[ponyakr]

Originally Posted by PAUL K

I have one for you; how fast do you think Mrs. Shipp's 400 would run in a stock 67 Firebird? Maybe assume a TH400 and the performance gear ratio.

Quicker than that same car with absolutely "as cast" ports, on otherwise identical heads, is my guess.

So, are you saying that the heads on her engine have absolutely "as cast" ports ? Hey, I'm asking. I don't know. There's no possible way I could know.

It's just my thinkin that these 1st gen Pontiac Stockers couldn't run low 10's with D-port heads, which have untouched, "as cast" ports.

Don't it take around 500hp or more to run these times/speeds ? Will a legal '67 Pontiac 400 Stocker engine make 500hp ? More ? How much ?

To me, these are legitimate questions. I don't have a clue how to calculate the answers. But, I assume that some here can.

[ponyakr]

Since I brought it up, I feel obligated to post a little more info about Randi Lyn & her '67 Bird Stocker. Here are some quotes from the article, linked below the quote.

"...Running at 3,210 lbs. (with driver) in D/SA (11.55 index), the Pontiac has run 10.40 at 124 mph. And when set up lighter for C/SA, it's run a best of 10.31 at over 125 mph...

Amazingly, the Poncho sings to 6,800 before she clicks the gears, and it buzzes across the stripe where no Pontiac should go—revving to 7,800-8,000 rpm!...

rated by Pontiac at 325 hp and factored to 338 hp by NHRA. It's meticulously prepared to take full advantage of the Stock Eliminator guidelines and produces north of 500 hp..."

https://www.motortrend.com/features/...1967-firebird/

The article was published back when she only had 4 nat event wins. I think she now has 7. But, I don't think she's married yet. So, she's still "Miss" Shipp, & has never been "Mrs. Shipp". LOL

There are lots of pics in the article. One of 'em shows that the engine does indeed have 670 heads. And I assume she revealed the 500+ hp number, because she's seen the dyno numbers.

So, bottom line is that she shifts @ 6800, crosses @, or very near 8000, makes over 500hp, & has run quicker than 10.50's.

She even provided the ET, top speed, & total weight numbers, so you guys who know how to calculate stuff can do your thang.

Randi Lyn seems like a real nice lady, and their whole racing operation seems to be 1st class. So, she & her Pontiac are a couple of my favorites.

But, with all that said, I still don't have a clue if those 670 ports are "as cast", or not.

Here's another article, with less technical info.

https://dragchamp.com/2020/nhra/stoc...ndi-lyn-shipp/

https://dragchamp.com/2019/nhra/stoc...-66-nationals/

https://www.facebook.com/rlshipp

[Formulajones]

Originally Posted by ponyakr

..

rated by Pontiac at 325 hp and factored to 338 hp by NHRA. It's meticulously prepared to take full advantage of the Stock Eliminator guidelines and produces north of 500 hp..."

https://www.motortrend.com/features/...1967-firebird/


There are lots of pics in the article. One of 'em shows that the engine does indeed have 670 heads. And I assume she revealed the 500+ hp number, because she's seen the dyno numbers.

So, bottom line is that she shifts @ 6800, crosses @, or very near 8000, makes over 500hp, & has run quicker than 10.50's.

]

Easy to figure. If it only weighs 3210 with the driver, that's pretty friggin light, then it only needs a little over 500hp to run mid 10's. That's a pretty light car so it doesn't surprise me to run those times with a 400 and 670 heads considering all the other tricks they do. Don't need a dyno to figure that out, but it's a rough guess. One thing for sure as Paul has already said, they know how to use every bit of power the engine puts out.

The rules state they aren't supposed to play around with the ports, but nothing about what they can do with valve jobs, seat angles, and valves.

I already stated how Paul improved the flow of the heads I sent him with just his valve job tricks. The flow sheets showed as much as a 30 cfm gain. I'm sure other engine builders that do a lot of NHRA builds have figured that out too. Work within the rules.

So for conversation sake, if a 670 head flows 220 cfm stock, theoretically you might find another 30 cfm just playing with certain valves and valve angles if you know what you're doing.

With the low lift cam having tons of duration (square lobes I mentioned earlier) to take advantage, I could see the engine making some decent HP, and HP is just a math equation of torque production. With that said, even more interesting is that I'd bet torque production would be better than most other engines of that size and that's what helps move the car down track.
Boy this kinda got way off subject, lol. But interesting.

[Formulajones]

There is also a reason why you'll see that Pontiac combo more often in stock NHRA type racing than most other Pontiac combos. Seems those 670 heads have something better about them than most other castings. I've heard that from a couple of Pontiac stock eliminator guys.

[ponyakr]

Originally Posted by Formulajones

There is also a reason why you'll see that Pontiac combo more often in stock NHRA type racing than most other Pontiac combos. Seems those 670 heads have something better about them than most other castings. I've heard that from a couple of Pontiac stock eliminator guys.

Now, there's something else that's real interesting.

I have only known of 2 Stockers & 1 Super Stocker that are running 670 heads, in recent history.

LOTS more Stockers running a '68 Bird, especially in this century. The NHRA hp factor for the '68 D-port head 330hp engine has always been very similar to the '67 hp factor, as far as I know. So, I'd say maybe the open chamber #16 & #62 heads might have just as much potential as the 670 heads. Is there info proving that the 670's are better ?

There have also been lots of 4X head '74's & 6X head '77/'78's, that have run strong in Stock & SS. Many more than '67's.

"...I've heard that from a couple of Pontiac stock eliminator guys."

Just out of curiosity, were those guys running 670 head Stockers ? Unless one of 'em was Bryan Phillips, I'd don't know of any other guy who has run a 670 head Stocker, in the last 10 years. If there is one or more, I'd like to have that info.

[PAUL K]

About forty years ago I sold a virgin pair of 670 heads to a gentleman from another State. He seemed all hot and bothered to get them. He had me send them to Ellison Race Engines, which if I remember correctly were in Cincinnati. About three weeks after sending them I get a call back from the gentleman wanting to know if I had interest in buying them back. He told me Ellison said they were nothing special.

[Formulajones]

Originally Posted by PAUL K

About forty years ago I sold a virgin pair of 670 heads to a gentleman from another State. He seemed all hot and bothered to get them. He had me send them to Ellison Race Engines, which if I remember correctly were in Cincinnati. About three weeks after sending them I get a call back from the gentleman wanting to know if I had interest in buying them back. He told me Ellison said they were nothing special.

I'm familiar with Ellison, they were a big name decades ago around the Cinci area. They mainly seemed to build Chevrolets from what I remember and some good running Chevy engines came out of there back in the day. But like any shop they dabbled in everything. Saw a lot of their stuff running at Edgewater back then.

[Formulajones]

Originally Posted by ponyakr

Now, there's something else that's real interesting.

I have only known of 2 Stockers & 1 Super Stocker that are running 670 heads, in recent history.

LOTS more Stockers running a '68 Bird, especially in this century. The NHRA hp factor for the '68 D-port head 330hp engine has always been very similar to the '67 hp factor, as far as I know. So, I'd say maybe the open chamber #16 & #62 heads might have just as much potential as the 670 heads. Is there info proving that the 670's are better ?

There have also been lots of 4X head '74's & 6X head '77/'78's, that have run strong in Stock & SS. Many more than '67's.

"...I've heard that from a couple of Pontiac stock eliminator guys."

Just out of curiosity, were those guys running 670 head Stockers ? Unless one of 'em was Bryan Phillips, I'd don't know of any other guy who has run a 670 head Stocker, in the last 10 years. If there is one or more, I'd like to have that info.

The couple that I talked to were running 670 head combo's in later model pontiacs so different class but same idea. Have to look at other classes to find them. That type of class where a classic engine is run in a 3rd gen Firebird for example, they could run any model year engine/cylinder head package they want but choose the 670's, which I thought was interesting.

[ponyakr]

Originally Posted by Formulajones

The couple that I talked to were running 670 head combo's in later model pontiacs so different class but same idea. Have to look at other classes to find them. That type of class where a classic engine is run in a 3rd gen Firebird for example, they could run any model year engine/cylinder head package they want but choose the 670's, which I thought was interesting.

OK, that makes all the difference. That's why I wasn't aware of their cars. Those are "GT" Super Stock class cars.

Those engines go by Super Stock rules. More head mods allowed, plus unlimited roller cams & aftermarket intakes. IIRC, a GT racer posted that the ports in SS heads can be reshaped.

So, I won't even consider SS heads in this discussion.

BUT, I'd really like to know what cars those engines are in. I try to post info about all Pontiac powered SS cars that are entered in big races. BUT, for the GT cars, most lists do not post what engine is in each car. I've discovered several Pontiac powered GT cars, which I'd missed.

[Jay S]

If Shipp’s car is set up down to the minimum weight for C/SA the car and driver weight should be 9 x 352 HP = 3168 lbs. It mph’s at about 120 mph. That indicates closer to 460 HP by the et calculators I use. Ball park number…Working the old super flow HP equation backward that is 221 cfm @28”. What that car does exceptionally well is that first 1/8 mile, that is usually where S and SS are quick, the quarter et is mostly made in the first 1/8th. That 10.50 ish et is quick for a 120 mph blast.

300 cfm shouldn’t be that difficult of number to hit if someone put in the work on a d port. I am not sure how easy it would be on a 670, IRC they are known to be stronger flowing at the lower lifts versus other d ports. Without flow numbers at all the lifts it is really really difficult to judge how well and how long they would work for racing or on the street. Maybe it flows 300 but it is at .8” lift, 300 sounds awesome but if the cam doesn’t even have .5” lift the car would likely be faster with stock heads. Lots of people have went over 300 cfm with d ports. But they look something like this photo of these D ports of a friends, ran deep into the 9s NA in a 3200 lb car….bad azzzz set of d port heads.

[ponyakr]

"...9 x 352 HP = 3168 lbs..."

Not sure where you got those numbers.

According to the Class Racer Info site, it looks like the current hp factor is 338hp.

http://www.classracerinfo.com/Engine...4&MAKE=Pontiac

9 x 338 = 3042 + 170(for driver) = 3212 lbs min weight for C class, if I punched in all the correct numbers.

She said that in C/SA it ran a "...10.31 at over 125 mph..."

She said that in D/SA it ran "...10.40 at 124 mph..."

9.5 x 338 = 3211 + 170 = 3381 lbs min weight for D class

So, maybe 124 mph @ 3380 lbs will give you guys the numbers you need to make a closer estimate of power ?

Guessing they probably ran at least 20 lbs or more heavy, to be on the safe side. So, I'd use an even 3400 lbs for the D/SA min weight, when punching in the numbers.

When I punched in 10.40 @ 124 mph @ 3400 lbs, the Wallace hp calculator shows somewhere between 596 & 506 hp. That's quite a range, so I don't know how accurate it could be. What online 1/4 mile hp calculators do you guys think may be fairly accurate ?

http://wallaceracing.com/hpcalculatorquarter.php

This calculator says it'll take 506hp to run 124 mph in a 3400 lb car.

https://racingcalcs.com/quarter-mile-calculator/

This one also says 506hp.

https://www.tciauto.com/racing-calculators

Same for this one. Apparently, several of these are using the same formula, which, according to this site, must be "HP = (MPH ÷ 234)³ × Weight".

https://www.gregraven.org/hotwater/c...p-from-qm.html

IF this formula is close to accurate, Randi Lyn's engine has to be makin a little over 500hp, minimum.

[P@blo]

Originally Posted by Jay S

If Shipp’s car is set up down to the minimum weight for C/SA the car and driver weight should be 9 x 352 HP = 3168 lbs. It mph’s at about 120 mph. That indicates closer to 460 HP by the et calculators I use. Ball park number…Working the old super flow HP equation backward that is 221 cfm @28”. What that car does exceptionally well is that first 1/8 mile, that is usually where S and SS are quick, the quarter et is mostly made in the first 1/8th. That 10.50 ish et is quick for a 120 mph blast.

300 cfm shouldn’t be that difficult of number to hit if someone put in the work on a d port. I am not sure how easy it would be on a 670, IRC they are known to be stronger flowing at the lower lifts versus other d ports. Without flow numbers at all the lifts it is really really difficult to judge how well and how long they would work for racing or on the street. Maybe it flows 300 but it is at .8” lift, 300 sounds awesome but if the cam doesn’t even have .5” lift the car would likely be faster with stock heads. Lots of people have went over 300 cfm with d ports. But they look something like this photo of these D ports of a friends, ran deep into the 9s NA in a 3200 lb car….bad azzzz set of d port heads.

I picked up a pair of Butler ported 670 from a forum member here and took them in for new bronze guides and a valve job. The intake port shape is the same on my heads and looks a little square.

The machine shop indicated they flow a lot better than the 250cfm that I thought and called them a race head. Combustion chamber has been modified to an open back-woods modern version as well. The cc was 172 on the intake ports.

The 670 heads are pretty popular with guys so while they are just a normal D-port they can be a good head once modified. Something about the later cast heads have the larger combustion chambers that intrudes into the port turn.

[ponyakr]

"...Ellison said they were nothing special."

He should have known. For any here who don't know, Ellison did engine work for lots of Pontiac Stock/SS racers back in the day.

The 1st time I saw an Ellison decal on a Pontiac was on Truman Fields '68 Bird, after it won Stock @ Indy '73.

I recently saw both the Ellison & Fields names on an Angeles & McCarthy SS/IA '68 Bird. There was also an Ellison decal on the gold 2nd gen SS Bird which I think belonged to Bob Michael. It had Golden United Life on the side. IIRC, he said either his brother or brother-n-law sold that insurance.

When Truman got the '72 GTO SS sponsored deal, that car also had Ellison decals. That car was also a record holder. I assume that he used Ellison for all his Pontiac machine work, at least when he lived in that area.

[sdbob]

My exp with my stk parts SD455,35 yrs ago. Car weighs approx 3740. Heads were done by AHines Racing out of Lawrence burg Ind. He was doing engines for different Pontiac guys. Anyways I had some input from John Herslow.John said to run 4.56 gears. I tried them with basic slapper bars. Car was spinning,i tried adjusting shocks ex.just couldnt get good consistent times. So I put 4.10s in got car to 12teens at 110. Still not good. He had gone 11.70s. So we talked. He gave me a cam that he said went the fastest with,however he said car was popping through carb. I have cam but was afraid to use it. My point being you need all the dyno time, testing in car to find what works.Another you could estimate hp, work backwards car weight,mph get ball park figure for required hp. I do think heads are modified with acid to get the flow for the hp. I'm satisfied at my age if I was younger I would test different ideas. Automatic trans are in the $5k range I've been told,gulp! for me. Testing ,more testing.i will tell you for my SD that the qjet 2nd metering rods are very very thin,I picked up when I did that the engine wants fuel.

[PAUL K]

Originally Posted by ponyakr

Quicker than that same car with absolutely "as cast" ports, on otherwise identical heads, is my guess.

So, are you saying that the heads on her engine have absolutely "as cast" ports ? Hey, I'm asking. I don't know. There's no possible way I could know.

It's just my thinkin that these 1st gen Pontiac Stockers couldn't run low 10's with D-port heads, which have untouched, "as cast" ports.

Don't it take around 500hp or more to run these times/speeds ? Will a legal '67 Pontiac 400 Stocker engine make 500hp ? More ? How much ?

To me, these are legitimate questions. I don't have a clue how to calculate the answers. But, I assume that some here can.

My mistake I though she was married to Bo.

What you are asking in regards to the CFM it would take to run mid tens in her car is going to be tough to figure out. There is a whole lot more going on with the rest of the car than just what's under the valve covers (as you know). If you knew what the engine would run in a stock Firebird or known chassis it'd be easier to base line the power their engine is making.

I don't know enough about their combo to venture a guess. I'm certain, based on my past experiences is a lot of "class" racers seem to think ten horsepower that they paid $5k for is a better than ten horsepower they can buy for $500.... Regardless they do manage to squeeze a lot of ET out of their combinations. I'm glad a handful of them are flying the Pontiac banner with success after all these years.