71' 455 New Heads/New Cam

Hey everyone!
I don't post much but when I do I ask for advice and tips to help me build up my BBB. You guys are very helpful and I deeply Appreciate your advice. So for news, I recently saved up enough money to go down to TA Performance and do some shopping, with all the tips you guys gave me I put my money to use. I went TA all the way, I have invested in to a set of Stage 1 Street Eliminator Aluminum Heads (Fully Assembled), and a 290-94H Cam with Tappets and Pushrods. Tim from TA was a big help into seeing what my motor will become and seeing which parts will work well with each-other He said that my 8.5:1 CR will turn into just about 9.25:1 CR and also said that since the cam will work perfectly because it only requires 9.0:1 CR and that the setup that I am overtaking I will not need a new stall converter. I just wanted some tips and advice when I install these parts and maybe some fun guessing on how fast my car is actually going to be. So Ill give you all the info you may need to know.

-Stage 1 Street Eliminator Aluminum Heads (Fully Assembled)
-290-94H Cam with Tappets and Pushrods
-T400 Transmission
-B&M Shifter
-Ford 9" Rear
-Completely stripped car (No Trim, No Backseats, Almost Bare Bones)
-Edelbrock RPM 455 Intake
-Stock Wheels Sadly
-3 Core Aluminum Radiator

Go easy on me, I'm a rookie when it comes to cars! Hope you guys appreciate the work Im about to put down on this BBB! ray:

 

What rear gear are you running ?

 

Oh yes I forgot, I am running 3.50 GR

 

I'll throw up a WAG............450 HP at the crank as long as a good 2 1/2 in exhaust is used with headers.

 

Don't skimp on ignition. Either use an HEI or convert your old stock points to some form of electronic. Be sure you recurve it to get the most out of it and power tune it per Larry "The Wizards" recommendations.

What carb and what RPM are you planning to see? If you have a tuned 800 Quadrajet or an equally tuned 900+ Holley and spin it to a comfortable 5500-5800, I'd guess the low side of 500, probably 475-485 range. 1/4 mile speed of low 12s if you have traction problems and with some tuning high 11 passes are my guess.

 

Edelbrock doesn't have a "RPM" intake(I wish they did.) for a 455 but you probably mean B4B which will work fine. The cam you picked is a great all around performer.

Do you have an aftermarket converter in there? If you do not then plan on getting rid of it soon. The factory 13" T400 converter will be lucky if it has 1800 stall and it will feel like a pig off the line with good traction. Consider any camshaft manufacturer recommendations the bare minimum you need for the cam to work decently(including compression). If you have some sort of higher stall converter you'll be ok. If not I'd look into a 2500-3000 stall converter and the car will fly off the line.

I'd consider having the heads milled .030" to bump the compression up even more. Use adjustable pushrods to set the lifter preload correctly. You never said what shortblock you are setting the heads onto.

I agree with Greg on the performance potential when everything is set up right and the winds are blowing in your favor. The lighter the car the better.

 

I forgot to mention I have an HEI Distributor, I also failed to mention I am running it with a 750 CFM Holley. Do you really think I'll reach 12's if I have good traction? I would be the happiest guy in the world if that happens! ray:

 

Time from TA Performance said that the 290-94H Cam is perfect since I'll be at 9.25:1 Compression right after the head upgrade and he also said the stall converter will be just fine. He claimed that's the best cam to get with my setup. I really should invest in a converter but since I just nearly spent 3k on heads and cam etc. I do not have that kind of money. I also left out that my valves are 11/32 in the new heads. And I'm really new to this, what do you mean I never said what shortblock I'm setting the heads into, I'm putting the heads on my 455 71' Riviera Engine, the one that's in my Skylark.

 

Can you use the .020 steel shim headgaskets with eddy heads?? they will give you a lil more compression. which can only help. Check with TA on this.

 

I assume your wanting to build a track toy seeing how its not full interior and no amenities, and if you are interested in it running strong you need a converter dont have to be some $1000 piece, $380 will get you a quality unit that will vastly improve acceleration over stock. Also if track performance is the goal ditch the Edelbrock and get an SP1 or even a SPX so you'll be ready for the future, if you wanna stick with the Edelbrock put a spacer to help improve plenum volume. And the 750 Holley will probably be fine but I myself would use no less than a 4781 850 Holley. If you have a Vacuum Secondary get rid of that thing

 

I'll make a guess 455hp. I'm a;ways happy when Tim answers the phone. good guy and knows what combinations work.

 

Ill make sure to ask them! Thanks!

 

Yes and No, I am building more of a street based sleeper. The car itself doesn't look worth more than 2k, but there is no absolute rust and the car runs perfect. I will definitely look into the SP1/SPX I heard many good things about them. Also friends and owners say to go Edelbrock 750 and stay there. They gave me the advice that it is a very good midrange Carb, so I'm going to ask TA to see what Carb I should run. Thanks for the advice tho!

 

My advice is stay away from the Edelbrock carbs , I wouldn't run one if it was given to me. If anything due to the fact they have got to be the dorkiest looking carb ever made,..jmo tho, them things are popular with the chevy and ford crowd for a reason

 

I'm sure Tim is very knowledgeable in Buicks but you did come on here and ask for tips and advice. As I said I too think the cam you've chosen is a good cam. I'm sure it will work "just fine" as you've outlined. However, if my girlfriend said to me "That was just fine." I'd start to get nervous. Since you've said you're new to the HP world I only offered what I would consider a few easy things to do to make your combo better than "just fine".

I can fully understand the idea that you can't afford everything at once so you have to buy what you can as you can. The good news is a torque converter can easily be installed later. If you are never going to take it to the strip or install sticky tires than you may never need a higher stall converter. However, if you take it to the strip with good tires on the back you'll understand quickly how slow (I'm assuming here since you never really clarified what you have.) a stock '71 Riviera 13" T400 low stall speed converter can feel coming off the line. Maybe you can ask Tim if the car would be quicker at the strip with a higher stall converter than the factory one which is "just fine". Heck, a completely factory stock G455 with good tires would be quicker with a higher stall converter and that is with the smaller factory camshaft which will make better low end torque.

From your shortblock description I'm taking it that it is an untouched from the factory shortblock. Ask Tim if higher compression would make the cam work even better? I've run 10.4:1 with the same cam(with iron heads) made by Scott Brown and I can tell you it ran better than just fine. Ask Tim if he used a deck height of .040" to come up with the 9.25 compression ratio. If he did then know this, unless the engine was rebuilt sometime in its' past and the deck machined, that .040" would be your absolute best height and that it more than likely will be approaching .050" which will lower compression to 9.1:1. Ask him if the heads have 62 CC chambers. If they milled them to get 62 CC then fine. If not then request that they do it because that is what it will take for you to get 9.25:1. Anything larger and you will have less compression. Because aluminum heads dissipate heat quicker than cast iron heads(and heat being given off to the air is lost HP in the cylinder) generally speaking when you install them you want to increase cylinder pressure just to stay even as far as performance is concerned. Anywhere between 1/2 to 1 full point of compression is needed just to stay even with the lower compression iron headed engine. In your case the compression increase has made up for the lower cylinder pressure because of the camshaft duration increase but not for the head material change. Now don't panic because the change of cam and much improved cylinder head flow will more than make up for the loss through. In the range of compression you are in extra compression never hurts.

I'm not sure about using the thinner uncoated .020" steel head gaskets with the aluminum heads but thinner head gaskets would help if your heads have already been milled to get 62 CC. TA does sell .027" Multi-Layer Steel head gaskets which I'm sure will work because they are coated. That would be worth about .25 in compression compared to the standard .040" gaskets. A bit pricey for the gaskets but would you rather do it right now or later? All I'm saying is that now is the time to do the things that will help performance, not later.

The thread below is sort of a worst case but it illustrates what happens when you lose cylinder pressure, as in not enough compression and too much cam. Your cam is actually bigger than his so even with the same compression your cylinder pressure will be less. Again I don't consider these "big" cams but without attending compression increases low end torque suffers. You do have the advantage of lighter car and better gears so the low end loss won't be as noticeable. Forget about the "miss" part and read #31 first and then go back and read the whole thread about what he wants to do to the engine:

http://www.v8buick.com/showthread.php?249150-My-455-backfires-when-accelerating-hard/page2

Assuming your '71 455 is an untouched factory stocker before the camshaft goes in I'd do a careful examination of the #1 cam bearing. They can wear and cause lower oil pressure. The other ones usually don't wear badly but should be examined when the cam is going in. I'd also look into rebuilding the oil pump with a TA thrust plate and gasket shim kit correctly installed.

Edelbrock intake, OK. If the Holley 750 you have is a double pumper you are OK. X2 if the Holley is a vacuum secondary get rid of it but not for an Edelbrock carb. X2 on a spacer on the Edelbrock intake.

Your car will work fine if you do nothing else to it than you have planned and you'll pick up a ton of performance. However, I said it in an earlier post and I'm going to stand by it: The camshaft manufacturers recommendations are the bare minimum you need to do to have a particular camshaft work OK in a car but they are not optimum.

 

I agree on the Eddy carb I rather use a well built 800 cfm Qjet as an edelbrock 750, 750 cfm isn't enough for a good breathing BBB

 

I appreciate your insight, although it did come off a little sarcastic to me. When every other sentence was quoted with "just fine". When I say that's what Tim said it was more of paraphrasing as in he said "The camshaft should have the minimum requirements to work in your motor for that compression". He said there are many things I can do to get more power out of what I have, but he said for your budget and time this will be a perfect way into getting shy off 100HP out of your motor. Again thanks for the advice, I will check up on everything about my motor. This post was more about advice on how to install, and what I am going to be pushing for HP. More of a fun talk about my new set is what I was going for. TA has helped me with advice on what to get, and they have gave me even more advice on the past few days.

 

The carb and intake advice you have received is good. SP1 or SPX intake would help you a bunch. The BBB likes the open plenum design.

On the carb, keep in mind the stock 455 came with an 800 cfm quadrajet. Your 750 won't give it all it needs, but would feel peppy. A good custom built 800 cfm quadrajet would be great for street and performance, or if I go Holley 4150 type, go 850 at least as mentioned above.

A nice convertor would also help.

Good luck and have fun!

 

There are several knowledgeable people on V8 BUuick that will give good solid advice based on their time and experience with BBBs. They are here to help and give info on there own time, and it's free. So even if it isn't sugar coated it is usually good info and should be appreciated, they don't have to give it. I don't know Mike but have read his posts over the years and can tell he knows what he's saying about Buicks. Good luck with yours.


Bob H.