Lessons learned on engine built

typhoon

Member
Joined
May 24, 2001
Learned a few things while assembling. Thought I may post so future people may run across during search.

Hotair motors have

Different cam bearings
Oil Pan gasket (is obvious and I knew this one already)
Head bolts Uses ARP 123-3601 NOT 123-3603

You would think being is same head, the bolts would be the same. In my searches here, gathering part #'s I didn't see any threads mentioning it until AFTER I had the new bolts. O well.
 
i believe the holes in the block are different depth- shallower.i also found out something reguarding a olds 3.8 86 block and a buick block. the head bolts on the olds are larger and longer for the same 8445 heads. i believe the buick bolts are 9/16 and shorter-the olds were 5/8 and longer. when trying to put on a set of buick 8445 heads on the olds block with buick bolts-they would not even catch the threads.weird that a normally aspired olds 3.8 had heavier duty head bolts than the buick from the factory.the olds bolts were at least 1" longer.-go figure?
 
I got new ARP bolts, and they worked great. Heads are now on.

I would say lenght was upwards of 1" different.
 
STICKY IT!!

Souldn't there be a STICKY on this subject? Would be very informative to peps:cool:

Nick
 
Originally posted by 49-blues
i believe the holes in the block are different depth- shallower.i also found out something reguarding a olds 3.8 86 block and a buick block. the head bolts on the olds are larger and longer for the same 8445 heads. i believe the buick bolts are 9/16 and shorter-the olds were 5/8 and longer. when trying to put on a set of buick 8445 heads on the olds block with buick bolts-they would not even catch the threads.weird that a normally aspired olds 3.8 had heavier duty head bolts than the buick from the factory.the olds bolts were at least 1" longer.-go figure?

I could be wrong but don't think Olds ever made a 3.8L motor. The 86-87 Buick 3.8s had deeper threads that started farther down in the block than the 84-85 Buicks. Don't know if they're stronger but it reduces the chance of cracking the deck and lessens warpage.
 
In a 86/87 N/A olds cutlas ,the G bodies had alot of 3.8 s- whether they are olds or buick- dont know ,probably buick- All i know is from the factory the olds headbolts are heavier duty on a NA 2 barrell engine than on the buick 3.8 turbo motor- find an engine, pull out a headbolt and measure against a 3.8 turbo block and you should be quite surprised. my 86 cutlas also had all the body bushings-even the #5 gnx bushings that neither of my 3 turbo cars had.Bottom line is the olds headbolts put in from the factory were wider 5/8" vs 9/16" and about 1" longer , so if anybody was to build a NA block in a turbo application they might be better off getting one out of a 86/87 olds cutlass just for the better clamping force.HTRH- just remembered the buick block i was comparing the 86 olds block to was an 84 buickblock.- that would explain it- just get an 86/87 6109 block.
 
As far as I know Olds DID make a 3.8L I should know I have one in my 87 Cutty. My uncle informed me that Olds and Buick both made the 3.8L carbed engines for G-Bodies in those years. I don't remember the difference but the Olds were more reliable and the "better" of the 2 for whatever reason.

I'd also like to mention that my olds is the SLOWEST car i've ever driven in....:(
 
I don't know, wish someone could verify this but in all the years I've been going through the junkyards, the only 3.8L in a G-body I've ever seen has been the Buick motor. Whether it's a Cutlass, Gran Prix, or Monte Carlo it still uses the Buick V6 if it has a V6.
 
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