Project 200whp N/A
#181
...
The square top flows well up to about 175whp N/A or well past that F/I. Eventually it runs out of CFM even though the lengths and diameters are almost perfect. Better internal shaping and flow than the USDM VICS (NB1) and VTCS (NB2) but still along way from awesome.
...
The square top flows well up to about 175whp N/A or well past that F/I. Eventually it runs out of CFM even though the lengths and diameters are almost perfect. Better internal shaping and flow than the USDM VICS (NB1) and VTCS (NB2) but still along way from awesome.
...
Edelbrock Mustang TB hackjob:
#182
If you compare a Murha and a Maxim the primaries and secondaies are the same dimeter the collector is larger 60mm and the routing of the pipes are nearly the same its just got the 50mm venturi and split construction that really distinguish it from the Maxim.
My class doesn't allow as much modification as what you are doing with your engines I have to have a stock long block or at least one built within the guidelines of the factory manual and a stock intake and throttle body and this is why I kinda of think that the Maxim might be more optimum for my application. If I was running an elevated redline and making more power I wouldn't hesitate to get the RB. I guess I was just looking to see if anyone else might agree that having higher exhaust velocity due to a smaller collector and catback would be more optimum for my more limited level of prep.
Last edited by speedingbolt; 02-18-2014 at 03:24 PM.
#183
If I was running an elevated redline and making more power I wouldn't hesitate to get the RB. I guess I was just looking to see if anyone else might agree that having higher exhaust velocity due to a smaller collector and catback would be more optimum for my more limited level of prep.
I assume your question is "have you observed any gains with the square top after adding a bigger TB ?
Nope. Above about 170whp we could just barely see a repeatable 2whp at very high rpm. That's an annoying A/B/A test. Do the math on flow. Stock TB flows enough for about 250whp N/A. F/I is a different matter and we have done no testing with TB's there at all. The math indicates there will start to be gains above 250whp F/I with a bigger TB. So test it and report back if you would please
__________________
#186
Our shfancy 2.0L build has seen several delays. The last was a machine shop accidentally removing some of the head coatings. Fun stuff. Anyway, it's back on track and we're told the long block will finally arrive here next week.
Anyway, I wanted to repost this dyno plot of Crushers 2013 nationals motor done back in September 2013. For reference, this was done with 1861cc and 10.4:1 compression, no coatings.
More details in this thread https://www.miataturbo.net/race-prep...7/#post1049820
Anyway, I wanted to repost this dyno plot of Crushers 2013 nationals motor done back in September 2013. For reference, this was done with 1861cc and 10.4:1 compression, no coatings.
More details in this thread https://www.miataturbo.net/race-prep...7/#post1049820
__________________
Last edited by emilio700; 04-03-2014 at 03:37 PM.
#189
2.0 Whammy
Motor arrived a few days ago. Finally got around to taking (bad) pictures.
We have had some change of plans for our project cars so this engine may end up going into a different car. Maybe the 95R? It could really use a dry sump or at least a vacuum pump but I wanted to build something that was a bit more within the reach of the average Miata enthusiast. Thus the wet sump. Dry sumps start at around $2500 and are not street car friendly.
13.0:1
1952cc
Coated chambers, exhaust ports and valves
.450 lift cams
+2mm CNC head
It will burn E85, run on an MS3Pro with sequential fuel and spark as well as individual cylinder trim for fuel/spark. 36T wheel
We anticipate it will just touch 200whp with a square top, which hasn't been done AFAIK. 215whp or so with the same ITB's we ran at 2013 NASA nationals. We made 191whp then on 1861cc 10.2:1 bottom end, no coatings and smaller cams.
We have had some change of plans for our project cars so this engine may end up going into a different car. Maybe the 95R? It could really use a dry sump or at least a vacuum pump but I wanted to build something that was a bit more within the reach of the average Miata enthusiast. Thus the wet sump. Dry sumps start at around $2500 and are not street car friendly.
13.0:1
1952cc
Coated chambers, exhaust ports and valves
.450 lift cams
+2mm CNC head
It will burn E85, run on an MS3Pro with sequential fuel and spark as well as individual cylinder trim for fuel/spark. 36T wheel
We anticipate it will just touch 200whp with a square top, which hasn't been done AFAIK. 215whp or so with the same ITB's we ran at 2013 NASA nationals. We made 191whp then on 1861cc 10.2:1 bottom end, no coatings and smaller cams.
__________________
Last edited by emilio700; 04-17-2014 at 01:39 AM.
#192
Moderator
iTrader: (12)
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 20,650
Total Cats: 3,011
That's almost as much CR as people run on circle track small block Chevys that came to market in 1955. I'm saying without any real knowledge about what I am talking about (other than knowing people who race) that I think there might be even more room for growth. If you are on race fuel, why not push for a 14 or 15 CR?
#193
That's almost as much CR as people run on circle track small block Chevys that came to market in 1955. I'm saying without any real knowledge about what I am talking about (other than knowing people who race) that I think there might be even more room for growth. If you are on race fuel, why not push for a 14 or 15 CR?
Last edited by emilio700; 04-17-2014 at 12:38 AM.
#199
Elite Member
iTrader: (8)
Join Date: Dec 2008
Location: Kingston, Ontario
Posts: 2,910
Total Cats: 51
Nice setup.
Similar to the engine package I plan to put together for my Miata.
Though I wont be using coatings and I don't know what I'm doing with valves or cams yet. I will be using a custom intake manifold design that will be dyno optimized for power band... not ITB's.
Similar to the engine package I plan to put together for my Miata.
Though I wont be using coatings and I don't know what I'm doing with valves or cams yet. I will be using a custom intake manifold design that will be dyno optimized for power band... not ITB's.
#200
Packaging, cost. Oil tank is usually 18-22" tall x 6" diameter. Engine is built differently from the start. In my view, dry sump is sort of the last step in an N/A build to a full race only engine. If I were doing a dry sump, it would have .500 lift cams and 15:1 CR. But I have no use for such an grenade engine.
This engine was built with the intention of being used on the street. Thus, only .450 lift, way less duration than even a 185whp EP engine uses, wet sump. As mentioned before, the dry sump is a significant barrier to entry for most builders both from implementation and cost perspectives. Only a handful of shops around the country that know their way around a Miata dry sump (Prather, ARE, et,al). You would have to pay those guys to get your system right, or gamble with a $15k race motor. We always want the projects we do to have some real world relevance, trickle down the tech. 200whp with semi streetable cams and a wet sump. Possible..
EP dry sump
This engine was built with the intention of being used on the street. Thus, only .450 lift, way less duration than even a 185whp EP engine uses, wet sump. As mentioned before, the dry sump is a significant barrier to entry for most builders both from implementation and cost perspectives. Only a handful of shops around the country that know their way around a Miata dry sump (Prather, ARE, et,al). You would have to pay those guys to get your system right, or gamble with a $15k race motor. We always want the projects we do to have some real world relevance, trickle down the tech. 200whp with semi streetable cams and a wet sump. Possible..
EP dry sump
__________________