hi, all. i'm going to do a B16a swap into my 1990 Si. now, i know everything i need, BUT does the header/downpipe match up to the cat or will i need a longer cat? i've heard yes and no. btw, it's a 1st gen B16 and using a Hasport mount kit. thanks.

btw, ordering motor from jspecjdm.net

 

IF you are using stock B16 header and stock SI catback then it will need to be modified. I had to take mine to a muffler shop and have the fwd cat flange extended and it also needs to be turned. Make sure you use thoes spring bolts when you reconnect the flanges.
J-DUB

 

thanks. that helps me a lot with what i need to know.. is there any way i can get a "bolt up" setup like using a 99-00 Si cat? just throwing out a suggestion. thanks.

 

I know this post is old but I also have the same question..
I'm doing a b16a1 in my 88 rex and when I do the swap I'm buying new headers and a high flow cat.
What headers and cat should I buy so that they all bolt on together to my greddy exhaust nice and neat and what not??
Please and thank you.