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Discussion Starter #1
Hi!

Maybe I need to repair my engine soon (reason can be found in another thread). I'd be interested anyway in how to rebuild this engine.
I don't know anything about internal parts of my engine. If I have to rebuild it, I'd like to know how to make it powerfull and reliable. (heads, camshaft..)
I don't need an engine that makes 6000rpm or more, if the power is "available" from idle to 5500rpm this would be best for my intentions.

The car:
428 from 1969
670 heads (will need replacement)
tri power setup
MSD ignition
manual transmisson
headers and a 2,5" exhaust system

I found these parts but don't know if they will be good:

- Edelbrock Camshaft and Lifter set: Edelbrock 2157 Advertised Duration 278/288, Lift .420/.442

- Edelbrock Cylinder Heads: Edelbrock 61575 with 87cc, 2.11" intake and 1,66" exhaust valves

This head is fully assembled and is available with maximum valve lift of 0.6" or 0.55".. I don't know which is better.
I remember that Bear told me to use bare Edelbrock heads and have them assembled by a professional, but I'd only like to do that if the Edelbrock assembled heads ain't good, because I live in Austria and buying parts in the US and have them shipped to someone else in the US who will have to ship them to me is a little bit expensive and complex.

I also found these heads: Tin Indian Performance - KRE Aluminum D Port Pontiac Heads

These might be the same? Kauffman Racing Equipment

Edelbrock or KRE? Or something else?? :)
And do I have to buy some other parts as well? Only thing I know is I need a new head bolt set for the Edelbrock heads and probably new gaskets (I have a complete set from Fel-Pro at home).
I now use Accel 137 spark plugs and have set of new ones already at home. Can I use them on the new heads? And timing will be okay like before? It has been set to 18° initial and 36° max with my MSD Pro Billet distributor without vacuum advance. If a other dist. would work better I could think of buying something else as well, but I don't want to invest too much money, so if the old timing setup will work I won't change it.

Thank you for every comment on this, I'm curious about what the experts will advise me to use!

Chris
 

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Well now, this could get interesting very quickly :D

There are a lot of cylinder head choices out there now that weren't there even a few years ago.
People will probably tend to recommend to you what they "know" or have experience with. I know I really like the way my engine is built and can tell you all about it - but that's just one example. There are many ways to make power reliably with Pontiacs, so be leery of anyone who tries to tell you his/her way is the absolute best, especially if they can't back it up with logic and real results.
I like roller cams/lifters because you can get more power ("area under the curve") without having to go crazy on the amount of overlap and duration the cam has. Both overlap and duration have an effect on street manners - how rough it idles - and also how much idle vacuum the engine makes. This is important if you have vacuum operated accessories like power brakes. Another reason I like rollers is you don't have to lose sleep at night over whether your oil has enough ZDDP in it and whether or not you're going to be unlucky and have a cam lobe 'wiped' during break in. The down side is that roller systems are expensive, and if you choose a solid variety like I did you'll have to check and re-adjust the valve lash periodically (though not as often as some might suggest.)
One thing nearly everyone agrees on is that the Pontiac factory rods need to go. Replace them with some good quality aftermarket forged rods. You can get a set for not much more than you'd pay to have the factory rods reconditioned. The factory rods are always the weakest link in a Pontiac - with the debatable exception of the 455 SD rods --- but those things are awfully heavy. Plus, replacing the rods and pistons gives you the option of going with the longer 6.800" rod instead of the factory 6.625" rod. That's another 'debate topic', but the longer rod because of the geometries involved changes the piston 'dwell time' near top dead center, piston acceleration, and also the point in the crank rotation where the rod and the crank are at a right angle to each other. Some folks think a longer rod is 'better'. I'm one of them, but I can't "prove" it.

Cylinder heads --- now there's a topic for debate and you'll certainly find lots of opinions. In your situation I'd probably choose an aluminum D-port head, either Kauffman or the new Edelbrocks, just because your car is already set up for a D-port exhaust system and that would save you having to replace your headers (or manifolds - I forget what you have) also. The new Edelbrock D-port heads have some very nice looking chambers. The Kauffman's are similar. People have more experience with the round port Edelbrocks like I have, just because they've been out much longer, but a good head porter can do magic with either design.

Either way, I'd still buy them bare and have Dave at CVMS in Virgina build them up for me. I understand that's not a trivial thing for you to do, but I know you'd be happy with the results. The problem with buying any head off the shelf and ready to run is that they generally come with cheaper springs, cheaper valves, and other hardware that's not necessarily top of the line.

You'll probably have to change your ignition timing some because of the heads. Different chambers, different materials, all effect how the combustion flame propagates through the chamber and that's what determines how much advance your engine will "want". The heads you choose will also in large part dictate which spark plugs to use.

Once you've chosen a particular head and combustion chamber, then that will determine which pistons you'll want to use in order to put the compression ratio where your engine will be happy. I'm not familiar with how octane ratings vary between "here" and "there", but "here" on 93 octane and aluminum heads, I'd shoot for a compression ratio of around 10.2 or 10.3:1

Take your time, talk to people you trust. If you can, I'd recommend giving Jim Lehart a call (+1 434 767 9915). He'll tell you the truth and won't steer you wrong.

Bear
 

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Discussion Starter #3
I found some cams with roller lifters.. but the set is 700-1000$. The edelbrock set (hydraulic flat tappet) will cost 170$. I really would like to have all the best parts for my engine, but I cannot spend that much money :(
Same thing with having the heads assembled by Dave, I simply cannot afford it.. If you said the Edelbrock D-Port heads (assembled) are bad and use really cheap valves... I'd have to find a way to afford it. If the fully assembled Edelbrocks are pretty good but not perfect, I probably will use them as they come "out of the box" because of the fact that it will make it much easier to buy and afford them. (heads mentioned above cost 2200$ at Summit and with shipping and taxes they are 3100$)

I now have the 670 heads, they are D-Port heads I guess?
If I use the Edelbrock D-Ports.. which is better? Maximum valve lift of 0.6" or 0.55"?
And camshaft kit, what duration and lift are good for my intentions? The ones I found have Duration 278/288 and Lift .420/.442. But if I don't use Edelbrock there are lots of other choises available.

I have the 66 tri power manifold and the tri power carbs. They will work with the Edelbrock D Port heads?

I'm also not sure if I have factory rods, but I'll ask my mechanic to check them when he removes the cylinder heads. Can he see what kind they are? New ones are pretty expensive.. I'd only like to spend the money if the old ones are bad.
If I can keep the MSD dist. I have now and only adjust the settings this would be good news as well :)
I really appreciate all the information about what I can/should change, but I have to keep the costs low (but I don't want to have bad parts, less power and a none reliable engine)
 

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Parts cost: Cry once when you build it or every time you use it. Up to you. X2 on everything Bear said. If you give Jim a call and have him map out a course of action, and use his services, you can't go wrong. Not cheap, but a reliable, pump gas friendly engine that will produce ample power and last for years. You get what you pay for in this game.
 

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Discussion Starter #5
I absolutely agree with that. I'm not a guy who doesn't care about quality.. it's pretty the opposite. But I simply don't have that much money.
I would be really interested in answers to the questions before, especially if 670 are D-Port heads, if Edelbrock fully assembled heads are any good, which valve lift is better and what camshaft specs. are best for my intentions.

As soon as I know what's the deal with my engine I'll probably give Jim a call to see, if I could afford the things he would suggest me to use. But no matter what, I'll have to take care of the problem and if I know that lets say the Edelbrock assembled heads are "good enough" I can feel a little better because I know that for 3000$ I can drive my car the next years until I have the money to completly rebuild it (and re-use the before buyed Edelbrocks but have them assembled by a pro)
 

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Yessir, 670's are D-port heads.

It's not that the fully assembled heads are 'garbage' -- they're not. It's just that they can be SO much better with a little attention.

There's also nothing wrong with doing things a little bit at a time.

That's one of the reasons I recommended you call Jim. He'll steer you right and will share honest information with you even if you don't 'buy' from him. He also knows how to fit a build into a budget and still hit reasonable performance goals - a whole lot better than I could.

A roller is not 'the only way' by any means. It's just the one I like the best. There are a lot of Pontiacs out there making pretty serious power with flat-tappet cams, even more power than I'm making with a roller in fact.

Rods though, are something I'd consider a necessity even if you have to save somewhere else. By the time you have a set of factory rods straightened, resized, reconditioned, replace the bushings, pin fit, ground and polished the cost will be very close to what a set of forged H-beams would cost but they won't be anywhere near as strong or reliable. Most of the time when a Pontiac engine meets an untimely demise it's because of a rod failure. Wouldn't it be a shame to invest in building a nice strong engine, then have it reduced to nothing more than a big boat anchor because a rod let go? It's just not worth the risk for the small difference in cost. Yes, on various message boards you will find people who will say "I've been running factory rods to 7000 rpm for 20 years and have never had a problem." --- but they are a very small minority. For every one person like that you find, you'll find several hundred ruined engines in the scrap yard that are there because of thrown rods.

Yes, your tripower manifold will fit any factory or aftermarket Pontiac head that has the 'stock' port layout - including round port and d-port. Exceptions I know about are the CV-1 heads and real (or repro) Ram Air V's. You might have a problem with round port Edelbrocks if they've been ported. All the bolt holes will line up ok, but the manifold might not be "tall" enough to completely cover the port openings in the heads. (I ran into this with my E-heads and my factory cast iron intake. That's why I'm running the Torker 1 now.)

I'm not a big fan of Edelbrock cams, just because I've got no experience with them. I do like Comp Cams, Lunati, and Crower. Increased lift vs. increased duration (or both) --- it's a trade off. With increased lift you'll need different springs and perhaps some machining on the spring seats in the heads in order to run springs that will work with the higher lift without going into coil bind. Longer duration is going to tend to have more overlap which has a negative effect on low rpm operation and also idle vacuum. (Overlap is also what produces that nice sounding lumpy idle we all associate with a hot motor.) You mentioned a 278/288 duration cam --- are those numbers for "seat to seat" or "advertised" duration, or are they for duration at .050 lift? If it's seat-to-seat/advertised, then that's a mild to moderate cam. If it's at .050 --- it's very nasty. (My solid roller is 236/242 at .050, 273/279 "advertised" --- but being a roller the opening/closing ramps can be steeper than on a flat-tappet cam so it "acts" like a much bigger flat tappet cam. It definitely idles with some attitude.)
.420 lift at the valves is also moderate, if that's with 1.5:1 rockers. (Mine is .565/.571 with 1.5's - or would be - I'm running 1.6:1 rockers so my actual valve lift is .603/.609). You actually have an advantage with the 4-speed because you don't have to worry about matching up the converter stall to your engine's torque band. You can launch the car at any rpm you choose. If you also don't have power brakes or a/c, then you can completely disregard any concern for idle vacuum and go as nasty as you want on the cam :D

Bear

Bear
 

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Discussion Starter #7
Wow, thats a lot of information, but exactly what I need to know :)
The thing with the "cam" is pretty complex, getting nasty with the cam will make more power and still be reliable with a little worse idle? I don't want the engine to make more than 5500rpm at anytime, I won't race it. But if it puts out some serious torque and hp at low rpm that would be great!

Okay so the Edelbrock heads would be better bare and assembled by somebody else, I'll think of it and calculate if I find a way to do that. If there is a company where they sell new and self assembled Edelbrock heads this would be much easier if they are not too expensive!

That I should really use new rods isn't a really good news, because they are expensive and it will be a lot more work (engine has to come off?).
Is it a very bad idea if everything seems in good condition except the heads to replace them and don't touch anything else? Maybe the rods are not factory originals, I don't know what has been done with my engine before, can I "see" this after the heads are off?
 

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The topic of cam shafts is fascinating, and very detailed - complex. To try to simplify it as much as I can, what you're doing with a cam change is really just moving the rpm at which the engine is 'most efficient' --- peak volumetric efficiency (VE). Peak VE is usually the point where the engine makes the most torque - twisting force - because that's where it's making the most efficient use of its "lungs" -- the cubic inch displacement. This all has to do with the fact that air has mass and requires some time to start moving (and stop moving) when the valves open and close - it doesn't just instantaneously rush into the cylinder when the valve opens. An engine really is just a big air pump. The more air you can make it breathe, the more power it's going to make.

Horsepower is a calculated number. Horsepower is (torque X rpm)/5252. So, if we have an engine that makes, say 500 lb. ft. of torque at 4000 rpm, that's (500 X 4000)/5252 - or 380.8 HP. If we change the cam so that the torque peak now occurs at 5000 rpm, that's (500 X 5000)/5252 - or 476 HP. The engine is not "twisting" with any more force than it was before - it's still twisting with 500 lb. ft. of torque. It's just doing it at a 'faster rate' - 5000 rpm instead of 4000 rpm --- so because of the calculation, we picked up close to 100 hp. If you take a close look at HP and torque charts, you'll see that all engines always have equal horspower and torque numbers at 5252 rpm. That's because of the mathematical relationship between the values.

I know rods are expensive, but if your engine has been detonating it wouild be unwise to reuse the rods that are in it because the effects of detonation may have bent them slightly, and also may have 'elongated' the big ends of the rods so that they're no longer round. Even if you reuse them, you'd want to remove them and have them straigtened and the big ends resized and restored to 'roundness' anyway. It will cost you almost as much to have that done by a reputable machine shop as it would to purchase a set of good forged rods.

It takes presicion measuring tools to check the rods for straightness and roundness. It's not a job you can do with the naked eye. In order to remove the rods for this job, it's best that the engine be removed from the car. I'm not going to say it's impossible to do without removing the engine because it's not.... but doing it that way is so unpleasant and difficult that you'll wish you'd just gone ahead and pulled it. :D
 

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Discussion Starter #9
Thats really interesting! So if I pick a Cam that makes most power at 550rpm would be best, because I don't want the engine to run with more? How much rpm will be best if the engine still should be pretty reliable?

So I wouldn't think of repair the old rods, thats for sure, better new forged ones!
To remove the engine is better if all this has to be done and in that case the clutch can be changed easy I guess :) Another 500$ but I need to soon anyway!

If I change the rods, can I use the old pistons?
 

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Chris, I think you meant 5500 rpm, and you need to be aware of something that hasn't been mentioned: a 428 is a "big journal" block with 3.25" mains. Big Journal engines don't like high rpms (above 5000) or sustained rpm's above 3,000. They don't oil well due to the size of the bearing. That's why everybody (Bear included) is running a big inch motor based off of a 3" crank.....A 3" crank motor will withstand much higher RPM and sustained high rpm cruising. So, that said, you want your engine to do what a big engine does best: Make its power down LOW in the rpm range. You want a cam that comes on at 1500-1800 rpm and is pretty much done by 5,000 rpm. A 428 is a GREAT engine....it just doesn't need to wind way up there to make a ton of power.
 

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Discussion Starter #11
I have set my Tach. redline to 5000rpm from day 1. Almost never pushed it to 5500, I had the feeling that it doesn't like it very much and now I know the reason why.

I found this cam and lifter set: http://www.summitracing.com/parts/LUN-10510472LK/

Basic Operating RPM Range 1,500-5,000
Intake Duration at 050 inch Lift 218
Exhaust Duration at 050 inch Lift 218
Duration at 050 inch Lift 218 int./218 exh.
Advertised Intake Duration 284
Advertised Exhaust Duration 284
Advertised Duration 284 int./284 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.458 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.458 in.
Valve Lift with Factory Rocker Arm Ratio 0.458 int./0.458 exh.
Lobe Separation (degrees) 110


Does that sound good for my engine? I now thing of using these parts:

- Edelbrock heads and head bolt set (let them be assamble by a expert if I can afford it)
- Camshaft and lifters as mentioned above
- New rods from Scat (there are floating and press fit style and alloy or chromoly steel connection rod bolts available.. what do I need?)
- New gasket set for the engine

Any other parts I should think of? Bearings? Pistons?
 

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Good advice from GeeTee, as usual. Thing I'd say would be don't get in a hurry. Get used to the idea that you probably won't be able to buy all the parts at one. For instance pushrod length will need to be chosen after a trial assembly of the heads and rest of the valve train so you can ensure the contact pattern on the valve stems is where it needs to be. Likewise sometimes pistons come later too after you know for sure the chanber sizes in the heads. Best advice I could give you on choosing a cam would be (you guessed it) call Jim. :D

(I like floating pins myself)

Bear
 

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Discussion Starter #14
I'll ask Jim. Now I know some good questions!
Maye I can contact him by e-mail. If I can read the answers I can take more time to think of it, there are always some words that I have to check in the dictionary if it comes to engine specific terms.

I want to rebuild the engine during winter, money isn't longer the big problem, I won't go on holiday and invest the money that is needed to make it good. I don't like the idea of investing a lot of money but save on some important things that also need attention (rods, maybe timing gear since I read that Edelbrock recommends that..)

I'll plan carefully what to do, starting with this topic! :) Your comments help me a lot, so don't reserve any good ideas of what to do to get more power and a reliable pump gas engine. But even if I use my holiday money, the budget is limited. So a good compromise between the "wanted" things and the "necessary" things has to be found. I hope Jim can fit this into my budget (3000-3500$ for parts max. because I need to ship them and pay our taxes which are 20%)
 

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Discussion Starter #15
I've asked Jim and got a reply with some good basic information. Now he knows what I want to build and I'm waiting for his comment on this.

For sure until now:

- new heads and head bolt set
- new camshaft and lifter set (roller)
- new timing chain and gear
- new rods
- engine oil cooler
- gasket set

If I can keep the old pistons and don't have to machine the cylinders I would be able to afford that and I guess the right parts could build a powerfull and reliable engine.
My mechanic said he'd like to see a bigger oil pan and/or a oil cooler. This shouldn't be a big problem I think. I'll go for the oil cooler and use my old pan because a new one is pretty expensive and can be changed later (after I have saved some money again). For now I think it's better to invest in the rollers instead of the hydraulic flat ones like you and Jim told me :)

If we talk about horespower.. do you mean engine power or wheel power?
 

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... it depends. Usually I quote engine (flywheel) torque and power figures for my engine because those are the numbers I actually have from when I broke it on in the engine dyno.

I've never had it on a chassis dyno, but if I did, that would give me rear wheel figures.

Don't get too obsessed with either set of numbers though. They aren't absolute. The same engine will produce different results on different dynos because no two dynos are exactly the same. Plus, some shall we say "less than scrupulous" operators will intentionally "recalibrate" to yield higher numbers because they know their customers like getting big numbers.

The real value of a dyno is the ability to make changes while you're there and find out if those changes make things better or worse, on your engine, on that day.... beyond that, it's still just an approximation.

Bear
 

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Oil capacity in a Pontiac is generally a non-issue, IMO. They hold 6 to 7 quarts of oil with filter. You can add a cooler if you like. I've never run one. Big aftermarket pans can be problematic with clearance and quality control issues. It sounds like you are on the right track. Research and planning done now will save you big $$$ and give you a much better performing end product.
 

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Discussion Starter #18
I'm happy that I get so much help from everywhere. The idea with oil pan or oil cooler came from my mechanic (the one who will finally do most of the work), but he has no special experience with Pontiac. He has worked on some Chevy I think, but mainly Ford.
I never had problems with oil pressure or temps, thank you for the information about this. I won't spend money on parts that are not needed. Also I don't race the car or drive big distances on the highway.

After my mechanic has removed the engine and checked it I will order all the parts needed from Jim (and Summit if I have to buy the heads there) and with all the collected information I hope the end product will be pretty good.
If I can reach the 400-450hp (flywheel) that would be really nice!
 

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It should make those numbers no problem - not even breathing hard.

I'm using a Mildon pan on my car, their part number 30355, along with their pickup - 18425. The pan has a baffle and a kick-out on the drivers side so that it holds more oil than stock (helps with cooling). If you're running the factory style starter and headers though, it's a pain to get the starter in and out with this pan - probably requiring loosening the drivers side header a little at the heads so you can move it up and out of the way a little. I'm not running an oil cooler.

Bear
 

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Discussion Starter #20
I use a factory style starter. Removing the starter is almost impossible with the headers in place.

Will it be difficult to remove the engine from my car?
66 GTO with power brakes, power steering, AC (not installed)..

Something I should know when we try to remove it?!
 
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