Ive got a 88 GTA with blown motor and I keep finding alot of rebuilt 350's but there all Pre 86 or 87 blocks. What would I have to change to make my accesories bolt on them?
also would the ballancer and flexplate be differnt?
thanks

 

The accessories will all bolt on just fine.

I think that the balancer may work, but the flexplate will not.

 

As long as the heads are newer than like 1972 or something - if the heads have the bolt holes you are good to go.

 

sweet thanks

 

It will all bolt right up if the heads are newer than 1969 castings (first year for accessory holes in the heads). Just make sure you use the right water pump - the one for a serpentine system spins in the opposite direction as one for a V-belt system.

 

Some members have had to drill and tap. Check the following link:

https://www.thirdgen.org/forums/tech...elt-setup.html

JamesC

 

The harmonic balancer will go on but double check the orientation of the keyway slot and the timing mark. On the newer 86ish and up the timing mark was at 12 o'clock while the older motors used a 2 o'clock position. Either balancer will work fine if you have the correct timing tab on the motor. Also the bolt pattern at the back of the crank is different for the flexplate/flywheel.

I'm using a 70's block with the serpentine setup and it works fine. I do recall one hole missing in the heads for the one bolt but I left it as is with no problems for the almost 2 years its been together.

 

yep same with me i have a 77 motor if you get an older motor and it has the flexplate with it, that will work. as far as serp goes , windowrattler is right the pass head is missing the one bolt hole for the a/c bracket. but thats ok cause you have two thick bars that bolt to from the exhaust man to the bracket and also one from the intake to the bracket. plus the two holes by the balancer and one in the block across from the water pump and one in the head, so there are plenty of bolts holding it together. i would nt even bother with drilling and tapping the one hole


oh and also that is right. you do have to change the water pump. the serp set does run opposite of the older set ups. the only thing i had to change when i did the swap was get a water neck that had the fitting in it for the other heater hose, cause the older motor has the fitting on the water pump, the serp style doesnt. or i think you can also run the heater hose to the other side of the intake if your intake has that plug there

 

Here's a link with helpful info, including the GM kit manual with instructions (which may not be exact, but will give you a general idea of all that's needed):

https://www.thirdgen.org/forums/afte...rsion-kit.html

JamesC

 

OMG - $829 for the serp kit? I just sold mine to a guy for $50!

The March stuff is much nicer and costs way less, and it can be done serp.

If you don't have the serp brackets already, hunt the local JY's or go March and save several hundred!

 

Wow, the kit has gone up considerably since I purchased it. The kit is nice because, not only is it complete to the last bolt but also because it provides the alt., water pump, and condenser. Can you find cheaper? You bet. But if you're **** like me, however, new is great. There's a pic in my vbGarage (lower left below)

At any rate, take notice of the instructions, which will likely be helpful.

JamesC

 

Id like to add one note of caution on drilling the inboard hole into the passenger side head. Use a drill stop and do not go further than 5/8" you not only will get into a water jacket but can also go through into the cam valley space and create an internal coolant leak thats fun to repair. BTW, James C. I very much appreciate your signature.