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Hey guys, could use a little advice on cam recommendations. I posted earlier this year about my 1979 350 rebuild and finally it's coming together after various block and crank setbacks.
Summary: '79 Olds 350 block bored 0.030" over, no milling to the decks. 3A heads with stock valves and FelPro head gaskets. Pistons are SpeedPro flattops.
Assuming the 3A heads are 75cc, that puts me at 9.1~ compression. The heads are currently being crack checked, CR might bump up negligibly if they need to be 'cleaned up' a little.
I know cam technology has changed over the years; can anyone advise on a good match for this combination? I'm not looking for anything crazy; end goal is a FWD cruiser with a power bump over stock. Thanks!
Great questions. The pistons are the L2320(F30) set.
Stock intake with factory '79 Quadrajet. Exhaust will be a single 3" with high-flow cat.
The car is actually an '85 Eldorado, so the trans is a 325-4L (basically a FWD 200-4R). Gearing is 3.15:1, stock converter. Trans has OD and TC lockup.
That carb will need tuned, especially on the idle circuits with more compression and cam, very lean from the factory. Figure out your piston to deck and head CC along with the head gasket thickness for your actual compression ratio. You have over a 3 to 1 final drive and assume a similar stall to the 2004R, which usually stall in the 1900 rpm range. Not terrible for a mild cam. Good luck.
Last edited by olds 307 and 403; April 12th, 2022 at 07:57 PM.
I don’t think you’re going to have 9.0:1. I’d figure 8.5-.8.75:1. I’d cam it for that.
A good single pattern with 210@.050 or less would work. However I’d normally do it on a 108 but with your combination I’d spread that to a 112lsa.
Just my opinion.
Got the 3A heads back last week and checked the combustion chamber volume, it was very close to stock at 75 cc. Pistons went in today and are 0.025" in the hole. With the Felpro gaskets, I think 9:1 is still within reason.
I used a 214/214 .472/.472 on a 110 LSA with 9 to 1. It worked quite well with a 2200 to 2500 stall and 2.78 gears. It would do 1/4 block, one wheel peels. Do you know the final gear is? I assume the torque converter stall is pretty low.
I used the compcam 212 in a low compression olds 350 and it ran great. Nice idle, good vacuum, had the stock converter, and good power. I wouldn’t put a stall converter in it. You just don’t have enough gear for it. Just my opinion.
Last edited by joesw31; May 6th, 2022 at 04:29 PM.
I find most 2004R came with the D9, flash about 1900 rpm, higher than the TH350 stock. It is stamped all around the edge of the converter, if stock. Yes, I agree on a better converter. The 2200 to 2500, which flashed 2350 flash stall was a massive improvement vs a stock TH350 1600 flash stall with a 2.78 gear and a 25" tall tire with the 21l4/214 cam.
Last edited by olds 307 and 403; May 6th, 2022 at 07:12 PM.
Thanks guys. It's definitely a low-stall converter in this 325-4L (stamped #5, though google isn't turning up a conversion chart). For my kind of driving, I can live with that. I had the same trans/converter numbers behind a used 403 years back and the biggest problem was traction : ) I was running a Seville MPFI intake on it with the old analog ECU (modified to run a little richer). Fun setup.
Go figure, the Comp Cams 42-228-4 212/212 is on back order pretty much everywhere. Looking to get this dropped in the car and running by the end of the month. Might have to make a few calls tomorrow.
Not D5, is it? That is the high stall in H/O and 442. The Erson to TQ20 is similar as is the Lunati high efficiency series 270/270, if you can find either. The generic 204/214 cam is also an acceptable cam in a 9 to 1 350.
I don’t think you’re going to have 9.0:1. I’d figure 8.5-.8.75:1. I’d cam it for that.
A good single pattern with 210@.050 or less would work. However I’d normally do it on a 108 but with your combination I’d spread that to a 112lsa.
Just my opinion.
Not D5, is it? That is the high stall in H/O and 442. The Erson to TQ20 is similar as is the Lunati high efficiency series 270/270, if you can find either. The generic 204/214 cam is also an acceptable cam in a 9 to 1 350.
Here's a pic of the converter, just a '5' stamped all around it. Originally behind an HT4100. Google hasn't been much help, though one generic chart suggests 5=Medium Stall.
Just an update... I narrowed down my options to the Erson TQ20H (E54021). Out of Stock. I liked the Lunati "260/260" (210/210) and "270/280" (204/214). Both of those Out of Stock. I called Comp Cams on the 42-228-4 (212/212 - 110LSA) as their website said 'Unavailable - Shipping Soon'. I was lucky #14 in the queue...eventually learned they were waiting on blanks with no forecasted ETA.
No surprise, nobody actually carries this inventory, it's all 'shipped from manufacturer', so when they're out of stock, they're out of stock.
I can get my hands on the Edelbrock Performance Plus 3712, which is 204/214 @ .050 with a 114 LSA. Good? Bad? Ugly?
I have used that Edelbrock cam and Melling version as well, which is also currently available. Get either one, basically the same cam, so get whatever is cheaper.
Last edited by olds 307 and 403; May 10th, 2022 at 07:59 PM.
Just an update... I narrowed down my options to the Erson TQ20H (E54021). Out of Stock. I liked the Lunati "260/260" (210/210) and "270/280" (204/214). Both of those Out of Stock. I called Comp Cams on the 42-228-4 (212/212 - 110LSA) as their website said 'Unavailable - Shipping Soon'. I was lucky #14 in the queue...eventually learned they were waiting on blanks with no forecasted ETA.
No surprise, nobody actually carries this inventory, it's all 'shipped from manufacturer', so when they're out of stock, they're out of stock.
I can get my hands on the Edelbrock Performance Plus 3712, which is 204/214 @ .050 with a 114 LSA. Good? Bad? Ugly?
Thanks guys. Just ordered the E-brock. The Melling version is also out of stock everywhere. Also tried Dick Miller, no luck there.
Is there any harm running this cam with stock length pushrods? (rest of valvetrain geometry is unchanged, Felpro head gaskets add a touch)
BTW, reason I ask is that the online spec suggests longer pushrods "may be needed"; I suppose it's ground on a smaller base circle. I see Chevy 5/16" PR's are 0.050" longer than the Olds. I have to order new PR's either way, and unfortunately don't have a measuring tool. Everything else is "stock". Hyd lifters (new), stock springs, rocker arms, etc.
Last edited by eldofever58; May 11th, 2022 at 01:52 PM.
I ran the stock non adjustable valve train and stock length push rods. Check the rocker arms for wear, replace if any amount of wear.
I have the Edelbrock 204/214 cam in a 1971 Olds 350 that is otherwise stock in a street rod weighting 3600lbs. Has 7 heads which have not been removed and original valve train including push rods. Supposed to be 8.5:1 compression. Trans is 2004R with stockish TQ converter. Tires are 28" tall with 3.42 posi rearend. Runs okay but not a barn burner. Will lay 12 feet double strips of rubber from standing start but doesn't really pull strongly to 60 mph. Decent gas mileage at 18 mpg combined driving using 625 street demon carb.
Idles smoothly with 17-18 inches vacuum at 700 rpm.
John
Last edited by JohnTN; May 15th, 2022 at 06:47 PM.
Reason: Additional info
Good info, thanks John. Lots of manufacturers claims out there, so it helps to get some real-world feedback.
I did find an inexpensive source for the BBC intake pushrods so they're on the way. Cam is in hand, so we'll see how things stack up against the factory PR's.
April 12th, 2022, 10:46 AM
