Putting TII secondaries(550cc) in my N/A will do what for me? Will just having the injectors give me more fuel or would I need a fuel pump and/or something to control it. This question is for in the way future if I ever need any more fuel. Actually right now I think I am running rich. Thanks.

 

I have a TII fuel pump and 550 cc secondaries and Im still running very lean in my 90 GTU. It takes a lot of mods to put the n/a's to a point where they need bigger injectors, but I am past that point.

Actually, Im looking for another pair of 550 cc injectors from an 89-91 TII. If anyone has any they wouldnt mind parting with, PM me.

 

what year are the 550 secondaries going in? my 91 has the same injector for all 4 while my 86 has smaller secondaries. what are the stock ones flowing at. i thought 86 -88 primaries were 550. and 89-91 were 550 all the way around.

 

I believe the 86-88 at least used 460's in the n/a primary and secondary. The turbos used 550's in the primary and secondaries. I put 550's in my 87n/a secondaries, and I have no doubts that it runs a darn site faster, on top end especially. That said, John Gibson wrote and said I needed to get some type of fuel controller for them to be effective. Got me. He's been around and doing rx longer than I. I still, seat of the pants know its faster. Just have Mazdatrix dual from front to rear and a K and N. The K and N don't do much for me. Probably just me. Not sensitive enough. If you go out to my car tonite while I'm sleeping and put the 460's in the car, I guarantee that I'll know it when I drive to work tomorrow. There! My story and I'm sticking with it.

 

I am actually going for the same exact setup on my 88 GXL Hailers. Got the K&N & am saving for the true dual exhaust. Is it worth it getting the 550s for the secondaries? Does it hurt your gas mileage? O ya, what can you beat with your car with those mods? Thanks.

 

All non turbo FC's came with 4 460 cc injectors. All turbo FC's came with 4 550 cc injectors.

Most people will run very rich above 4K rpm with the 550 cc secondaries on a n/a. The stock ECU compensates for the increased airflow from mods. The MAF sensor tells the ECu how much air is going into the engine, and the n/a MAF sensor is accurate to somewhere between 210-230 bhp, after which its maxed out. As for the n/a fuel system, it isnt getting close to being maxed outuntil around 200 bhp. Some people might gain a little extra hp in the top end from the 550 cc secondaries on a n/a, but without serious mods, you wont see much of an improvement unless you were running lean before the bigger injectors.

After I got the true dual exhaust, power woul fall off at about 6k RPM. It felt like the car had hit a brick wall, it just had NO power. I put the 550 cc injectors in the secondaries, and then I could easily pull past redlinbe, all the way to the fuel cut at 8600 rpm. But Im still running lean. My plugs are very light tan, with lots of white.

 

So does that mean once I get the true-dual I should look for some 550 secondaries?

 

I doubt you will need them after just intake and true dual exhaust. I have a lot of mods besides that.

 

Alright thanks.

 

Just revisited this post. Answer: Get the 550's. Well worth it.