Finally ! Progress On The 302 !

To recap my original issues. I built a 302 using a 91 SC T-Bird block. Forged Scat Crank and balanced the assembly. Mahle Forged Pistons, Forged Rods. .040 over bore. Was using a TFS Stage1 Roller Cam, AFR 185 Ported heads, Harland Sharp Pedestal Mount Adjustable Roller Rockers. Using 10w40 Valvoline VR racing Oil.
Oil pressure at idle cold is 70 and 45 Hot. C-4 Trans with GearVendors Overdrive and 3500 Stall.
One issue was lifter noise and the other issue was lack of low end power.

Remedy for the lifter noise after trying 4 brands of lifters it turns out it was the 4 Weak Springs on the new heads. So, sent the heads back and get a replacement set and removed all the springs and checked install height and ending up shimming 13 valves to get them at or within .005 of the recommended 1.810 height.
Then I checked the seat and open pressure of every spring and they were great.
This got rid of the valve train noise.

Next I put a degree wheel on and check the LC of the TFS Cam. I know I should have done it when I first installed but I can't really say why I did not. The cam was at a 113 Lobe center when installed dot to dot. According to the cam card it should have been 107.5° or 108° if the cam had advance from the factory which it apparently did not. When I advanced my crank gear 6° it was now at 107°.

This would explain my lack of low end power. This is a prime example of why it is so important to degree your cam. Nothing is consistent anymore these days. I even bought a set of expensive name brand lifters and I will withhold the name. One of them was not oiling so after taking it apart I found that there was no hole drilled in the inner piston of the lifter.

I called and Talked to Chris at Comp Cams and gave him the grind numbers I worked up and got the cam in a week. That did the trick ! Now this thing will fry the tires.

The moral of this story is when you buy a part that is supposed to bolt on like my heads were. Take them apart and check them over real good and last but not least, always degree your cam.

Manufacturers do not and cannot put loads of QC in a product and keep the cost down. Keep this in mind when buying a budget product. Some might say that 1600.00 for a set of SPF heads is not budget but when you spend 2000.00 each of some of the pro series head you will find that they have gone through an extensive QC process and they will be spot on.

Have a Great day !
 
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Thank you for sharing that! Sometimes we (myself included) think that we do not need to double check our brand new parts. With mass produced parts a QC dept may only check 1 in 10 or 1 in 100 depending on volume produced. Things get by them, they are human after all, right? Even the QC dept where I work can get too busy to check things out in detail, he will assume the person did the job right, which has resulted in a part being rejected during final assembly.

:cheers: