we are enabling here?
And doing a damn fine job.
Pistons and rings assembled. Those are 0.010" over Mazda Motorsports rings and pistons.
And fired home in the block and torqued. Went with 0.020" top ring gap, 0.022" second ring, after some talking with BP Performance Specialties. Also, check out the meat between the bores. No wonder these can handle 700+hp and 2.5mm overbores with ease.
In reply to NickD :
ooooo Shiny!
Looks good man!
I feel like I missed something - did you get the block machined? Otherwise how can you run .010" oversized pistons? (Do they just fit in the stock bores?)
dculberson said:I feel like I missed something - did you get the block machined? Otherwise how can you run .010" oversized pistons? (Do they just fit in the stock bores?)
I had this block gone through last winter by a machine shop. Grabbed it from a junkyard, numero uno plug was out and that bore was rusty. Machine shop bored it 0.010" over and gave me a set of Mazda Motorsports pistons and rings he had sitting around. I just never got around to assembling it this summer.
Vigo said:One thing I have been wondering about is why is "quiet operation" always listed as an advantage of Rotrex blowers? That's a disadvantage. I want people to hear me packing heat.
You can still run a bov. That's something..
Mazda says 0.010"-0.020" of top ring gap, I'm probably going to take it out to 0.025". I'd rather have a slight bit of oil usage and compression leakby then bust the top off the piston.
Yes!! I am running .033 top in a ~3.45" bore in one of my caravans and the blowby isn't even noticeable by my standards.
If you have double the HP of a SM but can barely match their lap times, you aren't stressing the car that much.
That may apply to suspensions but if your engine setup is going to detonate under XYZ conditions when you floor it, it is also going to detonate under the same conditions when Proracer McGoldenshoes floors it. So to the extent that making a boosted motor live depends on understanding how it works and watching it like a hawk, those skills don't necessarily overlap with being able to drive a fast lap. Building a 'driverproof' setup with a bunch of safety features for lean AFR, higher-than-intended boost, excessive coolant or oil temp, boost leaks etc is possible and admirable, but at the end of the day most people don't do them and the driver who catches warning signs and doesn't let his engine fail on track will run more laps than anyone who lets their car break, regardless of how good of a driver they are. So when i hear people talking about 'this much hp before you start having long term durability problems' i interpret that to mean 'you're approaching the point where the engine won't live through a track day where something is not working properly and you don't notice or react appropriately', because there really isn't much metal in a car that fails 'gradually'. Maybe connecting rods if you're running slightly too much rpm. Everything else, whether it's pistons, transmissions, rear ends, axle shafts, etc will pretty much only take damage from brief violent events and then fail completely soon afterwards. They don't gradually take damage or 'wear out' from making 250hp instead of 220hp. So it's not 'my setup only lasted a year at 250hp', it's 'everything was fine at 250hp for one year until a very specific thing happened that i failed to notice or correct in time, and it probably would have lived for years more if i had caught that one thing'. So anyone talking about power levels and 'lifespan' in the same sentence are generally spewing basic misunderstandings of how engines break and can't be taken at face value.
That's why you cut out my 2nd sentence with an example. Whatever, have a good day.
Sorry, i just didn't see relevance to it. It seemed more like braggadocio than contributing anything to the survival of a boosted motor that is in the works. I feel like if i'm going to help talk someone into doing something i should also help talk someone into making it work out in the end.
Maybe when he is done you can get him to point you by in your 1.6L Miata and then tell him that the only reason his motor is still alive is because he isn't driving it hard enough to keep up with you.
NickD said:dculberson said:I feel like I missed something - did you get the block machined? Otherwise how can you run .010" oversized pistons? (Do they just fit in the stock bores?)
I had this block gone through last winter by a machine shop. Grabbed it from a junkyard, numero uno plug was out and that bore was rusty. Machine shop bored it 0.010" over and gave me a set of Mazda Motorsports pistons and rings he had sitting around. I just never got around to assembling it this summer.
That makes much more sense, thank you!
dculberson said:NickD said:dculberson said:I feel like I missed something - did you get the block machined? Otherwise how can you run .010" oversized pistons? (Do they just fit in the stock bores?)
I had this block gone through last winter by a machine shop. Grabbed it from a junkyard, numero uno plug was out and that bore was rusty. Machine shop bored it 0.010" over and gave me a set of Mazda Motorsports pistons and rings he had sitting around. I just never got around to assembling it this summer.
That makes much more sense, thank you!
Yeah, spring of '16 I pulled this engine out of a car at the junkyard.
The original plan was to overhaul it last winter and run it the '17 season. But a late start an then the machine shop having it for a month pushed it back to installing this year.
This is why it had to be overbored. The engine appeared to have never used/barely used bearings but someone had left the #1 sparkplug out (trying to diagnose a no-start condition perhaps?) and it got filled with water.
Probably too late, but did you look into balancing the rotating assembly? That's a step that's often overlooked but can help oil pump life & other stuff subject to buzziness in these motors.
Dashpot said:Probably too late, but did you look into balancing the rotating assembly? That's a step that's often overlooked but can help oil pump life & other stuff subject to buzziness in these motors.
Yep. For $750, the engine was bored, honed, line-honed, decked, hot-tanked, pistons were installed on rods (pistons, rings and bearings were also included in that $750), crank was polished, head was disassembled and cleaned and rotating assembly was balanced. Yeah, it was a real steal, worth the month wait. The machine work is beautiful.
Unfortunately, I made no progress, because I didn't realize that a new oil pump wouldn't come with the pickup tube gasket or the O-ring and I had to order those, as well as realizing I didn't have the front and rear pan gaskets or a rear main seal. (I could swear I ordered that last one, but I can't find it). So I spent last night chasing those down on the interweb, getting the part numbers from Atkins Rotary and then cross-referencing them into Priority Mazda's site.
NickD said:So I spent last night chasing those down on the interweb, getting the part numbers from Atkins Rotary and then cross-referencing them into Priority Mazda's site.
This sounds complicated. Are you aware of https://store.mazdamotorsports.com ?
RedGT said:NickD said:So I spent last night chasing those down on the interweb, getting the part numbers from Atkins Rotary and then cross-referencing them into Priority Mazda's site.This sounds complicated. Are you aware of https://store.mazdamotorsports.com ?
I honestly forget about that because it's rare that I'm buying stock parts anymore, and the Mazda competition catalog has very little for these cars anymore
NickD said:dculberson said:NickD said:dculberson said:I feel like I missed something - did you get the block machined? Otherwise how can you run .010" oversized pistons? (Do they just fit in the stock bores?)
I had this block gone through last winter by a machine shop. Grabbed it from a junkyard, numero uno plug was out and that bore was rusty. Machine shop bored it 0.010" over and gave me a set of Mazda Motorsports pistons and rings he had sitting around. I just never got around to assembling it this summer.
That makes much more sense, thank you!
Yeah, spring of '16 I pulled this engine out of a car at the junkyard.
The original plan was to overhaul it last winter and run it the '17 season. But a late start an then the machine shop having it for a month pushed it back to installing this year.
This is why it had to be overbored. The engine appeared to have never used/barely used bearings but someone had left the #1 sparkplug out (trying to diagnose a no-start condition perhaps?) and it got filled with water.
I lol'd at the "Pick and Pull Hoist". That looks equal measures sketchy and awesome.
kazoospec said:NickD said:dculberson said:NickD said:dculberson said:I feel like I missed something - did you get the block machined? Otherwise how can you run .010" oversized pistons? (Do they just fit in the stock bores?)
I had this block gone through last winter by a machine shop. Grabbed it from a junkyard, numero uno plug was out and that bore was rusty. Machine shop bored it 0.010" over and gave me a set of Mazda Motorsports pistons and rings he had sitting around. I just never got around to assembling it this summer.
That makes much more sense, thank you!
Yeah, spring of '16 I pulled this engine out of a car at the junkyard.
The original plan was to overhaul it last winter and run it the '17 season. But a late start an then the machine shop having it for a month pushed it back to installing this year.
This is why it had to be overbored. The engine appeared to have never used/barely used bearings but someone had left the #1 sparkplug out (trying to diagnose a no-start condition perhaps?) and it got filled with water.
I lol'd at the "Pick and Pull Hoist". That looks equal measures sketchy and awesome.
Are you referring to the car hiked up on steel wheels so that we could slide the engine and trans out from under the front bumper? Or the two seatbelts tied together? Because the seatbelt trick 100% is proven
In reply to NickD :
I actually missed the seatbelt. I was laughing at hiking up the car on wheels. In my mind, the back end was jacked up, the wheels were slid under as far as they would go and the engine, trans and subframe unbolted. When the last bolt was undone, the car was then tail heavy and catapulted the front end into the air, allowing engine and trans to be slid out. Unbolting was done by your fearless and slightly unbalanced friend (likely named either Bruce or Rusty), who came up with the removal plan while slowly draining a 40oz. If it was anything less epic than that, don't tell me.
In reply to kazoospec :
It was less epic, but still really sketchy. When me, my father, and my friend (Not Bruce, but kinda close at Ben) got there, the car was already pitched up like that, and both subframes and suspension were gone. So the engine and trans were held up in the vehicle by a single wheel wedged standing up under the bellhousing. That was it. An engine and trans just balanced on a steel wheel, and the only thing keeping it from falling over was that the trans case was jammed against the bellhousing. So we laid long prybars over the bay and ran rope over them and around the engine lift plates, heaved the engine up enough to remove the wheel under the trans, set everything on the ground and then had the forklift slide it out from underneath.
Made some progress last weekend after my gaskets showed up.
Oil pan, oil pump and rear main seal adapter RTV'd and torqued.
ARP head studs installed
And cylinder head torqued down. Also started installing the coolant reroute but need thread tape. But there is another big holdup. The new oil pump has an unthreaded hole in it that wasn't present in the factory-installed pump. Do some research and find that all replacement pumps have that hole for the dipstick tube in FWD applications, and that you have to order a $3 blind plug to fill it in. I bought it from a company that caters to Miatas, so why don't they just raise the price the $3 for the plug and automatically include it in the kit, considering probably 99% of the people ordering a pump from them are buying it for an RWD application. So now I'm waiting for a $3 plug + $6 S+H to show up this week. Also had to order a water pump and some coolant seals from Rock Auto, because for some reason I thought that the timing belt kit came with them.
More progress. This is the stupid $3 blind plug that held me up for over a week.
With that done, I could get to wrapping up the coolant reroute and setting up my timing. Let me say that my major bitch with the BP engine family is that the timing procedure sucks. Never should the term "approximate" appear in an engine timing procedure, but this one does.
I got it timed, but it's off a tooth, so I'll have to get an extra set of hands and dig up my FM timing tool. Now the holdup is that I need the timing covers and sensors off the 1.6L currently in the Miata. And I can't put the intake on because A) it'll make it harder to cover the engine with a trashbag and B) I need the bigger fuel injectors from the supercharger kit. So I'm at a standstill for a little bit.
But, my MS PNP showed up today! Bought this before the blower kit, because if things go financially sideways and I can't afford a blower kit, at least I can drop in the beefed 1.8L in naturally-aspirated form.
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