Big block in a k5 ?

[84k5oleyeller]

We just dropped the body on my buddy's k5 yesterday. The 454 valve covers are really close to the fire wall. My dad was talking about having to beat in the fire wall due to the blazer never being equipped from factory with a BBC. Did anybody have to relocate engine mounts/cut the fire wall to make it fit.

Sorry I didn't get a close pic of how close the motor is to the body

 

[Bent77]

Well the factory valve covers are rounded over a lot more. Ive seen a lot of Rat motors in K5s, but never paid much attention to the clearance

 

[diesel4me]

Though they probably didn't make any big block K5's,if a big block will fit in a pickup it'll fit in a Blazer--you may need the right combination of motor mount brackets for the engine and bolt them in the right holes on the crossmember ,and yes,the valve covers do come very close to the firewall,but factory ones should clear ok...

A friend of mine and I put a 396/402 from a '71 Monte Carlo into his '75 K5 and it fit,it was a tight squeeze,but once it was in there nothing rubbed or touched (except the headers,on the front shackle bolt)..the oil pan was real close to the front crossmember,but you could fit a finger between it still..

Note the picture below,that shows the BBC using different bolt holes than a SBC..
Also,GM made some special angled valve covers for BBC Corvette's that may help if you have clearance issues with the power brake booster,but you probably wont need them,I've seen many with "normal" valve covers that fit fine..

 

[obijuank5]

It's cause you have big ass valve covers.
Stock valve covers fit great and clear the brake system so you can remove them easily.

 

[nvrenuf]

The engine compartment of a Blazer is the same as any other model square body of the same year so there are no fitment issues. As stated, it's the aftermarket accessories like tall valve covers that create issues.

I've got a 454 in my 91 with zero problems. I do have a 1" body lift but I decided to use that for ease of working on the underside of the truck (bellhousing bolts, exhaust, clocked tcase, etc).

 

[Big Ray]

Raise the tranny a bit, rock the front of the motor down...

 

[84k5oleyeller]

I think it's the valve covers as well...he has a 2" body on it that seems to have made it a little better...just wondering if anyone had a problem before.

 

[6872xtc]

So I can't see for sure, but is the t-case crossmember spaced down?
If so, do what @Big Ray said...

 

[76zimmer]

Check the angle of drivetrain, shoot for 4* or close to it.
How tight is the distributor?
You should have no firewall issues if your angle is good.
I used DIY4X competition mounts....they are stout pieces!

 

[wheels87k5]

Check the angle of drivetrain, shoot for 4* or close to it.
How tight is the distributor?
You should have no firewall issues if your angle is good.
I used DIY4X competition mounts....they are stout pieces!

Are these what you are talking about? If so, I may be purchasing a set for the 454 Vortec I'm after.

 

[obijuank5]

Yes that's them. 10 points to anyone who knows what truck that picture is from. Throwback for sure.

 

[sweetk30]

not mine I use stock with energy suspension inners.

 

[76zimmer]

Yes that's them. 10 points to anyone who knows what truck that picture is from. Throwback for sure.

YOURS?

 

[76zimmer]

mine w/ Kerts mounts, and hydroboost not vacuum.

 

[Hoss7979]

I run the stock SBC motor mounts & have tall valve covers & no issue....

 

[max 02]

Mine is a stock 454, no body lift, didn't move the mounts forward,and used factory engine mounts for a small block, fits no problem.

 

[udy2554]

Tight, but it fits!

 

[Ronald L Graves]

The engine compartment of a Blazer is the same as any other model square body of the same year so there are no fitment issues. As stated, it's the aftermarket accessories like tall valve covers that create issues.

I've got a 454 in my 91 with zero problems. I do have a 1" body lift but I decided to use that for ease of working on the underside of the truck (bellhousing bolts, exhaust, clocked tcase, etc).

View attachment 227781

The suburbans come out the factory with big blocks and there are no clearance issues.

 

[6872xtc]

The suburbans come out the factory with big blocks and there are no clearance issues.

This was only in the 2wd ones which has the engine set forward when compared to 4wd.

 

[Ronald L Graves]

This was only in the 2wd ones which has the engine set forward when compared to 4wd.

I have a 81 K5 2wd im losing the 305 and going with a 454.