what would you do

[TEAMJACOB]

my 351w has a vibration in the motor, so ive been told. it has a ton of goodies in it but the fact remains, there is a vibration. if i had the money to have the motor pulled and rebuilt, i would but i dont. i drive the car every day but that vibration shows up in the higher rpms. im tired of having a car i cant have fun in. what would my car be worth as is? should i consider parting? selling off the 351 stuff to fund a 302 or something going in it? im open to suggestions. 91 hatch 351 efi, spyder intake, aluminum heads, t5, 5 lug conv, grey on grey. obviously a whole lot more done to it but i didnt want to list everything if it was necessary

[91CoupeMike]

Vibration from where?

Its probably something to do with the balancer or flywheel.

If you're using a stock style balancer. Throw it in the trash, they are garbage.. I fought with a vibration at higher rpms for a long time.. Bought a summit racing balancer approved to 8,000 rpm and it's smooth as hell. The balancer on there before was a dorman from Autozone, and I returned that pos.

[TEAMJACOB]

Vibration from where?

Its probably something to do with the balancer or flywheel.

If you're using a stock style balancer. Throw it in the trash, they are garbage.. I fought with a vibration at higher rpms for a long time.. Bought a summit racing balancer approved to 8,000 rpm and it's smooth as hell. The balancer on there before was a dorman from Autozone, and I returned that pos.

its a summit sfi balancer. new. the motor wasnt balanced before it was built

[FRANCISCO308]

Why didn't your builder Balance the motor? Have you tried another balancer?

[1bad91]

How much for the longblock? PM me. Thx

[TEAMJACOB]

Why didn't your builder Balance the motor? Have you tried another balancer?

im not going to go into. more simple to say its my fault. yes on the balancer question.

[TEAMJACOB]

How much for the longblock? PM me. Thx

its a 351 stock crank and rods. forged pistons. pro comp aluminum heads, comp cam, 42 lb injectors, 90 mm elbow, 90 mm tb, anderson power pipe, lightning maf, spyder intake. make offer in pm but it has to be enough to buy me a cheap truck daily or enough to put a 302 in so if your offer isnt enough, i wouldnt waste the time.

[91CoupeMike]

How cheap of a truck daily?

I'm about to have my explorer going and the day it starts, it's for sale.

72k miles, 2wd 5 speed 4 door 91' explorer. All new a/c, new radiator, brand new tires.. Thing is clean... CLEAN.. Dipshit blew the motor.. Some I'm putting in another one as we speak.. 12x,xxx miles.. If it doesn't run 100% I won't sell it because I'm cool like that.

Also open to trades for 4cyl beater car. Or a clean 99/00 civic 4door or hatch. Engine failure? No problem! I happen to have a good sohc vtec.

[jyro]

what balance balancer did you use?

28 or 50?

[DriveWayBuilt]

Want to trade long blocks ? Fresh 302 pan to intake. Still at machine shop

[91GriggsGT]

The 351W should be a 28 oz balancer. The flywheel should also be a 28.

Not real sure it will make a difference since you did not have the motor balanced to begin with. New parts, different weights of everything, etc. Thats why you ALWAYS balance a motor when you rebuild it.

If it really is a balance issue, I would stop running that motor before you do some real damage, if it has not already happened.

If I am not mistaken, didn't you have True Street do the motor? Maybe call them?

[slow84lx]

My guess is that your vibration is not coming from internal parts of the shortblock, but instead from a supporting part. Don't give up on it, keep searching until you find the problem & fix it. You'll be glad that you did.........and be really pissed if you put another engine in and have the same problem only to discover it to be a simple issue like a worn motor mount

[FOKAI]

Did you put the guide pins back on flywheel? That would cause vibration also. If I was you i would keep trying to figure it out. You don't want to go backwards from 351 to 302. Good luck bud.

[91GriggsGT]

Good point slow84lx. If I am not mistaken, an out of balance motor will vibrate like a sumbitch right when you start it, almost like it is going to fly apart?

OP, do you get the vibration if you are sitting still or is it when you are driving?

Also, any suspension mods that could change the angles of the drive train?

Is it a little vibration or a lot?

Like slow84lx stated, don't give up and maybe expand your search to the supporting parts and not just the motor.

[SEB]

I would change out the Balancer before throwing the towel in & pulling the motor. One of my mustangs had a bad vibration that started at 3800 rpms & I changed my balancer & it pulls smooth all the way to 4800 rpms now & picked up alot of TQ out the hole