Jesuscookies

iTrader: (1)

I am installing an HKS twinpower on my car.

Current set up is a single turbo, putting down about 400RWHP to the rear wheels.

Currently running nice with a well tuned PFC.

My question is, do I have to have the car retuned when I install the twinpower ?

Is there any danger in not retuning ?

Or, am I just a paranoid *** ?


Thanks as always for the help

xbootyguyx

Im sure your vary rich now a little more spark will just clean it up for you.

sillbeer

Just to be safe I would put it on a dyno and have it checked. There's no telling exactly how your car will react to the change. Could run a little lean.

This is just an opinion and I wouldn't go off of something as general as this. It's your car and since your single you put alot of money into it. It could be a costly mistake not having it rechecked.

-Destin

Jesuscookies

iTrader: (1)

Destin,

Thanks for the advice. I would not go off of just an opinion, as given in the above post. After you have been here for a while you learn how to sift thru the B.S. to get to the facts.

I guess another way to ask this question is, will I get more than 5RWHP as a result of this mod?

Thanks

jspecracer7

I think you'll find that your HP increase is one or two HP throughout the powerband. It may peak at 5 rwhp though. I would leave it alone.

particleeffect

i don't see how it can possibly make you run lean in the combustion chamber. it can help you burn your fuel more thoroughly(sp?) though so you would appear to have leaned up a bit, but the a/fr would still be the exact same.

but it can't hurt to hook up a wideband and have a look.

rx7raca

if im thinking correctly the hks TP is not made to be like a ricer puttin a can on his civic, making those extra 3hp, this system is made to smooth out the rpms when having large numbers of whp.

ive heard of people with around 450 putting the TP on and they say its a completely different feeling going through the rpms. "its sooo smooth"

its just to help out the coils(bigger boom) for those big hp motors.

if you plan to get anything over 425whp, i would consider it.

this is just my opion. i would look around, ive seen some threads about this, good luck.

edit:
i forgot you already bought this, and to answer your question, i would take it to the dyno to get a good idea of how different the a/f is. let us know what you find out.

rzograbian

hey david, where are you going to get tuned if you need to ?

rfreeman27

iTrader: (5)

And the stock IGN. system cant handle highboost levels.

fastcarfreak

My car made almost 15rwhp off of just installing the hks twin power. Great investment. I would put it on the dyno to see how it reacts. You may want it tuned in for safety purposes.

Jesuscookies

iTrader: (1)

What mods were you running?

fastcarfreak

mods are in sig, sorry

SleepR1

Before HKS Twin Power with 14.5 psi boost: 341.1 rwhp @ 6500 rpm; 281.1 lb.ft @ 5750 rpm. Had high-rpm miss (commonly known as ignition break-up).

After HKS Twin Power with 16 psi boost: 370.9 rwhp @ 7000 rpm; 304.7 lb.ft @5750 rpm. No more high-rpm miss. Rx7 Store's Jason Baughman made some minor adjustments to the air-fuel ratio.

The boost setting was the same for both runs, 1.05 kg/cm^2, 70% pr/sc base duty cycles for precontrol/wastegate.

Mods are plenty, and are the usual needed to make those numbers (FMIC/Intake/Koyo/Power FC/Fuel system upgrades, etc.).

I got my HKS Twin Power from MVP Motorsports. The amp is $439. Harness is $33. Shipping is $21 from TX to IN. Total $493. Worth every penny IMHO.

http://www.mvpmotorsports.com/Templa...176&SearchYN=N

Talk to Frank.

CCarlisi

I'm a little confused. Your boost settings were the same for both runs, but your actual boost was 14.5 on the first and 16 on the second? In any event that's a lot of power and torque. Enjoy =)

DrPJM1

The twinpower eliminated all of my ignition breakup, as commented previously by SleepR1. Car felt a lot better and smoother overall but did not require retuning. It was a very wothwhile modification and I was very pleased.

SleepR1

The runs weren't done on the same day. Run 1 was done on 3 Jan 04. We had just bumped the boost setting up from 0.90 to 1.05 kg/cm^2. The Power FC is a bit conservative while "learning" so we didn't quite hit 15 psi (shy by 0.5 psi). Run 2 was done yesterday (6 Mar 04). The Power FC had been left @ 1.05 kg/cm^2 and "learned" for three months. We made a change with the HKS Twin Power, and the PFC overshot the boost by 1 psi (set to 15 psi) during our test. After a few runs on the road, the Power FC got within 0.5 psi over the target (15 psi).

Also I had a mix of race and pump gas in the tank during the 3 Jan 04 run. The net octane rating then was 102. Jason added a bit more fuel at yesterday's tuning session to compensate for a full tank of 93 octane this time around. AFRs read 11.6 with pump gas, but during tuning with 102 gas, AFRs were 10.9; there was a 0.7 AFR point difference with a 9-point increase in octane--IOW--if your car is tuned with 102 race gas, when you put 93 pump gas in the tank, your AFR will lean out by 0.7 points (at least that's what we found out yesterday).

Point is, we don't think the HKS Twin Power could lean out the AFRs by 0.7 points--we attribute the AFR leanness to the lower octane pump gas during yesterday's tuning session--so for me, the tuning session was for adjusting the AFRs for pump gas, not necessarily for compensating for the addition of the Twin Power ignition.

At a lower boost setting numbers were still decent:

Before HKS Twin Power (3 Jan 04): 320 rwhp @6500 rpm, @13 psi
After HKS Twin Power (6 Mar 04): 340 rwhp @7000 rpm, @ 13 psi

3 Jan 04 run (before HKS Twin Power), Power FC was set to 0.90 kg/cm^2 (~13 psi). Boost target was right-on.

6 Mar 04 run (after HKS Twin Power), Power FC was set to 0.85 kg/cm^2 (12 psi). Power FC boost control overshot by 1 psi. After a few runs on the road, the Power FC was within 0.5 psi over the target (12 psi).

I can't explain why the boost was higher with the HKS Twin Power? Point is the HKS Twin Power ignition amp made a positive difference. If you want to realize your motor's full modified power potential, the $500 HKS Twin Power is a worthwhile investment.

Other interesting data points during the Rx7 Store tuning session yesterday (6 Mar 04):

Water Temp: 84 C (183 F)
AIT: 35 C (95 F)
AFR @ 16 psi WOT, 93 unleaded pump gas: 10.9 to 11.1

Note that AITs were a bit on the warm side during tuning (from heat soak). Once on the road, with ambient temp @ 50-ish F, the AITs dropped to 22 C (72 F), so the car felt even stronger @ WOT 15 psi boost setting...probably closer to 380 rwhp...scary-fast

(Here's my handy resource for unit conversions. Bookmark it! http://www.onlineconversion.com/temperature.htm)

Fish

Well I had better get my twin power installed then.

Dan

SleepR1

Yeah, you should. Install the Twin Power box right over the igniter. You'll need a slightly longer screw (8-mm hexhead), and 7 small washers. If you got the HKS Twin Power wiring harness, installation is a breeze. You might need to remove the intake elbow to get to the ignition harness, which is tie-wrapped to the power steering hose.