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1968 435HP selection

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Old Oct 30, 2006 | 09:20 PM
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Default 1968 435HP selection

I completed a frame off restoration on my 1968 Vette about 7-8 years ago as a 390 HP and have had nothing but fun since. I have the tank sticker and it was an original 435 HP car. Everything is original except the engine. The M21 manual trany, 4:11 rear end, 4 bold mains (right date coded block) are in good shape. I would like to put it back to a Tri power but am unclear as to what internal combination will give me a drivable car. Now looking for original heads and intake combination. Am currently running Power Seal L2300F-30 pistons and a Crane Power Max H286-2 cam with matching lifters and springs. Compression ratio is just under 10:1. I am not looking for a spec engine but Tri Power that is drivable. Any ideas???
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Old Oct 30, 2006 | 09:55 PM
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Default Why Not Go Stock ???

Originally Posted by james.frazita
I completed a frame off restoration on my 1968 Vette about 7-8 years ago as a 390 HP and have had nothing but fun since. I have the tank sticker and it was an original 435 HP car. Everything is original except the engine. The M21 manual trany, 4:11 rear end, 4 bold mains (right date coded block) are in good shape. I would like to put it back to a Tri power but am unclear as to what internal combination will give me a drivable car. Now looking for original heads and intake combination. Am currently running Power Seal L2300F-30 pistons and a Crane Power Max H286-2 cam with matching lifters and springs. Compression ratio is just under 10:1. I am not looking for a spec engine but Tri Power that is drivable. Any ideas???

WHY NOT GO STOCK ??? use original stock specs & you will be sure not to have trouble with a streetable regular octaine drivable fun car ?
ZIXXX PACKER
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Old Oct 30, 2006 | 10:10 PM
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Default Raise Compression

Not sure if original heads will increase compression too high. Current heads are 94CC closed chambers. Are you able to run 93 octane in yours?
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Old Oct 30, 2006 | 10:12 PM
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Originally Posted by 427SIXPACK
WHY NOT GO STOCK ??? use original stock specs & you will be sure not to have trouble with a streetable regular octaine drivable fun car ?
ZIXXX PACKER
The parts will cost about the same and a 435 is DEFINATELY streetable. Only a non-believer or someone that dont have one would tell you different. And 435`s are great fun otherwise why would those without one always want one

Last edited by Ironcross; Oct 30, 2006 at 10:14 PM.
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Old Oct 30, 2006 | 10:17 PM
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Default 93 all day every day !!

Originally Posted by james.frazita
Not sure if original heads will increase compression too high. Current heads are 94CC closed chambers. Are you able to run 93 octane in yours?
93 all day every day !!
no problems at all............
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Old Oct 30, 2006 | 10:24 PM
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Default Yeah!

Sounds like a plan! Now all I have to do is continue to bid on heads and intakes for a 2007 project!
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Old Oct 30, 2006 | 11:49 PM
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A 435 car is "streetable", but is tempermental. IF you did it strictly original, its not an easy car to live with today in my opinion. 12-1 compression, solid lifters ect...And if a 67 or 68, closed chamber heads. I am very curious to know how many restored 435 cars have been "fixed" with internal changes to aid their owner's in keeping them together. This was a production car, and was used by its owners for years. But is it fun to drive around in a 68 435 with 370's and an M21 in traffic? Its impossible. (In California)

A 390/400 car is a different animal, and is well mannered. You never pull the valve covers off, or play with the timing or jets. Why should you? On the other hand, a 435 car needs to really move...I built one (a 435) absolutly to the numbers stock, and its neat, but not real usable in many ways. Ultimate response would be to build a numbers motor to put on a stand, and one you can use.

My engine builder says that he can make my "L-88" (late 69 spec) streetable. I'm betting he cant, but enjoy paying for it anyway.
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Old Oct 31, 2006 | 01:10 AM
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Originally Posted by international blue
A 435 car is "streetable", but is tempermental. IF you did it strictly original, its not an easy car to live with today in my opinion. 12-1 compression, solid lifters ect...And if a 67 or 68, closed chamber heads. I am very curious to know how many restored 435 cars have been "fixed" with internal changes to aid their owner's in keeping them together. This was a production car, and was used by its owners for years. But is it fun to drive around in a 68 435 with 370's and an M21 in traffic? Its impossible. (In California)

A 390/400 car is a different animal, and is well mannered. You never pull the valve covers off, or play with the timing or jets. Why should you? On the other hand, a 435 car needs to really move...I built one (a 435) absolutly to the numbers stock, and its neat, but not real usable in many ways. Ultimate response would be to build a numbers motor to put on a stand, and one you can use.

My engine builder says that he can make my "L-88" (late 69 spec) streetable. I'm betting he cant, but enjoy paying for it anyway.
Not exactly true! If your mechanic cannot make a L88 run on the street, get a new mechanic. I have run one of my L88`s just over 28,000 miles and driving into a 4.11 gear. The 435`s are merely L72`s with a tri power setup. And the compression ratio is 11-1 not 12-1. However the L88`s are 12.5-1. Racing gas is required with that high of compression. The only thing it cant pass is a gas station.
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Old Oct 31, 2006 | 08:00 AM
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Originally Posted by Ironcross
Not exactly true! If your mechanic cannot make a L88 run on the street, get a new mechanic. I have run one of my L88`s just over 28,000 miles and driving into a 4.11 gear. The 435`s are merely L72`s with a tri power setup. And the compression ratio is 11-1 not 12-1. However the L88`s are 12.5-1. Racing gas is required with that high of compression. The only thing it cant pass is a gas station.


though the best upgrade in my opinoin is converting to a roller cam in favor of the solid lifters for more streetable manors
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