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'The Sleeper'
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491 Posts
Discussion Starter #1 (Edited)
I have a slight issue.

I am currently making peak power at the rev limter (8200 rpm).

The graph shows no sign of flattening off, but I obviously want to reach the peak power point or slightly past it.

Will I be OK to run to 9000 rpm with my setup...

SR20DE+T Engine Conversion (9:1 comp. ratio)
53J Block
ARP Mains Studs
'98 RRM 4 Counterweight Crankshaft
96J High Port Cylinder Head (decked 1.2mm + ported & polished)
ARP Cylinder Head Studs
1.1 mm Cometic MLS Head Gasket
SR20DET Pistons
Eagle ‘H’ Beam Conrods
A.R.P. Conrod Bolts
DET Crank Girdle
‘92 eGT Sump & Sump Pan
Modified Oil Pump
SR20DET Oil Pick-up
'92 eGT Fuel Rail
NISMO ‘Yellow’ Fuel Injectors (641cc @ 4 BAR)
FSE Adjustable Fuel Regulator
Walbro 255LPH High Pressure Fuel Pump
Powertech Fuel Pump Hotwire Kit
MSD Digital 6 Ignition System
NGK ’Iridium’ Grade 8 Spark Plugs
'92 eGT Distributor
'92 eGT Ignitor Chip
'92 eGT Ignition Coil
Mine’s ECU
Greddy E-Manage
Z32 MAF
HKS 'Superflow' Air Filter
SFS Silicone Hosing
O2 Induction Intake Manifold
Modified VZR N1 Throttle Body (70mm)
Garrett GT297153R Turbocharger (0.86A/R housing)
Wastegate Assembly Ported, Flowed & Modified By ‘AET Turbos’
Modified Wastegate Actuator (set @ 12 psi)
Modified Equal Length Tubular Exhaust Manifold
Custom 3” Downpipe
3” Short Side-exit Exhaust
Cobra 3” Silencer
AET Turbos FMIC
Stepped (2.25" - 3") IC Piping (HOT)
3" IC Piping (COLD)
Turbosmart Single Stage Boost Controller
Turbosmart Recirculating Valve
JWT S4 Camshafts (266 duration / 11.79 mm lift)
Ferrea Titanium Retainers
JWT HD Valve Springs
'92 eGT Sodium Filled Valves
HKS Adjustable Camshaft Sprockets
Greddy Rocker Arm Stoppers
Koyo Racing Radiator
NISMO 18.2 psi Radiator Cap
NISMO Thermostat
Unorthodox Racing Crankshaft Pulley
Unorthodox Racing Water Pump Pulley
Energy Suspension Polyurethane Engine Mounts
Greddy Oil Catch Tank
Fidanza Flywheel (8.8 lbs)

Run on 99 RON fuel (US equivilent of 94 octane).

I realise that this is a similar post to my last one, but it seemed to die off without any real positive reply or solution.

Thanks

Dave
 

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Registered
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953 Posts
So... does it have 9:1 compression or 8.5:1 compression?

Also, your head doesn't seem to be built enough for 9000rpm. I know your bottom end is kinda iffy, with those 4 counter weight cranks...

Just wondering, but why not get a bigger turbo with smaller A/R so you don't have to rev as high?
 

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'The Sleeper'
Joined
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491 Posts
Discussion Starter #3
9:1 compression

Why can't the valvetrain take it.

We know that the JWT prepped valvetrain is OK to 8600 rpm on C3's (Mike Kojima's testing), so surely with the less aggressive S4's, it should be OK.
 

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31 Posts
In my opinion, with the upgraded valvetrain (rocker arm stoppers, springs, retainers, ect. ect.) that the head itself has the potential to rev higher than 8200, I cannot comment on the bottom end though because I have no experience with the 4 counterweight cranks.

I'd say slowly rev higher and higher and see where the power starts dropping off. No need to jump straight to 9000 rpms right off the bat.
 

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'The Sleeper'
Joined
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491 Posts
Discussion Starter #5
9000 rpm was just an idea.

I may find that it makes peak at 8600 therefore would take the limiter to 8800 or something like that.
 

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agent camel toe
Joined
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9,396 Posts
I have a slight issue.

I am currently making peak power at the rev limter (8200 rpm).

The graph shows no sign of flattening off, but I obviously want to reach the peak power point or slightly past it.

Will I be OK to run to 9000 rpm with my setup...

SR20DE+T Engine Conversion (9:1 comp. ratio)
53J Block
ARP Mains Studs
'98 RRM 4 Counterweight Crankshaft
96J High Port Cylinder Head (decked 1.2mm + ported & polished)
ARP Cylinder Head Studs
1.1 mm Cometic MLS Head Gasket
SR20DET Pistons
Eagle ‘H’ Beam Conrods
A.R.P. Conrod Bolts
DET Crank Girdle
‘92 eGT Sump & Sump Pan
Modified Oil Pump
SR20DET Oil Pick-up
'92 eGT Fuel Rail
NISMO ‘Yellow’ Fuel Injectors (641cc @ 4 BAR)
FSE Adjustable Fuel Regulator
Walbro 255LPH High Pressure Fuel Pump
Powertech Fuel Pump Hotwire Kit
MSD Digital 6 Ignition System
NGK ’Iridium’ Grade 8 Spark Plugs
'92 eGT Distributor
'92 eGT Ignitor Chip
'92 eGT Ignition Coil
Mine’s ECU
Greddy E-Manage
Z32 MAF
HKS 'Superflow' Air Filter
SFS Silicone Hosing
O2 Induction Intake Manifold
Modified VZR N1 Throttle Body (70mm)
Garrett GT297153R Turbocharger (0.86A/R housing)
Wastegate Assembly Ported, Flowed & Modified By ‘AET Turbos’
Modified Wastegate Actuator (set @ 12 psi)
Modified Equal Length Tubular Exhaust Manifold
Custom 3” Downpipe
3” Short Side-exit Exhaust
Cobra 3” Silencer
AET Turbos FMIC
Stepped (2.25" - 3") IC Piping (HOT)
3" IC Piping (COLD)
Turbosmart Single Stage Boost Controller
Turbosmart Recirculating Valve
JWT S4 Camshafts (266 duration / 11.79 mm lift)
Ferrea Titanium Retainers
JWT HD Valve Springs
'92 eGT Sodium Filled Valves
HKS Adjustable Camshaft Sprockets
Greddy Rocker Arm Stoppers
Koyo Racing Radiator
NISMO 18.2 psi Radiator Cap
NISMO Thermostat
Unorthodox Racing Crankshaft Pulley
Unorthodox Racing Water Pump Pulley
Energy Suspension Polyurethane Engine Mounts
Greddy Oil Catch Tank
Fidanza Flywheel (8.8 lbs)

Run on 99 RON fuel (US equivilent of 94 octane).

I realise that this is a similar post to my last one, but it seemed to die off without any real positive reply or solution.

Thanks

Dave

thats a nice grocery list
 

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Me likes Big Ol Booties!
Joined
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1,160 Posts
In my opinion, with the upgraded valvetrain (rocker arm stoppers, springs, retainers, ect. ect.) that the head itself has the potential to rev higher than 8200, I cannot comment on the bottom end though because I have no experience with the 4 counterweight cranks.

I'd say slowly rev higher and higher and see where the power starts dropping off. No need to jump straight to 9000 rpms right off the bat.
Hey guy, please change ur sig, you want a B14, not B15.
 

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Registered
Joined
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1,005 Posts
Can you post the dyno sheet?
Thanks.
 

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P10 pro
Joined
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545 Posts
I have a slight issue.

I am currently making peak power at the rev limter (8200 rpm).

The graph shows no sign of flattening off, but I obviously want to reach the peak power point or slightly past it.

Will I be OK to run to 9000 rpm with my setup...
I don't see why not. Your power curve is even more impressive than a cammed VE.
 

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I drift Soarer
Joined
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259 Posts
if you have the regular sr20de/t crank it has a 86mm storke. if you do the numbers for it the max rpm you can safely run on it for prolonged periods of time is around 8700 rpm. after that point the piston speed become too high. you should not exceed 25m/s for piston speeds. if you get at sr16de crank it has a 62.7mm stroke(i think it close to that). when i did the math with the sr16ve crank you can rev 10200 rpm. formula 1 cars dont exceed 25m/s for piston speeds...neither should your engine. to safely run to 8700rpm you will need a tomei solid lifter conversion kit, titanium retainer, dual valve springs(ferrea preferrably...still need to shim it for more seat pressure), lifter valves. this is a lot of parts but if you dont do it you cant rev high consistently and you will float valves.
 

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grease monkey
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1,386 Posts
i don't see a problem w/ revving it out some more, i say go for it and if you break something, well than you know what you need to upgrade. good luck, i say go for it. let that bitch scream.
 

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Registered
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953 Posts
if you have the regular sr20de/t crank it has a 86mm storke. if you do the numbers for it the max rpm you can safely run on it for prolonged periods of time is around 8700 rpm. after that point the piston speed become too high. you should not exceed 25m/s for piston speeds. if you get at sr16de crank it has a 62.7mm stroke(i think it close to that). when i did the math with the sr16ve crank you can rev 10200 rpm. formula 1 cars dont exceed 25m/s for piston speeds...neither should your engine. to safely run to 8700rpm you will need a tomei solid lifter conversion kit, titanium retainer, dual valve springs(ferrea preferrably...still need to shim it for more seat pressure), lifter valves. this is a lot of parts but if you dont do it you cant rev high consistently and you will float valves.
Wow, 10,200rpm sounds good :biggthump

Can't you use a little bit longer rods w/ the SR16 crank to keep the piston speeds lower? Or is it the other way around?

Anyway, using the SR16 crank would decrease your displacement (unless you use longer rods to keep a longer stroke) and thus the turbo that he has now will be come a bit on the big side, no?

Sorry if what I typed is completely wrong, I am not in a really good mood, and my head hurts from work... just want to lay down and take a nap... can't think clearly... bah....
 

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I drift Soarer
Joined
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259 Posts
if you use the sr16 crank and bore and sleeve it to 90mm it will be like 1830cc diplacement. thats is the most you can do with an sr motor. i dont think it is possible to go any bigger that a 90mm piston in our motor. it would be pretty nutty to rev it to 10200 but pointless on a turbo car. he wants torque and with the previously stated setup he wont have any power until he's more that half way down the track....and especially torque.
 

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CAR SLÜT
Joined
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1,622 Posts
Plenty of SR20VE's are rev'ving to 9000rpm though without major incident and the K20A's are into the 11,000rpm ranges with the same 86mm stroke. The main issue with F1 cars is the compression ratio and insane 19,000 RPM that causes the motors to last one race meeting(about 300 miles) even with black metal bearings.

Raising the rpm limit would be a good idea but I would consider dialing in the cams via the HKS cam gears to move the power band lower in the rev range. If your still running the stock 32 series gear ratios, it would prob be beneficial to keep the in gear torque output usable.
 
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