| Page: |
| Home > Technical Chat > Airflow for the turbo metro? | |||||||
 274 Posts Member #: 1174 Senior Member Sunny Southern California, USA |
4th Jan, 2007 at 06:28:01am
Ok. I'm thinking about having a custom intercooler built for my engine (www.bellintercoolers.com). To do it correctly I need to know the airflow for the turbo 1275.
Edited by Lance Link on 4th Jan, 2007. 61 Austin Seven; building a 1275 'over the clutch' turbo, R5 T2'd, custom intercooled, megajolt electrified, canyon carver
|
||||||
|
141 Posts Member #: 954 Advanced Member Fort Collins Colorado USA |
5th Jan, 2007 at 02:16:07am
Your caculation is right on for normally aspirated, and your thinking about volume is right too, but...
1275 with Back Door Turbo |
||||||
|
274 Posts Member #: 1174 Senior Member Sunny Southern California, USA |
5th Jan, 2007 at 02:59:12am
Hey fortfun. I know you from the MM forum! I'm known as Cheese~ over there.
61 Austin Seven; building a 1275 'over the clutch' turbo, R5 T2'd, custom intercooled, megajolt electrified, canyon carver
|
||||||
 2514 Posts Member #: 1217 I like nice quiet girly Minis Cheltenham, Gloucestershire |
5th Jan, 2007 at 07:13:00am
You need to size for where you want to end up, not where you start .... stock 1275 turbo unit gives around 94 bhp so would need 140ish cfm using 1.4ish Every day is a school day ...........
On 27th of Sep, 2007 at 12:45pm Jimster said:
why do you you think I got a girlfriend with small hands? |
||||||
|
3594 Posts Member #: 655 Post Whore Northern Ireland |
5th Jan, 2007 at 04:53:08pm
Dont most IC people size their cores based on a rough horsepower goal ?? 9.85 @ 145mph
|
||||||
|
274 Posts Member #: 1174 Senior Member Sunny Southern California, USA |
6th Jan, 2007 at 01:16:52am
On 5th of Jan, 2007 at 04:53pm stevieturbo said:
Dont most IC people size their cores based on a rough horsepower goal ?? It looks to me like most of the people around here are not doing this. Most of them seem to be choosing their intercoolers based upon what is available at the local scrap yard and what fits. Edited by Lance Link on 6th Jan, 2007. 61 Austin Seven; building a 1275 'over the clutch' turbo, R5 T2'd, custom intercooled, megajolt electrified, canyon carver
|
||||||
|
274 Posts Member #: 1174 Senior Member Sunny Southern California, USA |
6th Jan, 2007 at 01:19:11am
Sorry. I don't mean to sound thick. What I was outlining in one of my previous posts was that the 1.4cfm/hp guesstimate number didn't seem to match up with an actual airflow calculation for a given motor (in this case a na 1275). And before applying that calculation to my turbo motor, I wanted to understand it better.
61 Austin Seven; building a 1275 'over the clutch' turbo, R5 T2'd, custom intercooled, megajolt electrified, canyon carver
|
||||||
|
141 Posts Member #: 954 Advanced Member Fort Collins Colorado USA |
6th Jan, 2007 at 02:41:31am
Your engine pulling 150CFM would be making 110+ HP. Your 150CFM calculatoin assumed 100% volumetric efficiency, and that is tough to achieve with a naturally aspirated engine with streetable cam and exhaust.
1275 with Back Door Turbo |
||||||
|
2514 Posts Member #: 1217 I like nice quiet girly Minis Cheltenham, Gloucestershire |
6th Jan, 2007 at 10:23:59am
Some of us do look at the max air-flow, can't see the likes of TD, Jimster, Turbo Tim, Nic etc. just plonking it on because they had it.
Every day is a school day ...........
On 27th of Sep, 2007 at 12:45pm Jimster said:
why do you you think I got a girlfriend with small hands? |
||||||
|
4314 Posts Member #: 700 Formerly British Open Classic The West Country |
6th Jan, 2007 at 12:19:57pm
About a year ago Robert did some air flow testing of existing intercoolers:
Isambard Kingdom Brunel said:
Nothing is impossible if you are an Engineer |
||||||
|
274 Posts Member #: 1174 Senior Member Sunny Southern California, USA |
6th Jan, 2007 at 07:32:00pm
Thanks guys. I appreciate the info.
Edited by Lance Link on 6th Jan, 2007. 61 Austin Seven; building a 1275 'over the clutch' turbo, R5 T2'd, custom intercooled, megajolt electrified, canyon carver
|
||||||
|
274 Posts Member #: 1174 Senior Member Sunny Southern California, USA |
6th Jan, 2007 at 07:36:56pm
On 6th of Jan, 2007 at 02:41am fortfun said:
Your 150CFM calculatoin assumed 100% volumetric efficiency, and that is tough to achieve with a naturally aspirated engine with streetable cam and exhaust. As I was suspecting, this would then account for the difference between the calculation methods. Thanks! 61 Austin Seven; building a 1275 'over the clutch' turbo, R5 T2'd, custom intercooled, megajolt electrified, canyon carver
|
||||||
|
3594 Posts Member #: 655 Post Whore Northern Ireland |
6th Jan, 2007 at 07:48:41pm
On 6th of Jan, 2007 at 07:32pm Lance Link said:
Thanks guys. I appreciate the info. If a person were to install an oversized intercooler, like the cossie one, wouldn't all that excess capacity add to the lag when trying to build boost? Or is it infinitesimal when compared to a smaller, more closely matched intercooler? It looks like the one I'm speccing out will be capable of flowing 200hp. Since I'm only looking for 130-140hp, it should be ok. I personally think, you would need a HUGE intercooler, for any apparent "lag" to be noticeble. I dont think it would be physically possible to fit an intercooler so big, that it would become an issue on a mini ( unless you mount it in a silly place lol ) 9.85 @ 145mph
|
||||||
|
2514 Posts Member #: 1217 I like nice quiet girly Minis Cheltenham, Gloucestershire |
6th Jan, 2007 at 09:04:39pm
Roof mounted intercooler anybody ......
Every day is a school day ...........
On 27th of Sep, 2007 at 12:45pm Jimster said:
why do you you think I got a girlfriend with small hands? |
||||||
| Home > Technical Chat > Airflow for the turbo metro? | |||||||
|
|||||||
| Page: |