Thread: Picked up some GT 40 P heads

Tweet

Think he's saying use less cam.... Think I'd try the one Jay made up for you. If it was right for the automatic, should work fine with the 5 speed.....

Originally Posted by Dave Severson

Think he's saying use less cam.... Think I'd try the one Jay made up for you. If it was right for the automatic, should work fine with the 5 speed.....

That's what Jay said. It's in there. I'm not going to change it unless it proves to be a problem. I'm sure it'll be quite different from the stock '69 302/2V that I ran in the car for years! Actually this is that same engine, just beefed up a little!

Originally Posted by DennyW

The only thing I see with going over your cam specs, is you will have 2= Over Drive gears... 4th gear for 45-50 mph, and 5th gear for 80+ mph...

Do you mean that with the 3.0 rear gears or the 3.50 rear gears?

Here are some calculations based on my 5th gear at .68:

R&P ratio 70mph 5th gear .68 RPMs
3.0 1714
3.50 1999
3.89 2222
4.11 2348

Since you said I'd have 2 overdrives, here are the numbers for 4th gear at 1.0:

R&Pratio 70mph 4th gear 1.0 RPMs
3.0 2520
3.50 2940
3.89 3268
4.11 3452



I may end up with a 29" tire which would change these numbers a little but not too much.

This chart didn't post the way I intended but I think you guys can figure it out. It's all figured at 70mph with the different rear gear ratios with a 28" tire. The same is applied to both 4th & 5th gear.

Originally Posted by randyr

Do you mean that with the 3.0 rear gears or the 3.50 rear gears?

Here are some calculations based on my 5th gear at .68:

R&P ratio 70mph 5th gear .68 RPMs
3.0 1714
3.50 1999
3.89 2222
4.11 2348

Since you said I'd have 2 overdrives, here are the numbers for 4th gear:

R&Pratio 70mph 4th gear 1.0 RPMs
3.0 2520
3.50 2940
3.89 3268
4.11 3452



I may end up with a 29" tire which would change these numbers a little but not too much.

This chart didn't post the way I intended but I think you guys can figure it out. It's all figured at 70mph with the different rear gear ratios with a 28" tire. The same is applied to both 4th & 5th gear.

looks like some good cruizin' rpm to me!!!! Had 4.56's in my '83 for awhile, with a 3 pedal 5 speed car it works just fine!!!! Heck, used to play on the street with the Mighty Mav with 6.50's on a spool with a Windsor and my trusty old Nash 5 speed!!!!! Absolutely the most fun you can have with yer clothes on!!!!!

Originally Posted by Dave Severson

looks like some good cruizin' rpm to me!!!! Had 4.56's in my '83 for awhile, with a 3 pedal 5 speed car it works just fine!!!! Heck, used to play on the street with the Mighty Mav with 6.50's on a spool with a Windsor and my trusty old Nash 5 speed!!!!! Absolutely the most fun you can have with yer clothes on!!!!!

Yeah, I don't know what rear gears I'll end up with yet. Depends on what kinda deals I find out there but while I want some performance on the low end, I want to at least have a shot at some ok mpg's when highway cruisin'.

Coffee ,donuts ,STEAK ,blonds with flat heads what ever you want . Even a real comfy bed with color tv and oh yeah it has a remote too . LOL

Originally Posted by randyr

Yeah, I don't know what rear gears I'll end up with yet. Depends on what kinda deals I find out there but while I want some performance on the low end, I want to at least have a shot at some ok mpg's when highway cruisin'.

Randy they say the 3.55 is a great gear with the T-5 trans . Performance and mileage . Now with the EFI it even gets higher but looks out of place under a 37 hood . But hey we could try it and see it for ourselfs right .

Originally Posted by bluestang67

Randy they say the 3.55 is a great gear with the T-5 trans . Performance and mileage . Now with the EFI it even gets higher but looks out of place under a 37 hood . But hey we could try it and see it for ourselfs right .

I've seen the EFI in a couple of them and it didn't look too bad to me! LOL! The only thing I think looks funky in a 37 is a V6! It just seems wrong though I'm sure some have done it! LOL!

Yes great stuff definitely going to talk to him once I figure out what the bottom end will be . If this block is a C9 neighbor said he see's it I haven't put my eye to it totally yet but it doe's look like it . Some cleaning and a little rust dabbing I will bring it out . . But should have 9.5 compression If it is a C9 .

These heads and that compression will make a great street engine , driveable with some performance .

Now I just need Dave here a few days to help me sheet metal it

Originally Posted by bluestang67

Now I just need Dave here a few days to help me sheet metal it

Well, the Plymouth will be on the rotissierie sometime this week, depending on how long it takes my crippled old body to get the tin work done.... I can be had, but I ain't no cheap date!!!!! Somebody has to furnish the coffee and donuts on house calls!!!!!