[1funride]

Ok if you had 4000 to spend and the goal was a really strong running street engine, what would you do? Stroker? SD ported heads? E heads, Roller cam? Etc Question left vague on to encourage options.

1968 Firebird
Block: 1967 WT (GTO) 9786133 (Stock)
Heads: 1968 #16 (Stock)
Exhaust: Doug's Headers, Flowmaster 80 Series 2 chamber cross flow Delta Flow muffler
Intake: Edelbrock Performer
Carb: Edelbrock Thunder AVS Carburetor 1813 800cfm
Ignition: MSG Pro Billet 12 to 37 by 2600rpm
Coil: Pentronix Can
Cam: Edelbrock Performer (204/214 110) (came with the car. understand the limitations)
Tranny: TH400
Rear: Built 8.5" 3.42

[NBF823]

First thing I would do is forged rods & pistons, good bolts and good machining holding it together. Won't make any more power, but it's gotta be done, and worth the peace of mind.

My next move, would probably be based on the remaining buget; I'd look to the cam, and see how far the buget would let me go with possible swaps to springs, torq verter, and gear. At that same point, which is more based on my style of driving - I would also consider keeping money off the cam for the time being and swapping to a 4-speed, loosing as much weight off of the front end(fiberglass), the weight and tread width of my wheel and tire package, possible suspension geometry changes(Guildstrand and Adams), and making the chassis as ridged as possible. Also a game changer; Got disc brakes in the front? Got a good seat that keeps you in the same spot with a head rest? And got at least a good 3-point belt?

[1funride]

Interesting recommendations. I like the idea or a tougher lower end, but with no more power, it doesn't seem necessary. I am hoping to build more power, and still have a reliable engine. The car is already equipped with a Hotchkis suspension system, big stabilizer bar, 17" rims, kyb shocks, and some sticky tires. It handles amazingly well. It runs out of steam really quickly right now, all done making power at low 4000 rpms. I want it to pull to 5000, and make more power. It is a bit disappointing as compared to my other brand cars.

[tom s]

JMHO,the weak link in our pontiac engines would be the rods.With the power level your looking at I would for sure get a set of good forged rods.Many pontiac shops can supply for around or under $300.More power with street maners will come from CI so a stroker kit would be on my list.THEN a cam tailored to your street driven RPMs.Without a doubt I would go with a hyd roller.There is a few things for you to chew on.Tom

[GTOLou]

stroked rotating assembly. I use HR cam's pretty much in every build - but if your on a budget it is expensive.


I'd get a cast eagle crank stroker kit w/ forged rods and pistons cc'ed for your heads. You can always upgrade to aluminum heads in the future. You'll need a new cam, the Ramair IV melling hydraulic is cheap and'll do well w/ the stroker. Only other issue would be the performer intake but you can change that down the road too.

Find a good machine shop to help w/ the shortblock.

[critter]

Port the heads and up the cam. I'm no fan of that brand of carb either but it should flow enough. The engine is an air pump. It needs more air. The RPM intake is a better choice but you'll have hood clearance problems. And lighter, better rods and pistons wouldn't hurt if you intend to spin it much beyond 6000 RPM. You mention headers and exhaust so I'm assuming it's 2.5 inch or better.

[1funride]

Is there a good knowledgable machine shop in the Binghamton NY region, or within a driving distance? I hadn't thought about just using the existing heads and using a dished piston. That would save a bunch of m

[1funride]

Sorry fat finger mistake. Using ported stock heads would save money. Is it possible to get the machine work done, put in a stroker kit, and port the heads for 4K? that assumes using a hft cam and my existing intake or Pontiac stocker.

[68blackbird]

are you going to race it? Is it a commuter car?

Cam
Stall Converter
Fuel system

When your car runs 12:00 with that 400 then go for the beefed up bottom end.

by the way... I just saved you $3000!!!!

Rich

[NBF823]

That clears up the chassis questions.

On the dished piston; I'd probably avoid it. If your just using the car once in a while, you'd just be fueling it the same way you do now. I favor long term reliability and potental on the bottom end as opposed to getting power or cheap gas now. If you go with a dish, what happens to the quench area and the flame travel, and how does that limit future things like aluminum heads or cam choices? I ran a 224/234 @ .050 on a 400, that motor lasted a while with a stock rods and bolts, but I'd probably still be hot dogging that motor now had I had a better bottom end. And you could also talk to someone about dynamic compression and the oct required - you may be killing two problems(power & fuel) that way, as opposed to creating potential problems for building power(inefficient combustion process). But on the other hand, with the stroker, your high cr 400 heads with more cu in under them, the compression is going to just jump outta useable range, and you'll not be able to use it till you get new heads. Hmmm...

Maybe some of the race section or engine builder guys will come over and help with fuel, cr, and your goals. I'm near the limit of my knowlege on these things.

[1funride]

My usage is not a commuter car, but also not a race car. I will drive it to work and on an occasion will take it a test and tune for fun. I guess I thought the dished pistons would work with my 72cc heads and later with a 72cc edelbrock. I see SD can port cast iron heads to around 240cfm. Seems like a stroker with cast crank, forged pistons and rods would be plenty durable. With a good HFT cam, is 450hp possible with this setup? Is there issues with using domed pistons to get CR down to an acceptable level?

[Pontirag]

always spend as much as you can on the bottom end.

that being said, I would also make the car safe to drive at increased speeds

[ta man]

Double your budget and build what you really want!

[grandville455]

4000 Will not be enough! It always costs more in the end! Buy this then have your heads done...


http://forums.maxperformanceinc.com/...59#post4462859

[bankbook]

Turbo!!

[Rugratman]

Carb professionaly built to your spec's.
Continental Convertor built to your spec's.

No kidding.

[Dustin68]

Originally Posted by grandville455

4000 Will not be enough! It always costs more in the end! Buy this then have your heads done...


http://forums.maxperformanceinc.com/...59#post4462859

X2!

[chiphead]

That 455 shortblock sounds like a good combo for a fair price.

The problem with dishing the pistons too much is that alum heads can tolerate more compression than iron for a given fuel. So if you dish for 9.5:1 with iron, you're stuck with that compression for alum heads with 72cc chambers. Flattops with aluminum heads can run 10-10.5:1 with properly chosen cam and machine work. And that makes more power everywhere.

It's been my experience that having a set of factory irons totally rebuilt and street ported will cost about $1500-2000. So compare that cost to a set of alum heads, and see what the budget shakes out.

Choose engine size, HP desired, compression ratio and pistons/heads. Piston choices change as engine size changes. Head selection changes based on compression, piston choices and HP desired...

Also consider the support systems for the engine. You WILL need to redesign the fuel system to support over 375 HP. Headers require moving the brake lines around. You will need a healthy radiator, shroud, fan, 11 bolt pump, etc. Good torque converters are $400-700.

[1funride]

I tell you, the chevy's I have owned in the past were much easier to get running. Cam, intake, exhaust...good to go. What about that approach, with a twist. Replace the rods and rod bolts with stronger stock spec units. Keep original pistons and a light hone and freshen up the rings. Use existing crank. Then use edelbrock d ports 72cc cnc ported. Replace cam with roller. Stay with 1.5 rockers. Or go over budget a bit and bore it and install some forged pistons as well, of course then you right there on the stroker kit.

D ports 2400 bucks
Rods and bolts 400 bucks
Rings
Roller cam 600 bucks
Still leaves 600 bucks for stuff in general.

Negatives would be the heads are no good for a stroker.
Not sure what it takes to install the roller, blocks changes?
Is it bad to keep stock pistons, are they a weak link? Is it possible.
What kind of power are people building with this combo?

I think it is crazy to have to spend 8000.00 to get a strong running Pontiac street engine.

[Engine-Ear]

First buy and read both Jim Hand's and Rocky Rotellas books.

If $4k was my limit, I would stick with iron heads, intake and probably LBHO manifolds. I would put $ into the rotating assembly (forged crank, rods and slugs), choose the right cam, converter (if going automatic), ignition and carb.

If it's a first-build, See if you can find an experienced builder who will help you put it together yourself.