Did any of the 400sbc have emission control systems? I am swapping a 305 4brl for a 400 and need advise??????

 

Yes there was smog on the 400s, why do you ask??



------------------
ASE Mechanic/Machinist/Smog Tech

1999 NBM Trans Am
1986 Chevy 3/4 ton pick up
1981 corvette
1995 Kawi ZX6R

R.I.P. #3
My favorite quote about D.E. "He can see air"

 

switching from a 305 to a 400??? my advice?? HOLD ON!!!!

------------------
89 firebird formula

356 10.5:1compression
comp cams xe262 cam
performer rpm intake
#1405 edlebrock 600
sportsman 2 heads 64cc 2.02/1.60 valves 200cc intake runner
msd 6al
h.e.i. proform 50,000 volt vac. advance ditributor
700r-4 with 3.08 first gear and 3.23 posi 7 5/8 rear end.
b trans shift kit(will kill shifts...suck dong!!)
shorty heddman hedders with custom 3" pipe y-pipe back(no damn cat!) with 40 series flowmaster!


future mods: 406 roller REALLY REALLY REALLY RADICAL!!!!!

 

Well someone said i have a computer and i thought my car didnt have one.They said it is connected to the carb and controls the fuel and air flow. Is it possible to bypas it?

 

Yes, you have a computer. (if the 87 in your sig is the year of the car.)

It depends on what you need to do if you have to comply with any smog regulations on what you can do to the engine.

A 400 is a good swap but you will want to open up the ex. system to help it breathe.

I'm not sure on how good the stock computer controlled carb will feed the 400, it would probably be fine, but to get the most out of your 400, you will want to open that up some to. (I can't remember if the center intake bolt angle was different in 87??...anybody??)

You will have a few headaches, for starters, the dip stick is on the drivers side on a 400. This will interfere with the dr. side ex. manifold. You will need to run headers.

This will also help cure another ex. problem with the 400s, they aren't set up for 305 ex. manifolds. The 400 heads only have 6 ex. bolt holes. The 305s use a seventh hole on the pass. side. But as stated, headers will cure this.

You can get a set of aftermarket heads that will work great,(the stock 400 ones suck), just remember to drill the extra coolant holes in them.

Now, if you don't have to smog it, its real easy, just go get a "one wire" HEI dist. and get yourself a nice performer intake, holley or edelbrock carb, (or whatever you choose) and a set of headers. Now you are rid of the computer comtrolling the spark and fuel mixture.

This has been done a ton of times on this board, there are a lot of people that can help you with this one.

------------------
ASE Mechanic/Machinist/Smog Tech

1999 NBM Trans Am
1986 Chevy 3/4 ton pick up
1981 corvette
1995 Kawi ZX6R

R.I.P. #3
My favorite quote about D.E. "He can see air"



[This message has been edited by Engineboy (edited March 18, 2001).]

 

Thanks for your help,the year of the car is 87.

 

don't forget the one piece rear main seal, an 87 will have a one peice rear main seal. 400 blocks have 2 piece rear main seals...

------------------
86 SC, 305 LG4, TH700R4, SLP headers, 3" cat and exhaust. Mild cam 204/214, .423/.442. SLP shift kit, richmond 3.73's w/limited slip. Susension Technique Sway Bars, Globel West Wonderbar, Poly everything bushings, Metco LCA's, Lakewood Panhad Rod. 16" ROH, with Toyo 245's. For autocross, 16" IROC's w/bfg R1's... Need more speed.....

 

Good point, you will need a different starter and flexplate.



------------------
ASE Mechanic/Machinist/Smog Tech

1999 NBM Trans Am
1986 Chevy 3/4 ton pick up
1981 corvette
1995 Kawi ZX6R

R.I.P. #3
My favorite quote about D.E. "He can see air"