[ponyakr]

This guy in NY has a '71 350 plus TH350 for sale. Has a Torker intake, plus an extra 068 cam, he says. The price is $250 OBO. Any of you 350 guys here live close enuff to NY to pick it up ? Might be REAL cheap, depending on what is the lowest offer he'll take.

https://www.facebook.com/nick.brigha...location=group

This FB page is listed with the ad for a 2-barrel 350, a TH350, & a 10-bolt rear end, all out of a '69 Lemans. Price listed is $500 OBO. It's in MN.

https://www.facebook.com/valeska.ols...location=group

[pmd400]

Originally Posted by AG

How about some JE 0.030: forged pistons with a dome?

Are they Pontiac 350 pistons?
I can’t find any info on that part number

[AG]

The pistons are 350P pistons, 0.030". They have a 0.980" pin and a CH of about 1.78" but is hard to measure with the dome. I bought them years ago from someone for a '72 350 but built a 455 instead and never used them. They are new with rings. Not sure of the net dome size, probably around 15-20 cc with the valve reliefs.

[pmd400]

Is there a part number on the underside of the Piston? Not the casting number that u photographed? With the part number JE can tell you the exact specs.
Thanks

[Formulas]

Facebook add from Pontiac racers page Richie Hoffman used Ross 350P super stock pistons. $150.00 call or text 516-316-5914 From July 28

Also on a Facebook page not long ago a guy was selling misc. Pontiac stuff no descriptions really beyond it's a short block and it was a 350 with TRW pistons in it for like $75.00
I already have a set and he was a couple states away

.

[ponyakr]

In case some of you guys don't know yet, Adam Strang is now running a 350HO in his '68 Bird Stocker. At a recent race, it ran a 10.847. No doubt it is the quickest 350 Pontiac powered Stocker ever.

https://www.dragracecentral.com/DRCS...r2019#indextop

And, that's with #18 small valve heads, low lift flat tappet cam, iron intake, & 750 Q-jet.

[AG]

Originally Posted by pmd400

Is there a part number on the underside of the Piston? Not the casting number that u photographed? With the part number JE can tell you the exact specs.
Thanks

No job number on piston.

[pmd400]

Originally Posted by AG

The pistons are 350P pistons, 0.030". They have a 0.980" pin and a CH of about 1.78" but is hard to measure with the dome. I bought them years ago from someone for a '72 350 but built a 455 instead and never used them. They are new with rings. Not sure of the net dome size, probably around 15-20 cc with the valve reliefs.

Are you interested in selling them?

[AG]

Yes, I'll try to determine the dome size first.

[pmd400]

Originally Posted by AG

Yes, I'll try to determine the dome size first.

Pm sent

[pmd400]

I wrote a couple of paragraphs as an update and the site logged me out again so all was lost.
In short. Checked a stock 350 block. Comp height of piston were 1.720. Pistons were .020 in the hole so dodge 1.74 comp height piston would be ok.
Machining of crank down to bbc journals and resizing small end of rod is not cost effective.
Autotec will make custom pistons if a shelf piston will work with minor change I.E small bore change, small pin height change, pin diameter change etc. cost is about $550 for flat tops. Trying to get onto somewhere over there who is willing to build them is also very difficult. So for a low budget 350 build with decent compression the dodge 318 flat top piston with 1.740 comp height on Pontiac rods is best

[pmd400]

So what I’m thinking of building is this. Stock block bored to 3.910. Use dodge 318 cast pistons on Pontiac rods. If I can find cheap reconditioned factory rods with arp bolts I’ll use them. Stock Pontiac crank, not cut under size. Rotating assembly not balanced. Dodge pistons/pins weigh 760g, stock Pontiac 350 weigh 790g. 7j2 heads milled 0.050 and 2.11 intake valves installed. Cam must be under .500 lift due to valve length and to ensure valves don’t hit top of block. Budget 1 5/8 headers with summit 2.5 exhaust. Th350. Rear gears currently 3.08 but willing to change. In a 72 firebird.
What converter/rear gears/cam would work best? How fast down the 1/4 could it actually go?

[Jay S]

Originally Posted by pmd400

So what I’m thinking of building is this. Stock block bored to 3.910. Use dodge 318 cast pistons on Pontiac rods. If I can find cheap reconditioned factory rods with arp bolts I’ll use them. Stock Pontiac crank, not cut under size. Rotating assembly not balanced. Dodge pistons/pins weigh 760g, stock Pontiac 350 weigh 790g. 7j2 heads milled 0.050 and 2.11 intake valves installed. Cam must be under .500 lift due to valve length and to ensure valves don’t hit top of block. Budget 1 5/8 headers with summit 2.5 exhaust. Th350. Rear gears currently 3.08 but willing to change. In a 72 firebird.
What converter/rear gears/cam would work best? How fast down the 1/4 could it actually go?

7j2, 96cc head? w/.050 cut probably 88 cc? Have you estimated where you will be at for the static compression? Lower 9s?

Personally I would keep the 3.08 gears, and get a 9.5” street/strip converter. A little more money than a 10”, but more efficient and slip less driving casually on the street. As a bonus the 9.5 can be set up to flash to the tq peak of the 350 and still be streetable. JMHO, go budget everywhere but the tq converter if you want the most out of your combo. Maybe low 13s?

[Jay S]

Cam?? FWIW, maybe an Ultradyne 274/282. 225/233 .468/.468 on a lsa of 110. Then buy a cheap set of oem ra 4 rockers. Suppose to be a 1.65, seem to run closer to a 1.6. Pushrod is further away from the fulcrum than the 1.65 compcams and prw roller tipped set ups. Lift would be very close to .5 with that cam and a ra4 rockers. Into the 9s some on the scr and a little work grinding on the valve pockets and I think a 350 could push 400hp easily. Drag radials and a good converter you could embarrass some of the 350s big brothers.

[pmd400]

I have 2 pairs of 7j2 heads. All measure about 89cc. Should be able to get them near 80cc.
Are the fti esr series of converters any good? They are 9.5 diameter and budget friendly.
Is that cam too big for a 350. I was thinking something like a voodoo 702. Bearing in mind a shift point of about 5500 due to cast pistons/rods

[ponyakr]

"... 7j2 heads milled 0.050 and 2.11 intake valves installed..."

Definitely NOT a good head choice, for several reasons. Would only use those if they're the best you can come up with.

I think they have press-in studs & no end header bolt holes, nor pads for any holes. Don't need 2.11 intake valves. small intake & exhaust valves are just fine for 350 engines. There are 11 sec Stockers & 10 sec Super Stockers running 1.96/1.66 valves.

"...88 cc?...estimated...static compression? Lower 9s?..."

At zero deck height, no-relief pistons, & .039 x 4.3 FP head gaskets, I get barely over 8.5 CR, using this calculator.

http://www.wallaceracing.com/cr_test2.php

"...Ultradyne 274/282. 225/233 .468/.468 on a lsa of 110. Then buy a cheap set of oem ra 4 rockers..."

IMO, that would be a bad cam choice, because:

(1) Ultradyne cams are now custom grind only. So, price is probably about $200 plus shipping.

(2) Too much duration for a stock stroke 350, unless the car is strip only.

(3) No need for more than .468 lift.

(4) A 112° or higher LSA would give the cam a broader power range, plus a little smoother idle & more vac--more streetable.

Now if we're talkin a strip only car, that's a different app altogether.

Higher stall speed converter & numerically higher rear gear ratio will produce a lower ET. If car will be street driven, then the stall speed & rear gear ratio will have to be a compromise of some sort.

"...a 350 could push 400hp easily..."

Would be tuff to get a streetable 400hp, out of a stock stroke 350, with only 8.5 CR.

This '69 350HO rebuild only made 330hp. And that was with #48 big valve heads that had only 66cc chambers. Hard to believe that JUST a larger HFT cam would increase the hp by 70. And, if you increase the size of the chambers to 88cc, you'll lose some of what you gained with the larger cam.

400hp is real easy with a 455. Not too hard with a 400. But, it takes a little more to get a 350 up near 400hp. And, a cam that will make 400hp, in a 350, will not likely be real streetable.

Hey, as some say "Anything is POSSIBLE." But, a streetable, 400hp, low CR, stock stroke, 350 Pontiac engine, will take some very careful planing, & probably a lot more money than most would be willing to invest in it.

Just as a side note: Adam Strang just ran some 10.80's, with his 350HO powered '68 Firebird Stocker. So, if you got the money, a quick Pontiac 350 is doable.

[ponyakr]

"...measure about 89cc. Should be able to get them near 80cc..."

Changing from 88cc to 80cc, I get 9.26 CR.

Are you sure those heads have never been cut ? Most of the head charts list them at 96cc.

http://www.bassettracing.cz28.com/custom3.html

"...How fast down the 1/4 could it actually go?..."

We went low 13's. Brad Koivisto's '74 GTO Stocker runs low 11's, Bill Rink's '74 GTO Super Stocker runs high to mid 10's, and, as mentioned, Adam Strang's '68 Bird Stocker runs 10.80's.

So, considering the differences in the engine you've described, and these drag engines/cars, along with the extra weight of a '72 Bird, I'd say that a high 14 would be something to shoot for, unless you wanna go strip only.

Most of the common Musclecars from the year '72 would probably not run in the 13's without a few mods. There were actually not a lot of 13 sec factory street cars, after 1970.

Guys on this site tend to think a current street Pontiac should run high 11's or quicker. But, I can say from experience, you can have lots of fun, with a 13/14 sec street car, & even win bracket races, without running any quicker than that.

[Jay S]

I would call FTI and talk to someone, tell them your setup. Is this what you were looking at?

https://ftiperformance.com/Economy-P...erters_c80.htm

Some of the converters such as a 9.5 from PTC claim it will have cruise slippage is a percentage of the stall speed. It would be worth a call to talk to someone at FTI. It might work great.

It does look like a big jump to go from the hp of the 350 HO at to 330 hp to 400 hp. You certainly need more compression than a scr with an 8 in front of the decimal point. Cam wise I just through a cam and it’s specs out just to look at. Not recommending that Ultradyne necessarily. It would be fun though with a nice converter.

One persons “strip only cam” is someone else’s spirited daily driver. A Lunati 702 would work great imo. The last 350 Pontiac I did had a single pattern solid roller with 260@0.050, it handled the big cam pretty well imo. A L-89 350 Chevy had a cam around 222@.050, even through the smog era. Most guys are plenty careful about overcaming a 350 Pontiac. I still like that Straub cam once mention in another thread in a 350 for the street. Summit 2801 is still the cheapest and would do well if you want to have a 14 to 15 second ride with a stock converter.

[Jay S]

Out of curiosity, what are the NHRA S/SS factors for the 350 4 bbl and HO engines? Seems like those are good references for what hp potential was versus some of the factory ratings. Example would be like those sbc L-89 350s from the mid to late 70s had a hp factor up in the 300+ range for hp, IRC.

[pmd400]

Sorry. Heads are 7h1. Stock are 89cc. Should be able to mill to 80cc. Car still needs to be streetable. I’d honestly be happy with high 13s. If I can do that with a mild cam, mild gears and mild converter then great. Iv still got the straub cam. It does have less exhaust then intake duration. Won’t cost anything to try it.