Author Topic: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?  (Read 5411 times)

4wheeling79

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #120 on: September 13, 2018, 11:10:58 AM »
Yellow1098 I'm with you I have a similar build going on in a 78 I have a 461 9.3 compression, 6X heads ported flow in the low 240 range, Comp HR 230/236 .510/.521, Typhoon single plain I hadn't decided on what headers yet. When I built the engine I just wanted 400hp but now I have changed the build a little and also going back with a 4L80e. I wish I had dyno numbers I could post but still hadn't made it to that point. I hadn't fully decided yet but was considering more cam and maybe a set of ported aluminum heads. I want a drive anywhere car that will run as good as it looks. So when someone says "will this thing move" I can say "oh yea"

yellow1098

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #121 on: September 13, 2018, 07:17:14 PM »
Thank you oldskool glad your back on the thread after the craziness haha....those 11's are the goal...working on exactly what your saying....with my aluminum 87cc heads researching which cam and from who get it from now....I can probably handle alittle less "street able" than most guys being it's just my hot rod

4wheeling...we are on the same page exactly...my car sounds like a beast and looks great so just looking to get the performece up to that...checkout those links I posted earlier and ull know what I mean....where did you get your stroker kit? And what cam were you thinking?

79T/Aman

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #122 on: September 13, 2018, 07:42:42 PM »
Firstly Dave 79T/Aman....thank you so much for the phone call this morning and the advice and chats about my car. Also your parts and setup are awesome and what I will always use on my car...you are a class act and a real resource to all of us and as 4wheeling said you have nothing apologize for. As far the thread going off the rails....I was alittle bit disappointed as I really was looking for answers and advice on this motor build to get to my goals....which I would like to mention I did receive about the intake I should go with the cam options I have and which are best as well as the stroke size. Those technical questions are what I was looking to discuss....70Ra did provide some answers there... but I do agree the street racing only hammering was out of bounds....there is a time and a place for that but it should be obvious the intention of this post was to discuss best option to reach my goals....I do like performance and racing but alittle common sense should be incorporated though it was slightly entertaining.....I would love to keep the conversation going like 737 just did....thank you all as always for your help and advice

Thank you.
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4wheeling79

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #123 on: September 13, 2018, 09:36:19 PM »
The stroker kit I got from Butler Performance I have talked a good bit with Jim Butler about the build. The cam I also got from Jim it is a Comp grind 230/236 .510/.521 112LS part # CCA-3315-3316-HR112
Originally I was ok with just 400hp Jim has assured me they have built this same set up and in house with CNC ported head it makes right at 500hp I do hand porting and have been doing so for 20 plus years so I'm no rookie at it so Jim says it for sure should make 475hp. Now that I have my 79 done with just a bored 400 I want the 78 to be meaner so I'm think of stepping up the cam and a set of ported Edelbrock heads. With a 4L80e, 3.73's and 500+hp should make for a fun ride.

oldskool

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #124 on: September 13, 2018, 10:45:37 PM »
"...researching which cam and from who get it from now..."

"...The cam...is a Comp grind 230/236 .510/.521 112LS part # CCA-3315-3316-HR112..."

https://butlerperformance.com/i-25039411-butler-comp-pontiac-custom-grind-billet-hydraulic-roller-camshaft-cca-3315-3316-hr112.html?ref=category:1272239

This Voodoo is a little cheaper.

http://www.lunatipower.com/Product.aspx?id=3210&gid=289

"....I can probably handle alittle less "street able" than most guys being it's just my hot rod..."

The next step up is a 236/242 @ .050. Butler sells one with either a 112° or 114° LSA. They say the 114 gives it a slightly smoother idle & more vac.

https://butlerperformance.com/i-29361765-butler-comp-pontiac-custom-grind-billet-hydraulic-roller-camshaft-cca-3316-3317-hr114.html?ref=category:1272239

KRE sells a similar cam, with a 112° LSA, under part number HR236.

http://www.krepower.com/Pontiac%20Cams%20and%20Parts.htm

Some seem to like more lift. For street use, I like less lift, which should put less strain on the entire valve train. But, if you want more lift, some like the OF cam, sold by SD Performance.

http://www.sdperformance.com/viewProduct.php?productID=1816

If you want a custom, Bullet can grind 'em just about any way you want it.

http://www.bulletcams.com/Masters/HRlobes.htm

« Last Edit: September 13, 2018, 11:00:02 PM by oldskool »

Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #124 on: September 13, 2018, 10:45:37 PM »

yellow1098

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #125 on: September 13, 2018, 11:21:13 PM »
Thank you....this may sound silly but I'm trying to learn exactly what the cam specs mean....lift? Duration? Alittle expiation for those would be wonderful....I know a bigger cam is needed to get to my Hp goals than what Butler suggested so I am definitely looking to step it up to maybe like the 236/242 one oldskool....I just don't know what those numbers stand for....

oldskool

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #126 on: September 14, 2018, 08:11:44 AM »
Thank you....this may sound silly but I'm trying to learn exactly what the cam specs mean....lift? Duration? Alittle expiation for those would be wonderful....I know a bigger cam is needed to get to my Hp goals than what Butler suggested so I am definitely looking to step it up to maybe like the 236/242 one oldskool....I just don't know what those numbers stand for....

The cam specs are all the cam numbers, such as advertised duration, duration @ .050" lift, max lobe lift, Lobe Seperation Angle (LSA), & overlap.

(1) adv duration is the number of degrees, of a circle, from the time a cam lobe begins to open the valve to the time the lobe closes the valve. Cam companies sometimes use different amounts of lift to measure for adv duration. For example: one company might begin the measurement when the cam lobe has opened, or lifted, the valve .004"off its seat, & end the measurement when the valve lacks .004" from being completely closed. Another cam company might measure it beginning at .006" lift & ending at .006" lift. These 2 methods would give 2 slightly different numbers for advertised duration for the same cam.

(2) duration @ .050" lift is just what it implies. It's how many degrees are required from the point where the lobe has lifted the valve .050" off it's seat, to the point where the valve is .050" from being closed, returning to it's seat. All cam companies will have to take this measurement the same. .050" lift is .050" lift, no matter who measures it. That's why most consider the duration @ .050" lift numbers the most important number to consider when selecting a cam. But, the adv duration can also be important. The "steep ramp" cams use less adv dur, in relationship to the @ .050 lift dur, in order to increase cyl pressure. These cams can really help low compression engines.

(3) Max lobe lift is distance the cam lobe will raise the lifter. To get the valve lift number, you multiply the lobe lift times your rocker arm ratio. For example: If the lobe lift is .300", & you have 1.5:1 ratio rockers, the valve lift is .300 x 1.5, which equals .450. So, you'd say that lobe produces .450 valve lift. Most Pontiac cams specs assume 1.5 ratio rockers. But not all. Since the 041 RAIV cam used 1.65 rockers, some listings for an 041 clone cam will show the valve lift using 1.65 rockers.

(4) LSA is the distance in degrees between the intake lobe centerline & the exhaust lobe centerline. Some race only cams will have a low LSA, like 106° or 108°. Most street cams will have a higher LSA, usually from 110° to 114°. It is said by most that a 114° LSA will provide a slightly smoother idle & more vac. This can be especially helpful if your cam is just slightly bigger than you need. 

https://www.classiccarrestorationclub.com/article/camshaft-lobe-separation-angle-what-does-it-mean/

(5) Overlap is the distance in degrees during which both the intake & exhaust valves of the same cylinder are slightly open. Cams designed for higher RPM use will have more overlap. This is why high rpm racing cams have a nasty sounding idle, and most require more than 1000 rpm in order to idle at all.

Well hey, these articles explain it much better & more accurately than me.

http://www.lunatipower.com/Tech/Cams/CamSpecTerms.aspx

http://www.compcams.com/Pages/416/valve-timing-tutorial.aspx
« Last Edit: September 14, 2018, 08:45:36 AM by oldskool »

yellow1098

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #127 on: September 14, 2018, 02:40:42 PM »
That is wonderful information and explains everything well......the reason I am trying to understand those specs is.... and tell me if I'm wrong....with the 461 and flat top pistons... the cam and intake selection with the heads I have will make the difference in getting me over my hp and torque goal correct?

Bluebandit

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #128 on: September 14, 2018, 03:29:31 PM »
Yes that's correct, especially the cam choice. Pick the wrong one and no matter how good an engine you have it'll run like a turd.
Don't be afraid to call the cam company's and speak with there techs. They can recommend a cam that fits your needs along with matching springs.

tajoe

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #129 on: September 14, 2018, 04:56:35 PM »
In the "good old days", Pontiacs performed best with a dual pattern cam. With now-a-days aftermarket aluminium heads, I don't know if that's the case. (?)
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79T/Aman

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #130 on: September 14, 2018, 05:46:32 PM »
modern heads are not the only factor in single VS dual pattern cam selection.
The engine is an air pump but changing the bore and stroke changes the pumping action even if the CID is the same.
For example a 455 needs more intake than a 400 even though their bores are almost the same the stroke is different and in turn affect piston speed, rod length (rod to stroke ratio) affects this more so in Pontiacs because the rods are all the same length regardless of stroke.
a 455 has a shorter draw time on the intake but draws harder so a good flowing intake is needed the longer the stroke is for a given rod length.
A short stroke has a longer intake draw giving more time to fill the cylinder.
another reason why short strokes do better at high rpm because the draw event is longer it makes up for the increased number of events in a given amount of time.
A long stroke engine  needs big ports and big cams to move as much air as possible in a shorter period of time.
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oldskool

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #131 on: September 14, 2018, 06:33:50 PM »
"...Don't be afraid to call the cam company's and speak with there techs..."


Not a bad idea to get several opinions. BUT, I'd tend to go with something closer to what Pontiac engine builders recommend, rather than what a cam company employee says. Longtime Pontiac engine builders have usually seen what different cams will do on the dyno, the street, & the strip, in Pontiac engines.
« Last Edit: September 14, 2018, 06:35:59 PM by oldskool »

Bluebandit

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #132 on: September 14, 2018, 06:57:32 PM »
"...Don't be afraid to call the cam company's and speak with there techs..."


Not a bad idea to get several opinions. BUT, I'd tend to go with something closer to what Pontiac engine builders recommend, rather than what a cam company employee says. Longtime Pontiac engine builders have usually seen what different cams will do on the dyno, the street, & the strip, in Pontiac engines.

Yes you are correct and I should have said that also. Butler, Kaufman and others that specialize in Pontiacs know what makes them run. Also Cilff Ruggles has done some amazing stuff and posts frequently on the Performance Years site.

Dave brings up a good point too, you are moving more air with 455+ ci and it requires bigger ports and more cam duration to fill those cylinders, what works in a 400 can choke a 455 preventing it from reaching its full potential.

Keep in mind its all a balancing game and all parts much be matched and work together to achieve your hp goal. Trans choice and rear gearing play into this also and must be accounted for.

tajoe

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #133 on: September 14, 2018, 08:47:21 PM »
The reason for the dual pattern cam, (so I was under the impression) was the  (iron head) exhaust port is so restrictive compared to the intake. Didn't matter about the cubic inch or bore/stroke ratio, or any other parameters, it was the unbalance of the two. When Valley head service use-ta rework RAIV heads, they opened up the exhaust port to such a degree, they said a single pattern (chevy grind) would work better than a dual pattern cam. Are the exhaust flow numbers on the Edelbrock/Kaufman aluminium heads that much better of a ratio, compared to the iron heads? Just wondering what the modern Pontiac engine builders are finding on the dynos these days.
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yellow1098

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #134 on: September 14, 2018, 11:03:11 PM »
That is exactly what I'm be confused oldskool...the custom cams vs the butler suggested ones....being the one they suggested in my original post seems to be a bit small. I was asking for better options...I think they think I'm trying to more daily drive and only need that 420 hp....when what I want out of the engine is over 500

Bluebandit...the question is what is that balance for the 461? Or would it be for the 400 block I'm starting with?

Finding those Dyno answers would be wonderful...maybe if I ask more to the point questions to Butler it will help...I think they have gotten so big though they tend to give the cookie cutter employee answers sometimes...if that makes sense

Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #134 on: September 14, 2018, 11:03:11 PM »



nas t eh

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #135 on: September 15, 2018, 02:54:26 AM »
Are the exhaust flow numbers on the Edelbrock/Kaufman aluminium heads that much better of a ratio, compared to the iron heads? Just wondering what the modern Pontiac engine builders are finding on the dynos these days.

I watched this topic get dissected on PY. Then I looked at the flow numbers on my Butler ported e-head dports and found that my exhaust flow numbers were above the desired ratio compared to the intake flow. So I asked a question over there wondering if my split pattern cam was split in the wrong direction and either needed to be single pattern or have more duration on the intake. The answer from the guys that I think I trust the most, was that the dyno usually still showed that a typical split pattern cam worked very well on ported aluminum headed Pontiacs. No need to go single pattern or reverse pattern even with the high flow exhaust numbers.
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tajoe

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #136 on: September 15, 2018, 09:07:43 AM »
Thanks for that info Nasty. It's what I was curious about. I guess like 79T/A mentioned, more to it than port flow ratio.
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oldskool

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #137 on: September 15, 2018, 10:06:17 AM »
Yeah, as many have said, it's a balancing act. How much bottom end & idle quality are you willing to give up, in order to increase higher rpm horsepower.

Basically a cam can make peak power in the lower rpm range, mid range, or upper range, BUT NOT ALL 3 at the same time.

As you can read on the Butler site, going with a 114° LSA will provide a wider power range. I, and many others, have done this with the famous 041 HFT cam, by using the bleed down Rhoads lifters.

So, this Butler cam MAY be hard to beat, as a compromise between street manners & horsepower.

https://butlerperformance.com/i-29361765-butler-comp-pontiac-custom-grind-billet-hydraulic-roller-camshaft-cca-3316-3317-hr114.html?ref=category:1272239

The weakest stroker motor shown on the KRE site has 500hp. So, it might be a good idea to ask which cam is used for each power level shown.

http://www.krepower.com/Pontiac%20Street%20Engines.htm

As for using a single pattern cam, it seems to me that if those were better for most Pontiac engines, Butler & some of the other big name Pontiac shops would recommend them. Seems that most all cams they advertise are dual pattern, with at least 6° more exhaust duration. And they do lots of head porting.

 
« Last Edit: September 15, 2018, 10:17:52 AM by oldskool »

oldskool

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #138 on: September 15, 2018, 10:35:36 AM »
"...That is exactly what I'm be confused oldskool...the custom cams vs the butler suggested ones....being the one they suggested in my original post seems to be a bit small. I was asking for better options...I think they think I'm trying to more daily drive and only need that 420 hp....when what I want out of the engine is over 500..."


Well, maybe we should explore the custom cam possibilities. If you don't think the 236/242 @ .050 cam is big enuff, exactly how big would you wanna try ? How about 240/246. Lets see if we can find some of those lobes from the list of Bullet lobes.

Yep, there are more than 30 240° lobes & more than a dozen 246° lobes.

http://www.bulletcams.com/Masters/HRlobes.htm

Looks like those 240 lobes are available with an advertised duration of from 289° up to 307°, & with different amounts of lift. They'll grind it with any LSA you want. From what Butler has posted, I suggest 114° LSA.

Then, at 242/248 is this 600hp Butler cam. Don't think you'll need a cam this big to make 500hp. But, it's your call.

https://butlerperformance.com/i-29362559-butler-comp-pontiac-custom-grind-billet-hydraulic-roller-camshaft-cca-3317-3318-hr114.html?ref=category:1272239

Then there's this bad boy, from SD Performance.

http://www.sdperformance.com/viewProduct.php?productID=1817
« Last Edit: September 15, 2018, 11:32:34 AM by oldskool »

yellow1098

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #139 on: September 17, 2018, 10:39:52 PM »
"The weakest stroker motor shown on the KRE site has 500hp. So, it might be a good idea to ask which cam is used for each power level shown"

I definitely need to give them a call and ask what they think......

I'm definitely going to look into the 240/246 and ask them at butler about its plus and minus....

Thank you so much oldskool and everyone this info is so valuable

oldskool

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #140 on: September 18, 2018, 07:37:14 AM »
"...I'm definitely going to look into the 240/246 and ask them at butler about its plus and minus..."


The 240/246 are numbers I came up with, as a possible CUSTOM ground cam. I linked the Bullet master lobes list. Butler can order CUSTOM cams, from Comp Cams. They show lobes in 6° increments, beginning with 224° @ .050. But, they mention that they can custom order other lobes. So, if you wanted a 240/246, rather than the 242/248 which they show as their 600hp cam, but had rather buy from Butler, rather than Bullet, I feel sure that Butler could order one for you.

https://butlerperformance.com/i-24623512-comp-cams-custom-hydraulic-roller-camshaft-cca-51-000-11.html?ref=category:1272239

I figure they will try to talk you into their 236/242 grind, instead of having to custom order a 240/246. But, I really don't know, for sure.

I don't think 2° would make that much difference. But, 6° should make a noticeable difference. 
« Last Edit: September 18, 2018, 07:41:50 AM by oldskool »

EspriTA350

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #141 on: September 19, 2018, 07:54:36 PM »
"...I have a spare 350 that I want to rebuild myself sometime in the future..."

Lookin forward to getting in on that discussion. I've done quite a bit of 350 build research & have taken part in several 350 build threads. Have also had some street & race 350's. Most badmouth the Pontiac 350 & tell the OP to go with a 400, 428 or 455 block. But, 325 to 500 streetable hp is possible, using a 350 block.

There are lots of cheap 350 blocks out there. Some have even junked 'em, because they couldn't sell. That's a shame, since they can be used to make decent power.

In fact, if there is any interest, I'd like to start a 350 block ONLY build thread, where we can discuss the options available for different levels of performance. So, all who'd like to see and/or be involved in such a thread, please say so here.

There may have already been some 350 threads here. Don't know. But I, along with probably many others, prefer a fresh discussion, with all the latest info, rather than just searching for an old thread.

I'm very interested in a 350 thread. Was wondering myself why there was one for every motor but that.

737driver

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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #142 on: September 20, 2018, 05:46:34 AM »
I think a 350 thread would be a great idea. I think they have very good  potential as a performance motor. Ideally I think they would be a great replacement engine for the later 2nd Gen Firebirds with the V6 or 301 motors (or the ones with Chevy engines ). Both 350 engines I have run exceptionally well. Also I see more of them for sale/ available than the 400 or 455.
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Re: Pontiac stroker advice for 500hp...stroke size,cam,intake,heads?
« Reply #142 on: September 20, 2018, 05:46:34 AM »
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