NA build pointers

[jeffske]

sell b18c and wack in k20 ..

wouldnt that require an engineer cert?

[ALLMTR]

It is hard for me to quote prices as I've been lucky enough to never pay retail. (BIG thanx to you Dave) My "kit" was about 65 bucks I think.

I was waiting for everyone to say, "No way will that combo run low 12's" but with NA the car is MUCH more important than the motor

[ALLMTR]

wouldnt that require an engineer cert?

That would be about the easiest/cheapest part of the conversion

[tinkerbell]

wouldnt that require an engineer cert?

so would a B20...

[BlitZ]

wouldnt that require an engineer cert?

and so does the aftermarket gearknob.. b18c should also need one as they didnt come in doch vtec.. and was it 1.6 std? im not sure

[mocchi]

NA Build Pointers:

1. Think your fuel supply, octane rating which you will use. (91, 95, 98, 100+)
Can you afford the fancy fuel to keep it up

2. Then your Compression rate.

3. Then how high do you want to rev it up.

In NA cars power comes from head, so its vital to maximize your head by:

- Improve swirl effect to compress more air in cylinder
(we would want max Volumetric efficiency)
- Lighter valve train weight (Lighter valve, springs, retainers)
- Intake and Exhaust modification to improve breathing efficiency.

Note on Exhaust mod:

-Long pipes lift low rpm power while short pipe lift top end.
-Pipe diameter fixes peak horsepower rpm.
-Tuned stepped headers (headers with diff. pipe diameters) & unequal length
pipes will improve overall hp & torque.
-To improve mid-range hp, the header tube roof can be lowered to line up with exhaust port, making the header tube floor lower by say.. 0.125in max from exhaust port.

Piston:
-Make sure your piston is smoothed out, no rough edge to improve flame travel.
-Maximize squish area on piston (if you can avoid high-top piston as it reduces flame travel)
-Match piston squish area and combustion chamber squish area

Bottom Block:
If thinking of reving it up high, strong high quality bolts(rod, head etc) is crucial. the con-rod is where highest pressure and stress accumulates (goes up and down continuously)

Building NA engines are hard. Lots of modifications will only add like 1-2% of max hp but if you want to suck every last drop of power... its all yours.

___bib.
squish: also called quench area, quench band. It increases the surface area of combustion area and actually cools or quenches the burning mixture around the edges of the combustion chamber. This assists in maintaining a steady (not violent) burn rate and offsets any tendency for high speed detonation or pre-ignition to occur.

detonation and pre-ignition are different.

detonation: a violent burning of fuel, almost like an explosion caused by the colliding flame fronts after the spark plug has fired. a piston damage by detonation will show signs of pitting on the crown (cracks and depressed area around it)

pre-ignition: self ignition of fuel caused by a hot spot within combustion chamber. symptoms on piston: if a hole is present on piston crown, it will have melted appearance.

Information were derived from a book called 'Four-Stroke Performance Tuning' by A. Graham Bell, 3rd edition.
Continued..

[ZeForce]

...It increases the surface area of combustion area...

You might want double check that statement, usually the aim is to minimise the surface area of the combustion chamber, ideally a spherical shape, to reduce the time it takes for the mixture to burn.

Optimising quench area and maximising combustion efficiency is one of the most crucial parts of building a good naturally aspirated engine, or any engine for that matter....

[mocchi]

well the book actually says increase, not decrease.

i will be trusting the book unless you have the knowledge or experience like the author does.

do you?

[tinkerbell]

sounds like a trade-off in terms of: detonation risk versus combustion efficency.

so you guys had better be talking "apples to apples" or you are wasting your typing time...

[ZeForce]

sounds like a trade-off in terms of: detonation risk versus combustion efficency.

so you guys had better be talking "apples to apples" or you are wasting your typing time...

There is no trade off, increasing combustion efficiency will prevent detonation

[SHW.70Y]

im absolutely loving this thread, its helping me out heaps in my build progress although i dont own a honda lol.
good luck with whatever you choose to do hope it works out for the best

[Illegal]

Who says a drag car needs to run 10's?

A consistent 13 second car can easily do well in dial your own bracket racing.

my stock jdm type-r 98 motor on hondata s100 and slicks in a eg hatch ran a 13.04