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GTR Dreamer
07-04-2004, 12:00 AM
hi guys,
i hope that in the future i will buy a S15 200SX and i want to modify it to get some more power, maybe 350hp+,
ive heard of this happening but i was just wondering wot the best things to do to it are. here are some options that ive considered.

1.ive heard of acid dipping the block to make it stronger but would that be worth it (how strong is the SR20DET or would there be a different method of strengthining it).

2.wot about some aftermarket forged pistons?

3.is it worth doing anything to the conrods and crankshaft?

4.the head. maybe aftermarket cams and gears, what about the valves or port and polish.

5.fuel delivery/air intake. upgrade the pumps and injectors, maybe a fifth injector by the plenum?, it seams as though a quad throtle setup would be more responsive, is this true. a turbo upgrade with intercooler ect.

6.ECU upgrade/remap maybe?

7.exhaust header and strait through 3inch pipe with limited restiction muffler.

8.does the cooling system need anything done to it, or is it okay stock?

9.ignition upgrade?

10.wot about a twinplate clutch, or upgrade

11.RB25 gearbox, ive heard the S15 six speeder is weaker under preasure.

12.is the stock diff okay? ive heard that a helical LSD is your best bet.

i know itll cost a bit but i think itll pay off in the future.
wot do u think.

:D :D :D :D :D :D

TheOne
07-04-2004, 01:23 AM
the block is strong enough for probably 400-500 to a maybe 600(that would be pushing it) i've seen a lot of sr20det's makin more than 400 at around 15-17 PSI

well, some custom JE forged pistons with a 9:1 compression ratio, some crower connecting rods, the stock crankshaft will probably resist 400hp.
for the head you can do port & polish, aftermarket cams(comp cams is a good company) and forged valves.
for fuel/air i think greddy makes an intake manifold for the sr20 which is quite smaller and better than the stock, also some 550cc injectors, a garrett t3-t4 or HKS turbo with front mount intercooler(stock sr20 intercooler is side mounted).
for the ecu the engine management system, as a remap is necessary for some of the upgrades.
usually some companies make custom exhausts for such and such turbos so that'd be best way to go, free flow exhaust.
for coolin, yes it needs to be upgraded to handle all the power, koyo makes a good 3 core radiator for sr20's, and dual fans should do that.
the engine management system takes care of the ignition with the coil packs

that should make you a good 350hp or 450hp, you can also put 740cc injectors and more psi and it'll do more, + a good dyno tune so everything goes fine. thats gonna cost a lot by the way, this is all expensive, those forged connecting rods run around $5-700(all 4), the pistons and a greddy turbo kit with better turbo costs like $4000USD.

GTR Dreamer
07-04-2004, 01:24 AM
okay, so before you all say 'whats it going to be used for' or 'how can we comment if we dont know the intention for the build', ill tell ya.
it will be a street car with the odd bit of drag racing or track racing, and some motorway/highway bursts/driving.

GTR Dreamer
07-04-2004, 01:29 AM
gee thanks 'TheOne' thats heaps of great info. thanks heaps!!!!!
:D :D :D :D :D :D :D :D :D

Egg Nog
07-04-2004, 04:44 AM
There's also another interesting alternative method of strengthening parts... cryogenics is beginning to establish more respect and is becoming quite a well-proven technology. It is especially noticed in race engine rebuilds, when comparing an engine with cryogenically-treated parts to one without. It might be a little expensive, but it seems to be a pretty cool idea... You can treat tons of parts too - brake rotors, cranks, turbochargers, entire engine blocks, etc.

It's an awesome technology. Very promising. Many companies have even seen power and torque gains when entire engines have been treated. See the attached graph (for a small 2-stroke kart engine).


A few good links:

http://www.300below.com/site/processors.html
http://www.onecryo.com/motorsp.htm
http://www.300below.com/site/motorsports.html
http://www.cryopro.com/engine.htm
http://www.motorsportsengineering.sae.org/motorsports/community/havener-cryogenic.htm
http://www.by-the-sword.com/new/cryogenic_tempering.htm

GTR Dreamer
07-04-2004, 02:21 PM
okay, thanks guys, just a few more things to clarify.
is there any need of an aftermarket head gasket?
what about the oil system?
are the rocker arms ok stock?

once again thanks heaps

:D :D :D :D

TheOne
07-04-2004, 03:38 PM
the sr20det doesn't use rocker arms:) thats for pushrod engines, not dohc engines.
you do need an aftermarket head gasket for better durability and compression, some companies sell metal head gaskets.
you need an oil cooler with that much power, oil pump, and good synthetic oil(mobil 1 is a good 1), or royal purple(racing oil).
i can't tell you much about the drivetrain as i haven't researched much on that side, i've done my research in engines since i own an s13.

johnnynumfiv
07-04-2004, 04:24 PM
another thing to get comphresion down is to mill the bottom of the head down, so the head is lower on the block.

GTR Dreamer
07-04-2004, 06:01 PM
the sr20det doesn't use rocker arms:) thats for pushrod engines, not dohc engines.
ok im confused, i posted the same topic on another forum (nissanforums.com) too get as much info as poss, one of the replies contained this,

"Nismo sells a set of retainers for the rocker arms to keep them in place at high revs, that takes care of that problem."

and on how stuff works in the camshaft section it had rocker arms in the diagram. Whos wrong? :confused:

what do u think is going on? :confused: :confused: :confused:

Egg Nog
07-04-2004, 06:17 PM
The sr20det does use rocker arms... for each of them, one end is attached to the valve stem, and the other is attached to the camshaft lobe. It's not really too uncommon on OHC engines...

GTR Dreamer
07-04-2004, 07:01 PM
yay!!! :D not confused any more.
so if it diddnt have a rocker arm, would the lobes just push the valve?
:cool: :)

Egg Nog
07-04-2004, 07:07 PM
yay!!! :D not confused any more.
so if it diddnt have a rocker arm, would the lobes just push the valve?
:cool: :)

I think you've basically got the hang of it now :)

GTR Dreamer
07-04-2004, 07:23 PM
the pistons and a greddy turbo kit with better turbo costs like $4000USD.
is that pistons and a turbo kit together. whats in the turbo kit? :)

TheOne
07-04-2004, 07:41 PM
nah, thats the turbo kit only, the pistons do cost though. greddy sells a turbo kit which comes with the turbo, exhaust manifold, intake pipes, intercooler, fuel injectors, and everything else needed.

GTR Dreamer
07-04-2004, 11:21 PM
so what size do u think is the best turbo 4 around 16-20 psi of boost. sounds like GReddy is a good brand right?
when you do the fuel system do you need a pump upgrade aswell?
:) :) :cool:

GTR Dreamer
07-05-2004, 06:57 PM
are the stock suspension/brakes ok?

TheOne
07-05-2004, 07:07 PM
HKS, GReddy, turbotenics. i've looked around and seen a garrett T3/T4 turbo can handle 16-20 PSI tho am not so sure, you do have to upgrade the fuel pump and injectors, as the stock wouldn't handle so much PSI, seen sr20's with 550cc or 740cc make 400hp, and a 255lph(however ya spell) walbro fuel pump.

for safety reasons yes, an upgrade to the suspension and brakes would help, it'll make ya stop faster than the stock brakes, and some suspensions even help with the traction.

GTR Dreamer
07-05-2004, 09:21 PM
thanks.
i was just looking at a local NZ magazine and one of the colums is called 'speed clinic' this is where readers write in asking technical auto questions. any way one guy asked about fuel pressure regulators, the reply was quite interesting. sounds as though u wouldnt need to go to bigger injectors for more response, just turn it up 10psi or so and ur away. what do you think about this on a SR20DET?

Ferrari Tifosi
07-06-2004, 12:33 AM
yay!!! :D not confused any more.
so if it diddnt have a rocker arm, would the lobes just push the valve?
:cool: :)

The camshaft lobe hits the bottom of one side rocker arm which in turn makes the other side of the rocker push down and open the valve.

GTR Dreamer
07-06-2004, 01:32 AM
The camshaft lobe hits the bottom of one side rocker arm which in turn makes the other side of the rocker push down and open the valve.

yea, i learnt that, all thanks 2 Howstuffworks.com, great site that :D

Ferrari Tifosi
07-06-2004, 10:54 AM
yea, i learnt that, all thanks 2 Howstuffworks.com, great site that :D

Ahhhh, great site, lots to learn from it.

GTR Dreamer
07-09-2004, 03:33 PM
i have now found out how much some pistons will cost, these are off the shelf with a bore of 3.386 but custom ones cost even more, do you think the off the shelf pistons would be ok? they cost $3200NZD

also i have found out how much 4 crower conrods is, but there are 2 ways i can go
a. steel billet rods, @ $1060NZD for 4
b. titainum rods, @ $2200NZD for 4

what do you think will be best steel or titainium?

or i can get a GReddy stroker kit for about $5000NZD i dont think this will be as good as crower or JE though, am i right?

:cool: :cool:

Egg Nog
07-09-2004, 04:18 PM
I looked at the conversion rates (NZD to CAD), and still, it seems that those prices are pretty ridiculous. Are you really considering paying a large part of what the car is worth for a few small parts? From what I've heard, the SR20DET is a fairly strong engine...

I think the best option would be the most cost-effective route... find a local tuning shop, and ask them about the most reliable and cost-effective way to get more power. Especially try to stay away from GReddy parts, though. They may be decent, but you can easily find equivalent parts for waaaayyy less money. GReddy marks up their prices just because they've become an established name brand.

demon
10-03-2004, 07:30 AM
If your looking for some serious help with the SR20DET let me know, I have a Datsun 510 with a T3/4 Turbonetics Turbo with MSD Injectors (Yes Top Mounted) pushing 20psi @ 503 WHP. I did all the work myself (except machine work) and you can easily get 500 HP for 3,000.00 USD. I wouldnt recomend much past 600HP unless you have your block modifed. If you want more than that go with a RB26DETT.

Email me with any questions you might have.

redrum
03-30-2006, 03:24 PM
hi guys i what to know whay can i do to get 400+hp out of a stock sr20 silvia

h00t_h00t
03-30-2006, 04:14 PM
Read the first page?

Was GTR's 200sx ever built?