Building a 20B - Opinions on this build..
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Thread Starter
Junior Member
Joined: Oct 2008
Posts: 5
Likes: 0
From: Queensland
Building a 20B - Opinions on this build..
Hey,
Been doing a little bit of reading and want to build up a 20B turbo for a Series 8 RX7. Here are some of the parts that I have came up with so far...
New Kiwi-Re E-shaft or MPS e-shaft
Turbonetics billet centre plate
New front end plate, intermediate plate and rear plate
New Rotor housing
Hogans Racing manifold
3 stage peterson dry sump pump
ect ect...
Haven't read too much about seals for the moment.
Looking at running either a HKS T51R SPL or Garret GT45 series turbo with a Tial stainless steel exhaust housing. Hope to run it through a Tremec TKO600 box with motoc M800 running the show...
Probably a bit of an overkill but I would rather do it right the first time...
On the right track? As you can see, money doesn't really matter too much...
Been doing a little bit of reading and want to build up a 20B turbo for a Series 8 RX7. Here are some of the parts that I have came up with so far...
New Kiwi-Re E-shaft or MPS e-shaft
Turbonetics billet centre plate
New front end plate, intermediate plate and rear plate
New Rotor housing
Hogans Racing manifold
3 stage peterson dry sump pump
ect ect...
Haven't read too much about seals for the moment.
Looking at running either a HKS T51R SPL or Garret GT45 series turbo with a Tial stainless steel exhaust housing. Hope to run it through a Tremec TKO600 box with motoc M800 running the show...
Probably a bit of an overkill but I would rather do it right the first time...
On the right track? As you can see, money doesn't really matter too much...
Rotary Enthusiast
Joined: Dec 2004
Posts: 991
Likes: 1
From: Los Angeles
How much power are you planning for?and what its the use for?
You have a list that is very expensive.
If you have the right funding,then those are the best parts money can buy.
If you want something to be realiable, a stock late model 20B will do the job
and save you lots of money to buy extra engines and other things depending on what type of racing you want to do.Ive have had plenty of 20B powered cars and believe me,ive blown some here and there and you don't wanna blow an engine with the best parts like your list.Your list is easly 20-30k in parts and thats not the hole setup.You can do the same with the stock block for that price and have the same amount of reliablilty and power with the proper tune and Apex seals.I know money does not matter to you but from past experience,the best parts can also break too,its all in the tune and combination of fuel and ignition.
You have a list that is very expensive.
If you have the right funding,then those are the best parts money can buy.
If you want something to be realiable, a stock late model 20B will do the job
and save you lots of money to buy extra engines and other things depending on what type of racing you want to do.Ive have had plenty of 20B powered cars and believe me,ive blown some here and there and you don't wanna blow an engine with the best parts like your list.Your list is easly 20-30k in parts and thats not the hole setup.You can do the same with the stock block for that price and have the same amount of reliablilty and power with the proper tune and Apex seals.I know money does not matter to you but from past experience,the best parts can also break too,its all in the tune and combination of fuel and ignition.
Last edited by 61620B; Dec 31, 2008 at 12:05 AM.
Joined: May 2001
Posts: 2,390
Likes: 2
From: San Francisco, CA
Use the Mazdaspeed dry-sump front cover.
Try out the new billet aluminum rotors in your engine, they're only $2k each or at least lightened rotors like what Racing Beat offers.
Try out the new billet aluminum rotors in your engine, they're only $2k each or at least lightened rotors like what Racing Beat offers.
Thread Starter
Junior Member
Joined: Oct 2008
Posts: 5
Likes: 0
From: Queensland
How much power are you planning for?and what its the use for?
You have a list that is very expensive.
If you have the right funding,then those are the best parts money can buy.
If you want something to be realiable, a stock late model 20B will do the job
and save you lots of money to buy extra engines and other things depending on what type of racing you want to do.Ive have had plenty of 20B powered cars and believe me,ive blown some here and there and you don't wanna blow an engine with the best parts like your list.Your list is easly 20-30k in parts and thats not the hole setup.You can do the same with the stock block for that price and have the same amount of reliablilty and power with the proper tune and Apex seals.I know money does not matter to you but from past experience,the best parts can also break too,its all in the tune and combination of fuel and ignition.
You have a list that is very expensive.
If you have the right funding,then those are the best parts money can buy.
If you want something to be realiable, a stock late model 20B will do the job
and save you lots of money to buy extra engines and other things depending on what type of racing you want to do.Ive have had plenty of 20B powered cars and believe me,ive blown some here and there and you don't wanna blow an engine with the best parts like your list.Your list is easly 20-30k in parts and thats not the hole setup.You can do the same with the stock block for that price and have the same amount of reliablilty and power with the proper tune and Apex seals.I know money does not matter to you but from past experience,the best parts can also break too,its all in the tune and combination of fuel and ignition.
thanks for that input too, gives some food for thought, as you said its all basically in the tune.
Does anyone know if anyone else will be developing billet centre plates? i really really hate turbosmart...
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Thread Starter
Junior Member
Joined: Oct 2008
Posts: 5
Likes: 0
From: Queensland
I am looking at using Series 6 rotor housings and seen that the front and rear rotor housing have different part numbers. Would this mean that I buy1 x front and 2 x rear?
Need to do a bit more research to make sure they would suit the billet centre plate and dry sump front cover
Need to do a bit more research to make sure they would suit the billet centre plate and dry sump front cover
Full Member
Joined: Oct 2004
Posts: 87
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From: sydney
info on eshafts for a 20b
https://www.rx7club.com/showthread.p...hlight=mps+20b
someone correct me if i am wrong but if your mounting the 20b in a rx7 you will need to use the rx7 rear endplate for the standard engine mount position in the rx7.
The standard 20b intake and midplate will be more than enough for your street rx7 at 800hp, to give you an example - i've seen and know the owner of a 20b down here that runs a standard midplate, standard intake(extrude honed), GT47 turbo, runs on methanol and is wet sumped that runs 7.5secs. The motor hasn't been opened for over 1 year and races at nearly every meeting he can.
https://www.rx7club.com/showthread.p...hlight=mps+20b
someone correct me if i am wrong but if your mounting the 20b in a rx7 you will need to use the rx7 rear endplate for the standard engine mount position in the rx7.
The standard 20b intake and midplate will be more than enough for your street rx7 at 800hp, to give you an example - i've seen and know the owner of a 20b down here that runs a standard midplate, standard intake(extrude honed), GT47 turbo, runs on methanol and is wet sumped that runs 7.5secs. The motor hasn't been opened for over 1 year and races at nearly every meeting he can.
Banned. I got OWNED!!!
Joined: Apr 2004
Posts: 478
Likes: 1
From: Menasha, WI
I think there seem to be a couple of different groups of 20b "build-types". As has been pointed out, you can build a reliable high hp motor without using the exotic parts and I don't really think personally that they add much if anything ultimately to the quality of the motor. However, it is a "quest" of sorts to some people to spend a lot of time finding what are deemed to be the "best" and most expensive of each part and then take eons to build the motor. I have yet to see anybody build an 800 hp 20b, however. Maybe there are a few drag motors out there I am forgetting, but the bulk of these make 550-650 hp. Given the torque and how difficult it is to control the cars with even that much hp, I have no idea why anyone would want one.
Others build a very straightforward motor based around a fairly "stock-ish" setup and have a very workable 350-450 hp motor in no time and for little cost. These days a good build that follows a known path seems to get 550-600 fairly readily.
However, since you seem to b e going for the all-out quest thing, you should probably use a Pectel ecu instead of the Motec. It's a far better box and costs a lot more. That's what Chris Carlisi has on his motor and its a real piece of work.
Gordon
Others build a very straightforward motor based around a fairly "stock-ish" setup and have a very workable 350-450 hp motor in no time and for little cost. These days a good build that follows a known path seems to get 550-600 fairly readily.
However, since you seem to b e going for the all-out quest thing, you should probably use a Pectel ecu instead of the Motec. It's a far better box and costs a lot more. That's what Chris Carlisi has on his motor and its a real piece of work.
Gordon
550-600, although I wouldn't yet say its "common" is in my opinion quite easily done with a 13B. With the addition of AI, this can also be done reliably, which is key. Did I mention on pump gas?
The power curve, and low boost needed for the 20B is compelling, and that I can't take away, but if simply making a reliable 550-600 is your goal, It can be done with the 13B.
A "Quest" build on a 20B? I would think 1200-1500 rwhp. Otherwise, Gordon and Series3 you're correct, using all the expensive parts are basically not needed. Not to stir anything up at all, so don't take it that way... I just don't see the need to go to a 20B and all the related costs just to make 500-600 rwhp.
Everything else aside, whichever route you go, you will want to run some sort of AI, whether it be water or meth injection. Either will reduce your intake air temps like nothing else can, race gas aside.... Take the heat out of the rotary, enjoy long reliable motor life.
Banned. I got OWNED!!!
Joined: Apr 2004
Posts: 478
Likes: 1
From: Menasha, WI
JDMFantasy... I have very seldom seen a 20b making more than 600 whp. There are a few I know, but most of them are making 500-600 whp. And, yes, you can make that much readily enough with a 13b, but there would be a huge difference in torque. The similar hp'd 20b would absolutely eat the 13b alive in any instance you could think imagine. And, aside from the numbers or what wins what, there's just that huge difference in power delivery, and for those who care, the sound of a truly exotic motor (versus the buzzing of a 2 rotor).
Gordon
Gordon
Your statement about a similar powered 20B eating a 13B alive in any instance, and go on to say numbers aside there's the huge difference in power delievery... well, a similarly powered 20B would come out on top due to that power delivery... otherwise a X amount of horsepower is X amount of horsepower, doesn't matter what the motor is.
And a GT47 is plenty turbo...
^ and a 13B will never SOUND like a 20B. You don't even need to drive the 20B to enjoy it. Just start it and let it idle in the garage. Pull up a seat, grab a beer and let your ears orgasm.
Banned. I got OWNED!!!
Joined: Apr 2004
Posts: 478
Likes: 1
From: Menasha, WI
JDMFantasy... I understand that you don't see the need for a 20b -- for the $ it would cost -- for the same 500 hp as a 13b. It costs a lot of money. I gather you would only spend this type of money for an 800 hp motor, or so. However, I've seen quite a few people spend $50-75,000 and end up with 550-600 hp 20b motors. Not intending to say you cannot build an 800 hp 20b, because I think there are a few of them around. Just not many 700+ motors out there and, if there were, its my opinion they would be totally useless on the street.
However, to be clear, the 20b will make, say, double the torque at 2000 rpm or so that a 13b will -- assuming a 500 hp 20b and a 500 hp 13b -- and that's why the 20b will eat the 13b of same hp. So, I'm not sure I understand your point about 500 hp is 500 hp. The "power" -- the torque -- of the two motors -- having the same maximum hp -- is entirely different. Put another way, a 500 hp 20b is comparable to an ~650 hp 13b.
Gordon
However, to be clear, the 20b will make, say, double the torque at 2000 rpm or so that a 13b will -- assuming a 500 hp 20b and a 500 hp 13b -- and that's why the 20b will eat the 13b of same hp. So, I'm not sure I understand your point about 500 hp is 500 hp. The "power" -- the torque -- of the two motors -- having the same maximum hp -- is entirely different. Put another way, a 500 hp 20b is comparable to an ~650 hp 13b.
Gordon
Given the choice I'd go 20B too I'd say, but $50-75K for a 500hp? Why?
You know it aggravates me when people always put a cost per hp on projects like this. I see this all the time when people try to understand why we do 20b projects in the 1st place. For a majority of us it's not about that. It's about having something more exotic than the next person and a chance for more reliability because of the 20b's displacement advantage. You do realize that there are only about 4,500 examples of these engines in existence?
ABIEX is one user who is supporting over 1300hp on his 20B (E85).
The last I spoke with Carlos Lopez, Gabi (ABIEX) was climbing even higher.
I've got details on his build and they're nothing like what the OP is taking about.
I really agree with Gordon on the ECU point. They're very complex ECU's with tons of options to configure. I've got mine configured really sick, real sick.. stuff the M800 can't do (yet).
but what makes Pi/Pectel even better is they didn't support rotary or the OMP but thanks to Chris and Neel @ Apexspeed - now they do... try that with a MoTec :-)
The last I spoke with Carlos Lopez, Gabi (ABIEX) was climbing even higher.
I've got details on his build and they're nothing like what the OP is taking about.
I really agree with Gordon on the ECU point. They're very complex ECU's with tons of options to configure. I've got mine configured really sick, real sick.. stuff the M800 can't do (yet).
but what makes Pi/Pectel even better is they didn't support rotary or the OMP but thanks to Chris and Neel @ Apexspeed - now they do... try that with a MoTec :-)
Junior Member
Joined: Feb 2009
Posts: 15
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From: california
honestly, no matter what car you drive "cost per hp" is never a great way to document your success. If you wanted bang for buck, you obviously started with the wrong car. Rotaries arent meant to be dyno queens.
many people go with a 20b because a N/A 20b can make as much as most 13b Turbo's can make. 20bs sound better, spool their turbos up faster, and are more reliable due to having more displacement so it takes less strain on the engine to produce that certain number.
many people go with a 20b because a N/A 20b can make as much as most 13b Turbo's can make. 20bs sound better, spool their turbos up faster, and are more reliable due to having more displacement so it takes less strain on the engine to produce that certain number.
I'm only saying that if our r&d was as great/demanding as the other engine.. we'd also have stupid high hp cars,etc.. then again - thats not a world i want to be apart of. at least with my 3r swap, its in a class of its own. we can pull into a parkinglot with tons of domestic muscle and actually be unique (and manage to keep up or even win!).
