Searching for your engine F/I vs. N/A
06-18-2005, 12:43 PM
#1
Searching for your engine F/I vs. N/A
I would like people to understand the 2 major differences between F/I and N/A........
I think people today mostly go turbo "SR20det" not only due to the fact that it is turbo for added power, but lets face it the JDM engine swap is pretty cheap.
On the other hand you have the USDM KA N/A. Great for build ups to produce major power, but extremely expensive.
Tuners need to make a decision Major HP, or have a well balanced engine and vehicle.
For longevity and well balanced I chose N/A.
Oil tempratures in N/A engines run cooler keeping smoother power bands and longer performance "longevity in grand touring".
F/I on the other hand can boost high amounts of HP, but the engine isn't as well balanced on High boosting and isn't very streetable past 300HP in a 240sx, although is preferably the engine of choice for 1/4 mile times.
Oil tempratures on Highly boosted F/I can reach engine oil temps above 160degress F. As far as HP and longevity is concerned this degrades the top peak performance of the engine. Therefore long term use in Grand Touring will degrade the performance of the oil sooner than later also. Oil is the life force of any engine and also determines the over all life span of the internals of the engine.
For a well balanced drift car personally I would chose an internally built high compression N/A over F/I. The car itself would have less weight to distribute at the front end.
The power band itself is much more controlled in an enviornment under higher stresses and weathered conditions. Plus tunning N/A is much more simplified than tunning F/I.
For people that are high boosting you need to remember that the 240sx "s13's in particullar" is a light weight vehicle when compared to Toyota Supra's 300z's, and skyline's. It doesn't take alot of power to get the drift and too much power in a light weight car will give less control at higher revs. Besides even a 250HP N/A will get up pretty fast in lower RPM's, than it takes for FI to achieve boosting at higher RPMs, especially when comparing a 2.4litre stroker , to a 2.0 litre high rev engine.
Of course there will be the day when I wan't an import drag monster, with high boost. But I love the simplified tuning of N/A and the comfort zone of power it has to deliver.
In NO way am I saying one engine is better than another I am simply stating that in developing a project vehicle, balance, power, and control are very important options to consider when building a performance vehicle.
I decided to write this thread because I see alot of noobs or new tuners come along and say "oH if it's boosted it's better" that my friends is just plain ignorant. Build a boosted over 300 HP 240sx, but I recomend that you use it for the strip only, more than likely an accident will occur in the first year, and don't ever think that you can be an infalible driver either, "thats like saying you and your car are superman".
I think people today mostly go turbo "SR20det" not only due to the fact that it is turbo for added power, but lets face it the JDM engine swap is pretty cheap.
On the other hand you have the USDM KA N/A. Great for build ups to produce major power, but extremely expensive.
Tuners need to make a decision Major HP, or have a well balanced engine and vehicle.
For longevity and well balanced I chose N/A.
Oil tempratures in N/A engines run cooler keeping smoother power bands and longer performance "longevity in grand touring".
F/I on the other hand can boost high amounts of HP, but the engine isn't as well balanced on High boosting and isn't very streetable past 300HP in a 240sx, although is preferably the engine of choice for 1/4 mile times.
Oil tempratures on Highly boosted F/I can reach engine oil temps above 160degress F. As far as HP and longevity is concerned this degrades the top peak performance of the engine. Therefore long term use in Grand Touring will degrade the performance of the oil sooner than later also. Oil is the life force of any engine and also determines the over all life span of the internals of the engine.
For a well balanced drift car personally I would chose an internally built high compression N/A over F/I. The car itself would have less weight to distribute at the front end.
The power band itself is much more controlled in an enviornment under higher stresses and weathered conditions. Plus tunning N/A is much more simplified than tunning F/I.
For people that are high boosting you need to remember that the 240sx "s13's in particullar" is a light weight vehicle when compared to Toyota Supra's 300z's, and skyline's. It doesn't take alot of power to get the drift and too much power in a light weight car will give less control at higher revs. Besides even a 250HP N/A will get up pretty fast in lower RPM's, than it takes for FI to achieve boosting at higher RPMs, especially when comparing a 2.4litre stroker , to a 2.0 litre high rev engine.
Of course there will be the day when I wan't an import drag monster, with high boost. But I love the simplified tuning of N/A and the comfort zone of power it has to deliver.
In NO way am I saying one engine is better than another I am simply stating that in developing a project vehicle, balance, power, and control are very important options to consider when building a performance vehicle.
I decided to write this thread because I see alot of noobs or new tuners come along and say "oH if it's boosted it's better" that my friends is just plain ignorant. Build a boosted over 300 HP 240sx, but I recomend that you use it for the strip only, more than likely an accident will occur in the first year, and don't ever think that you can be an infalible driver either, "thats like saying you and your car are superman".
06-18-2005, 03:31 PM
#3
To put it simply, every driver has a style and preference on the type of power put down, not ever discipline of Motorsports requires alot of power. Turbo applications are good for some disciplines and bad for other and the same goes for the N/A setup
06-18-2005, 04:04 PM
#4
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Join Date: Jan 2005
Location: BoostGetsYouLaid
Posts: 78
Well, to be honest, I cant think of one application that a good solid N/A high power motor wouldent be good for. Accept for my grandmother to take to church of corse : ) Or perhaps my uncle who drives a hybrid to save gas.
06-19-2005, 03:25 AM
#5
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Join Date: Sep 2004
Location: knoxville tn
Posts: 999
vinnie and i come from the same school i think... i believe in instant power at any rpm... and that power needs to be dependable at all times... i believe turbos have their place as well as na motors... it is up to each person to decide when and were that place is...
it is rather easy (dont get all knotted up over this statement) to make boosted power... turbo supercharged or nos... and yes you can make more of it with forced induction... and even do it at a smaller cost than you can with na power...
it is up to each person to decide where they drive their car and how it is driven... i trust na power for every day driving... and as vinnie said when i build a drag monster it will be boosted and juiced... i am not too worried about turning in the quarter mile...
i decided to go with na because of the challange it puts in front of me... people say 300 hp on a ka is not reachable... i believe it is and there might be even more power in the motor waiting to be opened up... it takes time and money to do this...
there is a project that is about to be getting started by a major import magazine and a shop in ca that is shooting for 400 hp out of a ka... i have contacted one of the people involved in the build and hope to get some insight into where they plan on getting their power from... im also sending the shop a crank and head to get worked over... they are not the cheapest out there but if the work is as good as what i have seen then i should be plenty happy with the outcome... i will get a link to them some time and edit this message so others might get involved in the project...
who knows what we can come up with in the future of these cars and the motor that came in them...
it is rather easy (dont get all knotted up over this statement) to make boosted power... turbo supercharged or nos... and yes you can make more of it with forced induction... and even do it at a smaller cost than you can with na power...
it is up to each person to decide where they drive their car and how it is driven... i trust na power for every day driving... and as vinnie said when i build a drag monster it will be boosted and juiced... i am not too worried about turning in the quarter mile...
i decided to go with na because of the challange it puts in front of me... people say 300 hp on a ka is not reachable... i believe it is and there might be even more power in the motor waiting to be opened up... it takes time and money to do this...
there is a project that is about to be getting started by a major import magazine and a shop in ca that is shooting for 400 hp out of a ka... i have contacted one of the people involved in the build and hope to get some insight into where they plan on getting their power from... im also sending the shop a crank and head to get worked over... they are not the cheapest out there but if the work is as good as what i have seen then i should be plenty happy with the outcome... i will get a link to them some time and edit this message so others might get involved in the project...
who knows what we can come up with in the future of these cars and the motor that came in them...
06-20-2005, 07:08 PM
#8
Well most of my purpose for writing this thread is so that people can take into effect the planning needed for swapping or a build up.
This is what I have calculated for sr20det/CA18det swapping with no boosting.
SR20det and CA18det (with engine/ transmission/ecu/harness) NO INTERCOOLERS or PIPING INCLUDED
S15 engine: $3800
S14 engine: $2399
S13 engine: $1199
S12/13 engine: $1100 "CA18DET"
It cost an average of $800 for these installs, or what ever your own time is worth for this install.
Intercooler $600 depending on the quality and who you buy from this is just an average some are cheaper and/or more expensive.
Down Pipe, and intercooler/intake piping
$300 and your time for install, some welding required on the down pipe.
So here is the Damage report on cost for stock OEM JDM install/engine/and some basic parts....
S15/sr $5500.00 avg.
S14/sr $4099.00 avg.
S13/sr $2899.00 avg.
S12/13/ca $2800.00 avg.
NOW HERE IS MY POINT........
For the s15 engine swap you get the biggest bang for your buck without boosting with almost 250CHP. Heres the problem, no matter if it is the s12 through s15 engine swap in order to boost above 12psi more than likely you will want to reconfigure the ecu this can cost you anywhere $500 on avg. Also calculate larger flow rate injectors if you want to make over 300CHP. The list goes on and on. I didn't even include the 3" exhaust needed for mild boosting......... Get my point........
Now here is what it will cost for a KA build up at $4800.00 for 250+CHP.
Forged internals at 11.1:1 CR $780 "entire Kit"........
SR20det 370cc injectors High resistance $300
reground or used cams for $300 or JWF for $700"rip off", or the PDM for under $500.00
Advanced timing gears for $300
ECU for $500 "enthalapy"
z32 fuel pump, and FPR $350
OBX header $170
exhaust $250
Cost of install with open work of porting and honing cost $1750, or your time for build and work.
Rough cost of about $4800..........
So I spend a little less than the s15/sr engine swap, and about the same cost of the s14/sr engine swap. So do the math there almost relatively the same in cost once you add up all the necessary things needed for turbo apps..........
This is what I have calculated for sr20det/CA18det swapping with no boosting.
SR20det and CA18det (with engine/ transmission/ecu/harness) NO INTERCOOLERS or PIPING INCLUDED
S15 engine: $3800
S14 engine: $2399
S13 engine: $1199
S12/13 engine: $1100 "CA18DET"
It cost an average of $800 for these installs, or what ever your own time is worth for this install.
Intercooler $600 depending on the quality and who you buy from this is just an average some are cheaper and/or more expensive.
Down Pipe, and intercooler/intake piping
$300 and your time for install, some welding required on the down pipe.
So here is the Damage report on cost for stock OEM JDM install/engine/and some basic parts....
S15/sr $5500.00 avg.
S14/sr $4099.00 avg.
S13/sr $2899.00 avg.
S12/13/ca $2800.00 avg.
NOW HERE IS MY POINT........
For the s15 engine swap you get the biggest bang for your buck without boosting with almost 250CHP. Heres the problem, no matter if it is the s12 through s15 engine swap in order to boost above 12psi more than likely you will want to reconfigure the ecu this can cost you anywhere $500 on avg. Also calculate larger flow rate injectors if you want to make over 300CHP. The list goes on and on. I didn't even include the 3" exhaust needed for mild boosting......... Get my point........
Now here is what it will cost for a KA build up at $4800.00 for 250+CHP.
Forged internals at 11.1:1 CR $780 "entire Kit"........
SR20det 370cc injectors High resistance $300
reground or used cams for $300 or JWF for $700"rip off", or the PDM for under $500.00
Advanced timing gears for $300
ECU for $500 "enthalapy"
z32 fuel pump, and FPR $350
OBX header $170
exhaust $250
Cost of install with open work of porting and honing cost $1750, or your time for build and work.
Rough cost of about $4800..........
So I spend a little less than the s15/sr engine swap, and about the same cost of the s14/sr engine swap. So do the math there almost relatively the same in cost once you add up all the necessary things needed for turbo apps..........
Last edited by BigVinnie; 06-20-2005 at 07:35 PM.
06-20-2005, 08:13 PM
#10
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Join Date: Feb 2002
Location: NY
Posts: 1,841
I'm VERY skeptical those mods will get you to 250 crank on a KA. I bet it'd be 20-30 less... Anyway I feel like commenting on the thread. I'm just curious where you guys get the idea of instant power from a N/A set up? A F/I set up will produce crap loads more low end torque for everyday drivability. I've been driving with my sr for so long, now that it's being swapped again, whenever I get in a N/A car it frustrates me to no end. I really miss the boost when passing on the highway or driving up a simple hill. It was only 250 at the crank too (cost me $4k), but it feels slow now that I'm used to it. When it's running again it should be 300 until I get used to that too. 
06-20-2005, 08:56 PM
#11
Originally posted by CowboyTurbo
Hey Vinnie, have you seen people with that n/a KA setup that you outlined? What are their typical whp figures?
Hey Vinnie, have you seen people with that n/a KA setup that you outlined? What are their typical whp figures?
Rebello racing was doing the work, I looked at a couple project KA's in 510's they were doing, they sourced and subbed out most of there work. But the dyno results they were pulling spoke for them selvs.....
KA build ups are nothing new to me, I've been R&Ding the KA for a few years now, looking to get my build together so I can get highlighted in a mag, with NO SPONSORSHIPS of course.
The highest WHP I have seen is 238 "streetlegal". Devious KA gave us a video in another thread of an 11second N/A KA, but it was injected with NOS, so it isn't all N/A.
That cost given on the N/A KA is that of my build, I'm just waiting for sometime to put together my build, I am a contractor so I build cars as a hobby, all I get are weekends.......
I work weekends also so very little time right now......
Last edited by BigVinnie; 06-21-2005 at 08:15 AM.
06-20-2005, 09:20 PM
#12
Originally posted by I'm with Stupid
I'm VERY skeptical those mods will get you to 250 crank on a KA. I bet it'd be 20-30 less... Anyway I feel like commenting on the thread. I'm just curious where you guys get the idea of instant power from a N/A set up? A F/I set up will produce crap loads more low end torque for everyday drivability. I've been driving with my sr for so long, now that it's being swapped again, whenever I get in a N/A car it frustrates me to no end. I really miss the boost when passing on the highway or driving up a simple hill. It was only 250 at the crank too (cost me $4k), but it feels slow now that I'm used to it. When it's running again it should be 300 until I get used to that too.
I'm VERY skeptical those mods will get you to 250 crank on a KA. I bet it'd be 20-30 less... Anyway I feel like commenting on the thread. I'm just curious where you guys get the idea of instant power from a N/A set up? A F/I set up will produce crap loads more low end torque for everyday drivability. I've been driving with my sr for so long, now that it's being swapped again, whenever I get in a N/A car it frustrates me to no end. I really miss the boost when passing on the highway or driving up a simple hill. It was only 250 at the crank too (cost me $4k), but it feels slow now that I'm used to it. When it's running again it should be 300 until I get used to that too.
Further advancement will be made in the cams as well.
With high lift cams and the 370cc injectors accomplishing 250CHP on 2.4 litre's is no problem........
You missed out on the major porting that will be done and the matching spec exhaust cam.
What we have been talking about with F/I is spooling times to achieve higher numbers in boosting. "Boosted HP doesn't magically appear, and it chokes the engine the first 1200RPM to produce enough heat to create power for spooling". Also the spool times required to make power through the biproduct of torque, and heat variables "thermal dynamics"...
It's very simple.......
If an F/I high rev has 250 CHP and an N/A stroker has 250CHP, which one will make it uphill first?
The stroker will because it reaches it's top peak power sooner, and will shift sooner............
Now lets say you take a 145CHP SR and slap a turbo on it "sr20det"..... Now you have F/I, but you are using the torque the biproduct "heat in the mani" of the 145CHP to now spool 250CHP. The early spool times are lag in the power band that will produce higher numbers in HP in the TOP END POWER BAND..... It will take longer for F/I to produce CHP than it will for N/A if at there top peak in the power band have the same HP.
Using N/A SR to modifying F/I may be a bad example because other modifications such as injection flow rate are needed also...
Last edited by BigVinnie; 06-21-2005 at 08:25 AM.
06-21-2005, 10:50 AM
#13
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Join Date: Jan 2005
Location: BoostGetsYouLaid
Posts: 78
Originally posted by I'm with Stupid
I'm VERY skeptical those mods will get you to 250 crank on a KA. I bet it'd be 20-30 less... Anyway I feel like commenting on the thread. I'm just curious where you guys get the idea of instant power from a N/A set up? A F/I set up will produce crap loads more low end torque for everyday drivability. I've been driving with my sr for so long, now that it's being swapped again, whenever I get in a N/A car it frustrates me to no end. I really miss the boost when passing on the highway or driving up a simple hill. It was only 250 at the crank too (cost me $4k), but it feels slow now that I'm used to it. When it's running again it should be 300 until I get used to that too.
I'm VERY skeptical those mods will get you to 250 crank on a KA. I bet it'd be 20-30 less... Anyway I feel like commenting on the thread. I'm just curious where you guys get the idea of instant power from a N/A set up? A F/I set up will produce crap loads more low end torque for everyday drivability. I've been driving with my sr for so long, now that it's being swapped again, whenever I get in a N/A car it frustrates me to no end. I really miss the boost when passing on the highway or driving up a simple hill. It was only 250 at the crank too (cost me $4k), but it feels slow now that I'm used to it. When it's running again it should be 300 until I get used to that too.
You seem to be a bit confused on what instant power and low end power means. F/I setups dont have instant power or low end. Instant power is when you hit the gas, you dont have to wait for a turbo to spool up. When you have a high compression, high hp N/A beast, the power is always there on tap, its a matter of hitting the pedal and going fast, not waiting on a turbo.
Low end power is power in the low rpm's. Turbos dont have that, they actually have less in the low rpm's because thats when its trying to get the turbo started. It takes exhaust flow to spin the turbine, so the air doesnt flow as good as it should, thus you get less power at the low rpm, but once it does kick in, you get alot more power in the high rpm. Which is the boost kicking in.
Hope that helps explain a bit better.
06-21-2005, 04:56 PM
#15
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Join Date: Jan 2005
Location: SouthCarolina
Posts: 191
This has been discused many times before. Vinnie I agree with you, but it seems a turbo is the "in thing" now.(cough F&F cough) I myself am a turbo fan, but because I have always been a fan of a high revving engines, (not that a few simple mods cant make a NA KA a high reving beast) and I love the feeling of boost. I personally am planning on an RB20 swap, it's just more suitable for ME. This pretty much comes down to a question like that of what rims to buy. As with most EVERYTHING it really comes down to preference and usage.
I just don't want to see yet another thread turn into a post ***** catfight. lol
Why not open a thread with a poll? just for curiousity...
I just don't want to see yet another thread turn into a post ***** catfight. lol
Why not open a thread with a poll? just for curiousity...
Last edited by ZenkiOwns; 06-21-2005 at 04:58 PM.