427 build advice
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Its update time. Well I have gotten quite a bit done since my last post. I have pulled the engine and transmission and just about taken everything apart. The only thing left on or in the engine is the crank and the pistons. Here is the good, bad and the ugly. To start with the block is a 454 two bolt main. The crank is a 427 casting number 6223 and the pistons are speed pro 16.8 cc domes. I couldn't find any numbers or information on the cam so it looks like I will be getting a new cam in the next couple of weeks. I am thinking about going with a comp cams Xtreme Energy P/N K11-246-3. The specs are 274/286 duration, 230/236 @.050" lift, .552/.555 lift, and .325/.327 lobe lift. I think this should work well with the AFR265 heads that I want to use. It should also still be able to provide the vacuum needed to operate the headlighs and windshield wiper door and brakes. If anyone has any other recommendations on a different cam, please feel free to chime in.
Le Mans Master
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From: Gladstone MO
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Myself, I'd get a set of ARP main studs, and get in touch with someone like Chris Straub or couple of other guys here that seem to do pretty well in the cam department.
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You've got decent parts...don't worry about the 2 bolt main part. I have a 2 bolt 427 that I flogged for 20 years with nitrous and 7500 rpm shifts and it never had an issue. Those are forged pistons right? You've got a steel crank...you're in business!
I'd put some more cam lift in it with the good heads and you probably don't need that much lobe split with them either.
JIM
I'd put some more cam lift in it with the good heads and you probably don't need that much lobe split with them either.
JIM
Drifting
Joined: Jul 2013
Posts: 1,299
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From: Tri-Cities TN
Its update time. Well I have gotten quite a bit done since my last post. I have pulled the engine and transmission and just about taken everything apart. The only thing left on or in the engine is the crank and the pistons. Here is the good, bad and the ugly. To start with the block is a 454 two bolt main. The crank is a 427 casting number 6223 and the pistons are speed pro 16.8 cc domes. I couldn't find any numbers or information on the cam so it looks like I will be getting a new cam in the next couple of weeks. I am thinking about going with a comp cams Xtreme Energy P/N K11-246-3. The specs are 274/286 duration, 230/236 @.050" lift, .552/.555 lift, and .325/.327 lobe lift. I think this should work well with the AFR265 heads that I want to use. It should also still be able to provide the vacuum needed to operate the headlighs and windshield wiper door and brakes. If anyone has any other recommendations on a different cam, please feel free to chime in.
The semi custom cam I have designed for the AFR heads is 570/570 235/235 on a 108. It will idle at 850-900 rpm, pull 11" and makes gobs of power. This cam in a 496 with AFR265s made 660HP/660#/ft.
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Well I a little bummed out right now. Yesterday I had surgery ou my hip so I won't be turning wrenches on my baby for at least the next week and then my activity will still be limited. To make matters worse the weather here is awesome. I think that I have made my mind up and I will be giving Straub a call on Monday to discuss cam options. I will also need to figure out what I'm going to do to boost my compression. The best that I can figure right now with a .037" compressed head gasket is 9.3:1. So I guess I will also spend some time on the phone with AFR.
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AFR can mill the heads to whatever you want before shipping to you.
JIM
JIM
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its update time. I completely tore down the engine and I found that there is some galling on the piston skirts so it looks like there will be some new pistons in my engines future. The rods and the pins look good so I will be reusing them. I gave the crank a once over and it looks to be in very good shape. The bad news is that in one of the bores there is some pitting that I guess came from the engine sitting. So now the question is, how much more can I bore the block out? It is a 361959 casting, two bolt main block and it has already been bored .060" over stock. So its now 4.310". Can I safely go to .090" over?
Additionally, I have spoken with Chris Straub at Straub Tech. and he has been a huge help to me and I will be ordering my cam and AFR heads from him in the next week or so, providing that I can save the block.
Additionally, I have spoken with Chris Straub at Straub Tech. and he has been a huge help to me and I will be ordering my cam and AFR heads from him in the next week or so, providing that I can save the block.
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Most likely fine. Most can go .100...some .125. Need to have block sonic checked to be sure. Or you could sleeve that one hole.
JIM
JIM
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Well I droped off the block at the machine shop today and hopefully it will clean up to 4.320" and if it does I am going to install a set of Keith black KB227 pistons. If not I will have to bore it to 4.350 and get those size Pistons...wish me luck
Race Director
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From: Millington Illinois
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No way would I rum KB hyper pistons. Go with the Speed pro low expansion forged for similar money. KB hypers are notorious for failures. Personally seen many issues with these.
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Ditto. Put something forged in it.
JIM
JIM
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Ok, based on Jim and Mako's advice I started researching forged Pistons. Speed pro doesn't make anything bigger then .060" over. So I found a set of icon performance Pistons with 28.20 cc domes that should work but the cost is almost double the cost of the speed pro Pistons that I took out. I figure the cost will be justified if it will reduce the chance of a failure. Does anyone have any recommendations for rings.
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Sealed Power/Speed Pro..or Mahle. Ck with Competion Products...they often have great prices on stuff. Their "Howards" rings are re-packaged Mahle's....I've used them. The bag is amrked Mahle and they work great.
Ck with Flatlander also. Sometimes some good deals.
Unless you're married to having a 427..and you already said the crank has been turned a good bit (which isn't the end of the world)...you might look into a 496 buildup. 427 pistons are often pretty pricy and you can put some of the money towards the other parts. Just a thought and an easy way to gain 100+ HP for little more $$$.
JIM
Ck with Flatlander also. Sometimes some good deals.
Unless you're married to having a 427..and you already said the crank has been turned a good bit (which isn't the end of the world)...you might look into a 496 buildup. 427 pistons are often pretty pricy and you can put some of the money towards the other parts. Just a thought and an easy way to gain 100+ HP for little more $$$.
JIM
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Intermediate
Joined: Mar 2015
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Sealed Power/Speed Pro..or Mahle. Ck with Competion Products...they often have great prices on stuff. Their "Howards" rings are re-packaged Mahle's....I've used them. The bag is amrked Mahle and they work great.
Ck with Flatlander also. Sometimes some good deals.
Unless you're married to having a 427..and you already said the crank has been turned a good bit (which isn't the end of the world)...you might look into a 496 buildup. 427 pistons are often pretty pricy and you can put some of the money towards the other parts. Just a thought and an easy way to gain 100+ HP for little more $$$.
JIM
Ck with Flatlander also. Sometimes some good deals.
Unless you're married to having a 427..and you already said the crank has been turned a good bit (which isn't the end of the world)...you might look into a 496 buildup. 427 pistons are often pretty pricy and you can put some of the money towards the other parts. Just a thought and an easy way to gain 100+ HP for little more $$$.
JIM
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Thread Starter
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Well its update time. Since my last post I have gotten my block back from the machine shop. Received everything to assemble the engine, less the pushrods. Had my rotating assembly balanced and assembled the engine, less the pushrods. This weekend I will be measuring for pushrod length. The picture above is of everything mocked up.
I also called "Custom Rebuilt Carbs" and talked to them about rebuilding my Holley 3310-2 but as luck would have it, that carb is too small for my engine. After doing some research, I figured that I am going to need something putting out at least 830cfm.
To date the engine specs are as follows:
GM Iron block bored out to 4.320"
GM forged crank 3.76" stroke
GM forged rods
Icon forged pistons
Clay Smith cam 235/235 560/560
AFR 265 oval port heads
Roller lifters and Comp Cams roller rockers
Edelbrock Performer Air Gap Intake
I want to thank Chris Straub for all of his help so far.
Drifting
Joined: Jul 2013
Posts: 1,299
Likes: 93
From: Tri-Cities TN
Well its update time. Since my last post I have gotten my block back from the machine shop. Received everything to assemble the engine, less the pushrods. Had my rotating assembly balanced and assembled the engine, less the pushrods. This weekend I will be measuring for pushrod length. The picture above is of everything mocked up.
I also called "Custom Rebuilt Carbs" and talked to them about rebuilding my Holley 3310-2 but as luck would have it, that carb is too small for my engine. After doing some research, I figured that I am going to need something putting out at least 830cfm.
To date the engine specs are as follows:
GM Iron block bored out to 4.320"
GM forged crank 3.76" stroke
GM forged rods
Icon forged pistons
Clay Smith cam 235/235 560/560
AFR 265 oval port heads
Roller lifters and Comp Cams roller rockers
Edelbrock Performer Air Gap Intake
I want to thank Chris Straub for all of his help so far.