Bolt On Si -- no tuning vs tuning comparison

Think about the MPG increase as well though, a good tune for bolt ons will leave you with much better gas mileage than stock. Especially because if you just bolt on and go, the ECU will run rich to compensate and you will get worse mileage than stock with no tuning
 
Well, I guess this is my question...

tune on a bone stock Si can yield up to 21hp. Tune on a modded Si, which makes no more (or even less) power than a stock one, yields something like 17hp? So really you're better off with a tune only than a tune and full bolt ons?
 
Final thought -- looks like the K&N Intake is actually worse than the OEM airbox and kills top end post 6000 rpm -- I have had 9th gens make better top end with the stock intake, which was only beat by the PRL CAI so far.


If you read all of it Vit says that the stock airbox is better than all the intakes except the PRL. All the rest seemed to hurt the numbers. Full bolt ons including new intake manifold, throttle body, and the DP/exhaust will net you pretty good gains. Just a filter on a stick intake won't do much. But yes, it does look like stock with a tune is a pretty good way to go. I think axion industries has their car in the 250hp range with "full" bolt ons so it just depends on the parts you get.
 
carpenj said:
Well, I guess this is my question...

tune on a bone stock Si can yield up to 21hp. Tune on a modded Si, which makes no more (or even less) power than a stock one, yields something like 17hp? So really you're better off with a tune only than a tune and full bolt ons?
Click to expand...
You can hit 230's-240's wheel horsepower with bolt on mods. That's without cams.

Intake
Exhaust
Downpipe
Rbc intake manifold
Zdx throttle body
Flashpro/tune
/230-240's to the wheels
 
Thanks Webby and Nix...now that's more like the numbers I was hoping to see! I will probably never take my mods that far, but maybe a PRL intake on the stock manifold and a downpipe with a tune would be more like my planned route.
 
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It gets very expensive to try and get 300+ NA..... That's where the SC/Turbo route takes over. Not that its impossible...... What are your goals man?
 
My beginning performance goal for this car is to be in the 14.2 range in the 1/4. After that, maybe sway bar and once the car has several years on it, who knows lol.
 
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Tires first then! Some great performance tires will make the most difference. Also lots and lots of practice. Other than that some parts can just improve the overall driving feel of the car. Ex: a tune, fixes rev hang & just makes it run as well as possible, and a larger rear sway.

I bet with full bolt ons, meaning IM, TB, & so on, you would hit pretty good numbers to the wheels with a good tune.
 
webby said:
You can hit 230's-240's wheel horsepower with bolt on mods. That's without cams.

Intake
Exhaust
Downpipe
Rbc intake manifold
Zdx throttle body
Flashpro/tune
/230-240's to the wheels
Click to expand...


I like what I'm reading here...no force induction planned. Everything you listed there would probably be the most I'd ever do to my car.

My plan is to get exhaust/Downpipe first, If I got flashpro, is it worth getting a tune for those 2 items?...or should I just reflash/flash with one of the base maps provided...and just hold off till I get all the bolt on's I want?

Also for those of you that have tuned/reflashed with flashpro...does it mess up any of the "I-MID" screen?...do I lose any "functions" or does anything go wonky?

Apologies if I'm beating a dead horse here and if its been mentioned in another post....I've just recently started being more active on this forum, because I'm just starting to finally start to Mod my baby after a couple years :)

Cheers & Thanks!
 
VitViper said:
Thanks webby.
The PRL CAI is the only intake I have seen to date that actually makes any power over the stock airbox. All the typical 'rush to market' intakes I've seen so far make doo-doo power.
Click to expand...
I have a K&N SRI on my 2012 Si but I just traded that car in so I'm taking it off. (probably gonna sell it)
I was thinking of the PRL CAI for my 2014 Si and now I'm definitely going to go that route.
@VitViper you wouldn't happen to know if the Hondata works on the 2014's yet or is it too early? :confuzzled:
 
These engines do not come close to making a true 230 whp. If they did you'd see 103-104 mph trap speeds. And i haven't seen one do that yet.

i've seen 101-102. I'd guess those cars make around 210 whp.

I mean the guy that is making 240 whp on 7 psi trapped 105, so for reference you'd be looking at the trap speeds i mentioned here. As it is now, i rarely see the 13+ si's going faster than 98-100 mph. This tells, me they're around 195 whp.
 
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w00t692 said:
These engines do not come close to making a true 230 whp. If they did you'd see 103-104 mph trap speeds. And i haven't seen one do that yet.

i've seen 101-102. I'd guess those cars make around 210 whp.

I mean the guy that is making 240 whp on 7 psi trapped 105, so for reference you'd be looking at the trap speeds i mentioned here. As it is now, i rarely see the 13+ si's going faster than 98-100 mph. This tells, me they're around 195 whp.
Click to expand...

Care to elaborate on the direct correlation of horsepower to speed?
 
Tire pressure/specs, track prep, weather, wind direction/speed, driver...so many factors contribute to trap speeds. I see where you're coming from since we used to bench race and set up runs based off of trap speeds between cars but to say such a specific whp number idk.
 
Ok so what ive read is that the rbc intake manifold is crap, all intakes other than prl is crap. And the rbc was required to get in the 220+ hp range. Without either of those we pretty much cant break 200 hp. So my question is is it just not worth it to do anything on our cars outside of forced induction?
 
Bulkybear said:
Ok so what ive read is that the rbc intake manifold is crap, all intakes other than prl is crap. And the rbc was required to get in the 220+ hp range. Without either of those we pretty much cant break 200 hp. So my question is is it just not worth it to do anything on our cars outside of forced induction?
Click to expand...
:yeahthat:
 
The difference between 175 whp stock and 200 whp after mods is large. There are some areas where you'll gain 20-30 ft/lbs of torque over stock with a downpipe and intake.

All in all, you should be happy it responds that well with only 2 modifications lol.
 
Nah. Im less inclined to buy anything for my car other than forced induction if I can't even break 200 whp. I was actually considering staying NA and aiming for 230 whp. But since we have discovered the rbc is no good and that was required for that hp I may as well just save the money.
 
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