[Chuck_Neste]

Hello All,

I am planning on building a 400/ zero deck that is stout. I am using the Turbo 400 tranny and have 3;55 rear end gears on a 70 firebird. I am planning on using 6x heads with a static compression of around 8.7. I assume I would need to find some flat top pistons. has anyone tried this cam or can recommend it as I dont plan to do 100 mph or can recommend something that will provide great midrange response and still have vacuum at idle

Thanks
Chuck

Voodoo Hydraulic Flat Tappet Cam & Lifter Kit - Pontiac V8 262/268

Product Description
Lunati's Voodoo series of Hydraulic camshafts deliver more area under the curve than any other series of Hydraulic camshafts. This means more throttle response, quicker acceleration, more vacuum, better efficiency, combined with maximum horsepower and torque!Hydraulic Flat Tappet Cam. Torque Monster for 400-455 c.i. daily driven street performance vehicle. Excellent torque and horsepower production with heavier emphasis on the low to mid range. Will work in tri-power applications with larger 389-455 c.i. engines. Choppy idle!

• Advertised Duration (Int/Exh): 262/268
• Duration @ .050 (Int/Exh): 219/227
• Gross Valve Lift (Int/Exh): .468/.489
• LSA/ICL: 112/108
• Valve Lash (Int/Exh): Hyd/Hyd
• RPM Range: 1300-5500
• Includes: Cam & Lifters (#71951PR-16)

Part Number: 10510702LK
Previoius Part Number: 60902LK

 

[Chuck_Neste]

Using these pistons, I would see a static compression of 8.8. i assume the static would be a little higher depending on cam.

numbers based on bore of 4.15 .040 crush and zero deck using 100 cc heads( 6x)

http://www.summitrac...ew/make/pontiac

Your displacement is 405.80 CID
The Compression Ratio is: 8.80

Chuck

Possible Piston choice.

http://www.cnc-motorsports.com/pistons-1/keith-black-pistons/keith-black-kb304-030-hypereutectic-flat-top-pistons-4-150-bore.html

 

[Chuck_Neste]

Thanks all for the replies, let me look around for cam set ups as I try to put together a good combination. I am in fear that if I get a smaller I cam, I wish I went bigger and if I got a bigger cam, I should of went lower.

Looking for a dynamic compression of a of 9. no more than 9.5 . I work from home and the car is not a daily drive for work. I don't know where you got the 8:1 ratio as I assume the flat top pistons were not factored in but I am thinking 8.8 to 1 for a static baseline.

Thanks

Chuck

 

[Chuck_Neste]

I am assuming a # 15 head with 87 cc would bring my CR to 9 to 1 but will need valve work / hardened seats.

 

[Chuck_Neste]

Thanks for the replies. its been 20 years since I played with a muscle car and now I get a chance to do it right. using 6.x heads, Would these pistons be suitable. Cr is about 9:1

I rather skin the cat with 6x heads than 15's. I have the money but don't want to go all out.

L2262F30
400ci Stock-Type Piston, .030'' OverborePiston Dia.: 4.150''[*]Piston Top: -6.7cc Dish, 4-Valve Reliefs[*]Pressed Pin[*]Comp Ratio: 10.24:1 w/69cc Heads, 7.16:1 w/114cc Heads[*]Ring Grooves: 5/64'', 5/64'', 3/16''[*]Sold as Each

 

[Chuck_Neste]

If I get a set of older late 60's open chamber # 15 heads, Would I have to have the valve seat hardened. I think 87Cc would bring me into the low 9's. Any thoughts and will the ram air exhaust manifolds bolt up. if so, I am in

. Any pros / cons /comments from the peanut gallery

Thanks

Chuck

 

[Chuck_Neste]

Ok,

If I went with a 6x-4 head, I can get about 8.8:1 with the right piston. if I got the 15 head, I will be about 9.2 or so. What is the power loss for HP and Torque between these 2 compression ratios. Looking for facts and opinions.

Thanks
Chuck

 

[Chuck_Neste]

If only I wa sin my 20's again I may go 11:1. Age mellows you out.

I found a set of Pontiac 6x-4 93 cc heads. . Need to see what piston choices I have and off to the machine shop to balance the rotating assy.

Thanks all

Merry Christmas

 

[Chuck_Neste]

Hello All,

This is what I am thinking base don what I found so far. assembly starts right after the holidays

400 +.030 Block Zero deck

Pistons for about 9..2 to 9.4 compression

http://www.cnc-motorsports.com/pistons-1/keith-black-pistons/keith-black-kb304-030-hypereutectic-flat-top-pistons-4-150-bore.html

Pontiac 4/x heads with ram air exhaust manifolds

Edelbrock 650 Carb

Performer intake.

Lunati Cam/ lifter /spring set

• Advertised Duration (Int/Exh): 262/268
• Duration @ .050 (Int/Exh): 219/227
• Gross Valve Lift (Int/Exh): .468/.489
• LSA/ICL: 112/108
• Valve Lash (Int/Exh): Hyd/Hyd
• RPM Range: 1300-5500
• Includes: Cam & Lifters (#71951PR-16)

Merry Christmas

Chuck

 

[Chuck_Neste]

Hello All,

I seen a lot of youtube videos and articles on adjusting rocker arms but I found this article which is what I remember back in the day to work. The only question I have is that do you perform the following with the lifters primed or dry?

http://www.pontiacstreetperformance.com/psp/rockers.html

Thanks

Chuck

 

[Chuck_Neste]

Hello All,

Back from the holidays and I am making progress. I need some input about putting a motor together. Based on the data below, Any ideas on Dynamic / static compression ballparks?

1973 400 Block +.030 over

1974 GTO 350 46 heads ( large valve) about 89 cc ( not measured yet )

sealed power l2262 pistons (+6.7)

ramair exhaust manifolds repros

roller tip rockers 1.52

Jet carb Rochester 4 barrel stage 2

Cam

Lunati 262

HYD 1300-5500 262 268 219 227 .468 .489 112°

Thanks

Chuck

​

 

[Chuck_Neste]

Thanks for the reply, All parts were already bought. I was able to get the 73 400 block and crank already machined for the cost of the machinist bill as the owner of the block decided to go in a different direction. I am paying a little extra to zero out the deck. I assume I am running around 9;1 and I assume I am close to 450 ft of torque and don't expect to break anything using my 12 bolt 3:55. but may be the max I want to put on the 700R4. The only thing I have not bought yet is the stall converter which I think an 1800 would be good. maybe if I had some extra money, I may do a stroker but I have a 3 Kish budget and the alternative would be buying a used motor but you never know what you are getting

Thanks all.

 

[Chuck_Neste]

This was the way I did it with chevy engines. I see a few different ways of doing the rocker arm adjustments so sometimes too much info is bad