This thing is going to need more air than previously thought. So here I go into ITB land. Looking at some 4AG stuff right now, any thoughts?
101MM Stroke 7MGE
- Thread starter DEFIANT 7M
- Start date
Or maybe convert the lower intake like these.
http://www.redlineweber.com/html/throttle_bodies/Throttle bodies_side_mount.htm
http://www.redlineweber.com/html/throttle_bodies/Throttle bodies_side_mount.htm
nice job. but you know what, i thought the 7m head has some combustion problems above 12.5cr how did you overcome this as 15:1 would cause a lot of detonation. the bowl shape is just to small to support this type of cr. on a side note (titanmotorsports) has a 7m head well worth looking at, it requires the use of your supplied cams and costs about 3500.00 but it might be able to help with itb's if your going that route.
oh yeah and to siman. the itb's along with the 15:1 would only be useful on the top end as you would need crazy cams to to keep any type of air in the engine.
Have not heard or seen anything on the 7M combustion chambers not able to handle high compression (above 12.5). Also if it were not feasible we would not even try this stunt. We have well over 100hrs. in this head with extensive flow bench testing to see what works. Titan has a nice head, but I would put mine up against them any day. Also my cams will demand ITBs with 12.5mm lift (.492) and 264 duration @ .50PHILLYSUPRA said:
So you from Philly? Born and raised myself left @ 12, we moved to Miami.
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first, naw born in ga moved to philly when i was 7. oh and i read from the toysport.com site on 7m modifications that it cannot be done. but.......... if you have done it and it works then i guess you're right and ill take it as that and i learned something new. what you have done has sparked a lot of ideas though, keep us updated. oh yeah todaracing.com has some good lift cams for that app. i think toda has 302 duration plus a bunch other i cant remember now.
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Adjuster
Supramania Contributor
Nice to see this thread back on the SM.
Hope to see your 101mm stroker running soon Alan.
My 97mm one has survived a trip to Portland from Boise, and some 1000 miles now of running around pretty much untuned. (On good gas.)
Sounds like nothing else out there. (Very much a diesel truck lurking under my hood.) However, on the top end at 6K+ it's just mean sounding.
Dyno numbers from the Portland NWPac Supra's meet this past weekend were mixed. I made less top end, but could not get this cold motor to stop fuel cut due to too much Karmann Hz going to the TCCS. (Just running a piggyback Eman on the stock ECU.)
The good news is higher tourqe numbers at this lower boost level than I've ever seen yet.
How does 413.90 at about 3850rpm sound? (This was at 15lbs of boost per the Omori gauge peak, but I have no idea what the actual boost level was at that time, but close to 15psi is a good guess.) Best HP number it could muster was 372rwhp. But remember this was with the engine hitting fuel cut 3 times during the run.
IIRC, the old engine, on stock stroke and bore was about 420rwhp and 360's tourqe at 18psi.
I'm hoping to see the tourqe break 475 or even 500ft lbs, and rwhp levels in the mid 500's would be very nice indeed. (Especially when you consider this is a 60 trim bolt on T4 turbo running the stock exhaust manifold, and ITS built Turbonetics sourced CT type housing.)
Engine right now is rich off the scale as the boost comes on line fully. (Nice 12:1 line from throttle tip in to about 3500rpm, but then goes rich, so I'll have to tune out some fuel adjustment up there.)
BTW, that dry sump oil pan is very nice. I'd mount your sump like you plan where the battery goes. I ended up mounting my Canton filter on the right apron, and only had to drill one hole to mount the 4 bolts. (Used 3 stock captured nuts, they just worked out perfect.) I've managed to retain PS, and AC on this car too, so it's fun to cruise around, even in very hot weather.
I'm interested to see how that Holly EFI works out. I'm looking at various ways of improving my ECU setup, and either going with the new Greddy unit, or a full stand alone might be in the works one of these days.
Last, the BBC inner springs are working great. I've actually recorded a 7190rpm peak with no problems on this car. (Missed a shift I suppose, but found myself bouncing off the rev limiter at the track, and on the street if I'm not paying attention, it's that smooth at high RPM.) Also the tourqe breaks the tires loose, and your hitting the rev limiter before you know it.
Good luck on getting your even larger 7M going, and let us know about the harmonic dampeners. I'm also concerned about this on my engine, and with the right setup, this is a good mod for sure. (Especially if they machine a crank trigger into the part.... No more CPS would be fine with the right standalone ECU.)
Hope to see your 101mm stroker running soon Alan.
My 97mm one has survived a trip to Portland from Boise, and some 1000 miles now of running around pretty much untuned. (On good gas.)
Sounds like nothing else out there. (Very much a diesel truck lurking under my hood.) However, on the top end at 6K+ it's just mean sounding.
Dyno numbers from the Portland NWPac Supra's meet this past weekend were mixed. I made less top end, but could not get this cold motor to stop fuel cut due to too much Karmann Hz going to the TCCS. (Just running a piggyback Eman on the stock ECU.)
The good news is higher tourqe numbers at this lower boost level than I've ever seen yet.
How does 413.90 at about 3850rpm sound? (This was at 15lbs of boost per the Omori gauge peak, but I have no idea what the actual boost level was at that time, but close to 15psi is a good guess.) Best HP number it could muster was 372rwhp. But remember this was with the engine hitting fuel cut 3 times during the run.
IIRC, the old engine, on stock stroke and bore was about 420rwhp and 360's tourqe at 18psi.
I'm hoping to see the tourqe break 475 or even 500ft lbs, and rwhp levels in the mid 500's would be very nice indeed. (Especially when you consider this is a 60 trim bolt on T4 turbo running the stock exhaust manifold, and ITS built Turbonetics sourced CT type housing.)
Engine right now is rich off the scale as the boost comes on line fully. (Nice 12:1 line from throttle tip in to about 3500rpm, but then goes rich, so I'll have to tune out some fuel adjustment up there.)
BTW, that dry sump oil pan is very nice. I'd mount your sump like you plan where the battery goes. I ended up mounting my Canton filter on the right apron, and only had to drill one hole to mount the 4 bolts. (Used 3 stock captured nuts, they just worked out perfect.) I've managed to retain PS, and AC on this car too, so it's fun to cruise around, even in very hot weather.
I'm interested to see how that Holly EFI works out. I'm looking at various ways of improving my ECU setup, and either going with the new Greddy unit, or a full stand alone might be in the works one of these days.
Last, the BBC inner springs are working great. I've actually recorded a 7190rpm peak with no problems on this car. (Missed a shift I suppose, but found myself bouncing off the rev limiter at the track, and on the street if I'm not paying attention, it's that smooth at high RPM.) Also the tourqe breaks the tires loose, and your hitting the rev limiter before you know it.
Good luck on getting your even larger 7M going, and let us know about the harmonic dampeners. I'm also concerned about this on my engine, and with the right setup, this is a good mod for sure. (Especially if they machine a crank trigger into the part.... No more CPS would be fine with the right standalone ECU.)
Going to go with the 4AGE 20V throttle bodies. Working everything out as we speak. I'll add to it when I know more
Since I'm going with the 20V ITBs here is a good thread to check out. The 4AGE guys got some hardcore stuff!!
http://forums.club4ag.com/topic.asp?TOPIC_ID=95830
http://forums.club4ag.com/topic.asp?TOPIC_ID=95830
The "Silver" top 20V uses a 43mm throttle body. The "Black" top 20V uses a 45mm throttle body. Here is some good basic info from the Jenvey site.
What is the best throttle body diameter?
Factors influencing size are; Power output, RPM, cylinder head design, cylinder capacity, position of the throttle body in the inlet tract and position of the injector.
Choice of bore size is a balanced compromise resulting from the following;
1) A larger bore leads to lower flow resistance, but obeying the laws of diminishing returns.
2) A smaller bore leads to better throttle control and response (never underestimate) and improved fuel mixing.
3) The system should be considered in total - from (at least) trumpet flange to cylinder and proportioned accordingly.
Basic references for BHP per cylinder, assuming ca 120mm from butterfly to valve head and a max of 9,000 rpm are;
Up to 30 - 30mm, up to 33 - 32mm, up to 39 - 35mm, up to 46 - 38mm, up to 51 - 40mm, up to 56 - 42mm
Up to 65 - 45mm, up to 74 - 48mm, up to 80 - 50mm, up to 87 - 52mm, up to 93 - 54mm.
These power figures may be increased by up to 10% in a purpose - designed and well proportioned system.
As butterfly to valve distance increases, butterfly size will need to increase in proportion to system taper and vice versa.
Lower revving engines and those with injectors placed before the butterfly will generally accept a larger body.
What is the best throttle body diameter?
Factors influencing size are; Power output, RPM, cylinder head design, cylinder capacity, position of the throttle body in the inlet tract and position of the injector.
Choice of bore size is a balanced compromise resulting from the following;
1) A larger bore leads to lower flow resistance, but obeying the laws of diminishing returns.
2) A smaller bore leads to better throttle control and response (never underestimate) and improved fuel mixing.
3) The system should be considered in total - from (at least) trumpet flange to cylinder and proportioned accordingly.
Basic references for BHP per cylinder, assuming ca 120mm from butterfly to valve head and a max of 9,000 rpm are;
Up to 30 - 30mm, up to 33 - 32mm, up to 39 - 35mm, up to 46 - 38mm, up to 51 - 40mm, up to 56 - 42mm
Up to 65 - 45mm, up to 74 - 48mm, up to 80 - 50mm, up to 87 - 52mm, up to 93 - 54mm.
These power figures may be increased by up to 10% in a purpose - designed and well proportioned system.
As butterfly to valve distance increases, butterfly size will need to increase in proportion to system taper and vice versa.
Lower revving engines and those with injectors placed before the butterfly will generally accept a larger body.
Back from the dead!! Update: I was going to use ITBs from a 20V, but Arnout has come thru for me again! :icon_bigg I should have the ITBs and surge tank with a custom flange from a RB26 Skyline very soon.
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As it sits yes. Once I get it I'll see what modifications need to be done. We may do away with the surge tank not sure.IHI-RHC7 said:
Allan: What happens with the port spacing?
I guess it depends on where you graft it onto the 7M intake.
I guess it depends on where you graft it onto the 7M intake.
Good question IJ
I am curious too. I thought about this many times and would love to know what really is involved to do something with those ITBS off of the RB26.
Also are you planning on controling the throtles individually as well? To fine tune for each Cylinder.
I am curious too. I thought about this many times and would love to know what really is involved to do something with those ITBS off of the RB26.
Also are you planning on controling the throtles individually as well? To fine tune for each Cylinder.
yeah, either get rid of the surge tank or have a new one made. can it be unbolted and flipped over to bolt on correctly since even the itbs are going to be on back wards in a sense?DEFIANT 7M said:
ive been mia for sometime... missed out on following this thread but now that ive read most of these 15 pages im hooked... awesome work and good job sharing it all.. GOOD LUCK!!! Get er runnin!! Ill be following from now on
Toycoma said:
the tank is part of the tb's themselves, so I say he should chop the tank and go sidedraft itbs.
speaking of sidedraft itb's...
Had to put it on hold a lot of things going on. Got my taste back while helping my brother with his car. As you know I don't do anything normal:biglaugh:http://www.accordinglydone.com/forum/showthread.php?t=11705 Yes it's a Honda!!supra90turbo said: