What's the difference?

[swta]

What\'s the difference?

Hello All,

What's the difference between '73-'86 and '87-'91 K-5 motors, other than the TBI? I'm looking to purchase a dual exhaust kit for my '86 K-5, but the Flow Master exhaust kits are only for the '87 and later trucks. Is the difference in the '87+ heads, or is it a difference in frame / chassis? Basically my question is....Will the '87 and later Flow Master kit fit an '86 and earlier K-5?

Thanks

 

[Blazer_Boy]

Re: What\'s the difference?

'86-'91 motors basically have different sealing issues resolved. One piece rear seal, centerbolt valve covers, different center intake bolts, etc. My only guess would be the transfer case. In '87 I believe the switched to the NP-241 transfer case, along with a different crossmember. I doubt that minor detail would hold things up though.

 

[95 Silverado]

Re: What\'s the difference?

does it list the kit for a truck, or specifically for a k5 Blazer. the 73-87 trucks and blazers shared the same front frame and driveline, after 87 the trucks went IFS and the driveshaft moved to the left side while the blazers stayed the same. consequently 88 and later truck parts don't fit blazers of the same years.

 

[Bubba Ray Boudreaux]

Re: What\'s the difference?

'87's still had 208s. I think the case was changed in 89 or 90.

 

[swta]

Re: What\'s the difference?

The kit P/N 17161 is specifically for the '87-'91 K-5 Blazer...not P.U.

 

[95 Silverado]

Re: What\'s the difference?

GM began fuel injecting the engines (TBI) in '87 (I think) that kit could have the provisions for the o2 sensor where the earlier kit would not, but the later kit would probably still be usable on the older trucks.

 

[swta]

Re: What\'s the difference?

 

[trailblazer87]

Re: What\'s the difference?

87 is the first year of the tbi, chevy changed heads in that year, so anything prior to that won't seal right. Other than that its the same front to back.

 

[dyeager535]

Re: What\'s the difference?

I don't think thats correct. Only difference should be the intake manifold pattern on the heads. I've got a pair of TBI exhaust manifolds here if I need to measure anything. I believe the O2 bung would be the only difference.

 

[trailblazer87]

Re: What\'s the difference?

If thats it then just cut a hole and weld a ring for the sensor on and go.

 

[Pure Insanity]

Re: What\'s the difference?

I have read the whole thread and just about everything covered here is listed right here .