87 Couger 302 block verses 5.0 HO

Topic: 87 Couger 302 block verses 5.0 HO (Read 1770 times) previous topic - next topic

87 Couger 302 block verses 5.0 HO

April 19, 2007, 09:31:15 PM

Hey guys, I was wondering. A stock 302 in a 87 cougar is it the same as a 86-93 roller block? I am getting ready to give the old cat some new teeth. I am trying to figure out if my block would work or am I missing something. I keep on seeing roller blocks and tappet blocks. I have a powerdyne supercharger and some alum gt 40 heads and a E303 cam waiting to go to work along with 30 lb injectors and a Performer intake. I am just wondering about the stock block in the car is it a roller and what pistons are in it. Thank You :hick:

87 Couger 302 block verses 5.0 HO

Reply #1 – April 19, 2007, 10:19:15 PM

It is a roller block with a roller cam. The pistons are cast aluminum flat-top pistons (no valve reliefs like the forged HO units). You'll want to replace those pistons with that Powerdyne...

87 Couger 302 block verses 5.0 HO

Reply #2 – April 19, 2007, 11:04:19 PM

Block,crank,and rods are all the same parts numbers as an HO.
Only differances are pistons,cam shaft and timing chain.

87 Couger 302 block verses 5.0 HO

Reply #3 – April 19, 2007, 11:44:49 PM

If it's a 6 PSI Powerdyne, I'd run it on SO pistons. I'd make sure to get a bypass valve for it first. The 9 pound kits came with one standard. The six pounders did not. The bypass valve will extend the life of the kevlar belt inside the housing tremendously!

Read more here: http://www.foxtbirdcougarforums.com/showthread.php?t=2028

As I've stated before:

Quote

If you decide upon the 6 PSI kit as I have be forewarned it does not come with a bypass valve. I would highly recommend ordering it! In my searching the internet it seems the Problems with these kits stem from 2 things:
1) Overspinning the internal bearings by using an interbuttstuff pulley that is too small
(putting one in yourself to achieve say 13 PSI from a 9 PSI kit without upgrading the bearings)
2) Not using a bypass valve

A 6PSI or 9PSI kit will last a lot longer with the bypass valve. This ensures the backside of the impeller does not get boost kicked back into it thus shredding the internal belt. 9PSI kits have the bypass valve standard 6 PSI do not. Order it if you go with the 6.

I also assume with the E-cam, you ARE doing a Mass Air Swap, correct? Those alphabet cams have low vacuum at idle and run like poo with SD.

Those pistons may be even more of an issue with the GT-40's AND the E-cam. I'm not sure on the PTV clearance, That needs checking before anything else.

87 Couger 302 block verses 5.0 HO

Reply #4 – April 19, 2007, 11:55:13 PM

Wait, we have roller blocks? I thought we were tappet? Now I'm confused.....

87 Couger 302 block verses 5.0 HO

Reply #5 – April 20, 2007, 12:28:52 AM

As far as T-birds and Cougars go (at least in stock form)

5.0 with SEFI=roller block.
5.0 CFI/Carb =flat tappet.

87 Couger 302 block verses 5.0 HO

Reply #6 – April 22, 2007, 10:58:24 PM

I wouldn't waste my time trying to put gt-40y's or x's on any so short block. Although I didn't clay clearance test my gt-40 y's, I did bolt them an 88 so block with light valve springs and remember having like .008" clearance @ tdc and when I turned the motor I thought it bound up. It didn't seem to work for me even though a Ford dealer told me they would work with that year. The pistons were flat tops with NO reliefs. I ended up buying a 93 ho.
Here are some lessons that have caused me many headaches and expenses. Best thing I can say is do your homework.
93 HO motor have hyperpathetic pistons with reliefs. Avoid this year.
Trickflow heads will work with flat tops with no reliefs.
Gt-40 heads work only with stock type relief pistons.
Trickflow pistons work with Trickflow heads.
Trickflow pistons won't work with Gt-40 heads.
Bottom line is Trickflow heads are the ones to get. They are the most universal. Remember I learned this the hard way after spending a bunch on parts that won't work together. Even though it is my own fault, Ford and the aftermarket manufacturers should make this clear. Imo.
Good luck,
Mike

87 Couger 302 block verses 5.0 HO

Reply #7 – April 22, 2007, 11:30:30 PM

ALL 302 blocks after i think 85 are roller blocks.

87 Couger 302 block verses 5.0 HO

Reply #8 – April 23, 2007, 12:26:10 AM

What is the actual difference between a Roller and a non roller block. Block itself, ignoring pistons,rods, cam, lifters, etc.

I understand it's simply two threaded holes in the lifter valley to hold down the retaining bracket.

Is that info correct?

87 Couger 302 block verses 5.0 HO

Reply #9 – April 23, 2007, 12:29:58 AM

and the lifter bores are taller.

87 Couger 302 block verses 5.0 HO

Reply #10 – April 23, 2007, 07:58:58 AM

Quote

ALL 302 blocks after i think 85 are roller blocks.

Only the Mustang got the roller cam in '85. The '85 Cougar and bird block might be machined to accept a roller setup (much like the truck 5.0), I'm not sure.

87 Couger 302 block verses 5.0 HO

Reply #11 – April 24, 2007, 12:45:51 AM

Quote from: tireshredder;141466

Wait, we have roller blocks? I thought we were tappet? Now I'm confused.....

Yep just pulled my SO out. It was a roller.

87 Couger 302 block verses 5.0 HO

Reply #12 – April 24, 2007, 10:29:14 AM

Learn something new everyday!

87 Couger 302 block verses 5.0 HO

Reply #13 – April 24, 2007, 12:20:02 PM

Quote from: V8Demon;142246

Only the Mustang got the roller cam in '85. The '85 Cougar and bird block might be machined to accept a roller setup (much like the truck 5.0), I'm not sure.

So I take it my 83 motor is a flat tappet NOT machined for a roller cam?

87 Couger 302 block verses 5.0 HO

Reply #14 – April 24, 2007, 12:33:49 PM

correct, you can still use roller lifters, but you would need the $300+ retro-fit ones.