New Obsession...V2
 

Well, since my original thread went missing when PY was getting hacked this past summer, I decided to start a new version (V2.0) of it, but without all the history. Long story short, I bought a nice'70 Tempest 2-dr post coupe last December from Florida and immediately set out to tearing the 462/TH400 and interior to 'fix' a few things. I always wanted to build a '70 Tempest post coupe Pure Stocker with the XV code 400 4-bbl with the small valve 10.0 to 1 #16 heads just to see what it could do. The TH400 is freshly rebuilt to HD specs with a Continental 13" convertor and a 3.42 geared 12-bolt rear end. Not the best for the 1/4 mile, but a good compromise gear since I'm going to drive it more on the street.

The new 400 motor is based on a F240 YS block, D160/E200 heads, and a B190 intake with a 7040264 Q-jet and log exhaust manifolds. The heads were rebuilt with new Ferrea 6000/6001 valves, Comp 990 springs, 10 deg retainers and std. valve job (no back cutting the valve head, etc.) and cc'd at 78.0 cc's average (+/- 0.5 cc) after a clean-up cut (80 cc original factory). The block was bored .030" over and the crank cut .010/.010, new RPM 4340 I-beam forged connecting rods and forged Icon 2618 pistons with 2-1/16", 1-3/16" rings (full floating). The mains were machined for .0024" clearance and the rods .0021". The block will be assembled in the near future and we're thinking the actual static compression ratio will be close to 9.75 to 1 with .040" quench. A Summit 2800 cam (204/214/112 at .422"/.444") & lifter kit is planned to replace the 066 factory piece. The exhaust will include the Pypes 2.5" mandrel headpipes for log manifolds (no X-pipe...gasp!) and Dynomax Ultraflows (18" case) and 2.5" tailpipes. We will dyno the motor late October hopefully and should see 350 hp and 450 lbft torque.

More to come! Dennis

The Tempest....

Dennis

Love the pics! Sleeper right there!

Thanks Indymanjoe! The previous owner ran a couple of 11.90's at 113/114 mph in the summer Florida heat on G70-14 Wide Ovals.

Dennis

Thanks for re-posting V2.

Your car looks awesome! The photo is saved in my "I wish mine looked like this" folder...

Hope the engine goes the way you want it. Very cool to see a Tempest with this kind of vision for it.

Thanks Shiny! I believe you helped me with the front bench seat saga with the seat belt passage to the floor connection. I'm glad that was solved and I can focus my attention on the motor and getting it running and driving again (next spring most likely - unfortunately).

Dennis

Very nice car. Is that Palissade Green? Looks like Springfield Green from '72. One of my car was born this color. Not a big fan, but it looks awesome on your car with the steel wheels!

Think I was following the 1st thread, subscribing regardless, like the project!


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MescaBug...Yes, it is a slightly brighter version of Palisade Green (the original color). Believe it, or not, the factory listed dark green (Pepper green) for the steel wheel color when no full wheel discs were ordered. I think matching the body color looks best, but I may paint another set Pepper just for yucks.

Dennis

HWYSTR455...I recall that you took a picture of the dealership the car was ordered/sold at in Ashland, VA (Cardinal Pontiac-Buick on Rt-1?).

Dennis

No kiddin. I wonder why they didnt paint match the car/wheels. Pepper green is a lot darker than Palissade... Black would've been a better choice IMO, instead of different shades of green... :confused::confused:

Can you imagine pepper green wheels on a Verdoro green car? They called Verdoro a medium color and pepper dark.

Dennis

Dennis;

I am curious, since you're doing a "stock" rebuild, why the camshaft that would make it illegal to run in the PSMCD?

I too was following the old thread - and didn't realize it went away after hte last time this site was down... so re-subscribed!

Jonny, We found it very hard to police cams at the race, so we use the 16 in. vacuum at 1200 rpm the rule to adhere to. We also found that the cams that produce good vacuum, even very tame ones can go quick. I have the 2800 on the shelf and want to use it. The Desktop dyno said it made a whopping 5 hp and ftlb more than the 066. The 066 is a good cam at 200/211...so very close.

Dennis

/\ fair enough.

Thanks for humoring my (quite probably annoying) query.

I'm pretty sure I mentioned it in the "lost" thread", but it bears repeating, I really prefer the 70-tempest front bumper treatment over the 71/72 treatment.

No, not at all. Always glad to help Jonny.

Dennis

Our original PSMCDR cam rule of 1%/2% deviation on .050 duration/lobe lift isn't practical to enforce or police at the race when so much is going on. It is easier to attach a good vacuum gauge to the motors and see what they do at 1200 rpm in neutral. Exceptionally quick cars do get the once-over really good with a P&G (measures cubes), Whistler (measures compression ratio), and durometer check of the tires. We will yank a valve cover to see if roller rockers are present and also check torque convertor stall if its an automatic.

It's interesting that guys have found out that high(er) stall convertors hinder good et's on street tires and repro wide ovals. It's too easy to blow the tires off and be consistent, so tight (stock) convertors are the needed to kill too much low end torque.

Dennis

That car looks awesome, Dennis! The plain wheel with those tires is a fantastic combo. Reminds me of the T-37 Tom Miller and his dad finished a number of years ago. He ended up selling it to someone on this board (wish it was me!).

Vince

Dennis, your '70 looks good. Personally believe the pepper green steel wheels will give it a little contrast & really give a good look From the assembly plants, seldom did '70-72 Pontiac A-body's with poverty caps have same color wheels as body color, too many times the matching color steel wheels look contrived. Dave Hall has a 72 LeMans Coupe on eBay right now. Monarch Yellow with same color wheels & poverty caps...just does not look right.

Thanks Roger & Vince!

Here is the short block assembled and the pistons are all around .001" in the hole, which means we can use the Felpro 1016 head gasket with .039" crush to make our .040" quench goal and keep the compression around 9.75 to 1 to run on pump premium (93 octane in our area).

Dennis