Finished car:






I drove the car a lot last summer, and then put it up for the winter. It ran great, but I thought maybe I was a bit conservative on compression ratio, as I wanted to not have issues with pump gas and detonation I have on the 350 in my old Austin sedan.
So in January I was at a local swap meet and saw a pair of like new Dart SHP 180cc aluminum heads! Seller said they were on his drag car, and he upgraded to 215cc heads. I bought them for $700, so quite a discount over new prices.




Put them on the car, adjusted everything after replacing the stock pushrods with chromoly hardened rods to work with the guide plates on the Dart heads. About 200 miles later I began to hear lifters rattling, so I pulled the valve covers to adjust them. I have roller rockers, with poly locks, and all were tight, but there were some that had way too much lash! I ran out of rocker stud adjustment, and decided I better check pushrods. I pulled them all and none were bent, but all of them showed signs of contact wear at the guide plates! Certainly not chromoly that I ordered. I looked closer, and realized the metal worn off the pushrods was sitting in the heads, and looked like powdered graphite!
At this point I knew the engine needed further inspection, and a thorough cleaning. I pulled the intake, and all the roller lifters. Took the lifters to my arbor press and compressed each plunger/spring and found numerous were sticky from metal inside them, and one was collapsed with a broken internal spring!
So I ordered another full set of Howard's hydraulic roller lifters, another set of chromoly pushrods from a different supplier, and while I was waiting I did a complete clean up of the engine, and drained the oil, and filter. Washed it all out, and ran my priming tool in the pump to ensure I washed the diesel oil mixture through all the passages.
Reassembled the engine, set the lash, filled it with new oil, and new filter, plus a quart of Marvel Mystery Oil just for good measure. Fired it up, and set timing, but had to wait weeks to drive it with all the crumby rainy weather we were having. Finally got to start driving it again just a week ago, and everything seems to be great again. Dart told me I'd gain about 60hp and 50 ft. lbs. torque over the old 74cc LT1 heads, and up compression from 9:1 to 10:1. That puts the 350 at around 425 HP, and 420 ft. lbs. torque. It sure feels like it gained 60 HP, so I'm pleased with it now that it's finally OK again.

 

Can't believe it's been over 18 months since I looked in here, and done any update to this thread!
About 100 miles after I installed the new Dart aluminum heads I began to get lifter noise! I pulled the valve covers, and found excessive lash on two rocker arms! After agonizing over what could be wrong, I decided to pull the intake, and do a complete inspection of cam, lifters, and associated parts. I discovered every pushrod had wear on them where they contact the guide plates. I had ordered new hardened pushrods when I installed the new Dart heads, but appears I was sent standard non hardened pushrods! I pulled all the roller lifters, and found one collapsed, and three more with issues when I tested them by compressing them on my arbor press. They didn't easily spring back to static position, and after disassembly I discovered they had some fine debris in the lifter bodies.
I drained all the oil and removed the filter. Cut the filter open, but saw nothing in the oil or filter that I could see with the naked eye. I used my bore scope to inspect cam lobes and everything looked new there. I am fairly certain what was plugging up the hydraulic roller lifters was microscopic metal worn off the pushrods! So I ordered a new set of roller lifters, and washed the block out thoroughly by pumping diesel through the oil system. Then a second flush using cheap motor oil to get any diesel out of the oil passages. Finally I reassembled the engine with new lifters, pushrods, and then put new VR-1 oil, and a high capacity filter on it. I drove the car for a couple hundred miles, and dumped the oil again, and cut open the new filter to inspect it. All looked great, so another fill with VR-1 and another new filter. It's been great ever since, and several thousand miles on it since the repair was done.


Made a short list of winter projects to do this winter, and got the first one done Saturday. Well partially done anyway. I wanted to switch the front springs to another pair with more arc to them, but a couple hundred pounds lighter spring rate. So got the new spring packs installed, but then I couldn't reconnect the front shocks as the stance was 2" taller. So I have to remake my lower shock mounts to make them taller to accommodate the change in stance. Not a tough job as the lower mounts bolt on, so I'll remove them, and fabricate new ones.
Couple other small changes to the gas pedal and shifter, and it will be ready for another cruise season, and a trip to the nostalgia drags this summer.

 

Looks great.hope to see ya out there one of these days.

 

Do you get to Riverdale for the Oldtime Drags in August? I've been there many times with my red Austin gasser over the years.

 

No I haven't but I'd love to,August is a busy month for me,2 sons birthdays,my old gang reunion (sort of an anti - class reunion campout for us '70's hippies from high school daze) and the wife's family reunion. Not to mention our busy season at work. You going to the Portland Swap Meet? I'm thinking about checking it out if I can find time.

 

I never miss the Portland Swap meet! Even when I'm not building anything, or don't need any parts, I still go to both PIR and Expo. That's how I ended up with this '39 back in 2019. Sure wasn't looking for a whole project car, but saw this rotted out coupe dirt cheap, and next thing I knew I was pulling money out of my pocket. And I was almost done with the walk thru PIR when I found it.
If you go, expect a full day to walk each venue, and try to go the first day of each venue. PIR starts on a Thu. and Expo on a Friday. Last weekend of this month.

 

I've been a few times but it's been a while,if I find the time to go I'll give a PM here a few days in advance.