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Discussion Starter #1
What would the process be for making a pontiac 455 into a roller engine?

1. Roller cam
2. Roller rockers
3. Roller lifters.
4. Shorter pushrods

I was hearing that the block needs to have some type of conversion? Is that true :confused: from aside what I stated above? This would be project of mine in the future when tax return time come around, just needed some feed back.
 

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You got it. The stock valley pan won't accept current roller lifters without modification.
Of course lots of poncho parts places sell aluminum pans that clear the roller asemblies and aren't all that expensive. I seem to recall the $35 neighborhood and I'm contemplating one just so I can switch to a roller if I want, and I then wouldn't have to worry about the 30 year old crud in my stock pan rattling around in my fresh rebuild.

I say current roller lifter simply becuase you never know when some genious will come up with a super short alignable version of a roller lifter...or something.
 

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Discussion Starter #5
I read in some other post for a chevy 350 the lifter bores may need to be drilled is that correct for pontiacs too?
 

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Not unless you have something really wild and funky going on. A setup for a Pontiac 455 shouldn't need anything out of the ordinary. Just the roller gear you purchase- and a modified valley pan- at least that was all I saw on the rollers for Ponchos I've dealt with- though admitedly that's only 2.
 

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Well first off the Chevy lifters are too short to work correctlly in a Pontiac's valvetrain. Second you can use a stock valley pan with a roller. Also when you consider a roller you have to consider whether you want to use a hydraulic roller or solid roller. If you use the solid roller then you have to restrict the oiling to the lifters and you should consider using a brace with the solid roller. Also you want to make sure your bottom end is built well enough to handle the added cylinder pressure and enough compression for the cam you use. Also you need to have your heads ported to flow a minimum of 280 cfm on the intake side. Also you'll need better valves and at least a competition three angle valve job. Forged pistons are pretty well a must with the added cylinder pressure along with some good rods and a well prepared crank. You will also have to improve the oiling system and you have to change the gear on the distributor as the stock gear will strip. You'll also need a well prepared intake and in alot of cases an 850 cfm carb, or a highly modified 750 or 800. You also need a well thoughtout ignition system also. With either type of roller a double roller billet chain and gears are recommended. As far as pushrods you will likely have to either get them from the cam manufacturer or have them custom made and roller rockers are a must. AS far as exhaust large tube headers and 3 inch mufflers are a necessity. Also you'll need a good convertor if an automatic is to be used and gears compatable to the engines rpm potential and the cars wieght but in alot of cases either a 3.55 or 3.62 does fine in cars with larger inch engines as the torque output is greatly increased in the mid range. There's more to it than just throwing a cam in and going.
 

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Discussion Starter #8
Grusome Goat as always thx for the awesome info...I had no clue that much had to be done for a roller engine...Thats a lot of $$$$ to think about :)
 

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I'll not say most of what Grusome said is a good idea, though I completely forgot about the distributor gear that's a must so boo to me. Though I did just hear from someone the Crane has a roller setup with an iron gear so be sure to pay attention to what you're getting there.
I will argue that you probably don't need your heads to flow 280 or that you would necesarrily need better valves and a three angle valve job. Though that said it depends a lot on what heads you have and what sort of shape they're in. My bad for not asking what heads you have. You will need to change your springs I always forget about that, but anytime you change a cam you should be looking at your valve-springs. I'll also say that your 455 probably has stock rods that will work with a roller. As for the valley pan- if you have an EGR valley pan I honestly don't see that working, but I haven't seen one tried with a non-EGR pan so maybe those would work.

GrusomeG certainly put more thought into his answer, everything he said will make for a better more reliable combination, particularly for a race oriented motor but you might be able to get away with less than he's saying you will need.
 

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Claymore a freind of mine just sold a 455 with a roller and he purchased some heads from Pontiac Dude (Kens Speed and Machine in Florida) and Ken asked him about what cam he had and prepped the heads accordingly. Dude flowed the heads (4X's)to around 285 cfm on the intake so the engine would perform with this type of cam. Pontiac heads are real restrictive on the intake side and can only handle a maximum lift of around .465 on the intake side in stock form. With the increased lift and lobe design of the roller the head work is a requirement or your defeating the purpose of the design of the cam or it's intended use. These heads were heavily worked as far as milling and valves to get the compression where it was compatable with the cam and also worked the valves for increased flow. This engine was intended for a 65 GTO clone but the 65 was sold in order to get a 69 Judge and since the 65 was sold so was the engine a short while later. I myself have plans to build a stroker with a roller here in a couple of years so I have already researched alot about what work is going to need to be done. One difference is mine will be a race engine and will never see the street so a solid roller of in the area of .640 lift will be used unless i get crazy and go with a hydraulic roller and put in my GTO and run it on the street. Either way I go with my stroker it will have a roller and will have heads capable of flowing around 285-320 cfm's and are likely to be aluminum heads rather than factory iron.
 

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Grusome- For the most part 98% if you want to quantify it, I agree with you. The stock Poncho heads are restrictive and typically don't flow big CFM without a ton of work (and by that point Al heads start to look good) and while the roller wants more air and needs more air to really do its thing to its fullest you can get away with less flow. I don't think it completely defeats the purpose of the roller setup just deminishes and/or minimizes the potential gains you would get from it. Sometimes to the point where it would be a waste of time and money, I'll admit.

I have a lot of respect for what you are saying as you put a lot more thought into your post than I did mine; I just think there is still some good to be had from a roller even if you don't have everything else optimized to go along with it- it just makes more sense to do so.

Oh and Grusome- put it on the street, we can never have too many radical ponchos on the street :thumbup:
 

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Well for the last 18 years I have raced only Pontiacs ( in fact the same 71 GTO) and when I started out racing in the late 70's it was in a 69 383 4 speed Road Runner and then raced Fords and Chevy's in the early to mid 80's. The reason I settled on Pontiac's is when I got my Goat I'd always wanted one. Now I live and breath Pontiacs but you may not believe this but I have a couple of guys trying to put together a 455 to take my 400 and my 400 equipped GTO is quicker than my club presidents (Carolina Classic Pontiac's) 455 equipped 71 Trans Am. Alot of trial and error has been learned over the years to get to where I'm at now. If you look under the hood of my GTO right now (sorry I don't have any pics to post) you would see what looks like a bone stock 400 with a spreadbore Holley and headers but looks are deceiving. Also I have what looks like the stock suspension under it but with 26 inch tall slicks and a 3.55 open rearend will pull the front wheels of the line. Alot of thought has been put into this car as far as performance and is facing further modifications to some of the suspension before the 412 goes in sometime next year. With a flat tappet hydraulic cam (custom grind) and either the Holley or Q-jet (intake is going to depend on what comes up on the dyno) projected times in the 1/8th should be in the 7.20 range and this is with a street car. Whenever I get around to building the stroker for a race car then I plan on low 6's and this will also be with a four speed in both cars and no nitrous on either car. Also right now the 400 is a true 400 with the factory pistons, rods and crank and the 670 heads have not been ported (yet) but do have stainless steel valves, what my machinest calls a street 3-angle valve job with Isky springs and retainers, Comp rockers and ARP studs. Nothing fancy in my setup but will tear my head off in all four gears and so far I haven't found a street tire yet that will handle this engine. This is the block I intend on using for my stroker even though I have given thought to using the short block in a 69 Pontiac Custom S that I'm getting ready to start on for my wife but with lower compression (around9-9.5:1) mild cam with 3.08 gears and Turbo 350 trans. This car will be mainly a driver for her but will still rip off high to mid 8 second times in the 1/8th with me driving through the mufflers. This would equal out to mid to low 13 second times in the quarter and that is nothing to sneeze at.
 

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GrusomeGoat all I can say is "I'm Jealous" It's nice to hear some great Pontiac passion! I have been in Pontiacs for over 35 years. Everything you mentioned in your post is correct and mostly directed towards a Drag car. A nice street cruiser could benefit from a hyd. roller cam. Just the roller cam set up efficiency verses the flat tappet set up produces HP gains. I have mentioned on other posts the .475 ceiling on valve lift for stock Pontiac heads. Several responders challenged that theory. Its nice to have someone agree with me! Anyway... there plenty of Hydraulic roller cams out there with less than .500 lift that would wake up his Indian.
 

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Granprix76..Doug Herbert offers a nice .480 lift 230 @.050 duration hydraulic roller cam that would work great in your 455 for about $249. It would have a little lope at idle but you may not require a stall converter. I recommend the aftermarket valley pan with a roller cam. Those retrofit lifters take up alot of space.
 

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It does sound expensive to do the roller conversion but I think it would be a great set up. The engine should last forever.
 

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When I built an all roller 455 for my lemans. I ran harland sharp rockers. Crane retrofit lifters. And got a custom grind cam from kaufman racing based on the engine info i had given them. They may have a grind for what you are going for.

I cant speak for stock valley pan clearance as I used aftermarket ones on mine.

I'm not sure if this has been mentioned yet but stock length pushrods were incorrect and I ran a set of big ford pushrods that worked out to be the perfect fit. Sorry I don't remember the part number but it saved me from having to buy expensive customs.

Oh and don't forget to change the distributor gear to a bronze one. The iron ones wont last long at all

This is a pricey upgrade but really ran well for me. :thumbup:

hope this helps some.
 

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Just a slight distinction on what Gruesom said, he is spot on for race stuff.

How big the solid roller is makes a difference on what it needs. A solid does need the lifter bores restricted, but they dont absolutely need the lifter brace until you are over .650 lift. It also depends on the lobe profile, more aggressive profiles need the brace, something mild for the street might not. I used one anyway on my stroker 467, cheap insurance. Also it depends on the timing events, duration, and lift as to what you need to do with the heads.

A small mild cam can still be a roller its not a requirement for a roller to be a huge race cam. What you want to do with the car dictates the cam specs, along with gearing, weight, compression, etc. People were running roller cams before we had Edelbrock/Wenzler/Kaufmann/Tiger heads, you just need to make the cam fit the rest of the engine.

To use a roller cam you will either need to run longer valves, or lower the spring pockets to fit the springs required. I went with longer valves.

I have stock valley pan on mine, it cleared no problem. Also running ported Edelbrock 87cc heads that flow 330cfm. The cam is a 270/[email protected] on a 110LSA. The intake is a Victor with the 4500 flange, the ports are so big most other intakes wont fit these heads.

The cost of just the valvetrain parts is around $1k for both the solid and hydraulic rollers. Its more expensive but they work very well. I am using the BOP distributor gear, its not bronze so it doesnt leave shavings in your oil but it is designed to work with a billet steel cam.

Some engine porn for you.


 
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