Jump to content
HybridZ

Chevy 90 degree V6


Guest We Bad

Recommended Posts

The 4.3 L Chevy V6 shares many features of the Gen I small block V8.  The oil filter mounting pad is on the left side and the starter is on the right side of the block.  

 

The dry sump oil pan I'm using has a full length kick-out on the right side.  That is, the right side of the pan is extended 2" outboard of the pan rail mounting holes in the block.  This, combined with the scavenge oil line fittings being on the right side, prohibits the usual right hand side mounting of the starter.

 

Since my external oil pump allows me to relocate the oil filter, I fabricated an adapter to mount the starter on the left side of the block. Being only six cylinders, and not high compression ( 10:1 CR, supercharged), I can get away with the lightest starter Tilton makes.

post-30774-0-70342400-1361421335_thumb.jpg

post-30774-0-30326700-1361421353_thumb.jpg

post-30774-0-02110500-1361421378_thumb.jpg

post-30774-0-05347200-1361421395_thumb.jpg

post-30774-0-52989600-1361421424_thumb.jpg

Link to comment
Share on other sites

  • 3 weeks later...
Motor mounts:
The V6 block shares the same three-bolt mounting pad design as the 1st generation SBC V8, but the mounting pads are 4.4" closer to the rear of the motor.  With the engine in the setback position (as close to the firewall as practical) the stock crossmember engine mount towers are too far forward to be used.  Hence, they were removed.  In my case it was a moot point:  the towers interfered with the belt drive for the oil pump.
post-30774-0-05204900-1363059024_thumb.jpg
Motor mounts were made from 1/4" thick plate, 2" square tubing (1/8" wall) and 2 1/2" X 2 1/2" angle (1/4" wall), TIG welded together. They fit between the engine and the top of a polyurethane vibration damper which bolts to the top of the Datsun frame rail.  The polyurethane damper, one per side, is an Energy Suspension Transmission Mount, part #3-1108.   It features an interlocking design that prevents the mount from separating even if the polyurethane fails. 
post-30774-0-34642100-1363059080_thumb.jpgpost-30774-0-75956400-1363059091_thumb.jpg
The right side mount is offset to the rear to clear the oil pump.

post-30774-0-98252300-1363059127_thumb.jpgpost-30774-0-19813900-1363059145_thumb.jpg

Link to comment
Share on other sites

Those headers posted on the previous page look really cool going through the fenders like that!!!  Was there any issue with the exhaust  being too close to the tires ??

Edited by _X_
Link to comment
Share on other sites

This is not really six cylinder tech, but it relates to possible heat issues with fenderwell headers.  I saw this car at a local car show several years ago.  I was quite impressed and told the owner so.  Unfortunately I didn't retain his name so I can't give credit where credit is due.

 post-30774-0-63695000-1363477440_thumb.jpgpost-30774-0-28995800-1363477482_thumb.jpgpost-30774-0-07380700-1363477510_thumb.jpg

I think this is very tastefully done, kind of like the 1963 Corvette.  

Link to comment
Share on other sites

Nicest fender vents I have ever seen. If heat soak was a problem, vent the hood and let it out? I had heat soak trouble at the strip with just an L6 with pacesetter headers-that's how I justified my cowl induction hood! Better yet, your car is so cool, you should just run a hood delete-we all want to see that motor anyway.

Link to comment
Share on other sites

  • 1 month later...

     As Luigi mentioned in post #6 of this thread, most high RPM/high horsepower V6's run a common pin, odd-fire crankshaft.  Such a crankshaft is shown below. 

 

post-30774-0-06596400-1367417498_thumb.jpg

 
     The three crank throws are spaced 120 degrees apart.  But since the cylinder banks are oriented 90 degrees to each other (like a V8) the cylinder firings alternate between 90 and 150 degree intervals.  Hence the "odd-fire" designation.
     Jaguar used a 90 degree V6 with a common pin crankshaft in the XJ220.  The 3.5L twin turbo produced 542bhp and made the XJ220 the fastest production car in the world in 1992. 
 

    The production Chevy 4.3L crankshaft is shown below. 

 

post-30774-0-10013500-1367417735_thumb.jpg

 

    The rod journals are offset 30 degrees to each other to give an even 120 degree interval between firings.   

 

 

 

Link to comment
Share on other sites

  • 2 months later...
  • 4 years later...
  • 1 month later...

I put a 383 cu in SBC into my Z car in 1995. It soon became apparent to me that the car needed less weight more than it needed more horsepower. I was aware of the Chevy 4.3L V6 since the debut of the GMC Syclones and Typhoons. https://www.caranddriver.com/archives/gmc-syclone-vs-ferrari-348ts-archived-comparison-test

 

The NASCAR Truck Series was also using V6's at the time. Factory involvement means factory subsidized research and development and high tech exotica as close as your dealer's parts counter, such as this 74 lbs engine block with massive 4-bolt main caps and the capacity to go as large as 320 cu. in.

V62.jpg

Link to comment
Share on other sites

  • 3 weeks later...

The link in the previous post is really part 2 of a two part article. 

The 1st part can be found here:  https://www.powerperformancenews.com/tech/the-missing-link-v6-cam-test/ 

 

The race parts from GM were for 4.3's without the balance shaft.  None of my engines have the balance shaft.  This link sheds some light on the balance shaft that GM incorporated to smooth the inherent unbalance of V6's.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...