302/351 timing - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

wyvern · 10-23-2003, 19:32

I have a 302W mexican engine to be blown and installed in a Capri.

I received second-hand advice from someone reputed to be the retired cheif race engineer for a well-known Ford racing driver (also retired), which was: use 351 timing instead of 302 timing.

No-one I have spoken to can say why, most had no idea the older 302/351 had different timings.

What is the advantage of 351 timing (balance?), and should I be pushing for it in an 500hp-odd supercharged 302 with max RPM around 7000-7500?

BlownV8 · 10-23-2003, 21:05

have a look at your thread in the power adders section.

Volvord 784VC · 10-24-2003, 19:16

The difference is that with the 302 firing order cylinders #1 and #5 fire (the front two cylinders) in sequence which places a high load through the entire length of the crankshaft. The 351 and 5.0L HO engine #4 and #8 fire in sequence, because these cylinders are the rear most the forces are placed closer to the flywheel and greatly reduce the torsional load on the crank.

svo347 · 10-25-2003, 06:52

sweet Volvord I didnt know that....
Anything else you wanna share with me

Volvord 784VC · 10-25-2003, 07:31

Well I am not sure what things you may want to know, the author of this thread is targeting impressive power, but 500HP from a 302 block is pushing it a little. Even though the Mexican block does use a higher grade of cast iron there has been some problems with porus or weak areas, definitly have the block sonic checked. Ideally with a goal of that HP a Dart block or an R block would be the preference.

I am sure you are aware of upgrading the bottom end bolts, keeping deck height as tight as possable, and installing aftermarket heads as the stock heads do not flow well at all, especially on the exhasut side.

ebxr8240 · 10-26-2003, 05:55

Yes but finding a DART supplier here is the problem !!!
Yes I have found R 302 supplier but the dart needs less machining and arguably stronger for it has 5x 4 bolt mains.. Not that it's a serious problem with centre 3 being 4 bolt on R 302's..Hmm 8.7 deck height sounds o/k too on the Dart block...