Skip to content

Pontiac Engine Tech

Pontiac stroker kit with 4.25″ or 4.50″ crankshaft block clearance

Many people seem to be under the impression that there is a lot of work to be done to a stock block when installing a stroker kit. The most frequent question we get asked is “What areas on a stock Pontiac need to be clearanced when installing a 4.25″ or 4.5″ stroke crank?”

where to grind a pontiac block for a stroker kit before pic

The picture above shows you the primary area you will need to work on in order to make your 4.25″ or 4.50″ stroker crankshaft work in your stock block.  As you can see the area painted yellow with the screw driver pointing towards it is VERY close to the front crankshaft counter weight.  You will need a die grinder, some goggles, and about 10 minutes of time to grind this area back back.  We typically grind this area back so that we have at least a .080 ” gap between the block and the front crankshaft counter weight. 

After you are done grinding your block should look similar to the picture we have below.

any new part should be installed and all clearances checked prior to final assembly because of factory production variances.

Please remember that ANY new part to be installed in your engine should be installed and ALL clearances checked prior to final assembly due to factory production variances!

KRE Northwind Pontiac Intake Manifold Measurements

We frequently get asked about how the KRE North Wind intake measures up!  We have used this intake on engines making 500 hp to 850 hp and everything in between.

 

KRE Northwind Pontiac Intake Manifold Dominator Base
KRE Northwind Pontiac Intake Manifold Dominator Base

 

The following table of measurements was taken using a MR-1A Block with a set of stock KRE Aluminum D ports with Tin Indian Performance .060 thick intake gaskets.  All of the intake manifolds measured were in their original / unmodified form.    Measurements were taken off of the carb flange to the valley pan area.  Some of the intakes have tapered carb flanges.  All measurements are in inches.

 

Intake                                         Front Measurement      Back Measurement           Tapered flange?

KRE North Wind                                    9.622                             9.622                        No taper

Edelbrock Torker II                              8.176                             8.397                        Yes taper

Edelbrock Victor 4150                        10.868                           10.868                        No taper

Edelbrock Performer RPM                    8.932                           10.054                        Yes taper

Professional Products Hurricane        7.515                             9.268                         Yes taper

Edelbrock Victor 4500                        10.825                          10.825                          No taper

Pontiac Cylinder Head Bolt Torque Sequence

When we install a set of Aluminum Pontiac cylinder heads we use the following torque sequence pictured below.

 

Pontiac Head Bolt Torque Sequence

 

When we are tightening the heads up we typically do so using 30 wt oil for lubrication.  We also torque most of our aluminum heads up to 95 total foot lbs.  We do this in four steps.  The first step is to snug all of the fasteners up in the recommended sequence pictured above.  Step two is to tighten each fastener to 30 ft lbs using the recommended sequence.  In the third step, we go to 60 ft lbs. and tighten in the recommended sequence.  In the fourth step we go through the sequence one more time at 95 ft lbs.  We feel that this installation method gives us a very even tightening sequence and a very good head gasket seal.