[Young Pontiac Guy]

I ran a 3.08 gear in the Bird, 400, 670 heads ported, summit 2802 cam. Talked to Cliff and it easily bled off the compression with the duration. Never had a problem with it running 93. Only ran race gas if I raced it. Qjet and dual plane factory intake. Pontiac torque made it a blast with the Richmond Doug Nash 5 speed. The 5 speed was the best thing I could have done because the >3.00 1st year in the Richmond trans made up for the gear too. It ran a 14 flat with a fuel pump that was not up to par and cut out at 5100rpm in second gear. And a blast on the street. Took it on a couple 3-4 hour trips and all over Ohio. No issues, about 14mpg, and a lot of fun on long cruises.

[Squidward]

Originally Posted by J.T.

Thank you so much for everyone’s help. I would still like peoples input. It will take some time to develop a plan to execute. This is what we have so far.
• I like the Idea of doing things a step at a time. Probably start with the gearing (step 1)
• I do have the original rear in the car so it looks like I will be looking at 3.36, unless I change the carrier. Car came with 3.55, that is long gone.
• Will consider the Voodoo 703 cam. Will still look at others. (step 2)
• Will consider duel plane intake, I have a ’72 #485912 in the garage and an adaptor for the Holley. No problem going back and forth from T2. (step3)
• Rear tires are 245/60/15 that are actuarially 26.6” (every little bit helps) I could look at taller tires after I smoke these. (step 4)
• The Rhodes lifters seem like they would help but not get me to where I want to be.
• I had the distributor worked on. I have 0*@800, 5*@1200, 10*@1600, 15*@2000, 20*@2600, 24*@ 3000, 8* vac, 12* initial = 44* all in.
• I can’t imagine changing to an automatic. I love the 4sp, maybe look at a 5sp someday.

I prefer a little more initial, 14-16, a little less mechanical, 20-22, and a little more vac advance, 12-ish, off manifold vac. As previously stated, it can help to soothe a beast at idle.

[Mister Pontiac]

Originally Posted by J.T.

Thank you so much for everyone’s help. I would still like peoples input. It will take some time to develop a plan to execute. This is what we have so far.
• I like the Idea of doing things a step at a time. Probably start with the gearing (step 1)
• I do have the original rear in the car so it looks like I will be looking at 3.36, unless I change the carrier. Car came with 3.55, that is long gone.
• Will consider the Voodoo 703 cam. Will still look at others. (step 2)
• Will consider duel plane intake, I have a ’72 #485912 in the garage and an adaptor for the Holley. No problem going back and forth from T2. (step3)
• Rear tires are 245/60/15 that are actuarially 26.6” (every little bit helps) I could look at taller tires after I smoke these. (step 4)
• The Rhodes lifters seem like they would help but not get me to where I want to be.
• I had the distributor worked on. I have 0*@800, 5*@1200, 10*@1600, 15*@2000, 20*@2600, 24*@ 3000, 8* vac, 12* initial = 44* all in.
• I can’t imagine changing to an automatic. I love the 4sp, maybe look at a 5sp someday.

Sounds like a great approach, JT. One step at a time.

I think even before you make the first change (rear gears), I would answer two other questions...

1. What type of driving do I plan to do most of the time? More Highway, or more City?
2. Will I take the plunge for an OD trans someday, or is that unrealistic?

These decisions will help determine what gears to switch to (your step 1).

Hope that helps.

[Half-Inch Stud]

Okay, good to hear you are cetain about the clutch & stick.

I agree thar the HEI tune is a great idea for dramatic fun improvement

[J.T.]

Originally Posted by Mister Pontiac

1. What type of driving do I plan to do most of the time? More Highway, or more City?
2. Will I take the plunge for an OD trans someday, or is that unrealistic

1. I would be doing more city/rural driving. 25-40 MPH. But would like to go an hour on the highway a few times a year.
2. In all likelihood the OD would not happen.

[Goatracer1]

Changing the 4sp to a 5 or 6 speed gives you all the benefits without the drawbacks.

[amcmike]

Originally Posted by J.T.

As a starting point I am looking at
• Lunati 10510702 262/268 deration 468/489 lift
• Performer RPM intake
• 3.08 gear
What would be the winning combination?
Thanks in advance for any help.

I like the choice of cam, and that with the rpm intake are a great step in the right direction. Run it with 1.65 ratio rockers. The 3.08 might be a little too low, better off with the 3.36.

[Young Pontiac Guy]

What about simply swapping to an overdrive transmission such as the Magnum or the higher gear overdrive (lower numerical)? Wouldn’t that solve a lot of issues and provide you with the Cruise ability you want? Won’t have to change out that rear gear. Would maybe be just a cam swap and trans swap. Just a thought.

[92GA]

Originally Posted by Squidward

I prefer a little more initial, 14-16, a little less mechanical, 20-22, and a little more vac advance, 12-ish, off manifold vac. As previously stated, it can help to soothe a beast at idle.

I agree. I'm running 10.5 compression on my 77 TA, .030 over 400 with 16 heads, performer intake. Don't remember what cam I put in it for sure but it was a Comp Cams cam. I'm running a th350 and 3.08 gears and the car was very lazy untill I bumped up the initial timing to 14 at about 800 rpm. I did have to limit the total using a crane cams limiter to keep it from spark knocking running down the road. Always have to use premium fuel too. I haven't driven the car in about 5 years, but I'm giving it to my son, and he will be driving it come spring. If I had it to do over I'd use a very mild cam, I'm an old man now and don't enjoy having to work on them all the time anymore.

[#1965GTO]

I switched to a Lunati Voodoo cam in my 400 and it works great. I contacted Lunati and with my combination their recommendation was the 701LK. That cam specs are 256/262 and.455/.468.. It yields a 1000 -5300 rpm range which is plenty with cast crank and rods.
My car is a 65 with 3.55 rear gear on an Eaton posi carrier and 200-4r trans. with 26" tall tire in 3rd gear,1 to 1 and locked converter, it's running 3400 rpm at 70 mph.
With your 4 speed car I would probably go with the 3.36 gear and like others recommend a 28" tall tire. Mine has a performer with 650 carb to match. As usual you are probably at least one carb size over sized.
Good Luck

[unruhjonny]

granted I didn't sleep at a holiday in last night;

My two cents;
Factory intake
Period Quadrajet
'744 cam
3.55 gearing

Then again, I like limiting one's self to factory stuff... and the '744 cam is arguably the best sounding one of them all.
With those heads, I wouldn't make the mistake of going to too small of a cam, that could cause issues fast.

[92GA]

I went out and looked at what I have in my engine. I have the XE268 Comp cam. It was very lazy until I bumped the initial timing up, with a 3.08 gear. It'll run with the 4th gen TAs and Camaros, have out run a few of them.

[unruhjonny]

/\ nice point;
I had my car in a a previous configuration beat many a fourth gen;
400; 0.010 over
#12 heads
067 cam (yup, you read that right)
M22 transmission
3.55:1 posi
"leaky" '71 Quadrajet

[Gary H]

Originally Posted by Goatracer1

Changing the 4sp to a 5 or 6 speed gives you all the benefits without the drawbacks.

Agree with goatracer. That's what I would do, change the transmission to a overdrive and leave everything else alone.

[79firebird_99TA]

Originally Posted by Sprocket

I am no expert but I did sleep in a Holiday Inn last night.

Props for not sleeping in a Motel 6.

I'm partial to my combo, but I really like the XE268 in my 400. It's choppy at idle and with the 3.08/4 speed there is nothing lazy about it around town or on the highway. At 80MPH, she spins at 3,000 RPM and my tires are 26".

Good luck.

[wovenweb]

Whew, I thought he was going to say he was puttin Chebby in it.

[leeklm]

As mentioned by others, I like a gear ratio in the neighborhood of 3.31 or higher when running a 4spd, assuming a ~2.41 first gear. If you had the 2.56 1st gear, a 3.23 rear would be ok.

While some people don't mind feathering the clutch from a dead stop (due to a low number gear), I personally hate it. My last 4spd car had a 27" tire, 2.41 first gear and 3.31 rear. I would personally not go any lower RPM than that if you are spending a lot of time with low speed city driving.

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