Your cam is 216*/228* at .050, 110* LSA. It is a small cam. You couple that with high static compression, and it is no wonder it is detonating. That cam is closest to the TA 212 for the 350, https://www.taperformance.com/proddetail.asp?prod=TA_212-350 218*/230* at .050, 110* LSA The power range is 1500-5500. Your 1650 stall converter is low for that cam. It should be around 2000-2200. Everything is combination. If one part of the combination is off, the resulting performance suffers. Having to use a a .070 head gasket to crutch the problem isn't something I would do. It might be a better idea to use a bigger cam. I would use this cam, https://www.taperformance.com/proddetail.asp?prod=TA_290-94H-350 With a .040 head gasket, your static compression would be 10.08:1, but your DCR would be 7.64 The idle would be lumpy, but coupled with a higher stall converter, it should be fun to drive.
Larry, that's a mistake on my part. I have already converted. I fill up with 95 octane in Germany, equivalent to 90 octane in the USA. Then there's 98 octane in Germany, equivalent to 93 in the USA
Really should look at another torque converter. You can try retarding cam 4 degrees in calculator and see if it it changes dcr enough. That with a thick head gasket to make up for the milled heads. Not really the answer but might be able to make it work.
Larry, which stall converter can you recommend for the TA-290-94H-350 camshaft? Stall and brand (TA-performance, TCI......) I don't know if it matters, I have a TH200R4 with a gear ratio 3.42 and we drive the following speeds in Germany City 30-35 mph Highway 50-65 mph Interstate 65 - open end (mostly between 65 and 85) Oh yeah, my intake valves are bigger than stock (1.875) 1.94 The exhaust valves are smaller than stock (1.550) 1.50
I would never buy an off the shelf torque converter. You are better off having one purpose built for your combination by someone familiar with Buick engines. This is what I recommend, https://www.v8buick.com/index.php?threads/updated-torque-converter-program.278923/ I have a 9.5" converter from Jim. Stalls around 3000-3200 with sticky tires. Jim built it as tight as possible because I also have a Gear Vendors Overdrive that brings my final drive to 2.76. You barely know you have a converter until you stomp it. Jim also builds converters for the TH 200, 700 4R transmissions. Call or PM him.
