DamonB

Just put on an M2 dual tip and now I am getting 15 psi spikes in second gear. Only other mod is a downpipe. My boost pattern is 11-9-15-11. Before the catback it was 11-9-12 (on cold days)-11. This spike worries me as the car is run hard often at the autox. Can I bring this spike under control by just adjusting pill size in the prespool? This is my only option as any boost control, wastegate porting etc is illegal in my racing class.

GoodfellaFD3S

iTrader: (213)

Heres what I know,
Keep the cat-back and down-pipe and sell the rest of your car. Take what you have left and weld it on to a 1988-89 Dodge Aries K car and hold on for the fun ride of your life...BITCH...BOOOYAH

atihun

You will need to control that boost one way or another.

I don't see an upgraded ECU, so I am assuming that you are still using the stock ECU.

In that case you are in danger of grenading your engine if you keed driving it like it was stolen

Yes, you can change the stock pill size. You will put in a larger pill to reduce the overall psi. For some people though, the pill will only change the highest boost point, not necessarily eliminate the spike, just reduce it also.

The only problem is, that if they know you have changed the pills, I think that is "illegal" also.

I doubt it, but can you change the ECU?

DamonB

Can't change the ECU either. My understanding of spikes is that these occur when the second turbo comes online and the its pressure suddenly slams into the system. Won't decreasing the amount of prespool therefore lessen the spike?

DamonB

Too much sugar in your cereal this morning? I actually pulled up behind a yellow Aris K (aren't the ALL yellow? Seems like it) in Plano a couple weeks ago. I thought all those things had finally died.:p

airborne

a home depot boost gauge should do the trick till you can get an ecu...

Pressurized

If you can't use an ECU(which is pretty stupid, you might as well set fire to your car now) you'll have to get some sort of manual 'home depot' boost controller or add a restrictor plate in the exhaust to give a little back pressure....

badass7

www.dawesdevices.com This manual boost guage has eliminated my spiking. If you don't get that boost under control and bring it back to stock levels you will be sorry. If not, get an ECU. I have an M2 ECU for sale if interested. PM me.

Wade

iTrader: (1)

Check out my webpage at www.wvinter.net/~flanham/wlanham I have some information on there about adjusting your boost curve.

Wade

Toadman

Wow, never seen spikes with only 2 mods before. Can you fabricate a restrictor plate and mount it between the cat and DP?

jumprdude

I think an upgraded ECU will bump him out of ASP in auto-x. Yes, dumb, I know, but that's the rules.

Drilling out the pills will help.

DamonB

Living in Dallas gives me a great resource nearby: Rotary Performance. Explained my problem to Chris and he assured me all I needed to do was change the pill in the wastegate actuator. So I put in the new pill (think it is .07 something) and all is well. Boost pattern is now back to 10-9-spike to 11-10. Amazing how such a small change brings it down. The Home Depot valves must be SUPER sensitive.

pweizman

I am guessing you put in a holley jet #67. Is that correct?

Did you install it yourself?

Did you have to grind off the threads to make it fit in the tube, or will it fit? I am doing mine this weekend.

I am getting 10-9-12 with a DP/catback (it is cold here)....

Later,
Patrick

Kahren

iTrader: (13)

be carefull when u boost in teh cold u can run lean, coldair=dense air=more air

DamonB

I put it in. Don't know if it's a Holley jet or not. It's a brass rod about 1/4" long with a hole in the middle; only a teeny bit bigger than stock. Goes right in the hose just like the stockers. I am doing only 11 psi in the cold now.

pweizman

Cool.

Where did you get the little pill at?

Everyone told me to order the Holley jets....but the end seems pretty big to fit in the hose.

Later,
Patrick