Why Boost? (1/4 Gain : Cost ratio)

[mikemjohnson]

Question: What is the average quarter mile time for a 5th gen h22 pushing a conservative number, lets say 7-9psi? the reason i ask is because i saw someone's 1/4 mile slip turboed (base model) running a 13.9. A base running stock is about 15. so spending near 3000 dollars gets you a mere one second gain? dont slam me for being 'blasephemous' or anything i am just curious how much a turbo helps you on the 1/4, and if the cost to time shaved ratio is better than other options

[91Si4WS]

1-2 seconds on a 1/4 mile time is a pretty big gain, you also have to wonder about run conditions it's obviously going to be harder to get traction boosted compared to stock..

[mikemjohnson]

yeah the very broad and general number ive heard is $900-1000 a second. its just that that time slip is one just a one second gain. is this just a bad driver or is this really all a turbo gets you?

[91Si4WS]

eh well a turbo can get you more or less, it really depends on the set up, which is where mainifold type, intercooler, turbo its self, boost controller, ecu, and mainly ecu tuning all comes into play, if a turbo setup isn't tuned right then it's not going to produce the numbers it should be compared to being profesionally dyno tuned. i think the fastest i've seen a prelude run on 9lbs of boost was a low 13, but thats still with it slipping on the start a little, and i dont think i've seen a compleatly stock 5th gen run a 15 flat or the 1/4, more around mid to high 15s depending on driver

[mikemjohnson]

so lets say hypothetically, i were to buy a turbonetics bolt on kit (http://turbokits.com/prelude_turbo_kits.html) what else would i need. would this be everything i needed, besides maybe a vtec controller to help it and a turbo controller for the interior.
btw, im not getting this anytime soon haha

[twokexlv6coupe]

i'm not nit-picking or anything, but stock 5th gen bases run 15.4's, not 15 flat so its more like 1.5 seconds.

but the more important thing is cutting a full second off your 1/4 mile isn't as easy as dropping in an intake and practicing your launching.
and considering the alternative (all motor) it would would prolly take at LEAST 5K to drop a second off your 1/4 (thats an absolute guess, it might be double that, but i havent really looked into N/A)

so cost for cost (and i'm pretty sure ogs will agree with me on this one) for the increase in power and speed, turbo > all motor.

[ogsmakdade]

real power isn't cheap. LOL I really shouldn't be allowed in here.

Oh and for the record I ran 15 flat bone stock. word.

[Mdtdnb]

3 g's for a turbo isnt that much money anyways when u add the fun factor the power gains.

[Rory]

I will give you one reason to go boost.. Once you have any kinda force induction. Everything you change in your car performance wise makes a bigger difference then N/A. for EX.

N/A + Exhaust = maybe a 15hp gain

Turbo + Exhaust = dawm near 40hp gain.

I went from a 2" exhaust to a 3" and it was a night and day difference. Its nuts.

[mikemjohnson]

just because i saw a twin turbo supra today, i was wondering, can you twin turbo a prelude? if so thatd be sick

[twokexlv6coupe]

you can, but its absolutely pointless. the fabrication time and work of making 2 manifolds, 2 downpipes, 2 dumptubes, etc etc etc. plus you'd hafta use 2 tiny tubos so they both fit in the engine bay, which would run outta breath up top..... its just pointless.

[Si Speed]

I ran 16.18 on a bone stock H23... came back with i/h/e and ran 15.35 in the same car. thats 8/10ths of a second. That was all about $350 so maybe I was an exception.

But yes, no matter what, if you wanna go fast, you gotta spend the money whether it's N/A, turbo, or just buying a faster car all together.

[twokexlv6coupe]

But yes, no matter what, if you wanna go fast, you gotta spend the money whether it's N/A, turbo, or just buying a faster car all together.


yuupppp. read teh bottom of my siggy

[94preludeguy]

I think turbo is a waste of money unless you are going to build the motor first. On turbo at 7-9 psi tuned good you will make about 70-90 whp. I have $2000 in my h22 with nitrous. I dont think there is a h22 with 9 psi that will run 11's 1/4. My h22 with 100 shot will. Here is a time slip from saturday on a 1000' track with my car on 100 shot. I am in the left lane car #7029.
http://i194.photobucket.com/albums/z273/94preludeguy/015.jpg

[ogsmakdade]

it an age old arguement that boils down to nothing more than personal preference. do what you like.

[Si Speed]

yuupppp. read teh bottom of my siggy

I couldn't agree more, but I shop around for bargains. :biggrin:

[twokexlv6coupe]

it an age old arguement that boils down to nothing more than personal preference. do what you like.

EXACTLY!!!!

[bc2_bb6]

13.9 for a boosted 5th gen doesn't sound too impressive. I ran 15.1 with a ebay CAI and junkyard tires with no wieght reductions. Temp wa sin the 90's if I recall.

It must be lack of experience as my first run with the same setup was like 16.4 and it kept getting better till I go the 15.1 by the 9th run. I'm sure I could of got to 14.7's with a little more practice.

I never got a chance to track the car when it was on the bottle, but at boost I have to expect low to mid 13's.

[deafy]

I'm shooting for high 12's on stock motor. I should be able to do it. It's all in the tuning and many other factors.

[mikemjohnson]

ive done a lot of research into since i first started this thread, and i think that i might want to save for a jackson racing supercharger. honestly, just for the low maintance and less maintance. a quick question, i have read on forums for other cars that you can, but can you use a blow off valve on a JRSC in a prelude? i know some JR kits with the eaton blower have internal works that dont require it, but id really want it just for the sound :D

[twokexlv6coupe]

you CAN add a BOV if you have a centrifugal supercharger, since they are extremely similar to turbos except they run off a belt from the engine instead of the exhaust gases.
this is a centrif SC
http://www.inamarillo.com/images/centrifugal-supercharger.jpg


but since the only SC option for 5th gens are a a traditional roots/eaton type SC, you cannot add a BOV to these.
http://www.aa1car.com/library/supercharger.jpg




reason being: with a centrifugal SC, there is extra pressurized air inbetween the SC and the engine (in the charge pipes) and when you lift off the throttle, the air has no where to go, hence needing a BOV.
since the roots type blowers are bolted to the block, there is no trapped pressurized air, so you can't use a BOV on these.

[preluderacer015]

there's a few factors that come into play, the main one being able to drive and not misshift. But also it depends on the turbo too and your setup depending on your setup tells you whether your getting your power at top-end, low-end or in between. Low-end you get good acceleration but will flatten out at higher RPMs, while top-end not horrible acceleration, but not as good as low-end power, but top-end is where you'll get the majority of your power from your turbocharger. In the quarter every component on the vehicle comes into play from the driver to the tires.

[mikemjohnson]

im about to invest in the basics first though, new K&N filter on my intake, some headers, downpipe-back ehaust with high flow straight through cat
(any input on those mods i just listed is appreciated: http://www.preludezone.com/showthread.php?p=85699)

[preluderacer015]

1-2 seconds on a 1/4 mile time is a pretty big gain, you also have to wonder about run conditions it's obviously going to be harder to get traction boosted compared to stock..

Like 91Si4WS said, a 1-2 sec reduction in the 1/4 is actually a really significant gain, even a 1/10 of a second is considered a good gain.

[95h22a1turbo]

mr. mike m johnson, I understand your very new at drag racing. To get 1-2 seconds in Drag racing is very hard or I could say little bit of cash and time consuming. Now if your stock car runs 15.xxxxxx from factory, and all the sudden you turbocharged it and ran 13.xxxxxxxx for 3k I think that is very impressive for being stock motor and turbo.
Just my .02

[R8GYY]

hell i would turbo my car just to listen to the dump valve sound all day..would it turn heads..hell yeah

[00CDMLUDER]

I will give you one reason to go boost.. Once you have any kinda force induction. Everything you change in your car performance wise makes a bigger difference then N/A. for EX.

N/A + Exhaust = maybe a 15hp gain

Turbo + Exhaust = dawm near 40hp gain.

I went from a 2" exhaust to a 3" and it was a night and day difference. Its nuts.


very true.

[Myles88]

ooooohhh ya, huge difference, just went from 2.5 to 3...sexy