Need help/lessons/advice for picking out a turbo
12-03-2010, 09:41 PM
#1
U-Stink-But-I-♥-U
Thread Starter
iTrader: (1)
Join Date: Mar 2005
Location: 12 o'clock on the Beltway.
Posts: 2,004
Likes: 0
Received 1 Like
on
1 Post
Need help/lessons/advice for picking out a turbo
I have a motor built to handle a good deal of abuse (build by KDR/Speed1) but no snail to match it. I have decided to bite the bullet and have a custom manifold/dp and other related piping done by someone that knows what they are doing; however, I havent settled on a turbo to build around.
I am looking for a list of possible, off the shelf turbos that would be reasonably well matched to the rx8. T618z would be on the small end. I currently have what would nominally be a 620.
My constraints are these:
1) I would like to install it at the exhaust ports.
2) An external wg is not a problem. (Though I would rather not incur the extra expense.)
3) Ballbearing, water-cooled unit is a major plus.
4) Spin up no sooner than 4250 rpm and no later than 5000.
5) Flows somewhere north of 300g/sec or 40#/min at >70% eff. and 14psi, but less than 500g/sec-65#/min.
6) Can include any make, model that can be accessed off-the-shelf.
As usual, if you dont know what the **** you are talking about, please keep it to yourself.
I am looking for a list of possible, off the shelf turbos that would be reasonably well matched to the rx8. T618z would be on the small end. I currently have what would nominally be a 620.
My constraints are these:
1) I would like to install it at the exhaust ports.
2) An external wg is not a problem. (Though I would rather not incur the extra expense.)
3) Ballbearing, water-cooled unit is a major plus.
4) Spin up no sooner than 4250 rpm and no later than 5000.
5) Flows somewhere north of 300g/sec or 40#/min at >70% eff. and 14psi, but less than 500g/sec-65#/min.
6) Can include any make, model that can be accessed off-the-shelf.
As usual, if you dont know what the **** you are talking about, please keep it to yourself.
12-03-2010, 09:49 PM
#4
U-Stink-But-I-♥-U
Thread Starter
iTrader: (1)
Join Date: Mar 2005
Location: 12 o'clock on the Beltway.
Posts: 2,004
Likes: 0
Received 1 Like
on
1 Post
Brettus, that is number one on my list, but I was hoping for a little lessonage in HKS, turbonetics and others.
I am really not interested in a top mount. I want it as close as possible to the exhaust ports as per 1) on my list.
I am really not interested in a top mount. I want it as close as possible to the exhaust ports as per 1) on my list.
12-04-2010, 01:57 AM
#6
the Garrett website has a decent tutorial for beginners
GTX3076R
otherwise if you insist on the Greddy position quietly wait for MM to finish your 2+ year old Greddy upgrade, but if you cant wait then BNR also has a Greddy upgrade, same make as the original but a hybrid I believe
GTX3076R
otherwise if you insist on the Greddy position quietly wait for MM to finish your 2+ year old Greddy upgrade, but if you cant wait then BNR also has a Greddy upgrade, same make as the original but a hybrid I believe
Last edited by TeamRX8; 12-04-2010 at 02:03 AM.
12-04-2010, 04:17 PM
#8
U-Stink-But-I-♥-U
Thread Starter
iTrader: (1)
Join Date: Mar 2005
Location: 12 o'clock on the Beltway.
Posts: 2,004
Likes: 0
Received 1 Like
on
1 Post
Team: Read it already and as I said, I have the gtx3076r on top of my list. I am looking for pro/cons on other manufacturers.
How long would you have me wait? 2 more years? I dont think so.
Brettus: I will do detailed measurements wen it is off the car.
How long would you have me wait? 2 more years? I dont think so.
Brettus: I will do detailed measurements wen it is off the car.
12-04-2010, 11:15 PM
#9
Registered User
Join Date: Feb 2010
Posts: 72
Likes: 0
Received 0 Likes
on
0 Posts
http://www.turblown.net/store/index.php?productID=248
with this turbine housing;
http://www.turblown.net/store/index.php?productID=229
and this compressor housing upgrade;
http://www.turblown.net/store/index.php?productID=127
with this turbine housing;
http://www.turblown.net/store/index.php?productID=229
and this compressor housing upgrade;
http://www.turblown.net/store/index.php?productID=127
12-06-2010, 09:25 PM
#12
U-Stink-But-I-♥-U
Thread Starter
iTrader: (1)
Join Date: Mar 2005
Location: 12 o'clock on the Beltway.
Posts: 2,004
Likes: 0
Received 1 Like
on
1 Post
Essentially, yes. I have a bit of latitude in that regard, but for the most part, this is where I would like it to go.
I had a little time to do some reading today with regard to picking a proper turbo for the application. I am starting with two general requirements. Quick spool-up (, i.e., usable on-boost at not much more than 4250rpm), good auc on a torque v rpm plot and good hp numbers at high rpm, perhaps upwards of 400hp. Use will be both street and track so peaky hp/ torque is to be somewhat avoided.
Using a conservative estimate of 8hp/lbs/min and shooting for 50lbs/min, the gtx3076r might just be able to reach that at 70% eff and 14psi. Taking the next step up into the 35 range, flow jumps a bundle and the turbine plot of turbine flow v press ratio (not the compressor map) suggests (maybe, if I am reading it right) that I would find it difficult to spin as early as I wish to.
I think what I am looking for is something that can still be wrapped in a t3 housing, spin as quickly as a 3076 but flow just a tad more than what the 3076 does.
I had a little time to do some reading today with regard to picking a proper turbo for the application. I am starting with two general requirements. Quick spool-up (, i.e., usable on-boost at not much more than 4250rpm), good auc on a torque v rpm plot and good hp numbers at high rpm, perhaps upwards of 400hp. Use will be both street and track so peaky hp/ torque is to be somewhat avoided.
Using a conservative estimate of 8hp/lbs/min and shooting for 50lbs/min, the gtx3076r might just be able to reach that at 70% eff and 14psi. Taking the next step up into the 35 range, flow jumps a bundle and the turbine plot of turbine flow v press ratio (not the compressor map) suggests (maybe, if I am reading it right) that I would find it difficult to spin as early as I wish to.
I think what I am looking for is something that can still be wrapped in a t3 housing, spin as quickly as a 3076 but flow just a tad more than what the 3076 does.
12-06-2010, 09:49 PM
#13
sounds to me like you're looking for a hybrid close to what I'm running on my mirage...check these guys out:
click here
look at the T3/T4 stage 3 with the .48 a/r exhaust side. That's the exact one I have on my mirage. Insane little turbo! It swears that it's a GT30...I just go with it because I don't want to hurt the turbo's feelings. haha Of course, they have other sizes. that company has decent turbos for just about any need. Not to mention the pricing is fairly decent. I haven't had a problem to date with that little guy.
click here
look at the T3/T4 stage 3 with the .48 a/r exhaust side. That's the exact one I have on my mirage. Insane little turbo! It swears that it's a GT30...I just go with it because I don't want to hurt the turbo's feelings. haha Of course, they have other sizes. that company has decent turbos for just about any need. Not to mention the pricing is fairly decent. I haven't had a problem to date with that little guy.
12-07-2010, 12:09 PM
#15
U-Stink-But-I-♥-U
Thread Starter
iTrader: (1)
Join Date: Mar 2005
Location: 12 o'clock on the Beltway.
Posts: 2,004
Likes: 0
Received 1 Like
on
1 Post
Also, besides surge and lag, what are the downsides of having too much turbo?
Take a look at the compressor map of the GT3582R. To me, it looks only slightly oversized, but very close to what I would want. Is it? Can I estimate spool up from calculating estimated/normalized exhaust flow at 4000rpm (same as unboosted intake at 4000rpm normalized to temp) using their turbine plot?
The way I figure it, the GTX3582R gives me exactly what I want. Reasonably quick spool up if Kane is correct that the 35 turbine is not so overly large that it lags, but also pushes plenty of air at high eff. I am thinking perhaps this is the one to go with.
Anyone want to argue with me??
12-07-2010, 12:20 PM
#17
1/Do you have the fabrication skills to make it happen ?
2/Alternatively are you prepared to spend a bucket load on someone who does ?
3/Do you have the mechanical skills to follow thropugh with trouble shooting etc once it is fitted
4/see 2 again
5/Do you have the tuning skills to get the best out of it or are you prepared to learn from someone that does ?
If answer is no to any of the above then the exercise will end up like practically every other similar projet we have seen on this forum ..............
2/Alternatively are you prepared to spend a bucket load on someone who does ?
3/Do you have the mechanical skills to follow thropugh with trouble shooting etc once it is fitted
4/see 2 again
5/Do you have the tuning skills to get the best out of it or are you prepared to learn from someone that does ?
If answer is no to any of the above then the exercise will end up like practically every other similar projet we have seen on this forum ..............
12-07-2010, 12:24 PM
#18
U-Stink-But-I-♥-U
Thread Starter
iTrader: (1)
Join Date: Mar 2005
Location: 12 o'clock on the Beltway.
Posts: 2,004
Likes: 0
Received 1 Like
on
1 Post
1) I do not. Car is getting shipped today to someone that does.
2) Bucketload? Define.
3) To an extent. It should be pretty worked though when I get it back and there will be considerable help from the mech that did the install.
4) Again, define. And two whom are you refering in this case?
5) To an extent. It should be pretty worked through when I get it back.
This is going to happen. It is going to be a very interesting build. Trust me on that.
Kane. WHen you say big boy, are you refering to the compressor? The turbine fits in a t3 housing, which should fit. I am not sure how to pick the compressor however.
2) Bucketload? Define.
3) To an extent. It should be pretty worked though when I get it back and there will be considerable help from the mech that did the install.
4) Again, define. And two whom are you refering in this case?
5) To an extent. It should be pretty worked through when I get it back.
This is going to happen. It is going to be a very interesting build. Trust me on that.
Kane. WHen you say big boy, are you refering to the compressor? The turbine fits in a t3 housing, which should fit. I am not sure how to pick the compressor however.
12-08-2010, 02:37 AM
#19
anything is possible given the fabrication.
the GTX3582R has a huge compressor housing. with a low mount it will probably require a custom motor mount to provide extra clearance.
regardless, the GTX3582R does sound like it would suit your needs and constraints 3, 4, and 5.
the GTX3582R has a huge compressor housing. with a low mount it will probably require a custom motor mount to provide extra clearance.
regardless, the GTX3582R does sound like it would suit your needs and constraints 3, 4, and 5.
12-08-2010, 04:25 AM
#21
1) I do not. Car is getting shipped today to someone that does.
2) Bucketload? Define.
3) To an extent. It should be pretty worked though when I get it back and there will be considerable help from the mech that did the install.
4) Again, define. And two whom are you refering in this case?
5) To an extent. It should be pretty worked through when I get it back.
This is going to happen. It is going to be a very interesting build. Trust me on that.
Kane. WHen you say big boy, are you refering to the compressor? The turbine fits in a t3 housing, which should fit. I am not sure how to pick the compressor however.
2) Bucketload? Define.
3) To an extent. It should be pretty worked though when I get it back and there will be considerable help from the mech that did the install.
4) Again, define. And two whom are you refering in this case?
5) To an extent. It should be pretty worked through when I get it back.
This is going to happen. It is going to be a very interesting build. Trust me on that.
Kane. WHen you say big boy, are you refering to the compressor? The turbine fits in a t3 housing, which should fit. I am not sure how to pick the compressor however.
12-08-2010, 04:37 PM
#22
U-Stink-But-I-♥-U
Thread Starter
iTrader: (1)
Join Date: Mar 2005
Location: 12 o'clock on the Beltway.
Posts: 2,004
Likes: 0
Received 1 Like
on
1 Post
ALright. I think I have settled on one that meets my needs! Might actually flow as good or better than the GTX3582, but the GTX3582 itself doesn't look like it will fit my application (at least not at the exhaust ports. Might be fine otherwise.)
Thanks all for your help!!!!
Thanks all for your help!!!!
