i am getting the following:
K&N-57-3009 (cai)
dynomax-173663 (cat back exhaust)
edelbrock-68563 (headers)


my question is this i have been told by a few people to not go with a high flow cat. im sure several people on here have them is it worth it? i was told that since it flows more it tricks the O² sensor thinking its running rich and will adjust the a/f ratio to lean it out. also i was reading posts about air injection and someone said the RPO for air injection is K18. i didnt see that RPO on my sheet or i didnt see a pump anywhere on the framerail by the radiator on the passengers side. so thats 1 less thing to worry about. after i get these in my truck ill get a jet stage 2 chip.

 

Recently I was planning on replacing the OEM converter on my '91 Blazer with a Magnaflow high flow catalytic converter to see if I could squeeze some more HP out of The Blazer. I called the local mufflershop that was the dealer for that particular brand and the manager told me they quit installinghigh flow converters and only sell CatCo converters.The reason he gave was that they turn on the SES light on too many of their customer's cars. Hedid not elaborate but I was told later by a "expert" thatit was because the O2 sensor registers a lean condition and signals the computer to richen the fuel - air mixture, which canmelt a catalytic converter substrate when unburned fuelignites and burns in the catalytic converter. He continued to say that EPA requires that OEM catalytic converters to beoperationalfor 80,000 milesat 2000 degrees andaftermarket replacement catalytic converters aredesigned to last 25,000 miles at1200 - 1500 degrees.

I don't know how well the federal law is enforced but it is illegal to replace a perfectly good OEM catlytic converter without documentation from the local/state emmisions control program that it needs to be replaced. Another condition for replacement on the OBD II ('96 and later) vehicles states that theOE manufacturer's 8 year or 80,000 mile warranty has expired.

A dynometer comparison made with a OEM cataltic converter and a "test pipe" (straight through pipe), indicated 1 to 2 HP gain with the test pipe. Is it worth spending $150 for 2 HP and risk a ticket or emmission check failure?

 

i put a magnaflow on my 96 with a dynomax catback and had no problems at all. Made it sound a little deeper and helped a smige with mpg.

 

duntov i noticed you have a 63 catalina. i have a 69 gto judge but someone put a 428 in it somewhere along the way. you dont see too many pontiac people mostly chevelles,camaros,mustangs,.....

 

Pontiac enthuiasts are fading fast. That is because GM has not made a Pontiac V8 engine since 1978 when there were20,000 Pontiac engines remaining for the 1979 model year. I have two '63 Catlinas. One is a fully restored show car and the other is a unusual optioned unrestored survivor. It is really a "barn find"because I found it in Illionis in an oldgarage covered with dust. In three days, I got it running and drove it back to Dallas Texas.

I have now taken on a new project......a 1991 S10 Blazer 4WD SUV but it is inmint condition and only needs reconditioningwith new OEMparts. This will be much easier to to do since 1987-1994 GM ansd AC Delco parts are still available from many on-line suppliers.The only problem I will have is theweird V6 4.3L engine and I certainly do not want to put a V8 in it....

MyBlazerhasthe best V6engineto restore ( in my opinion )and make improvements on because it does not have that goofy balance shaft. This weekend, Iam replacing the master cylinder, rear brake drums, shoes, rear brake springs, wheels cylinders, rear brake hose and will flush the 18 year old brake fluid. I may replace the rear backing plates with 2-piece backing plates if I can get up enough energy to pull the axles to remove the OE backing plates. I have already finishedthe front brakes using ceramic pads (foralloy wheels) , slotted and crossdrilled rotors and new brake hoses.

What purposeare those aftermarket "Wheel Cylinder Retainers" for anyway? They are NAPA part number UP 25851 (Raybestos) . You must drill two holes in the backing plate and the axle housing flange to mount them.I don't thinkthey are OE on any Blazer with rear drum brakes.

 

not sure about the wheel cylinder retainer. but if you need a good forum for your pontiac go to www.pyonline.com (performance years)if thats not the right site then do a search for performance years. there are a lot of knowledgeable helpfull people on there. they also have a for sale section on there. so if you need anything for the catalina youll have a good chance to find it there. they also have a catalog to get parts as well. i dont have anything bad to say about that site. i used to be a hard core chevy guy until i got my goat and i have done a 180 to pontiacs. they were really ahead of their time and chevy couldnt do anything to hang with them.

 

I have been a member of Pontiac-Oakland Club International for 31 years. I have two double car garages full of obsolete 1961-1963 Pontiac parts, engines, pistons, cams, heads, etc. I am getting too old to chase obsolete car parts anymore so that is why I accepted my daughter's immaculate 1991 Blazer SUV as gift. She bought a new Honda Pilot...

I think I know what the "Wheel Cylinder Retainer Kit" (NAPA UP 25851) is for. The rear brake cylinders are retained in the brake backing plate by a round spring clip and the wheel cylinder pistons are not slotted to fit the brake shoes. In case the brake cylinder come loose from the clip, the aftermarket retainers will hold it in place.That is because most wheel cylinders are held in place by two bolts instead of the rinky-dink O-ring clip.

 

ya that makes sense. if you come across any 428 parts let me know. i know its not in that era but im always looking.

 

Don't mess with thoseold 428 Pontiac engines. By today's standards, they are not that good.A 455 Pontiac engine isis much better and has gobs or torque for driving on the street. Both of the 1963 421 engines in my Catalinas have been converted into455 engines by boring the 1963 421 block .060", installing a 455 crank, std. 455 pistonsand a mild cam.All rebalanced of course. Rebalancing a 455 engine is not absolutly necessary because you will not have to spin iit faster than 4700-5000 RPM to get a 4100 lb. car in the low 14s and be able to run with the GTOs. I have proved it many time with a consistant 14.30 ET on vintage M&H Racemaster 9.00-15, 11" cheater slicks..

"The only stubstitue for cubic inches is rectangular money "

Getting morepower from thebig vintage V8 engines is aneasy task. I have a much more formidablechallenge now. Thatis getting more power from a 1991 4.3L Blazer engine with less than $3500 to spend,keep the ECM happy and keep the engine compartment bone stock in appearance.

 

ill take a 428 over a 455 any day. a guy i knew had a 70 judge with the 455 and i would walk away from him. the bore/stroke ratio is better.