Turbo setup for rally cross/autocross
01-14-2013, 02:59 PM
#41
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OK, got it, Ill do the rods !
Pistons worth it too ??
Had some questions about the Manifold - saw somebody recommend cast - for fast spool is short and unequal length a better trade off than long and equal length ? What are some good mani's to look for ? I have no Power steering or AC to worry about.
Thanks !
Pistons worth it too ??
Had some questions about the Manifold - saw somebody recommend cast - for fast spool is short and unequal length a better trade off than long and equal length ? What are some good mani's to look for ? I have no Power steering or AC to worry about.
Thanks !
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01-14-2013, 05:02 PM
#42
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The tradeoff between a cast and tubular manifold at those power levels and that turbo size would be minimal. You wouldn't notice a difference.
I recommend cast with inconel studs just for pure durability.
I recommend cast with inconel studs just for pure durability.
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01-14-2013, 05:19 PM
#43
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Cast with inconel studs is ideal for durability. That kit I keep referring in the classifieds is such a well-built piece though that I really think you'd have just as good of luck with that, and it's cheaper than a new cast manifold. In terms of performance, Dillon is right -- you're gonna hit your goals either way, likely won't make a huge difference.
Now buy something.
Now buy something.
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01-14-2013, 05:55 PM
#44
Considering you're necessity to build an engine and your power goals and the fact that it well be hard to meet that at your budget period. Why not consider a 1.8 custom made form Rebello racing in Antioch Ca. They can get 190 hp to the wheels with it naturally aspirated. Super reliability lots of bottom end. They use a long rod redesign(honda con rods) with custom pistons and it revs to 8k at $4700.
They have been making some of the absolute finest most reliable high hp engines for SCCA racing sense 1984. There number is (925) 754-4871
They have been making some of the absolute finest most reliable high hp engines for SCCA racing sense 1984. There number is (925) 754-4871
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01-14-2013, 06:16 PM
#45
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Considering you're necessity to build an engine and your power goals and the fact that it well be hard to meet that at your budget period. Why not consider a 1.8 custom made form Rebello racing in Antioch Ca. They can get 190 hp to the wheels with it naturally aspirated. Super reliability lots of bottom end. They use a long rod redesign(honda con rods) with custom pistons and it revs to 8k at $4700.
They have been making some of the absolute finest most reliable high hp engines for SCCA racing sense 1984. There number is (925) 754-4871
They have been making some of the absolute finest most reliable high hp engines for SCCA racing sense 1984. There number is (925) 754-4871
Back to the original poster, you really don't need to do anything to the stock engine for 200whp. I just thought you were doing it already because of one of your previous posts. I would choose the Boundary oil pump over the rods if it were me. The rods take a beating from too much engine torque or overrevving the engine from a missed shift. The oil pump gears fail from prolonged higher than stock rpms (racing) or when there is too much engine torque. Since you will not be able to make too much engine torque with a 2554 size turbo, I wouldn't worry about that so much.
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01-14-2013, 07:26 PM
#46
How long do you drive in a avg. rally cross? Just wondering because if you do indeed have fab skills or know people with them you can make some pretty decent manifolds for not much money and they should be reliable. I've never had an issue with mine (though I haven't autocrossed it or anything ever). I do beat on it and daily it with no issues. Also in its first iteration (log with essentially a gt2554) it was ridiculously responsive. Oh yeah that was with the stock exhaust too, made for good time toying with unsuspecting cars.
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01-14-2013, 08:49 PM
#50
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How long do you drive in a avg. rally cross? Just wondering because if you do indeed have fab skills or know people with them you can make some pretty decent manifolds for not much money and they should be reliable. I've never had an issue with mine (though I haven't autocrossed it or anything ever). I do beat on it and daily it with no issues. Also in its first iteration (log with essentially a gt2554) it was ridiculously responsive. Oh yeah that was with the stock exhaust too, made for good time toying with unsuspecting cars.
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01-15-2013, 01:06 AM
#51
If your budget is that modest I would suggest a used manifold, inconel hardware, and an ebay journal bearing turbo of the equivalent size to the 2554. You could pick up the ebay turbo brand new for $200-250. Or you could take your chances with a used gt25 (same size, different name for it) from a Nissan SR20($50-125 depending on quality) and/or rebuild one. Rebuild kits are $40-50 on ebay.
Rebuilding the engine will cost you a minimum of $1800 with forged rods, pistons, Boundary Engineering oil pump, gaskets and machining. A MegaSquirt will set you back $400-800 depending on what and where you get it once you add an IAT and such. Wideband O2 will be $150ish. You will need injectors and they aren't free, either. It adds up quick.
Rebuilding the engine will cost you a minimum of $1800 with forged rods, pistons, Boundary Engineering oil pump, gaskets and machining. A MegaSquirt will set you back $400-800 depending on what and where you get it once you add an IAT and such. Wideband O2 will be $150ish. You will need injectors and they aren't free, either. It adds up quick.
Here is the original thread:
RB20DET T3 Turbo - Miata Turbo Forum - The Miataturbo of miata turbo sites
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01-15-2013, 11:29 AM
#52
Why do you need more power for rally-x? I did my first one this weekend in the wrx and I had WAY TOO MUCH power. Road dyno makes it out to something like ~320ftlbs/240hp, yes I make ALL THE TORQUE, because 2.5L with td04. And thats a heavy AWD car, I basically couldn't use more than ~1/2 throttle without just spinning up the red line. If anything for a miata, I would just copy the 949 rental engine build, since your main forms of racing involve having near zero grip or doing exactly the speed limit of the road for 12 hours.
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01-15-2013, 12:40 PM
#53
Why do you need more power for rally-x? I did my first one this weekend in the wrx and I had WAY TOO MUCH power. Road dyno makes it out to something like ~320ftlbs/240hp, yes I make ALL THE TORQUE, because 2.5L with td04. And thats a heavy AWD car, I basically couldn't use more than ~1/2 throttle without just spinning up the red line. If anything for a miata, I would just copy the 949 rental engine build, since your main forms of racing involve having near zero grip or doing exactly the speed limit of the road for 12 hours.
Turbo - not so much.
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01-15-2013, 01:57 PM
#54
The difference between 200whp and 250whp for a rallyx Miata IMO isn't worth it.
I'd say instead of building a motor, you should get a rock solid turbo setup and spend the extra work bracing it and preparing it to take big bumps and vibrations. Aim for like 200whp and use a stock motor, if it blows just replace it with another $500 motor. The last thing you want is your manifold cracking off or the turbo coming loose or piping coming loose.
I'd say instead of building a motor, you should get a rock solid turbo setup and spend the extra work bracing it and preparing it to take big bumps and vibrations. Aim for like 200whp and use a stock motor, if it blows just replace it with another $500 motor. The last thing you want is your manifold cracking off or the turbo coming loose or piping coming loose.
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01-15-2013, 02:01 PM
#55
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The difference between 200whp and 250whp for a rallyx Miata IMO isn't worth it.
I'd say instead of building a motor, you should get a rock solid turbo setup and spend the extra work bracing it and preparing it to take big bumps and vibrations. Aim for like 200whp and use a stock motor, if it blows just replace it with another $500 motor. The last thing you want is your manifold cracking off or the turbo coming loose or piping coming loose.
I'd say instead of building a motor, you should get a rock solid turbo setup and spend the extra work bracing it and preparing it to take big bumps and vibrations. Aim for like 200whp and use a stock motor, if it blows just replace it with another $500 motor. The last thing you want is your manifold cracking off or the turbo coming loose or piping coming loose.
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01-15-2013, 07:23 PM
#59
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There are quite a few in Michigan. But it think that's due to the amount of subarus in this state, everyone and their cousin has a subaru around here.
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01-15-2013, 07:49 PM
#60
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Yeah, looks like things are pretty sparse in my part of CA. Cal Club (CSCCR) looks like they run pretty frequently, zilch in San Francisco (SFR). Of course, most of the calendar is still broken on the SFR site, so god only knows. NorPacDiv shows ONE event in CA... from 2010 
This looks like a "what to do with your winter beater during the summer" racing series. I guess that explains why its not so popular out here on the left coast, other than the mossbacked cascadians.
Anyway, carry on. Don't let me derail things.
This looks like a "what to do with your winter beater during the summer" racing series. I guess that explains why its not so popular out here on the left coast, other than the mossbacked cascadians.
Anyway, carry on. Don't let me derail things.
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