I bought my 94 FD already modded with an aftermarket downpipe, midpipe and catback exhaust system.. I've done some reading around and have heard suggestions against using a midpipe without also installing a new ECU and/or a boost controller to regulate the amount of boost. Right now I don't have either of those, however I believe that my boost gauge peaks at about 10psi, maybe slightly higher full throttle.

As long as I don't modify the intake before adding a new ECU, am I relatively safe? I haven't heard any "knocking" as of yet, but I really don't know how to differentiate between normal engine sounds magnified by the loud exhaust and any sounds that may be symptoms of predetonation.

 

The new ECU, comes when you get the frontpipe. Or is it really a downpipe? A downpipe is from the turbo, a frontpipe is from stock turbo manifold..... If you have the frontpipe get an ECU.. I dont if its from detonation but I know you power sucks and runs like POOP!

 

No frontpipe, it's a downpipe, replaced the stock pre-cat.

 

get an ecu dood....or save money for a powerfc..streetport...fuel pump..injectors etc....

take yer pick...the fork in the road is now.

j

 

Any recommendations on what to buy and where to buy it? I planned on getting one eventually, however I can't afford it right now.. damn taxes and all :P Am I ok drivin it for awhile w/out one? I believe the previous owner drove it for about 10k miles as it is now and the engine still runs.. if it had problems with detonation the apex seals should have been toasted like a bagel by now.

 

Keep your boost limited to 10 and you'll be fine.

As far as ECU's, you have quite a few choices. There are direct reprogrammed ECU's offered by M2 and Pettit. There are also reprogrammable ECU's offered by Apexi, Haltech and some others..

If you ever want to upgrade your injectors, then you should go ahead and invest in a reprogrammable ECU. They are more expensive of course.

If you don't ever plan on upgrading your injectors or going to a single turbo, the reprogrammed ECU's will be fine.

 

I'd take it easy. Don't run the engine too hard. Keep the rpm's low. Until the ECU.

 

If you make modifications to air flow characteristics (exhaust included), it's good to get ECU modification to dump some extra fuel on the top end. You have to be more cautious when you're on the throttle so you don't overboost unless you have upgraded the wastegate (and turbo).

With the downpipe, you may experience faster boost rise time since you'll have better exhaust flow. Turbos make their power on exhaust (turbine side).

Just watch your boost gauge on the cool nights/days until you get an ECU (or fuel/ignition controller).

J