Hi Simon
search for my thread "Black Bettys new lease on life".
When I took my manifold off it was warped too,after cutting the webbing out the warp was reduced to less than 1mm,it de-stressed it.I didnt machine it.I drilled the outer holes too to allow extra moovement.
Goodluck
Andrew

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LandyAndy

FAT BAZ,REST IN PEACE MATE!!!!!

Black Betty 1999 TD5 Disco and matching DIY off-road trailer
Classic Rangie(her ride) warm4.6,LPG,Wolf management,F/R ARB lockers
The Toy Series3 109 302V8 Auto(Project)
Stage1 V8 Van