Guess it's about time to lock down which engine I want to build/have built as I need to get the heads so I can weld up the side exhaust, and to get the heads I need to know which chamber volume (69 or 76 cc) to get the compression right. I've pretty well decided to go with AFR 210cc or 220cc race heads for good flow, and have several dyno sheets of 406 motors making 550-570 HP and 430-450 ft-lb at 2500 RPM using them (210 cc) so I'm certain I can get the power I'm looking for. Just need to decide what to stick under them, which will factor into whether I get the 210 cc or 220 cc ones.

The Candidates

First possibility is a 396" SB. I have a good "010" 350 4-bolt block sitting in the car now as my mock-up block that would make a suitable foundation. I could get a rotating assy from Flatlander and have my machine shop machine/clearance/check/assemble the short block for me. I could check/assemble the short block myself, and have done so in the past, but I'm just not in the mood to do the bottom end this time, and the cost to have the machine shop do it is pretty reasonable.
Pro since the 396 BB is a "correct" motor for a '65, this could be good for some jokes when getting the car "Not Flight" judged ;)
Con displacement isn't really that big, and I tend to like more over-square motors.

Next candidate is a tried a true 406. JR Racing has a nice deal on short blocks with flat-top pistons that give a nice 11-ish CR. I've got specs for a couple of setups as mentioned that make very attractive power and good low end torque using the 406.
Pro good source for an "off the shelf" short block at reasonable cost
Con can't really think of any

Final candidate is a 414. I like the 4.155 bore to 3.8 stroke combo and it should be easy to get clearance for the modest stroke increase. I can get a rotating set and have the machine shop set one up, but I would need to find a good 400 block somewhere. Speed-o-motive has a nice short block combo, but I'm leary from the mixed some good/some bad responces people have had in dealing with them.
Pro Really like the combo
Con need to find a good 2-bolt donor block (and have converted to 4-bolt center mains)

Others: If you step up to the aftermarket blocks then 427/434 become possible, but it's quite a cost increase. I'm sure the blocks are much better than the GM production ones, but do I need that for a 500-550 HP mostly street toy engine?

Enough ramblings by me, I'm looking for ideas/suggestions/pros and cons, and maybe someone whos shop would like to build a nice 410/414/420 short block at around $3k ??

-Greg

 

i think i would do the 406

 

Keep it Big Block take that money and build your self a good big block you will have more power and more TQ I just got done putting a 360 in my 68 Camaro and after taking a ride in my brothers big block Camaro I wish I had put a big block in mine you will have much more power per $ and it will look stock too since the car came with Big Block.

Jay

 

Jay - Thanks for the suggestion but I already went through the SBC/BBC process. I've built severl (too many actually) engines recently for the boat and decided when setting up the car that I wanted to do a SBC this time ... just not neccesarily a "small" one :D . I also currently have a SBC Hilborn 8-stack in "mid-conversion" to EFI ... so I'm pretty well locked in on this one.

Vader86 - Yep, there is a lot to offer for the simplicity of the 406 option.

-Greg





[Modified by GregP, 11:16 AM 9/17/2002]

 

Since you have an 010 the 396 is a good deal. I'm sure that $3000 would cover the price of a totally forged 3.875 & 4.125 based block.

The change in % of cubic inches between 396 and 415 is minimal and with everything being equal (intake, heads, & exhaust) I'm not sure how much better the bigger bore with some better unshrouding of the valves would run. The stroke is the same so the piston feet per minute is the same.

From what I've seen and talked to people about is that internally balanced and smaller journal sizes is the only way to go.

 

Here's an out of left field suggestion. Get a GM crate HT 383. Sell the vortec heads and intake manifold and use the dollars to offset the cost. Put the AFRs on it with a Victor intake and a Demon 750. If you substitute a longer duration cam you can pretty well match what Hot Rod magazine did which was 463 hp and 502 ft. lbs. torque. The article was in the March 2002 issue. Basically here's what they did:

HT 383 standard with 4.00 inch bore 3.800 stroke
Hedman Tork-Step Headers
Pertronix Flame Thrower HEI
Speed Demon 750 carb mechanical secondaries
Comp Cams Pro Magnum 1.6 Roller Rockers
Edelbrock RPM Air Gap Manifold
Comp XE282HR hydraulic roller cam
Royal Purple 5W30 synthetic oil (worth 8 hp and 9 ft. lbs.)

Final stats 463.1 hp @ 5600 rpm, 502.9 ft. lbs. torque @ 4200 rpm


They used the stock vortec heads and modified them with higher lift springs and better retainers but I think the AFRs would be just as good.
Just giving you some food for thought.

PS
Tell Juliet I like her article.

 

I'd lean towards the 396, mostly cause you have the block already.
If you had to buy a block I'd definitly say 406.

A 406 sould be able to put out 600hp if you really want it to :D

Remember you CAN build a 434 out of a stock 400 block. There is one between the fender of my '69. Problem is there is no real advantage. Rod ratio get horrible, keeping the compression ratio down is a real trick. and there is little HP gain ( but you can put the nice 427 badge on the hood, not that anyone will believe you...)
A 406 can be made to rock, but so can a 396...

 

I'd go with the 406/414 if you could lay your hands on a good block. No matter how you slice it, it has a .125 larger bore and that is always good.

I'd use the 220 cc heads. You aren't going to weigh too much and the EFI will take care of any driveability issues. I doubt there will be any regardless.

Unless you got a killer deal on the 3.800 crank, I doubt it's worth it. But of course, cubes are cubes, and if you end up in the 1.3-1.4 HP per cube area we're talking 10 hp or so. More is better, but not worth spending a lot extra for.

Good luck....this is going to be a neat ride!

JIM

 

406 :D :cheers:

 

Thanks guys, keep the comments coming. I'd like the 414 if I can locate a block, if not I'll probably do the 396 as I don't think I need/want to pay the price to step up to a World or Dart block.

Playing with CR's a little it looks like all the combos would prefer the 69cc chamber heads with flat tops (-5cc), and I always think you get better power from flat tops and small chambers than domes and larger chambers.

Only other possible question is if the 220cc heads would be too large for a possible 396" combo. I know the 210cc will make 570 HP on a 406 (have the dyno sheets), but think the 220cc will be a better match to the ports on my Hiborn 8-stack manifold. Then I still need to decide standard exhaust ports or spread ports, I planning 1 7/8 tube headers.

Thanks for the comments - Greg

 

I just saw an article on AFR is finally trying to catch up with Dart and producing a 227 cc head also.

Any header above 1 3/4, You should go spread port. I'm still kicking myself in the butt for not using my spread port Brodix-11 heads which required spread port headers. My logic at the time was I already had nice 1 3/4 super comps and custom spread ports would be $800-1000 for headers. I also wondered about drivability issues with heads way above 230cc intakes with 2.10/1.6 valves.

I would use them in a heart beat.

 

gkull - I was planning on stopping at the 220cc heads as the 227cc require offset valvetrain parts.

-Greg

 

Greg:

I got your email but I'm not often at home anymore so I couldn't reply (more on that another time).

Yeah, I still have the 400. Its a 73 2-bolt block with a standard bore. I bought it because it was there but now I need to clean house. I really need to sell the whole thing, so even though you probably don't need the stock crank, heads, and tin, you need to take it anyway (LOL!).

Email me at the address in my profile and we can discuss price and pick-up if you're still interested.

 

GregP, I'd go with the 406. As a matter of fact, I'M going with a 406, myself. ;)

I've had my "feelers" out for a good 400 block for a while (not really actively trying too hard, though, to tell the truth) and finally found one this past Sunday. All I wanted was the block, but came away with the whole engine PLUS a new engine stand.

If you want, I'll keep my "ear to the ground" and see what I can still come up with.

Funny, my cousin (an ASE certified master mechanic) has been biatching at me ever since he heard about me wanting to build a 406. He has a "thing" against siamese-bore engines. Oh, well. That's his problem. I like 'em Okay. They're no different than other engines - if they're built right.

What was it that the indominatable Smokey Yunick said? "An engine don't know what name's on the damn valve cover no way!" (or something to that effect.) :yesnod:

 

I would love to build a 406.

 

Got your message Greg. Good luck on your serach. I might still try to selll it or dump the heads and dress and throw the block and crank in storage. I can't imagine I won't find a car to put it in one day.

 

I've learned to treat 427Hotrod's advice like gold. He is a huge asset to this forum and knows his stuff. :cheers:

That said, my preference would be the 406 first. The large bore is always good. With long rods, you can get close to the rod/stroke ratio of a 350.
You can still call it a "396", because once you overbore the 396, you can get the same 406 cubic inches. Actually, a 0.030" over 400 is 407 cubic inches, (406.8"). A 0.060" over 396 big block would be 407.7 cubic inches.
So you're in the ball park.

The 350 4-bolt is a good block that would make a good foundation for a 383. So if you don't want to buy a 400 block, you could stroke the 350. Yes, a 396 small block would be pretty cool in your C2, I agree. And you'll have a torquey motor, but a limited redline. With forged parts, you might be able to consistently rev to as much as 6200 rpm without it coming apart.
The issue is piston speed, and once you start exceeding 4000 feet per minute, it gets dangerous.

rpm (redline) = 4000 fpm x 6 / stroke...if all forged.
rpm (redline) = 3500 fpm x 6 / stroke...if cast.

For a 396, assuming a 3.85" stroke (and 0.045" overbore), that would work out to a redline of 6,234 rpm with forged parts, and 5,455 nonforged.

You can OCCAISIONALLY exceed 4000 fpm but no guarantees. I wouldn't.


[Modified by MoMo, 11:07 AM 9/21/2002]

 

Thanks everyone. Here's kind of what it boils down to so far.

Since I have a block, if I do all the work myself with my local machine shop I can do a 396" (or 383") motor for about $6.5k for the long block with tin and all the valvetrain stuff.

If I buy a 400 block, add the splayed mains, and do all the machining and balancing locally I'd end up at about $7.7k.

I can place a phone call and have a 406 spayed cap short block drop on my door, then do the cam, heads and stuff and end up with a tab of about $7.5k.

All three options are internal balance all forged. So far I like the Isky RR-570-T cam best, predicts over 400 ft-lb of torque from 2500 to over 6000 RPM, peaks around 550-575 ft-lbs with HP around 550-560 at 6000 RPM. I'd like to keep with a 6500 RPM readline combo, and around the .600 lift (with 1.6 rockers, although the estimated power is really close with the .570 lift of the 1.5 rockers) to keep it easy on the valve springs. I'm pretty well sold on the 220 cc AFR's with spread port exhaust.

If I sell my 350 block (which I'd think would be easy) the cost difference is about $700, but with the 396 the legwork and verifying all the parts "really" work together is my problem. With the 406 a shorblock it's a phone call away.

I'm going to do a little more browsing to see if I might find someone competative to build the whole motor and dyno tune my 8-stack EFI. This project is rapidly running toward the $40k level (when done) so I've got to start slowing the escalation down somewhere. Just not sure yet where that "somewhere" will/should be ... of it it really matters :jester

-Greg

 

Here's another idea. If you've decided to use your 350 block with big valved heads and high flow rates you might consider boring your 350 to .060 over to get a 401 CI displacement with the 3.875" stroke. The more space you provide those big valves to operate in, the better your return. At 4.060" your right at half way to the 400 block. Anyway, interesting topic.

Mark



[Modified by 81vette, 11:03 PM 9/21/2002]