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Old 03-14-2021, 05:31 PM
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Could be of interest, one of Paul's comments on the subject of a 110 LSA.....

"Let me make one thing perfectly clear. When I talk about narrower lobe sep cams in big engines, I am specifically talking about Harold cams. Not Comp XE or anyone else's tight LSA cams. Harold did many things differently to his lobes. Things NO ONE ELSE DID! These subtle little things created lobes that when ground on a 110 LSA, gave the power band performance of a cam ground on a 112-114 LSA. Just look at some of the Voodoo lobes."
Paul Carter


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Old 03-14-2021, 05:54 PM
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Quote:
Originally Posted by Gary H View Post
That's a pretty choppy cam if ground on a 110 LSA. Not saying it won't work, at all, but be prepared for a pretty rough idle.
That's what most would think by looking at the specs on paper, but according to Paul Carter, the Voodoo cams seem to have manners that make them act smaller than one would think. I guess it is the way Harold designed the lobes. Here is a video of the 704 cam in a 462 pontiac, although it doesnt state what compression it has, it sounds relatively mild for its specs, but has just enough attitude to sound great for a street car.

https://youtu.be/oPlC13g4BCo

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Old 03-14-2021, 06:11 PM
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That's what most would think by looking at the specs on paper, but according to Paul Carter, the Voodoo cams seem to have manners that make them act smaller than one would think. I guess it is the way Harold designed the lobes. Here is a video of the 704 cam in a 462 pontiac, although it doesnt state what compression it has, it sounds relatively mild for its specs, but has just enough attitude to sound great for a street car.

https://youtu.be/oPlC13g4BCo
I just wanted to be clear about the link I just provided above... I reach out to the owner, and he told me his 704 is indeed on a 112° seperation, instead of the normal 110°. His engine also had 9.6-1 compression. So the normal 110° 704 would have a little more attitude than the one in that video, but I still think it would be fine for a 9.6-1 to 9.8-1 467 cu in engine.

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Old 03-14-2021, 07:15 PM
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Just a suggestion here!

As the world spins there may come a time down the road when more lift may want to be run .
The limit to this will be the installed height.

You can get this potential limit out of the way now by having the spring seats cut ,060” and just run a .060” hardened shim for now.
Doing this will allow you to not have to pull the heads if that day comes when the valve lift gets increased and taller springs are needed, and yes there is plenty of meat in the heads to have a cut of .060” done to the spring seats.

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Old 03-14-2021, 11:47 PM
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To me a 704 in a 4.25” combo’s have a decent lope to them, like Garry H mentioned. Not sure I can tell the idle apart between a 704 in a 455 or a 703 in a 400. But, you might miss the some bottom end on the 400, the bigger cubes should have that covered.


Bullet has almost the identical profiles, same intensities with different lifts. The 280,288 232,240 @.050versus 281,289 233,241 .050 on that Lunati. IRC I did a 283,291 235, 243 Bullet also, it is the next step up from the 280 profile. We have used some bigger ones to from that family also, great profiles IMO. Aggressive but not as extreme as a comp XE. Usually I widen the LSA out to 112 or 114 with Exh manifolds, 110 with headers. Smaller stroke I have done 110 with manifolds though. Lunati cost a little less to do the custom lsa, but with shipping it isn’t much different. So I have done more from Bullet than Lunati.

We have always done 4 to 6 on the advance like Harold suggests.

They seem to be very effective at filling cylinders, seems like they are forgiving with less compression than other grinds. The last 462 we was closer to 9.0 than 10 compression. It was on a 112 LSA and a 108 ICL and sounds just like your video link. It was a 232,240 Bullet with 1.65 rockers with .550 lift.

I went with the 4.25” stroker in my W72 4 speed 3.23 T/A.


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Old 03-15-2021, 12:25 AM
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Quote:
Originally Posted by Jay S View Post
To me a 704 in a 4.25” combo’s have a decent lope to them, like Garry H mentioned. Not sure I can tell the idle apart between a 704 in a 455 or a 703 in a 400. But, you might miss the some bottom end on the 400, the bigger cubes should have that covered.


Bullet has almost the identical profiles, same intensities with different lifts. The 280,288 232,240 @.050versus 281,289 233,241 .050 on that Lunati. IRC I did a 283,291 235, 243 Bullet also, it is the next step up from the 280 profile. We have used some bigger ones to from that family also, great profiles IMO. Aggressive but not as extreme as a comp XE. Usually I widen the LSA out to 112 or 114 with Exh manifolds, 110 with headers. Smaller stroke I have done 110 with manifolds though. Lunati cost a little less to do the custom lsa, but with shipping it isn’t much different. So I have done more from Bullet than Lunati.

We have always done 4 to 6 on the advance like Harold suggests.

They seem to be very effective at filling cylinders, seems like they are forgiving with less compression than other grinds. The last 462 we was closer to 9.0 than 10 compression. It was on a 112 LSA and a 108 ICL and sounds just like your video link. It was a 232,240 Bullet with 1.65 rockers with .550 lift.

I went with the 4.25” stroker in my W72 4 speed 3.23 T/A.
Thanks Jay, since this car is a daily driver and has A/C, maybe it would be better to look at doing something like the 703 for this build, or maybe the 704 on a 112 seperation. We were just looking to run a big enough camshaft to avoid any potential detonation problems, but also don't want a cam that is going to be over the top choppy either, but wouldn't mind a little attitude at idle. That is something we will have to decide on

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Old 03-15-2021, 01:05 AM
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I would probably do the 112 version of the 704 before the 703 in a 455, especially if the compression is past the mid 9s. Power wise I think it would be down a little from the 110 lsa 704 version with the headers, but on the 112 it would be a friendlier pump gas driver combo for sure.

704 at 110 would not bother me with a/c. Just because it would not bother me though, does not mean it is ok for someone else. I have bigger cams than that with A\C. But, I like the choppy idle though. The 280/288 Bullet with the 112 lsa is in a friends 455 gto, auto with 2500 stall and 3.07s with A\C. My W72 T/A is a 245/253 HR with a 114 lsa with A\C. My biggest cam with A/C is a 255/263 112 lsa SFT, 542 cid though. Not like they are 4 bangers engines that pull down when the a/c kicks on.


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Old 03-15-2021, 10:48 AM
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I have ran the Crower 60919 RA IV style cam in a 455 years ago, and it didnt even have much compression, probably below 8.5-1 as far as I remember, but it ran decent, and the idle wasn't too bad. This engine will have quite a bit more compression to soak some of the cam up compared to that one. How would the normal 110° seperation VooDoo 704 idle manners compare to the 60919? The 704 has quite a bit less overlap than the 60919 I believe doesn't it?

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Old 03-15-2021, 11:11 AM
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That 60919 cam in a 455 is actually not bad at all. It's out on a 113 LSA if I remember correctly, and even with stock (non bleed) lifters it still idles well enough and makes vacuum, if compression is somewhat decent.

Here is a custom 239/243 done with Voodoo lobes that Paul Carter spec'd, it's a hydraulic roller with over .600 lift but the idea is similar. He ground this on a 112 and I installed it at 106.25 ICL per his recommendations. This car has AC and 3.42's, and is making 12 inches vacuum up at 5000 feet elevation. It's 9.98:1 compression with iron heads and runs great on 91 pump gas.

The voodoo lobes seem to idle a little more tame than other cams I've used with similar duration and LSA. As you can hear, once it's warm and settles into a nice idle, it's only a noticeable lope. Nothing radical at all. I have other videos driving it around, it drives like a stock firebird, works the power brakes just fine, and just sits here and idles at 800 rpm easily. Kick the idle up a pinch more and it's even smoother. Using a Voodoo 704 with just 233 @ .050, 6 degrees less than this cam, even on a 110 I would suspect shouldn't idle any more choppy than this cam once tuned and dialed in properly.

https://youtu.be/AOqwz3QlO5k

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Old 03-15-2021, 11:21 AM
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The Ultradyne 288/296 on a 108 ran my A/C, PB fine in the '78 on my first 455 and a 400. The 296/304 on a 112 is a little lopey in my current 455 in the 78.

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Old 03-15-2021, 12:11 PM
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Quote:
Originally Posted by Formulajones View Post
That 60919 cam in a 455 is actually not bad at all. It's out on a 113 LSA if I remember correctly, and even with stock (non bleed) lifters it still idles well enough and makes vacuum, if compression is somewhat decent.

Here is a custom 239/243 done with Voodoo lobes that Paul Carter spec'd, it's a hydraulic roller with over .600 lift but the idea is similar. He ground this on a 112 and I installed it at 106.25 ICL per his recommendations. This car has AC and 3.42's, and is making 12 inches vacuum up at 5000 feet elevation. It's 9.98:1 compression with iron heads and runs great on 91 pump gas.

The voodoo lobes seem to idle a little more tame than other cams I've used with similar duration and LSA. As you can hear, once it's warm and settles into a nice idle, it's only a noticeable lope. Nothing radical at all. I have other videos driving it around, it drives like a stock firebird, works the power brakes just fine, and just sits here and idles at 800 rpm easily. Kick the idle up a pinch more and it's even smoother. Using a Voodoo 704 with just 233 @ .050, 6 degrees less than this cam, even on a 110 I would suspect shouldn't idle any more choppy than this cam once tuned and dialed in properly.

https://youtu.be/AOqwz3QlO5k
Thank You sir, beautiful car, and sounds really good... With this car being a 4-speed manual transmission, I'm thinking it won't be quite as fussy as an automatic either. We would like it to make around 13" of vacuum atleast, we are at 1100ft elevation.... I wonder how much vacuum the Voodoo 704 on a 110 seperation would make in a 9.7-1 compression 467 at 800 RPM idle?

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Old 03-15-2021, 12:21 PM
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13" shouldn't be a problem with that 704 cam when near sea level in a 455 with some compression.
I typically see an increase of 3-4 inches of vacuum when I drive down to sea level.

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Old 03-15-2021, 12:23 PM
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That engine by the way is actually a 467
like yours with about the same compression you're looking to do.

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Old 03-15-2021, 04:23 PM
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The last 60919 I did was a pretty aggressive profile (285/294 at .006), and I am confident it would idle a little better than a Lunati 704 on 110... but I can not totally say for sure. Lol....becuase I had another 60919 that had 308* at .006 tappet on ALL the exhaust lobes. I assume there may be more 60919s like that one out in circulation. That bigger profile is one I would want Rhoads on it, the next one didn’t need them and we run them tightened down so the Rhoad’s don’t do much of anything.

I think the current 60919 is a little different than it was in the past. Where it was 113 LSA and a 109 ICL and more seat timing I believe it is currently set on a 112 LSA with a 108 ICl. The 60919 seem like it has more aggressive ramps now also, or maybe it doesn’t ....The 60919s last couple years the cam card said 112 LSA and 109 ICL. Steve C posted a link to the cam card not to long ago and it had 112 LSA and a 108 ICl, so it appears it had another change, at least on paper. The current cam card also had some wacky 150 lbs seat pressure and 350 nose pressure requirement. That last cam card change was it for me. My luck I want the long seat timing to help manage compression some and I get the aggressive one, or try to use it in a 400 thinking it is the aggressive version and it is the lazy version. Lol

704 on a 110 has 65.5* of overlap at .006” tappet and still has 17* by .050 tappet.
The last 60919 I had thru here had 67* at .006” tappet and has 11.5* at .050.

The 704 is roughly 4* longer on the closing side than the opening side on both intake and exhaust from .050” to .006” tappet. That changes the looks of the cam card seat events a fair amount. The 17* is a good amount of overlap at .050”, gives it the rougher idle.


Last edited by Jay S; 03-15-2021 at 04:59 PM. Reason: Err
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Old 03-15-2021, 05:44 PM
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Quote:
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The last 60919 I did was a pretty aggressive profile (285/294 at .006), and I am confident it would idle a little better than a Lunati 704 on 110... but I can not totally say for sure. Lol....becuase I had another 60919 that had 308* at .006 tappet on ALL the exhaust lobes. I assume there may be more 60919s like that one out in circulation. That bigger profile is one I would want Rhoads on it, the next one didn’t need them and we run them tightened down so the Rhoad’s don’t do much of anything.

I think the current 60919 is a little different than it was in the past. Where it was 113 LSA and a 109 ICL and more seat timing I believe it is currently set on a 112 LSA with a 108 ICl. The 60919 seem like it has more aggressive ramps now also, or maybe it doesn’t ....The 60919s last couple years the cam card said 112 LSA and 109 ICL. Steve C posted a link to the cam card not to long ago and it had 112 LSA and a 108 ICl, so it appears it had another change, at least on paper. The current cam card also had some wacky 150 lbs seat pressure and 350 nose pressure requirement. That last cam card change was it for me. My luck I want the long seat timing to help manage compression some and I get the aggressive one, or try to use it in a 400 thinking it is the aggressive version and it is the lazy version. Lol

704 on a 110 has 65.5* of overlap at .006” tappet and still has 17* by .050 tappet.
The last 60919 I had thru here had 67* at .006” tappet and has 11.5* at .050.

The 704 is roughly 4* longer on the closing side than the opening side on both intake and exhaust from .050” to .006” tappet. That changes the looks of the cam card seat events a fair amount. The 17* is a good amount of overlap at .050”, gives it the rougher idle.
Wow, lots of great info, thanks! I'm starting to maybe lean a little towards the 704 on a 112 seperation for this engine, but then you read stuff from Paul Carter saying that in a 455-467 engine, the 704 doesn't need the 112 Seperation, due to the lobe design and offset, unless you want to make power over 6000 rpm, which is not the case here. I even read a post from him saying that he installed the 704 for a couple in their 70's, because the previous camshaft was to big for their likeing, and they loved the result of the 704 in their 455, so that leads one to believe that it must not have too bad manners. It takes alot of thought and reading to decide on a camshaft for a particular application, but its alot of fun reading for sure!! Lol

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Old 03-15-2021, 07:12 PM
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I like threads like this. Great information and a really good read.

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Old 03-15-2021, 08:58 PM
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Subject touched upon here and might be of interest....


Both Harvey and I design Unsymmetrical cams, where the opening side and the closing side are different everywhere except at the nose, where we match both sides through the 3rd derivative, at least. We both use different off-sets, the difference between the opening and closing sides, even at .050".
My old 288R that I designed in April, 1980, thought it was a 282 at .020 when it opened, a 252 at .050. Then it knew it was a 258 at .050 when it closed, and 294 at .020, still closing. The 288R was notorious for bottom-end torque, and good power everywhere. It had 176 at .200, one degree more than the Crane R260/4167.
What I use now is the R255416H. This rascal thinks it is a 279 at .020 when it opens, still a 252 at .050, still a 258 when closing, and now a 288 at .020. At .200, 180 degrees. I've lost 5 degrees at .020, kept the same duration at .050, and gained 4 at.200. It has gained power everywhere.
Remember, it is not WHAT the duration is, but WHERE the duration is, that counts in camshafts. Remember, the engine sees WHERE the duration occurs, not WHAT the duration is.
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Old 03-15-2021, 10:22 PM
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Ok, so earlier, up above in this thread, I posted a youtube link to a car with a 462 Pontiac and the 704 voodoo camshaft. I later stated that I had talked to the owner of that car and he confirmed that he was running the 704 on a 112 seperation, instead of the normal 110°. After doing much more research, I have now found out he is a member here, and goes by "ponchjoe", and found a post from back in 2018 where he had just finished installing that 704 camshaft, and provided the very same link that I had posts above. He states at that time, that his 704 has the 110° seperation, not a big deal at all, but that changes my outlook on the 704 on a 112 seperation thinking, because I think his car sounds great, without being over the top for a street car, so now I'm pretty well set on the normal 704 VooDoo on the 110° seperation. Here is the quote from where he was talking about it back then...

Quote:
Originally Posted by ponchjoe View Post
I thought I would share the sound clip to my 462 with the Voodoo 704 on a 110. There’s a lot of cam recomendation threads here so I thought the sound clip would be a welcome addition. The 2.5 exhaust is RA manifolds with a Pypes X and Race Pros.

https://youtu.be/oPlC13g4BCo

Thanks to Paul (gtofreek) for the recommendation and Paul K for the Hylift Johnson’s

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Old 03-16-2021, 12:40 AM
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Really like this discussion. Recently had a ’73 with a 496 finished. Usually, I would go with a cam @ 110 with headers. Decided to go with 112 with headers. Wanted a little more vacuum for the power brakes. I was worried the size of the engine would really smooth out the idle too much. I was pleasantly surprised. Cam is a comp cam 242/248 @.500 112 LSA.

https://youtu.be/WzZHKujbmLI

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Old 03-16-2021, 07:16 AM
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Some comments on the Crower 60919 camshaft and selecting a cam for a 455 in general.

Dating clear back to 1999 all the 60919 cams I've installed here were 304/316, 231/240 @ .050" and on a 113LSA, ICL at 109.

The last one we used was about 7-8 years ago and it was this version.

All that time the Crower website clearly stated that the cam was 112LSA with the ICL at 108.

ALL of the 60919 cams I installed came in much closer to 112-113ICL and had to be advanced to get them to 109ICL as stated on the cam card. I truly believe to this day that Crower was either re-boxing SPC-8 cams or grinding them at or very close to the original RAIV specifications.

They may have started actually grinding them to the specs shown on their website recently. I personally haven't seen this version but haven't used a flat cam in quite a while in one of these engines. If you go to their website right now the cam card still states 304/316, 231/240 and 112LSA.

That's what it has always stated nearly as I can remember but the cam they are currently selling may be what Jay describes above.

Anyhow, I've been around 455 Pontiac street engines for a good many years now. They are a HUGE engine and require a pretty hefty cam if you want to make great power from them. They also love larger cams on wider LSA's. Doesn't mean you have to go that direction but for sure you can smooth out the idle, improve throttle response, clean up stinky exhaust and make great power with a big cam on a wide LSA. You do NOT need a lot of compression either, but it is always your friend with these things as high static compression ratios offset negatives from more overlap and longer duration.

Some cam companies will tell you flat out that LSA doesn't matter. Not going to argue LSA but keep in mind that tighter LSA INCREASES overlap all else being equal, and in almost all cases those cams are ground for advanced ICL and earlier intake closing. One needs to realize here that both of those moves INCREASE cylinder pressure, narrow up power, and spike dynamic compression higher (and earlier) as the engine revs thru the power range. At the same time this INCREASES octane requirements. So one can very quickly get into trouble trying to manage pump gas with a 455 build even if you have lowered the static compression ratio.

Below is a CLASSIC example of how this works. I've put it up here many times but it is a great example and we can learn from it. Here is the entire story.

Customer calls me up, he owns a speed shop, builds engines, ports heads/uses a flow bench for a living and owns a dyno. He is doing his first Pontiac build, but has vast experience with 460 Fords (and stroker variants) and Big Block Chevy engines. He is stroking a 400 and has custom ported a set of #96 heads for it to 250cfm. He is going to use a later model Q-jet on an RPM intake. He asks me to spec out a custom rebuild kit with tuning parts for the Q-jet he is going to use on this engine. At that time he hasn't nailed down a cam selection but tells me it will me a moderate size hydraulic roller cam.

The next phone call I get is dyno day for the engine and he tells me the engine is on the dyno, ran-in, and they were trying to make pulls but ran into detonation issues and power production is WAY less than expected. The static compression is only 9.3 to 1 so he isn't understanding it. Of course everyone right down to the guy taking out the trash is blaming the Q-jet. So I dodged all the questions about the carb being too small, fuel bowl too small, etc, etc. Instead I asked about the cam choice and he tells me he ended up with a Comp XR-276HR cam, recommended by the tech at Comp Cams. I told him that he should remove the cam and install a larger cam on a wider LSA. Instead he removes the Q-jet, installs his "dyno mule" Holley 850DP carb and commences to add timing to make better numbers and immediately blows up the engine. He ended up pinging it so hard that it spun most of the rod bearings!

So I get another call and he asks me for a cam recommendation. I spec out an Old Faithful clone with the older Magnum lobes on a 114LSA and tell him to put the ICL at 110. A little bit of silence then he says OK.

Couple of weeks later I get another phone call. He also sends me a dyno sheet from both cams. They are shown below. During the conversation he also mentioned that he put the Q-jet back on the engine (he had sent it here for me to check out and "tweak" if/as needed) and it was flawless. He also mentioned that the engine idled smoother with the larger cam in it and the "quirky" shake at idle was gone. He also noticed that it was more responsive to quick throttle movements and that he was able to throw more timing at it without any detonation.

That is the short version of the long story with more details than I've put up here before and below are the overlaid dyno charts from the XR276HR cam and the Old Faithful clone out on a 114LSA.

Morel of the story here is to realize a couple of things. A 455 engine is a HUGE engine. They have a long stroke and cylinder heads with no more cross section than an average Small Block Chevy performance head. They need a LOT of cam to make great power. With it's great piston speed they are sensitive to the intake closing point plus exhaust scavenging. For all the naysayers on here who continue to promote tight LSA none of this means you can't go that direction. I've ran into this same scenario before tuning troubled 455 Pontiac engine builds. Small cams on tight LSA's are the WORST possible direction you can go with them. When you start using larger cams you can get them to work just fine, and about all tight LSA does is give them more "attitude" at idle and stinky exhaust. The best thing about the story above is that it was a rare occasion where only ONE change was made and I had nothing to do with any of it besides supplying carburetor parts and checking the customers work........Cliff
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https://cliffshighperformance.com/
73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile),
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