A few oddball technical questions and answers...

[silver12r]

My answer: Summit racing has wrinkle paint in black, red and blue. I bought the red stuff, experimanted with it and got the wrinkle just right. I also bought a GM orange (I took my valve cover in and matched it up) and sprayed over that while it was still a bit tacky. The color and finish match absolutely perfectly and it's solid as a rock. I'll let you know if I encounter any durability issues.

My question: I just put on a straight exhaust(no cat, no can), BOV, K&N, new intake gaskets and reset the ECM on my 1990 SE and it pops and backfires like a madman. Anyone know the potential cause of this?

[ErnestM]

My question: I just put on a straight exhaust(no cat, no can), BOV, K&N, new intake gaskets and reset the ECM on my 1990 SE and it pops and backfires like a madman. Anyone know the potential cause of this?

Lack of O2 sensor on the exhaust?

ErnestM

[silver12r]

The O2 sensor is there but it's running mostly over .5 V and the knock signal counted 9 in about five minutes of running. She's been parked for a while so I'm pondering a bad gas scenario....

I mussed with a few hoses and wonder if perhaps I haven't undone a vaccuum hose someplace?

[cnh1990]

You might see a neat flame out the back pipe. I have seen pictures of an 4 cyl. Esprit with straight pipes and under certain conditions you will have flames shoot out the back. It must sound a bit loud. During test I ran my car without a muffler it was loud. But it was in my garage and not on the road. I did at one time blow of the coupler to the muffler while on the hwy it did sound nice but never heard it from the outside as I was driving.
Calvin

[ErnestM]

I believe (but am not sure) that the standard engine control maps expect a CAT at the very least. Therefor, it may be making changes in your timing because of the emission that it is observing. Just something to consider.

ErnestM

[grungex]

My question: I just put on a straight exhaust(no cat, no can), BOV, K&N, new intake gaskets and reset the ECM on my 1990 SE and it pops and backfires like a madman. Anyone know the potential cause of this?

If it pops and bangs when you let off the gas, this is normal with the straight exhaust. Mine does the same thing, I have only a Micklewright exhaust, no cat.

Cheers,
Sanj

[silver12r]

That's exactly what it's doing. Thanks again Sanj!

[cnh1990]

Hey Sanj,
Do you get a flame out the back like with just the muffler like our friend with the X180R?
Calvin

[espritnutdean]

My 88 spits a flame when coming off throttle , I think it happens when it pops, I have the stock exhaust but I have punched out the cat and put a pipe through it. Still passes emissions. He He.


Cheers,
Dino 88turbo

[grungex]

cnh1990 said: Hey Sanj,
Do you get a flame out the back like with just the muffler like our friend with the X180R?
Calvin

Sometimes. He's running a lot more fuel, so his probably does it more often. I can get flame just by revving it up at a standstill and letting off the gas quickly. It's also amusing to startle other drivers by goosing the throttle and letting off quickly, often it will make a nice pop ;-)

Cheers,
Sanj

[5150neo]

Make that two of us. I just finished building the same exhaust based on Neil's design (with no cat) and I get the exact same results.

John