[Skippy597]

I would love a custom cam by Tim but I have spent way too many attempts at trying to reach Bullet to no avail.

It's comical because for some reason every Dyno sheet I see of a Pontiac they prefer a 112-114 lsa. This completely goes against the thought that every engine is just a air pump of slightly different design and the generic cam recs like from David vizard don't apply. I'm still learning all this and this is my first performance Pontiac build.

If anyone has a trick at getting tim on the line I'd be more than open to it.

[JLMounce]

When I rebuilt my engine last year I talked with Bullet about getting a cam made. At the time their lead was over 8 weeks. I went with a comp spec'd by Jeff Kauffman that uses the newer Q series lobes (QNI in my case) and I've been really impressed with the cam. The valvetrain is MUCH quieter than the comp XFI lobe cam I had in the engine previously.

[Dragncar]

I don't know but plenty of people have made some really good power on 455s- 461s with heads flowing less than 330cfm.
There seems to be more to it than cfm with a given ci. LS and sbc's have much lower drag and are slinging around much, mush lighter hunks of metal tha we are. Valve spring pressure can be a lot lighter too when parts do not weigh so much.
Tim, keep trying. He can be hard to get ahold of but is worth the wait.

[grivera]

Originally Posted by JLMounce

The valvetrain is MUCH quieter than the comp XFI lobe cam I had in the engine previously.

Are the XFI lobes inherently noisy? I thought your valvetrain noise was attributed to the Lunati/Morel lifters, versus the new with Johnson lifters?

[JLMounce]

Originally Posted by grivera

Are the XFI lobes inherently noisy? I thought your valvetrain noise was attributed to the Lunati/Morel lifters, versus the new with Johnson lifters?

The lobe intensity on the XFI's is pretty aggressive. They likely exacerbated the noise issues that was inherent with my Morel lifters.

If you do some searching on the XFI lobes, it's a somewhat common complaint that it produces a noisy valvetrain. The QNI lobes on my current cam, although having more lobe lift are less aggressive on and off the ramp. Comp developed this lobe profile specifically with quiet valvetrain in mind.

[grivera]

Curious how noisy the XFI lobe cam would be with the Johnson lifters. I have KRE HR242 on the shelf, which may be XFI lobes.

[JLMounce]

Depending on the age, yes it's likely that cam has XFI lobes. You should be able to cross reference the lobe from your cam card.

With a good quality lifter, I would bet that you still hear the valves clicking as they slam shut against the seats.

That cam was in my engine for about 8 years and a decent amount of miles. When Jeff went through my heads, there was no need to redo the seats. After 8 years of service the heads got Jeff's 310cfm port, new springs for the larger cam and seals.

Point being the XFI lobes may have been a bit noisy, but it wasn't causing any damage anywhere.

[Steve C.]

If it helps Tim Goolsby is, or was, at extention 102

https://www.bulletcams.com/



.

[Skip Fix]

Got my custom SR from Bullet recently in less than 2 weeks!

[lust4speed]

I'll bet that Powell saw the 3.36 rear gear along with the 2.52 low and compensated for it. Although the 230/245 spread is terribly wide and more suited for a really choked exhaust.

I like to stay at or under .600" lift on an engine that will see a lot of street miles. Maybe a little too conservative? Additional lift is pretty much free horsepower but the additional stresses start to worry me. Comments?

I believe that the Butler cam is slightly warmer that the Comp and with the little extra LSA should be just as streetable. Butler would be my first choice with Comp a very close second. I think Powell might have missed the mark on this one.

[Skippy597]

I have tried reaching out to butler again to no avail. What time of day are you guys calling Tim at to reach him?

The butler cam seems pretty interesting to me I just don't want anything too big for the street with a stick car. I feel like the 236/242 comp is a decent compromise cam and a bunch of people running them with good results. If the consensus is the butler cam on a 113 isn't too big then I like the idea of going with it.

[lust4speed]

While I have a favorite or two at Butler, all the techs are very good. If you keep ending up at voicemail when asking for Tim (who I haven't talked to), then I'd just say I have a cam question and asked to be connected to an available tech.

[ponjohn]

Originally Posted by lust4speed

I'll bet that Powell saw the 3.36 rear gear along with the 2.52 low and compensated for it. Although the 230/245 spread is terribly wide and more suited for a really choked exhaust.

I like to stay at or under .600" lift on an engine that will see a lot of street miles. Maybe a little too conservative? Additional lift is pretty much free horsepower but the additional stresses start to worry me. Comments?

I believe that the Butler cam is slightly warmer that the Comp and with the little extra LSA should be just as streetable. Butler would be my first choice with Comp a very close second. I think Powell might have missed the mark on this one.

I bet in Powells opinion the Pontiac exhaust is choked, probably compared to other cylinder heads.

[AG]

Originally Posted by Skippy597

I have tried reaching out to butler again to no avail. What time of day are you guys calling Tim at to reach him?

The butler cam seems pretty interesting to me I just don't want anything too big for the street with a stick car. I feel like the 236/242 comp is a decent compromise cam and a bunch of people running them with good results. If the consensus is the butler cam on a 113 isn't too big then I like the idea of going with it.

Last time I spoke to Tim was 2022 when I bought a HR cam from him with head flow specs, engine size etc. I think your philosophical approach to cam size is sound and for me anything between 110-114 LSA for the street is fine unless it's full race. My race SR can is on a 110 LSA. I put an OF 235/245 HR cam in my brother's 464 CI on a 112 LSA and the motor performs very well.

[Steve C.]

"I bet in Powells opinion the Pontiac exhaust is choked, probably compared to other cylinder heads."

X2

Related: NOTE the revised exhaust port design on Paul Kinippen's new Edelbrock cylinder heads.

[scott70]

Is a iron D port head that’s been ported using rare oversized iron manifolds and a 3” head pipe a good candidate for a 236/242 hr cam or would you want a little more exhaust duration?

[Skip Fix]

With good exhaust the old HO Racing guys recommended a single pattern for ported D ports!
I think the exhaust manifolds would warrant a "regular" split pattern.

[Steve C.]

A good read...

Bad exhaust ports?
https://forums.maxperformanceinc.com...d.php?t=820491

And a tidbit that might be of interest.....

A statement in that thread linked above by Cliff Ruggles...
"To be the devils advocate again there is a LOT more to this port flow deal than can be measured on a flow bench."
He goes on to elaborate, but that statement rang a bell.

I know they are not apples-to-apples with factory d-ports in this thread, but in my recent conversation with Paul Knippen regarding his revised Edelbrock exhaust port he mentioned a similar situation as Cliff brings up.
How his exhaust ports "behaved" on the flow bench, and not related to the numbers obtained.

Memories, my old engine builder years ago used to "listen" to his flow bench.

.

[Skippy597]

That was a good thread to read.

I still feel the round port after market heads definitely have sufficient int to ex ratio.

I'm leaning pretty heavy towards to butler custom grind 239/247 113lsa. Does anyone think I'll have issues with power brakes and a/c.?

[Jay S]

Originally Posted by Skippy597

That was a good thread to read.

I still feel the round port after market heads definitely have sufficient int to ex ratio.

I'm leaning pretty heavy towards to butler custom grind 239/247 113lsa. Does anyone think I'll have issues with power brakes and a/c.?

Unless has something different than the stock booster I think power brakes would be a little sketchy in an early A body with Bulter’s cam. Would work ok with a gen 2 F body power brake set up or possible a different booster than stock on the early A. I am assume this is going in a 66 A body?