Unforgiven Project

I have an open question for you all...

First .. the question..then the reasoning.

The question is.... should I de-tune the race motor I had built... or, should I lower the compression with new pistons to turn this motor
into a nice dependable street car motor.

The reasoning is..... I am going to be fading out of the race truck scene in a couple years do to the fact that it is taking a toll on my body.
The wife would like for me to build her a 1966 chevelle (like she had when we were in high school).
I was thinking that if I could find a car for around $15 - $20,000 .... I could finish it in a short amount of time, and put my race motor into it.

I have to buy new pistons anyway , so ... What I have in there now are 11.5 : 1 flat tops. And the blower pushing up to 12 lbs of boost.
I was thinking about lower the pistons to 10 : 1 , and lowering the boost so I might be able to run the pump E-85 fuel.

So we dont have to search back through my thread.. I will refresh on what I have now.

383 SBC Bow Tie Race Block
Forged Scat Rotating assy. Balanced to 0.02 gram ( 11.5 : 1 static compression)
Promax 200 Aluminum Heads (2.02 valves) (1,6 roller rockers)
177 Weiand Blower ( manifold ported extensively) plus ( multiple upper and lower pully combo's)
Holly Super Sniper EFI
Hyperspark ignition
Howards Cam 243/253 @ 0.05 dur .507/.530 lift (1.5 rocker ratio) 112 LSA
1- 7/8 headers.

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This motor has alot of torque... So I think I can afford to lose some for the drivability factor on the street.

My wife would drive this car to work daily, and we would like to play on saturday night.
Don't need a drag car... just a better than average saturday night special ( if you will).

This is all in the idea stage at the moment...but it is the goal.
I do not plan on pulling down the engine (melted pistons) until around JANUARY because of this messed up year we are all dealing with.

So at the moment... no pics. Just talk.

Below is a pic of someone else's car... but it is a pic the wife sent me , to show what she would like..

66-2.jpg

I sent her back a pic of what she could expect below ( again, not our car)

IMG_0940.JPG

So what are your opinions :

Should I keep the motor the same and just write another tune...

Or should I lower compression and change the cam profile, which would lower hp/ tq all together.

Would like to hear the reasoning behind your opinions..
 
If unlimited funds just build what she wants-(1st picture). But practicality and age I personally would build Pro street with comfort--you would not regret that with less head aches including break downs.

Safety FIRST--dependability second--comfort third--looks last.
 
if youll run e85 the need to lower the compression is not there, but you certainly would need a lower boost to maybe 6 psi and ideally use a different and milder cam, in the street application
yes it will cut power significantly but boost durability also
 
Thanks T..
Funds are not unlimited ..... The only reason I spec'ed that price range is because ... It would take me much longer to complete the project and
have the same amount invested, if I do it myself...
Yes , I am 57 years old... I would like for us to attend cars shows and do a weekend drive here and there while we still are young enough to
enjoy it.
It really only makes sense to start with something already done, then customize it to our taste's.

This Covid thing has really put a damper on anything for the moment.. I have been reduced to 32 hours a week this year and don't expect
to see a 40 hour check until maybe November. The Company lost about $10,000,000 in contracts back in March, because of customers pulling the plug on
their new programs.. It's in survival mode here at the plant this year.
The wife and I are fortunate enough to have had enough common sense to put money away for a rainy day and retirement... and luckily for
me...she had enough sense to put a password only she knows on it!!
That's why I haven't started to rebuild the race motor ...and don't plan to until we get through this messed up year.
But... It makes for a good time to reflect and plan for future events and goals.

I was hoping I would hear something about de-tuning to motor.... My thoughts are it would make more heat if I pull back timing.. which we all
would like to avoid..
Now, I may not have to if I can lower the boost to around 4-5 lbs...I mean, for the most part the blower will mainly be for looks, and only occassionaly
be taken to the upper end.

The duration on the cam also may be too large for a street car.. Which opens up another set of problems...
 
Grumpy said:
if youll run e85 the need to lower the compression is not there, but you certainly would need a lower boost and a different cam, in the street application
Click to expand...

Now we're talking!
Without specifing an actual number....... I was thinking a street car cam duration would be somewhere around 230/240 area.

I don't need 800 hp on a streeet car.
I would think a 500-600 hp motor would be MORE than enough in that particular car to go out and have fun with.

I think larger duration cams make a street car "doggie" from the stop light. They are meant for higher rpm's.
My thinking is this car will mainly operate around 1800-3500 rpm's for cruising. But it would be nice to have enough cam to
have fun on a saturday night, with only changing the tune.
 
When I built my blown street motor I was advised to use 8:1 pistons. Never had a problem and drove it for 7 years I think and 100,000 miles. Blown street motors are awesome!
 
I understand the 8:1 pistons...But I have an abundance of
e-85 where we live and As we know....E85 loves compression.
Higher static compression would help the power levels
down low when the engine does not see boost.
 
8:1 static compession ratio,being suggested,is used for gas and a super charger\
that still uses high test gas, NOT e85

E85 could get by rather nicely with the 11:1 static compression ,
and a couple of pounds of boost
from a supercharger,
Id set the cam index split overlap as the cam is designed for nitrous and/or super chargers,
keep in mind the 8:1 boost referenced info on the cam card concerns GASOLINE not :rolleyes:E85 use:D

"E85 is roughly 105 octane using R+M/2. The ethanol content varies seasonally though since the low temp combustability of E85 is not as good as gasoline. It can be hard to start when it's cold outside so they add more gasoline to it in the winter. The more ethanol content the higher the octane rating, with Rocket brand being advertised at 112. In addition to the octane rating, E85 has a evaporative cooling effect that is much greater than gasoline which further contributes to its detonation resistance."
Click to expand...

Id use Something rather similar to
a crane 119661 hydraulic roller cam
that I've used for decades ,
should match that intended combo rather well.
crane119661.png

read this
https://www.onallcylinders.com/2015...-is-safe-effective-compression-ratio-for-e85/
 
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If you’re willing to travel to Kalamazoo or Kellogg, I know of 2 ‘66 Chevelles , one is a roller, the other a ‘66 that came from that Chevy dealership Auction in Nebraska a few years ago. A clean and straight 6 cyl, base model- absolutely no options except for trunk liners. I’m just throwing this out as FYI, My aunt has a really nice Malibu 1967 Chevelle left to her by her neighbor last October. It’s been offered to me but my plate is full and it’s low on my bucket list of cars. It’s in Marquette, MI email me for details
 
Btw, when I used to go to the Mecum auctions I used my little voice recorder to gather info on collectors and shops For cars there across the country. My thoughts were to join another guy and partner to become auto brokers. I still retain a pretty good data base to draw upon for car searches and I emailed all over the years.
 
Not yet Rick.... But YES we will be doing another one this winter.
The cam Grumpy suggested in in the ballpark of where I
thought I should start with.

I was thinking about using the solid rollers
I purchased last year..

chromebumpers said:
My aunt has a really nice Malibu 1967 Chevelle left to her by her neighbor last October. It’s been offered to me but my plate is full and it’s low on my bucket list of cars. It’s in Marquette, MI email me for details
Click to expand...

The wife is adamant on a 1966 only...
But I am not ready to buy anything yet,
I am just putting a plan in place ...
like I did with the truck...

Main focus is rebuilding the engine this winter,
with the intent of using it as a street engine.
 
I pulled the heads on my race motor tonight.
I was very surprised at what I discovered.

The cylinders had NO scratches in them!!!
The pistons are toast... but the engine turns over very smooth.

The heads look great with no damage.

This got me thinking about that broken rotor in the replacement motor....
I am suspecting that the rotor had broke in this motor also
and caused it to fail...before the pistons totally failed.

I have some pics of the inspection for you guy's..

IMG_1151.JPG IMG_1153.JPG
 
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