2.2l stroker

[gpeele]

heh, has anyone noticed we all try to do the impossible? all my friends with v8's are trying to build high rpm drag cars. then, here we are splitting hairs about drivability at low rpms.

shoot, my sr will easily chirp the tires just transitioning from coast to half throttle in first at around 2k rpm. it falls flat from then till boost though.

too bad import stuff is expensive. i wish i could just point you in the direction of a good crate motor(reasonably priced) ans say, "that'll do ya".

hehe thats why i ditched hondas when i decided i wanted a true turbo car and not a rolling grenade.

[nismoconvert]

Does anyone know the rod lengths on the 2.2 Tomei stroker kit? I'm trying to figure out all the good stuff like r/s ratio, piston speeds, volumetric efficiency etc if I went with something like that later on.

[s13sr20chris]

nope, i dont have a clue. i will say the piston speed is prob high. the stock piston speed is not low for sure.

[RMiller]

That's just not something you do unless you have 10's of thousands of dollars to work with. Who cares what the piston speed is? You know that kit will rev high and make good power so you don't have to think about that kind of stuff.

[nismoconvert]

Hahaha. Who cares about piston speeds? Yeah who cares about outrunning the flame front. Theres a really good reason if anyone's building a motor they need to know this stuff. I guess rod lengths and r/s ratios are pointless too.

[s13sr20chris]

its a judgement call. how long at what speed for x reliability.

[cnichols]

heh, has anyone noticed we all try to do the impossible? all my friends with v8's are trying to build high rpm drag cars. then, here we are splitting hairs about drivability at low rpms.

V8s can be made to rev over 8000 pretty easily. With a 4.00" bore and only 3.00" stroke, a Ford 302 (5.0) is a very oversquare motor.

I've seen dyno charts of an N/A carb'd 306 (0.030" overbore) that was making 600+ hp at 8400 rpm. Can't argue w/ that.

[RMiller]

Hahaha. Who cares about piston speeds? Yeah who cares about outrunning the flame front. Theres a really good reason if anyone's building a motor they need to know this stuff. I guess rod lengths and r/s ratios are pointless too.

Give me a break. How high do people want to rev their motors? 10,000 rpm? Most people, even those making huge power rev to around 7500, which is fine with that stroker kit. How do I know it's fine? Comparison. Factory motors with longer strokes rev to a comparable speed. You go ahead and make those calculations, but I'm telling you the good folks at Tomei, Jun, whatever, already did them for you.

[s13sr20chris]

You go ahead and make those calculations, but I'm telling you the good folks at Tomei, Jun, whatever, already did them for you.

yeah, but what kind of life expectancy were they calculating for?

[RMiller]

yeah, but what kind of life expectancy were they calculating for?

Alright, I actually ran some calculations and guess what? A stroker kit with stroke of 92mm up from 86mm changes piston speeds to the following effects: Average piston speeds for the stroker kit at 7500 rpm are almost identical to stock stroke at 8000, with the stroker kit about 1/4% higher than stock. Compared to the KA revving to the stock redline of 7000, the stroker kit revving to 7500 has average piston speeds 2.5% higher. The factory KA redline is meant for longevity. And I think it's safe to say revving to 8,000 is not overdoing it with the stock SR stroke as far as busting rod bolts goes.

[s13sr20chris]

we are splitting hairs freind!

i will take your math and run with it because i dont feel like going back and doing it again. i will say i have seen one very well kept(and road raced) sr20ve wipe out the rod bearings with an 8000rpm redline. it took about a year and a half of daily driving with frequent autocross and road racing to do that. it was meticulously maintained with redline oil. on the other hand the ve does not have the main girdle. back to original hand, a main girdle should not really cause rod bearings to crap out.

hah, one sr does not a case study make. my sr only sees 7500rpm in first gear. all the others i just shift at 7000 because i have done the math and its not a significant gain in my state of tune.

hmmm, did we come to a conclusion? oh yeah, do what ever you want and some of us will agree while some others of us will tear it apart with our words and numbers.

[RMiller]

we are splitting hairs freind!

i will take your math and run with it because i dont feel like going back and doing it again. i will say i have seen one very well kept(and road raced) sr20ve wipe out the rod bearings with an 8000rpm redline. it took about a year and a half of daily driving with frequent autocross and road racing to do that. it was meticulously maintained with redline oil. on the other hand the ve does not have the main girdle. back to original hand, a main girdle should not really cause rod bearings to crap out.

hah, one sr does not a case study make. my sr only sees 7500rpm in first gear. all the others i just shift at 7000 because i have done the math and its not a significant gain in my state of tune.

hmmm, did we come to a conclusion? oh yeah, do what ever you want and some of us will agree while some others of us will tear it apart with our words and numbers.

Oh rod bearings. I thought you were worried about breaking rods, rodbolts, etc. but it doesnt matter because the kit replaces those stock parts with what I assume are more durable parts.

It doesn't surprise me that a frequently road raced car would die after a year and a half. And it's just the rod bearings. So you replace them, it's to be expected on cars that are raced often. Also, maybe the oil got too hot, who knows? Maybe different bearings would have held up when those ones didn't.

To sum up, if I wasn't sensible about spending money I would buy a stroker kit for the improved powerband and blingism. I think we would both agree that the stroker kit is better than stock for drivability.

[Nismo_Freak]

Alright, I actually ran some calculations and guess what? A stroker kit with stroke of 92mm up from 86mm changes piston speeds to the following effects: Average piston speeds for the stroker kit at 7500 rpm are almost identical to stock stroke at 8000, with the stroker kit about 1/4% higher than stock. Compared to the KA revving to the stock redline of 7000, the stroker kit revving to 7500 has average piston speeds 2.5% higher. The factory KA redline is meant for longevity. And I think it's safe to say revving to 8,000 is not overdoing it with the stock SR stroke as far as busting rod bolts goes.

Couple of issues with your math/logic.

1. Gram weight of the piston and rod make for a large difference in how high the engine will rev2. KA redline is more like 67003. The SR's issue is keeping it's valvetrain in one piece, not the bottom end.

That being said... properly built SR's can sustain 8500 RPM redlines as long as you can keep the valvetrain in one piece. Stroking it would easily knock off a solid 500 RPM off of that because it will increase not only piston speed but piston weight.

[s13sr20chris]

I think we would both agree that the stroker kit is better than stock for drivability.

yup, it makes me drool.

blingism, thats the ticket

[RMiller]

Couple of issues with your math/logic.

1. Gram weight of the piston and rod make for a large difference in how high the engine will rev2. KA redline is more like 67003. The SR's issue is keeping it's valvetrain in one piece, not the bottom end.

That being said... properly built SR's can sustain 8500 RPM redlines as long as you can keep the valvetrain in one piece. Stroking it would easily knock off a solid 500 RPM off of that because it will increase not only piston speed but piston weight.

1. I always thought many aftermarket pistons and rods were lighter than most stock pieces. Furthermore, a longer stroke would mean the piston and rod total length, from bottom of rod to top of piston, would be shorter, so there would be less material for the shorter combo. 2. Oops. I always thought it was 7k, maybe I never stopped to actually check. 3. Yup, weak link.

[Nismo_Freak]

1. I always thought many aftermarket pistons and rods were lighter than most stock pieces. Furthermore, a longer stroke would mean the piston and rod total length, from bottom of rod to top of piston, would be shorter, so there would be less material for the shorter combo. 2. Oops. I always thought it was 7k, maybe I never stopped to actually check. 3. Yup, weak link.

1. Larger bore = more material. The rod is the same length in the SR22, the piston is modified. My point was more in the fact that the KA has a different gram weight than the SR. Also within the SR you have the DE motor that revs a solid 500 RPM more than the DET in stock trim. That just so happens to be the same difference between KA and SR. My point is that piston speed AND piston weight are equally responsible for the RPM.

2. Werd

3. Werd

[RMiller]

I thought you were comparing SR stroker to SR stock. Didn't know you were comparing it to KA. I see....

For displacement I'd rather bore anyway. All bore 2.2 would cost way less than a stroker 2.2. And I understand the advantage stroke has in developing torque is almost nothing, contrary to the myth. A guy on I believe rx7club had dynos of 2 equal high displacement (like 427 or something)small block chevys, one all bore and the other stroked. They made simlar torque values.

p.s. mu(greek)=mv^2, so piston velocity should affect momentum more than mass. It doesn't seem like the two are equally responsible for stresses that limit revability.

[s13sr20chris]

Also within the SR you have the DE motor that revs a solid 500 RPM more than the DET in stock trim.

now heres a thought...is that due to bottom end differences or camshaft differences?i have heard that the det cams are more agressive(slightly) than the de. i will have to find out. i have an angle gauge and dial indicator that i have been meaning to put on my stock cams(after the valve job is done).

[Nismo_Freak]

now heres a thought...is that due to bottom end differences or camshaft differences?i have heard that the det cams are more agressive(slightly) than the de. i will have to find out. i have an angle gauge and dial indicator that i have been meaning to put on my stock cams(after the valve job is done).

There are at least four variations of the DE cams.

1. Early Cams (B13 motors) 2. Late Cams (B14 motors)3. Roller Cams (B15 motors) 4. VVT Cams (S14/15 motors)

So honestly it could be refering to anything.

The DE cams in my NX2000 are the "hot" cams found in the B13 engines.

Early Intake Cam (B13, Early G20, NX2000)

- 248 Duration - 0.394" Lift (10mm)- 111 deg. Centerline- 114 LSA

SR20DE FWD Exhaust Cam

- 240 Duration- 9.2mm Lift

Same specs as the turbo cam.

FWD intake camshafts should swap over... would be a cheap upgrade to net a solid 5-7whp on the big end with the early intake cam on a DET.

http://web.utk.edu/~cjohns32/camlist.htm

I plan to run C3's on my NX

[Onizuka]

I plan on slightly rasing displacement with bore and increasing compression ratio. Turbo motors on crack rock it hard. I want the down low and high end and this is the way to do it in my opinion

Good thing they have 93 and 94 octane at the pump a block from my house.

[s13sr20chris]

I plan on slightly rasing displacement with bore and increasing compression ratio. Turbo motors on crack rock it hard. I want the down low and high end and this is the way to do it in my opinion

Good thing they have 93 and 94 octane at the pump a block from my house.

stamped with my seal of approval.