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Hello BP worshipers.....you have a new peer amongst you.


So the BP I have on the engine rack is a BP4W with solid lifters. I'm also fitting an aftermarket cam......


Its going to be a raod car......probably will live somewhere around 5000 6500 rpm when the going gets exiting......might get up to 7000-7200 on the occasion but its certainly not going to live there. But it all depends how the cams turn out.
I have 65lbs springs lined up for it.
cams are 238@0.050 with 10.4mm lift


It looks as though the cam has a 34mm base. And it needs calibrating. I believe the shims are 27mm? and come in various thicknesses. i'll need to replace 16 shimms for this. If I decide to go for shimms.

Ive seen shims for like $12.50 each thats like $200

1. what about under bucket shimms......is it worth the extra cost? cause it means new lifters....right?
2. does anyone have a recommendation for flat round shimms? where to get them from?
3. with the significant extra thickness of the round shimms (ontop of the bucket) make it more likely to dislocate?

StanTheMan wrote:1. what about under bucket shimms......is it worth the extra cost? cause it means new lifters....right?
2. does anyone have a recommendation for flat round shimms? where to get them from?
3. with the significant extra thickness of the round shimms (ontop of the bucket) make it more likely to dislocate?

1. Under bucket shims are good if you are continually running really high revs, which you've mentioned you aren't.
fwiw, my track car lives its life at 7200rpm and I just run normal shim over buckets even with higher lift cams, and have done for years now with no issues..

2. Chris from Precision Shims in Croydon Victoria. Ph 03 9723 0199 or www.precisionshims.com.au.
Fast efficient service. Can often post out same day if reqd. I've used him on many occasions and always had great service..

3. If anything a thicker shim would be less likely to dislodge than a very thin one...

rascal wrote:

StanTheMan wrote:3. If anything a thicker shim would be less likely to dislodge than a very thin one...

Correct. Ask Deckspeed how I know.

cool thanks chaps

I was silly enough to do this first. I should have waited until headshave & valve seating

Valves are between 0.1- 0.2 mm further in after getting the seats & valves recut.

x2 for Chris at Precision Shims. Talk to him first.