[BAD2000TA]

I am working on gathering parts to rebuild my 455. It's a YC block, .030 overbore, with #96 d port heads.

My plan is to upgrade to aluminum heads. For the longest time, I only wanted ported Edelbrock Performer RPM heads. But, as I'm gathering parts and researching, I've "heard" (internet rumor) that the Kaufmann Racing Heads are equal or of better design.

Is there a preference to either head? What are the advantages/disadvantages to each?

Next: Crankshaft. I currently have a factory 455 "N" crank. But, I'm considering going with a forged crank with 4.25" stroke and 2.20 rod journals. Again, any advantage/disadvantage going with the 4.25" stroke on my 455? Would keeping my current crankshaft and upgrading to h-beam rods/Ross pistons work fine?

Lastly, I currently have a standard Performer intake due to the Shaker clearance. I am running the Holley Sniper and plan to keep that. But, will a Torker II or RPM be the better choice? Meaning, yes, I know those intakes will make a huge difference in power compared to the standard Performer, but will having to use a drop-base air cleaner negate any performance gain of those intakes?

Thanks!!

[Skip Fix]

My 78 still has a massaged Shaker base with a T2. Tight but OK. Has run 10.90s with 2 different 455 with it and only a slight wedge spacer to get the angle an the Shaker perfect. Both motors used stock 455 cranks, but aftermarket rods and pistons.

It depends on if you have D port headers already. I have seen some guys make good power with D port KRE heads but I think a lot more work to get the same flow as the round port E heads. 2" headers a little easier on the round port motors.

[BAD2000TA]

Originally Posted by Skip Fix

My 78 still has a massaged Shaker base with a T2. Tight but OK. Has run 10.90s with 2 different 455 with it and only a slight wedge spacer to get the angle an the Shaker perfect. Both motors used stock 455 cranks, but aftermarket rods and pistons.

It depends on if you have D port headers already. I have seen some guys make good power with D port KRE heads but I think a lot more work to get the same flow as the round port E heads. 2" headers a little easier on the round port motors.

Thanks, Skip. Based on the consensus here, I think my plan will be ported E heads. As for intake, while I get that the factory intake can make good power, I have the Sniper which is a square bore flange. Utilizing a factory intake isn't really an option. I think that the Torquer II is probably the best option.

Thank to all that replied. I really appreciate the insight and advice!!!!

[Gach]

With a ported E-head 550 hp is very easy to make. I like you line up of cars, real nice variety.

[steve25]

The big question you need to answer for your own good is this.

How much HP do you want to make.

After this the next question is a A and B .
The A part of it you need to answer is how much hp do you think you need ?

The B section is how much is good drivability important to you.

Keep this in mind.

Your stock 96 castings along with Headers can make you a easy 390 hp with the Performer intake along with excellent idle and drivability.

As you step up in the level of intake air flow a head can provide your going to start a trade off process between drivability and top end HP.

Once you get to the point where you have a head on the motor that your not making full use of the intake air flow it can provide, then your really going to trade off idle quality, drivability under 3000 rpm and the level of HP you where looking to make will not be achieved either.

Most of the aftermarket heads even out of the box flow like 260 intake cfm@28” and should make you 500 HP while not effecting your drivability with even 455 cid, no less stroking it larger.

If you have never even driven a car with a motor making a solid 450 hp then don’t go over board paying for and installing parts to make 600 HP.

Don’t go over board with Flow numbers and or HP just to have short lived bragging rights!

[BAD2000TA]

Originally Posted by steve25

The big question you need to answer for your own good is this.

How much HP do you want to make.

After this the next question is a A and B .
The A part of it you need to answer is how much hp do you think you need ?

The B section is how much is good drivability important to you.

Keep this in mind.

Your stock 96 castings along with Headers can make you a easy 390 hp with the Performer intake along with excellent idle and drivability.

As you step up in the level of intake air flow a head can provide your going to start a trade off process between drivability and top end HP.

Once you get to the point where you have a head on the motor that your not making full use of the intake air flow it can provide, then your really going to trade off idle quality, drivability under 3000 rpm and the level of HP you where looking to make will not be achieved either.

Most of the aftermarket heads even out of the box flow like 260 intake cfm@28” and should make you 500 HP while not effecting your drivability with even 455 cid, no less stroking it larger.

If you have never even driven a car with a motor making a solid 450 hp then don’t go over board paying for and installing parts to make 600 HP.

Don’t go over board with Flow numbers and or HP just to have short lived bragging rights!

Yes, I have driven cars with over 450 horse. My 2001 Trans Am has a stroked LS6 that dyno'd at 500 rwhp and my daily ride is a 2022 Dodge Challenger Hellcat Widebody. I'm looking for roughly 535-550 horse, and 590ish in torque. I recently rebuilt the 10 bolt rear with a new Eaton carrier. 3.42 gears and Dutchman axles. The turbo 350 is going to be swapped for a t-56 next year as well.

[Singleton]

Originally Posted by BAD2000TA

Yes, I have driven cars with over 450 horse. My 2001 Trans Am has a stroked LS6 that dyno'd at 500 rwhp and my daily ride is a 2022 Dodge Challenger Hellcat Widebody. I'm looking for roughly 535-550 horse, and 590ish in torque.

Are you talking rear wheel or Flywheel numbers here when you say 535-550? I'm assuming rwhp from the context, so that would be approximately 650ish flywheel hp?

[Formulajones]

Originally Posted by BAD2000TA

I am working on gathering parts to rebuild my 455. It's a YC block, .030 overbore, with #96 d port heads.

My plan is to upgrade to aluminum heads. For the longest time, I only wanted ported Edelbrock Performer RPM heads. But, as I'm gathering parts and researching, I've "heard" (internet rumor) that the Kaufmann Racing Heads are equal or of better design.

Is there a preference to either head? What are the advantages/disadvantages to each?


Thanks!!

There are different camps on that subject. Kauffman makes a nice head but one of the things I noticed that I like about Edelbrock better (at least on the older ones I've had my hands on) is the use of helicoils in the threads. Thought that was a nice touch as most aluminum heads don't bother with that. This is rarely if ever mentioned. It's the small details

Either head would get you to a nice power level.

[grivera]

I have a set of Butler 290 cfm D port E heads shaved from 87 to 81cc in the bird. And on the shelf I have a set of 85cc KRE 310 D ports. Both have the heart shaped chamber design and folks on here have had great results with both. One thing I recall with a friend’s set of off the shelf KRE D-Ports is Paul Carter built the engine and said some of the threads for the rocker arms pulled out of the heads and he had to install heli-coils. It’s my understanding E-heads have steel thread inserts in all or most areas.

[grivera]

Of course Larry Tree’d me!

[Formulajones]

Originally Posted by grivera

Of course Larry Tree’d me!

LOL

[Formulajones]

Originally Posted by BAD2000TA

Lastly, I currently have a standard Performer intake due to the Shaker clearance. I am running the Holley Sniper and plan to keep that. But, will a Torker II or RPM be the better choice? Meaning, yes, I know those intakes will make a huge difference in power compared to the standard Performer, but will having to use a drop-base air cleaner negate any performance gain of those intakes?

Thanks!!

You'll find a lot of guys here agree on the opinion I'm about to explain. My choice on a Pontiac that needs to keep hood clearance, especially with shakers or Formulas with ram air, I prefer the stock iron or aluminum intakes.
Not only does that make fitting factory air cleaner parts a snap as everything goes together as it should, but they have no problem making HP. I've done 455's with stock intakes (455HO aluminum intakes in particular) make over 500hp without any work done to them. The factory intakes are simply a pretty good design from the start. And if you want to do the common modifications to them that's been done for decades, they have the ability to support even more HP.

[PunchT37]

Iv`e got my 455 with the factory crank, RPM I beam 4340 rods, and Ross piston. This thing goes to 6500 with my combo. No need to "stroke" to 4.25 IMO. It also keeps the piston pin out of the ring pack better with the 6.625 rod in a street app.


After that, I will leave it to the shaker guys to find the best combo for fitment. Cam, heads and intake, air cleaner, have to work together. So, you would have to put together a "shaker" package for your needs.

Your choices would be wider outside of the shaker system.

[Dragncar]

If you are going round port in a 2nd gen run the Edelbrocks just for hood clearance issues. Unless you are trying for big, big numbers in your bird you are better off with E heads.
They can do more than what you want without any issues.
The no heli coil thing was one of the reasons I went with shaft rockers on my High Ports. Spread the load out was my thinking.

[leeklm]

Good advice from Steve regarding goals. For ME, these old cars loose their luster when my 2019 4cyl Buick outperforms it in every category. I like a little raw HP and grunt!

Had a 400hp iron head 455 in my 66 GTO 4spd and got a little bored with it. I essentially bolted on a set of KRE 290 cfm d ports, bigger cam (stump puller) and factory iron intake with qjet. Estimated at 480 to 500hp, This combo completely transformed the car, making it a lot more fun to drive, even when cruising. The combo was mild enough to have great idle, decent exhaust tone, and run on pump gas. It was a home run in my book!

As far as dport vs o port, a lot of it depends on availability of manifolds or headers for your car. I have 325cfm d ports now, only because of header availability when I first built the 461 stroker 5 years ago. If I were to build a new engine today for the firebird, I would definitely go with o port for more flexibility and available 2" headers for this chasis.

These are the types of decisions needing to go into your evaluation process. Enjoy the journey!


Sent from my SM-G965U using Tapatalk

[Gach]

Question for you are…Edelbrock round ports out of the question for you. If not I have a nice 500 hp combo that sounds perfect for what I think your looking for.

[Gach]

One thing I want to mention when it comes to KRE heads, unless you plan on helicoils them don’t waste your money because The aluminum threads are prone to pulling out.
Even shaft rockers aren’t going to help not that you would or plan on shaft rockers.

[slowbird]

Originally Posted by Gach

One thing I want to mention when it comes to KRE heads, unless you plan on helicoils them don’t waste your money because The aluminum threads are prone to pulling out.
Even shaft rockers aren’t going to help not that you would or plan on shaft rockers.

Really? You have personal experience with this?
I ran 1100lbs open 500lbs on seat 9000rpm with zero issues. I think your info is exaggerated.

[Stan Weiss]

Originally Posted by slowbird

Really? You have personal experience with this?
I ran 1100lbs open 500lbs on seat 9000rpm with zero issues. I think your info is exaggerated.

Brian,
You try different things to see what works. That can be expensive, but it puts you out front. While some people just follow along with what other people tell them works.

Stan

[Skip Fix]

An HO intake on any kind of ported Eheads is a cork even if the intake is ported compared to a T2 I ran one at first because I did not want to "massage" my original base for a Holley. Found a used base -dimpled the front for the bowl adjusting screw grafted in a section from a cheap drop base for the rear one.