[adams81267]

Not sure which cam was used in 1973 455 later model with TCS version 2. I just do not know which cam I have. The heads are 4X-H with screw in studs. It would be no cam change. Just changing rocker ratio. Understood about the pushrod holes. I agree with the mention of the Q-jet being standard as being sufficient. The carb is very universal with little or no modification.
After typing this I came back to edit after finding this link. Suppose it answers most of my question.
http://www.dapa.org/drag-racing-with...rocker-ratios/

Originally Posted by lust4speed

Adams81267, the critical point installing 1.65 rockers is the pushrod holes have to be enlarged (egg shaped would be a better term) or the pushrods will contact the head. Whether stock springs will work without coil bind, and valve seals survive without being pounded is another concern and also depends on the cam chosen.

Bulletpruf, going to a looser converter isn't all about performance, it is also needed with a larger cam. A stock converter is going to pull the engine RPM down and fight you at stop lights - which takes a lot of the fun out of cruising around.

The 96 heads actually start out at about 103cc's, and after a mild cleanup mill will usually still come in about 101cc's. So much for the reported 96cc's you find in print. You never know how many times a set of heads have been surfaced, so the only thing to do is cc every head. I wouldn't take any extra off sets of 96, 6X or 4X heads for a street build if they came in at 101cc or below. You will never feel the difference in power by milling them down, but you could end up listening to the pinging.

I agree with Cliff and Bart. Only thing I would probably save money on is by not searching out an 800cfm carb. I would think that the standard Quadrajet will be all that's needed for your RPM range. Cliff is the final word on that though. I had an 800 Holley spread bore double pumper on my street/strip car for years. Never one problem with it. I came across a very clean 780 Quadrajet so I threw it on the car next time out at the strip. The car ran over a tenth quicker, and the gas mileage improved. I had squeezed everything out of that Holley over the years and had the jetting down to a science, and sparkplugs were textbook. The Quadrajet was just bolted on and ran the way I bought it. Seat of the pants said the Holley was superior, the clocks and my wallet said otherwise.

[Cliff R]

"Cliff. Since ill never be racing seriously iv'e been considering this exact build since i already have 75% of the parts. I have a few questions about it...

1. Will it run power brakes?

2. Would it have any trouble running A/C or P/S?

3. How well would it work with an OD 5 speed and 3.73 gears?"

Fine with power brakes and A/C, vacuum at idle around 11-12". The combo I mentioned has a very broad power curve, with a lot of upper mid-range and top end charge, so it will like the stick shift and 3.73's gearing as well.....Cliff

[bulletpruf]

Originally Posted by lust4speed

Bulletpruf, going to a looser converter isn't all about performance, it is also needed with a larger cam. A stock converter is going to pull the engine RPM down and fight you at stop lights - which takes a lot of the fun out of cruising around.

The 96 heads actually start out at about 103cc's, and after a mild cleanup mill will usually still come in about 101cc's. So much for the reported 96cc's you find in print. You never know how many times a set of heads have been surfaced, so the only thing to do is cc every head. I wouldn't take any extra off sets of 96, 6X or 4X heads for a street build if they came in at 101cc or below. You will never feel the difference in power by milling them down, but you could end up listening to the pinging.

I agree with Cliff and Bart. Only thing I would probably save money on is by not searching out an 800cfm carb. I would think that the standard Quadrajet will be all that's needed for your RPM range. Cliff is the final word on that though. I had an 800 Holley spread bore double pumper on my street/strip car for years. Never one problem with it. I came across a very clean 780 Quadrajet so I threw it on the car next time out at the strip. The car ran over a tenth quicker, and the gas mileage improved. I had squeezed everything out of that Holley over the years and had the jetting down to a science, and sparkplugs were textbook. The Quadrajet was just bolted on and ran the way I bought it. Seat of the pants said the Holley was superior, the clocks and my wallet said otherwise.

Mick -

Good point on the converter. My experience with converters has either been with stock cams and converters or very large cams and very loose converters, so this is good info.

I got rid of the 96 heads; they were cracked. I now have a pair of 6x-4 heads. I'll probably pick them up from the machine shop so I can cc them and do some porting. They will go back aftewards for a valve job.

Interesting to hear on the Q-Jet vs Holley. I have an 800 Holley spreadbore on the shelf in the garage, but if a Q-Jet will get me more performance and better gas mileage, I'll have to see what I can find. Cliff did the 273 carb for my RAIV 70 GTO, so I'll have to see what he thinks.

Thanks

Scott

[Nicks67GTO]

Originally Posted by Cliff R

"Cliff. Since ill never be racing seriously iv'e been considering this exact build since i already have 75% of the parts. I have a few questions about it...

1. Will it run power brakes?

2. Would it have any trouble running A/C or P/S?

3. How well would it work with an OD 5 speed and 3.73 gears?"

Fine with power brakes and A/C, vacuum at idle around 11-12". The combo I mentioned has a very broad power curve, with a lot of upper mid-range and top end charge, so it will like the stick shift and 3.73's gearing as well.....Cliff

another quick question here....

I have a stock bottom end 455. It dosen't burn oil and keeps good oil pressure. Stock rods and rod bolts, with cast pistons. Would this bottom end hold up to this combo or would i be looking to put a picture window in the side of the block?

[bulletpruf]

Pistons and rods arrived - nice looking stuff! Will drop off a piston on Monday; shop likes to have the pistons there before they bore.

Need to ask BRC what the volume of the valve relief is, but I guess I could also use a syringe or something like that to cc them myself.

Also need to know what BRC recommends for piston/wall clearance.

Thanks

Scott

[tom s]

Glad they got there OK.Tom

[Skip Fix]

"Anyone measure the cc's on 6X-4 heads? I'm seeing 93 cc and 98 cc reported volume on a few websites."


My 6X-4s were virgin and measured 93. My 6X-8s from my original motor with a light clean up mill were 97.5cc.

[72blackbird]

Scott,
I just started my 455 build myself- initially I was considering just running Sealed power flattops and 5140 rods, but thinking about future upgrades made me decide to run Probe flattops, PPR 4340 A-beams, and ARP main studs. I'm planning to run a set of 6x-4's as well, and do the usual upgrades (porting, 2.11/1.77 stainless valves, pushrod hole elongation, etc.).

I got a polished Crosswind from a customer, so I'm going to port match the heads to run that and put my trusty Holley 750 v/s on and rejet for the new combo. After seeing how well PPR's TC-01 HF ran in a 455 I upgraded w/ 6s-7's, I'm gonna try the TC-02 HF in my 455. I also plan to run 1.65 roller rockers- I may run some 1.5 roller tips first and then swap over later to see if the full rollers make a difference.

Geno

[bulletpruf]

Originally Posted by Skip Fix

"Anyone measure the cc's on 6X-4 heads? I'm seeing 93 cc and 98 cc reported volume on a few websites."


My 6X-4s were virgin and measured 93. My 6X-8s from my original motor with a light clean up mill were 97.5cc.

Thanks, Skip. That's helpful.

Scott

[bulletpruf]

Originally Posted by 72blackbird

Scott,

I got a polished Crosswind from a customer, so I'm going to port match the heads to run that and put my trusty Holley 750 v/s on and rejet for the new combo. After seeing how well PPR's TC-01 HF ran in a 455 I upgraded w/ 6s-7's, I'm gonna try the TC-02 HF in my 455. I also plan to run 1.65 roller rockers- I may run some 1.5 roller tips first and then swap over later to see if the full rollers make a difference.

Geno

Geno -

Ok, what is a:

1. Crosswind
2. PPR's TC-01 HF
3. 6S-7's
4. TC-02 HF

I plan to try the stainless steel Crower full roller rockers. Probably 1.5 ratio.

Thanks!

Scott

[72blackbird]

Originally Posted by bulletpruf

Geno -

Ok, what is a:

1. Crosswind
2. PPR's TC-01 HF
3. 6S-7's
4. TC-02 HF

I plan to try the stainless steel Crower full roller rockers. Probably 1.5 ratio.

Thanks!

Scott

Sorry to throw too much Pontiac-speak at you.

A Crosswind is a hi-rise dual plane aluminum intake Professional products makes. I plan to put my 455 in my 72 Bird that has a shaker setup, so I'll have to get a dropped air-cleaner base to let me keep the shaker working.
http://www.pacificperformanceracing....manifolds.html

6s-7's are very similar to 6x-8 heads, but have provisions for an air pump- without the smog gear, and fitted with stainless 2.11/1.77 valves they have the potential to be very decent running heads.

PPR sells both the TC-01 HF and TC-02 HF flat tappet cams - they are made by Isky cams to PPR's specs. I was very happy with the results of the TC-01 in a mild 455, so with my slightly hotter 455 the TC-02 should be just as fun.

Geno

[bulletpruf]

Originally Posted by 72blackbird

Sorry to throw too much Pontiac-speak at you.

A Crosswind is a hi-rise dual plane aluminum intake Professional products makes. I plan to put my 455 in my 72 Bird that has a shaker setup, so I'll have to get a dropped air-cleaner base to let me keep the shaker working.
http://www.pacificperformanceracing....manifolds.html

6s-7's are very similar to 6x-8 heads, but have provisions for an air pump- without the smog gear, and fitted with stainless 2.11/1.77 valves they have the potential to be very decent running heads.

PPR sells both the TC-01 HF and TC-02 HF flat tappet cams - they are made by Isky cams to PPR's specs. I was very happy with the results of the TC-01 in a mild 455, so with my slightly hotter 455 the TC-02 should be just as fun.

Geno

Thanks, Geno. I speak Pontiac, but am more familiar with OEM stuff than I am with aftermarket.

Scott

[bulletpruf]

With 93 cc heads, 5 cc valve pockets in the pistons, .043 compressed thickness on the gasket, and pistons .010 in the hole, I'm getting 9.618:1 compression, which should be fine. I'll have to check the dynamic compression ratio just to make sure I won't have any issues with detonation.

Thanks

Scott

[bulletpruf]

Ok, so I checked the chamber size on the heads today. First one came in at 89 cc. Hmmm...that sounds low. I did two chambers just to be sure. Both were the same.

Next head was 93 cc.

The heads were not a matched pair; got them from a guy who had a BUNCH of them. Date codes are both 1977, so you think they would be the same. I did some un-scientifc measuring with a caliper on one of the head bolt bosses on both heads it looks like the 89 cc head was milled .010 or .020.

Looks like I'm in the market for another pair of heads.

FYI - picture of the head cc setup below - just have to level the head (helps if it's not entirely level; keep the air bubble under the area where you are filling), insert two valves (seal with grease if springs not installed), install spark plug, seal plexiglass onto deck with grease, then fill with colored fluid. I've used food coloring with a water/alcohol mix before, but this time, I used mouthwash (i.e., water/alcohol mix with color).

Scott

[bulletpruf]

Anyone have any recommendations on rings? Time to get rings and bearings ordered so I can get the rotating assembly balanced.

The BRC pistons take a 1/16, 1/16, 3/16 ring pack. Bore is 4.181.

Thanks

Scott

[bulletpruf]

Here's what I came up with - Total Seal Piston Rings CR3455-30 - Total Seal CR Classic Race Piston Rings - 1/16", 1/16", 3/16", standard tension oil ring, not file-fit. $114 for the set at Summit - http://www.summitracing.com/parts/TSR-CR3455-30/

This is a street motor; don't think I need anything real fancy here.

Thanks

Scott

[72blackbird]

So much for a budget 455 build-lol.

I was trying to be budget-minded too when it comes to heads, but considering how much local machine shops here in Socal charge to go through a set of iron heads, I think I may just find a way to get some aluminum heads on my 455 build. Screw it- I wanna go fast.

Geno

[Cliff R]

"I have a stock bottom end 455. It dosen't burn oil and keeps good oil pressure. Stock rods and rod bolts, with cast pistons. Would this bottom end hold up to this combo or would i be looking to put a picture window in the side of the block?"

Stock rods are always questionable in Pontiac engines. We've done fine with them here, but these days never use them for any power level.

I'd get a rev limiter and set it at 5800rpm's, and shift at 5500rpm's......Cliff

[Cliff R]

"Looks like I'm in the market for another pair of heads."

Did you find a matched pair yet? I may have one set of 455 #15 heads left, matched pair. They are an excellent choice for these builds, 87cc chambers, and virgin metal to set the larger valves in.....Cliff

[bulletpruf]

Originally Posted by 72blackbird

So much for a budget 455 build-lol.

I was trying to be budget-minded too when it comes to heads, but considering how much local machine shops here in Socal charge to go through a set of iron heads, I think I may just find a way to get some aluminum heads on my 455 build. Screw it- I wanna go fast.

Geno

A set of iron heads, complete, ported, new stainless valves, hardware, etc, will run me $1,400 (that includes the price of the cores). Aluminum heads will run several hundred $ more and the chambers are too small for my pistons.

Thanks

Scott