454 new long block timing questions
 

Hello - I have a 1989 squarebody K3500 cab and chassis with a 454 engine, SM465/NP205. I just bought a stock long block for it. I don't have any of the emissions on it. I added a Weiland Warrior intake designed for use with the peanut port heads. I am using a rebuilt Quadrajet carburetor (this truck was carbureted from the factory). I just got the engine to start briefly last night. I need to know what I should be setting the timing at and or anything else I need to know about getting it running smoothly. TIA!

Re: 454 new long block timing questions
 

Pardon my ignorance but is that a roller cam engine or a flat tappet?
Your answer can determine what break in method to use.

Re: 454 new long block timing questions
 

Flat tappet. Sorry, I should have mentioned that!

Re: 454 new long block timing questions
 

You’ll need to do the normal 1500-2000 rpm cam break in procedure then. Don’t let it idle anymore until that is done. Big blocks like to eat cams!
Your choice of cam might influence what you set your timing at.
Do you need to limit your timing for warranty purposes?

Re: 454 new long block timing questions
 

X2. They do eat cams. Been there.

Once it fires, get those rpm’s up for 30 minutes. Don’t fiddle with the timing too much during break in. After break in, you can set timing to the specs of whoever built that long block. Anywhere from 8 to 12 degrees BTDC most likely.

Re: 454 new long block timing questions
 

I have to get it set somewhere to run though right? When it fired up it sputtered and stalled out almost immediately.

Re: 454 new long block timing questions
 

Just another quick question, why do I need to get the RPM's up for so long? They told me to vary my RPM's during break in. Also, just FYI, I am using a high zinc break in oil.

Re: 454 new long block timing questions
 

You get rpm’s up because the cam and lifters get their oiling from oil splash. And the lifters need to rotate and mate with the lobes. The time needed is related to heat needed. Takes awhile for the oil to heat up.

Re: 454 new long block timing questions
 

Final adjustment on that big block is going to be TDC with the throttle body injection. You can massage it to maybe 2 btc, any more than that then the computer may start getting weird with the programming unless you have the chip reprogrammed

Re: 454 new long block timing questions
 

Do the best you can to get the distributor dropped in at 0* - manually roll the engine to #1 TDC and get the roter pointing at the #1 wire on the cap. Once it starts get the RPM up to 2,000 ASAP and vary the RPM between 2,000 and 2,500 for at least 20 minutes - this will get the lifters spinning and splash oil on everything! Once you are done with that initial run, change the oil and filter and again use a high zinc oil or zinc additive. I just did this on a 400 SBC and 383 SBC both with flat cams and had no issues on break-in.

After the break-in run, you can set the timing and make any carb adjustments.