Gerg_R31
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Posts posted by Gerg_R31
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i am well aware of the shorter runners = more top end,
longer runners = more bottom end
unfortunatly there is the physical room to fit them, which isnt available
then there is the linkage holder, which there is a bar that was welded onto the trumpets to support that
www.jntperformance.com.au this is where i have bought the ramtubes from, they do have bends and longer ramtubes etc
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They're coming pretty soon
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That was in reply to?
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Cleaning up the ports or de dagging removes restrictions
professional porting as in re shapping enlarging the right spots etc will increase a cfm flow best suit to the lift your chasing
my 26 head flows best at 0.420" lift,i couldn't go larger without affecting the air velocity which you can go larger with forced induction so 10.8mm lift works perfectly in mine cause the ports can flow up to that much lift, putting 11.3mm lift cams in would make me loose power cause the head doesn't flow at that lift
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Ported head?
If not the standard ports work better with 9mm (0.300"-0.350") lift after porting the heads can flow to suit bigger lift
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For the rb30 bottom end you will need longer duration on the exhaust,
Surecams are the only custom cam grinders left in nsw
And i doubt dirt garage has a cam grinder, a clue or even a qualification with some of the shit I've had to repair of his "handy work"
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Warped head will show symptoms of a blown head gasket
and lower compression in #3 & #4
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posting for updates
oh and other then the sr20 what other motors ended up in memphis?
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other then andrews previous post, all he has told me is the same and "he cant say anymore until the testing is completed"
in my opinion, with fewer details released, fewer people can under cut their r&d
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Rd blocks - unless your going full drag and intend to completely fill it, waste of time
head bolt holes line up, rb cranks fit fine
you will have to make sure 100% there is no diesel oil hidden anywhere
drain back holes don't line up
rear drain back on exhaust side of head won't have anything connected to it
water jackets don't line up
there is not enough material to relocate the tensioner in the right spot
casting is f**k all thicker
does have oil squirters
water pump, oil pump rear main seal housing fits any other rb parts
a spacer plate and sleeve job would be cheaper then an rd block
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take a read GTRNUR has done something similar to what your thinking
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small updates;
new seat
new dash
got new wheels
Got Flares
thursday night;
7:30pm trailing arms came out
old bushes next to new ones
8:30 trailing arms went back in
9pm leaving maccas
9:15 noticed dash was dull
9:20 car dies on cumberland highway, alternator belt had snapped
organised a spare
push car to start of right turning lane
notice slight bubbling noise from radiator
Pulled everything off to get ready to put new one on
Phone dies
numerous people stop to ask if i need help, only 1 dickhead
Many lols were had watching people getting caught by safety camera, i waved in a few (stolen idea from top gear)
So many morons still attempt to join the cue behind my car while im sitting on the boot
some even locked their brakes up cause they were too busy on phone to pay attention
spare belt turns up
cant access his battery
he persists in flagging down girls in hatch backs, 1 nearly successful
he calls a tow truck, he heads off as he has work,
girls come back, no jumper leads
11:30 tow truck turns up
11:31 tow trucks heater is awesome
11:40 home
11:45 batter and booster charging
6am reconnect battery alarm goes off, drains battery
8am buy new battery
8:10 off to Marulan
10am road works, didnt see entry after bridge, tom tom takes me down a dirt track
1pm i finally get off my butt and sign on
got 3 and a half sessions in, power steering belt kept coming off, and i got black flagged for exeeding noise limits (i stayed in 2nd as it picked up quicker and would nearly rev all the way out before the next turn)
http://www.youtube.com/watch?v=3Lr47p0gW1s
http://www.youtube.com/watch?v=_OLy2hh1ihk
got new power steering and water pump belts, got the shorter versions this time
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using it as a guide is still wrong, you know how many people argue that i cant have 10:75:1 because someone else has a dome thats bigger then the one on my piston?
but yeas, i agree there, that is another more correct method and that would be just as accurate as measuring everything before it is put together, X is your CV and Y is your SV+CV, they do that with alot of the race cars to make sure they are within spec of the rule book
using a burrette you can also measure a combustion chamber or an eye dropper if you dont have one 1mm = 1cc
same with the piston, if its a dome, use play dough
and you can actually measure the squash of a head gasket with the right measuring tools, average it is about 10 thou, but that is a guess i still wont use
lol shall we go into dynamic compression and volumetric efficency?
sorry about whoring your thread zach
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i will NOT agree in saying that to buy a piston based on its stated compression ratio will ever be true,
I will also NOT agree to use their tables, that is guessing, i will actually use measurements that i personally measure myself, this eliminates variables, which when a company says that it has too many variables it means "they have no clue they just bought them from someone else" or "check everything is right cause we just told you how we are not liable for you purchasing the wrong pistons if you dont measure everything"
the formula is used with measurements taken from the piston, block, head gasket and cylinder head that those pistons are going into, not just 1 item, not someone elses parts or measurements.
This is the only right way, its only "too many variables" if there is a lazy engine builder or a company avoiding liability, why spend big money to guess?
sure the pistons with the higher comp ratio stated might be true in saying it will be higher, thats still a guess as to how much higher
can you garantee the head chamber isnt 61cc's where it should be 64? or is it 68 instead?
1mm head gasket not available but a 1.8mm is?
piston sitting 10 thou above before its been ground during a dummy assemble, was it ground and tunnel bored before?
you measure and calculate your comp. dont read what is on the sheet in the box
with engine building your either precisely spot on or your wrong and something will f**k up eventually
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in my trade i need to know how to do things properly
piston manufacturers will state "x:1" compression similar to cam manufaturers saying stage or type cams
they assume your measurements and specs will match theirs
they also assume the person who assembles will measure it first
here is the actual formula in full
Swept Volume
Bore x Bore = Answer1
Answer1 ÷ 4 = Answer2
Answer2 x π (3.142) x stroke = Answer3
Answer3 ÷ 1000 = Swept Volume ( SV )
Compression Volume
Head CC +
Piston dome - / dish volume +
Deck height (piston below the deck)
Bore x Bore = Answer1
Answer1 ÷ 4 = Answer2
Answer2 x π (3.142) x block deck to piston crown measurement = Answer3
Answer3 ÷ 1000 = deck height volume
Deck height (piston above the deck)
piston measurement above top ring land x piston measurement above top ring land = Answer1
Answer1 ÷ 4 = Answer2
Answer2 x π (3.142) x block deck to piston crown measurement = Answer3
Answer3 ÷ 1000 = deck height volume
Gasket
Gasket Bore x Gasket Bore = Answer1
Answer1 ÷ 4 = Answer2
Answer2 x π (3.142) x Gasket thickness = Answer3
Answer3 ÷ 1000 = Gasket volume
The Maths
Head CC + gasket Volume + Piston dish Volume(- Piston dome volume ) + deck height (-if piston is above the deck)= CV
SV + CV + Answer
Answer ÷ CV = Compression ratio
Example
my motor
87 x 87 = 7,569
÷ 4 = 1,892.25
x 3.142 x 85 = 505,363.2075
÷ 1000 = 505.36321 (sv)
Head CC 53.4
Piston Dome -10cc
deck height, piston above
0.005" ÷ 0.03837 = 0.127
86.1 x 86.1 = 7413.21
÷ 4 = 1853.3025
x 3.142 x 0.127 = 739.53071
÷ 1000 = -0.73953
head gasket
88 x 88 = 7,744
÷ 4 = 1,936
x 3.142 x 1.5 = 9,124.368
÷1000 = +9.12437
53.4 + 9.12437 - 10 - 0.73953 = 51.78484 CV
51.78484 + 505.36321 = 557.14805
÷ 51.78484= 10.7589 aka 10.75:1
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the pistons dont make the compression ratio
bore x stroke = SV
piston to deck height + gasket bore x gasket thickness (+ piston dish/ valve releif) or (- piston dome) + chamber cc = CV
sv + cv ÷ vc = static compression ratio
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metal head gaskets need to have the right head and block finish for them to seal
the composite gaskets need a rougher surface so it has something to bite into
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I guess you're running on E85?
no e85 no boost
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i got 225 dry 235 wet with my 26/30,
10.75:1 comp with cams; 10.8mm lift 242/252 duration @ 0.050" lift
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Sounds like someone is still upset about their uncle loving them too much
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Mine currently makes just under 170kw, makes power all the way up to 8200
but since i have learned of new tricks which ill be doing and going e85 at same time
Thinking Of Buying An R35...key Differences Between My09, 10, 11 & 12?
in VR Series - R35 GTR, Juke-R
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i personally dislike the 35,
while it did impress me at first, then i found out how the entire car is a "throw away item"
(my personal experience working on these)
09, 10 have a shim over bucket cam follwer, 11 & 12 have a solid 1 piece bucket with a stem on the inside
the 09/10 cylinder heads IMO are better as you can get shims made up and generally you order them thicker for the intention to grind them to suit the clearance you want
the 11 & 12 you will need to have nissan make up the solid buckets to suit the valve protrusion, if you get the measurement 100% perfect and matches their measuring tools
the bores are plasma coated, cannot be rebored or even honed as the coating is only 2 thou thick, darton will be releasing a sleeve kit quite soon
cranks cant be ground either due to their coating, spin a bearing, buy a new crank