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Topic Review (Newest First)
08-22-2012 04:25 PM
Originally Posted by Jdmoell View Post
I'm a bit dense but I am getting the impression that regardless of what I do with this, or an alternate engine is going to require a torque converter at some point?
I guess all I am looking for is a bit more go. Maybe change to d port heads from butler and call it good? Not much power gains though. I suppose this would give me the sound, not the idle but it may enhance the flowmaster super 44's and the h pipe I have?
If you want to cam the engine so that it needs a looser TC, get w/someone who is familiar w/the power band characteristics of Pontiac engines. If you buy an off-the-shelf 3000 RPM stall speed TC it'll prolly flash to 4K behind a 455. This is because many converters are based on a SBC 350 engine unless otherwise noted.

The TC I used behind the 455 w/6X-4 heads I had in a '81 Camaro (cam 236º @ 0.050" lift, 108º LSA, 0.500" lift) flash stalled at 2800 RPM and was a great match to the engine- which had a bad-A idle and the balls to back it up.

The cam was a single pattern. To get around this, I used Rhodes lifters on the intake side only. I had planned to use 1.65 ratio rockers on the exhaust side, but it ran so good like it was that I never bothered.

A 455 built like this would pull your Bonny down the track in the low/mid 13's (providing you had tires that would allow it to hook up), it would sound great and would run on 89 octane. I used a small Holley 4777 650 cfm double pumper w/a Performer intake. Mileage wasn't something I worried about.

In your heavier car I'd suggest a Q-jet or 3310 Holley 750 cfm vacuum secondary carb on a Performer (lighter than stock but no more HP) or an RPM intake. Recurve a HEI distributor to match the combo and a set of 4-tube long tube headers and a limited slip diff.

Odds and ends:

Hopefully you have a TH400 tranny. It should be fresh and have the shifts firmed up and the 1-2 shift valve mod done to allow first gear to be held w/o it upshifting by itself (easy to do). And a 34 element sprag installed. Replace the U-joints if there is any question as to their condition and install a driveshaft loop.
08-22-2012 09:58 AM
Thumpin455 I built a 455 last year and with a small Comp hydraulic roller, Butler ported heads, and a crank kit from Butler it cost me about $4200. It wasnt the least expensive way to go, but I wanted the roller to make cam swaps easier. You could duplicate it with a Summit 2801 or 2802, stock but rebuilt heads, and forged rods from Mr Pbody or some Tomahawk rods and be right at $3k including machine work. Mr Pbody does great work, have never heard anything bad about his engines. I think fuel choice is the only thing he and I disagree on.

As for the converter, you can go into almost any transmission shop and order a Th400 high stall for less than $200, I used to get them between $90 and $140. That converter stalls between 1900 and 2200, which is all a 400 or 455 street engine needs. Any more than that and you are wasting rpm and torque you could be using to move the car. I ran 11s with one of those in a 79 Formula with a 455, they are often referred to as an L88 converter. The reason you want to run a small stall like this is to keep the car from pushing through stop lights with an up sized cam. It will drive like a stock one, but allow more wiggle room than a 1500 stall converter would. The 2801 wont need much stall, but a mild one is not going to hurt anything and will probably help it be more fun to drive.

I would have the stock crank turned, add some Tomahawk rods, forged pistons, get it all balanced, then run a stock 6X head with the 2801 cam in your Bonneville. You can do that with either the 400 or 455 and they will pull your boat around easily. Machine work should be right around $1000 for a local shop to do the work, give or take a bit. Port the heads and the 2802 will be lots of fun smoking the tires. The roller cam I am running is about the same size as the 2801, and it has a very nice idle. Simple, inexpensive, and effective.
08-22-2012 06:24 AM
Jdmoell I'm a bit dense but I am getting the impression that regardless of what I do with this, or an alternate engine is going to require a torque converter at some point?
I guess all I am looking for is a bit more go. Maybe change to d port heads from butler and call it good? Not much power gains though. I suppose this would give me the sound, not the idle but it may enhance the flowmaster super 44's and the h pipe I have?
08-21-2012 04:59 PM
LATECH I have to totally agree with Mr. P Body on this. I would avoid an engine from E Bay. Even buying a usable core can be questionable.
Evenif there is a problem and the company will warranty it,you are stuck with the freight.That can cost a lot.
Plenty of reputable places to get an engine built.Butler performance in Leoma tenn. Central Virginia Machine Service in Burkeville Virginia.
It pays to shop around.
There are plenty of pontiac engines out there. I have 2 I am using, and I am looking at 2 more 400 s. One 68 and a 73. Both are complete just pulled. Both need "freshened up" as the junk yard man says. He is usually straight with me. I garantee I would do more than just "freshen" one up.LOL
08-21-2012 06:42 AM
Mr. P-Body A couple of red flags. Edelbrock carbs are less than desirable, IMO. We've seen a lot of tuning issues, particularly on larger engines. It also lists a "single pattern" camshaft, completely unacceptable for a Pontiac. Needs at least 6 more degrees of exhaust duration. Eagle stroker "kits" use H-beam rods (may be a typo) not I-beams. The only real increase in strength over the factory stuff is in the connecting rods. Pontiac cranks are as good or better than most others of the era (Eagle's casting IS the best aftermarket casting "out there").

There is no name of the company that is building these. E-Bay is a BAD idea for a "no name" rebuild.

08-20-2012 09:40 PM
WDCreech That is a very good deal and should be plenty strong for a street/strip engine, but I still recommend that the rotating assembly be balanced. If you decide to order it, ask how much additional charge to have it balanced.

08-20-2012 07:30 PM
Jdmoell From an ebay listing: Worth considering?

Pontiac 400/461 stroker motor 420hp , READY TO RUN!! No need to track down all the components necessary to complete the engine, quality parts are installed, and adjusted for easy start-up and smooth performance. An Edelbrock 750cfm carburator with electric choke is supplied, for easy cold weather starting, along with a 50,000 volt HEI distributor - 8mm wires and plugs. A NEW timing cover-water pump-balancer-aluminum valley pan-chrome center hole valvecovers are installed, topped with a low profile Professional Products/ProComp intake manifold.

The block recieves the following machining: Bore and hone- deck gasket surface for positive gasket retention. The rotating assembly is by EAGLE, featuring a cast steel 4.25" stroke crankshaft, with 6.800" long forged I-beam rods and Mahle forged pistons. A TREMENDOUS increase in bottom end strength, over the OEM Pontiac parts!!

The heads recieve a 3-angle valvejob with gasket surface milled, assembled with matching new springs and positive valve seals. The Stage II camshaft used has specs (224`@.050" with .470" lift on 110`LSA), providing a LOPING sound in the the exhaust, letting everyone know there is something special under the hood!

This engine is BUILT TO ORDER, with several blocks ready to build, assembly takes only 3-4 weeks to complete, AFTER recieving payment thru PayPal or U.S.Post office money orders.. The engine will be painted the color you choose, with restoration quality finish and looks GREAT under the hood!! Shipping is quoted, please give your city and zip code, for accurate shipping cost!!! This motor carries a 90 day, parts and workmanship guarantee, after start-up. $3995
08-20-2012 07:20 PM
Jdmoell Again I thank you all for your advice. It's nice to bounce ideas off of people that know what they are talking about. As I run financial numbers in my head I am thinking that a 455 build could run into about 4 grand. I would have to get the heads and block machined...around 1800-2000? Then cam, pistons etc...probably another2k? That being said what about this engine on eBay? I have time to work things out finaancially...and yes Inwould have to have someone assemble the parts for me so not much "satisfaction" in building an engine...again this is only an shortly.
08-20-2012 11:37 AM
beertracker Here is a cam for your consideration; Summit Racing SUM-2801 - Summit Racing® Camshafts - Overview -
If you want more duration you can get a 2802 cam. Summit offerers these in kits with lifters also.
A Pontiac 068 cam would also work.
08-20-2012 08:01 AM
Originally Posted by Jdmoell View Post
New to the site with stupid questions...I have a 1966 pontiac bonneville that I have owned now for 26 years. Can finally afford to do a few mods...the engine is bone stock idea on heads or year 72-76 from some donor pontiac in Alaska.

will be a daily driver and family car and very basic horsing around in...

I am wondering if this hair-brained scheme of mine is sound:

Looking to add kit from e-bay:

995-16 Valve Springs
740-16 Retainers
611-16 Valve Locks
503-16 Valve Seals
7775-16 Hi Tech Pushrods
Assembly Lube

the specs on the cam are:

NUMBER 51-600-9

Valve Setting in/ex hyd
Range 1700-5500

Cam Grind
Number 283THR7

adv: in 283
ex 303

@.050": in 227
ex 241

Valve Lift @ 1.5:1
in .513
ex .498

Lobe Sep.
Angle 107

Also looking to add:

Dual quad set up, idle to 5500rpms, dual 600cfm manual choke carbs with universal linkage.

Just wondering if this is reasonable to do...not looking to do any major machine work. This engine has 5000 miles on it and runs smooth on 89 octane...sluggish yes but smooth. Please advise. Thank you
That's a classy ride. IMO you'd be doing it and yourself a disservice by turning it into a fender slapping rough idling 'hot rod'. That said, you can certainly use enough cam in the 455 (something in the 230-234 degrees @ 0.050" lift duration along w/a 108 degree LSA) to get all the idle you could ever want- w/o killing the best part of the Pontiac engine- its bottom end torque. A cam in that area will not require a high stall torque converter and will run fine w/2.73-3.55 gears (I used 3.31 gears behind a 455 in a Camaro and LOVED them).

That car would do great with the 455 in it and along w/the 6X heads- especially if they're the 6X-4 heads (the "dash-4" is a "secondary" identifier, explained here). The 6X-4 heads have a smaller combustion chamber so the compression w/a 455 will be better than if you were to use a 455 head w/their larger chambers.

I agree a single 4 bbl like the Q-jet will work great- but if you're bound to put dual fours on it, go for it- just be prepared for the tuning and possible loss of performance. Get rid of the points distributor. I like and use the GM HEI but the HEI won't fit using some dual four intakes. You can use a points eliminator kit in the stock points-type distributor if it's in good shape.

If it was me, I'd drive it w/the 400 until the 455 was built. And while accumulating the parts to do the 455, I would be doing some heavy researching of the Pontiac engine in general. It's not a Chebby, so much of what you read won't apply to the Pontiac.

Some info to get you started:

Pontiac info and sites
Pontiac V8 engine
08-20-2012 07:19 AM
Mr. P-Body Agreed with LATECH. You would HATE that cam. As an engine builder and been onvolved in thousands of "projects" over the years, many times, one's "eyes" are "bigger" than their stomach. Rumpy-rump engines SOUND cool, but are a pain to operate.

A Bonneville is a classy "dark sider". That's what Pontiac people use to refer to the "big" cars. it is a TANK compared to the Pontiac "performance" cars of the era (GTO, Catalina, "2+2", Ventura). The Bonny has a longer wheelbase than Catalina. A nice "cruiser" is the best thing to do with the Bonny, IMO.

If you're REALLY interested in pumping up the Poncho, get Jim Hand's "How to Build Max-performance Pontiac V8s" published by SA Designs. Get educated on the strengths and weaknesses of the Pontiac.

The 400 block is physically stronger than the 455 block. The "stroker" kits make a much ore effective engine than a "built" 455. Cylinder head casting numbers are among the most imnportant pieces of information you can provide. Compression is controlled by the chamber volume in a Pontiac, not the piston configuration.

08-19-2012 10:23 AM
LATECH A good sounding car can be easy. Decent headers and a dual exhaust with a crossover pipe. Heat crossovers in the heads should be blocked(recommended)
08-19-2012 09:47 AM
vinniekq2 dual quads and lopey idle does not make the car fast or fun to drive.I mean no insults but,if you are not a gear head dont use 2 carbs. If you want the look and the fun first,consider hiring someone to do the work.

I have an idea that might give you the cool factor you want. You will have to do the research yourself,,,,
1984 corvette had what looked like dual 4s but was actually dual fuel injection(2 throttle bodies) edelbrock makes a conversion where fuel injectors are drilled and tapped in the individual runners and the throttle bodies are converted to dry,,,air control only.
you could do this same thing except convert the low rise dual 4 intake for a pontiac and use the corvette style bodies ( look like carbs under an air cleaner).Talk to latech about a "small" camshaft for sound,use full 3 inch exhaust and enjoy driving a modern ish fuel injected cool sounding car that performs well.

If you want serious power,then you will need more items.imo,I think thats enough for a daily driver and the fi will perk up the low end
08-19-2012 09:40 AM
LATECH [QUOTE=Jdmoell;1584034]
Can finally afford to do a few mods...the engine is bone stock idea on heads or year 72-76 from some donor pontiac in Alaska.

will be a daily driver and family car and very basic horsing around in... [Quote]

The least exspensive route would be a Comp Cams XE series cam. There has been a little contraversy about them in the past concerning wear and failure, but if you follow the break in procedure you shouldnt have any problems.
If it were me , I would run a Comp cams XE 262 in your 5000 LB tuna boat.
Stock compression ratio is 8.0 to 1 if you have the # 7J2,7K3, or 4X heads. If you have a 1973 or later engine it will have lower compression heads and some power making capability will be lost.
First thing to do is to ID the motor you want to run. Get year date code from back by the distributor.Also engine casting number. Then get the numbers from the heads.the number will be on the top of the center 2 exhaust ports.
Seeing that you have a 455 in bare form, that would be your best bet to build.
First, you would be able to keep the 400 you have as a runnig spare, and if you are going to spend money to build an engine, dont take apart a perfectly good running engine, build a non runner, end up with 2 engines.

Also the 455 will make better power for the street with your heavy sled. There is no replacement for displacement.

Quadrajet carbs and stock pontiac intakes work real good for a street build, and would be an attribute to your 455 build.
If it were me, I would build the 455.
08-19-2012 09:12 AM
Jdmoell Wow! Thanks to all of you for your input! Maybe the way to go is to build the 455 block that I have with 6x heads. On rethingking this thing and being honest with myself, I just want dual quads and a lopey idle. If the above will accomplish this then there is a good starting point. If other options are available then please let me know. I am open to all suggestions and trying to keep costs down...who isn't?
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