Sporty-X 03-20-2008, 06:35 AM hello,
i plan building a 454 block for my second car, and use it as an occasional driver and use it at the track sometimes.
I juts want to have a nice enjoyable car. My first car stays my 96 camaro.
So my question is :
I already have :
454 block
cast crank and standard rods
Keith Black pistons KB207 with -25.5 dome
stock heads (large oval)
i plan to be in the 500 to 600 hp mark with an engine not reving higher than 6000 RPM.
First question is : is this possible with what i already have or is there already limitations from them ?
If not, i planned to get and Edelbrock Performer RPM Air gap manifold, and wonder which cam would be the best for such a setup ?
Every suggestion would be appreciate.
Thanks
rskrause 03-20-2008, 08:36 AM hello,
i plan building a 454 block for my second car, and use it as an occasional driver and use it at the track sometimes.
I juts want to have a nice enjoyable car. My first car stays my 96 camaro.
So my question is :
I already have :
454 block
cast crank and standard rods
Keith Black pistons KB207 with -25.5 dome
stock heads (large oval)
i plan to be in the 500 to 600 hp mark with an engine not reving higher than 6000 RPM.
First question is : is this possible with what i already have or is there already limitations from them ?
If not, i planned to get and Edelbrock Performer RPM Air gap manifold, and wonder which cam would be the best for such a setup ?
Every suggestion would be appreciate.
Thanks
Where you need to concentrate is the heads. You are going to need high quality porting to approach your hp goals. Which specific heads do you have? Runner size differs quite a bit on the different castings and this may be the ultimate limit on how much airflow you can get out of them and thus be the limiting factor in hp. The better the head you start with, the less time consuming and costly the porting needed to achieve the desired flow. With your hp goals, do not use a dual plane manifold. A small runner single plane is much more compatible with a 6,500rpm mostly track engine.
Rich
angel71rs 03-20-2008, 10:43 AM KB hypereutectic pistons have a rep for breaking at the top ring lands. The high silicon percentage and the heat treat makes them very wear resistant and stiff, but they will break instead of bend. KB will blame it on insufficient ring gaps (they call for wider than normal gaps). On a computer controlled engine, not as big an issue; the computer will pull back timing if knock is detected. With traditional distributor/carb... don't make any mistakes on the tune.
I've seen guys make 500 engine hp with big oval heads reworked with larger valves/mild port, flat solid cam ~ 240*, 750-850 Holley, and either the Perform RPM Air Gap or small single plane. I'd go with the RPM intake if you want it to feel strong on the street, single plane if peak hp at the track is more important.
You might want to price what it will cost you to rework the stock heads vs the price of aftermarket heads. Keep in mind some aftermarket heads require extras like specific head bolts. Roller cam will make more hp, but for a lot more $$$. Not needed to make the lower end of your target hp.
Rice Killer87 03-20-2008, 04:45 PM I had a 79 Z with a .060 454 10.0:1,781 oval port heads,single plane intake w/ a flowed 850 Holley and a 244/244 .550/.550 Comp Cam (Magnum 292 cam actually....came w/ the motor). It went 11.0's in the 1/4 which make it right around 500 HP and was very streetable w/ only a 3,000 stall and 4.10 gears. And it was only a hydraulic camshaft so I only went through the valves 2 or 3 times the whole time.
So thats about what you need/asking for as I shifted it at 6,000.
Im actually still using the bottom end in the 86 race car....except it has 990 casting rect. port heads and a .714 lift solid roller in it...different intake and 1050 dominator. It WILL be faster this season that whats in my sig. It had 5.43 gears in it and we just put 4.56's in.
Sporty-X 03-20-2008, 06:38 PM which single plane manifold you suggest ?
Stephen 87 IROC 03-20-2008, 07:45 PM Victor
Sporty-X 03-20-2008, 07:52 PM oky , i will look at noon at which casting i have, so i can let you know.
I have also a friend building another engine with flat top Fel-Pro hypereutectic piston.
He has small oval heads. He plan to change them for aftermaket ones, but not now and he wonders the limited HP he can get from these heads. Any idea about it ?
Sporty-X 03-20-2008, 09:42 PM i looked at my heads : casting number is 353049.
i made a search about opinions on them and it seems good heads.
rskrause 03-20-2008, 09:50 PM Victor Jr. 454-O #2904 850CFM carb.
Rich
Stephen 87 IROC 03-21-2008, 11:44 AM The 049 and 781 castings are some of the more common and better oval port heads. Get some 2.19/1.88 valves installed and do some port and polishing to help them breath a bit better.
For your HP goals, find a cam in the .600-.650 lift range that's considered a street cam since you're not building a track only car.
rskrause 03-22-2008, 08:22 AM BTW: I prefer vacuum secondary carbs for the street. You need a cam with a fairly narrow LSA (108-110) and duration in the 240-245 degree @ 50 range.
Rich
byrons1502 03-31-2008, 09:11 PM have a 454 with kb 207 pistons,.039 head gasket,large oval ports. 049 heads, 2.19/1.88 valves. heads were ported on the exhaust side,bowl hogged. victor jr, custom solid cam with 224-229 at 050 with a tad over 560 lift. edebrock 600 carb,stock fuel pump ls7. stock hei. hooker headers. made 383 rwhp in full size truck on 87 octane.
with the 207 pistons and stock heads,.039 gasket,block not decked the compression will be around 9.5 to 1. not the 10.1 to 1. you need to zero deck the block and mill a little off the heads to reach the 10 to 1 spot. i just dropped it off tonight for a refresh and planning to install a comp 292 with a 950e85 carb and shooting for 570-600 hp.
the cost to do heads is going to run about the same as a decent merlin head. run the merlins,comp 280-290ish extreme performer rpm air gap, 850 carb, put wavre loc rod bolts in. keep it under 6300 rpm and have fun. you should be in the 550-600 hp range
Sporty-X 04-07-2008, 06:56 PM thanks for the last post. I didn't remembered the zero deck would help so much on compression ratio.
I already bought wave loc bolts.
I plan to start with my heads and not spend so much money on them, so i can change someday and see what i can have with them.
What about valvetrain ?
Chrome383Z 04-08-2008, 02:27 PM I've never jumped into the old school big block world; but for those horsepower numbers and the rpms you will be turning I wouldn't neglect the bottom end. I don't know what they can handle factory, but for a reliable engine i'd at least upgrade to a forged crank and ARP rod bolts. Forged rods if you can swing it.
rskrause 04-09-2008, 06:31 PM I've never jumped into the old school big block world; but for those horsepower numbers and the rpms you will be turning I wouldn't neglect the bottom end. I don't know what they can handle factory, but for a reliable engine i'd at least upgrade to a forged crank and ARP rod bolts. Forged rods if you can swing it.
The stock Gen IV stuff is stout. There is many a 500hp bracket car making pass after pass with 2-bolt block and stock crank and rods. Nearly all the cranks were forged, most of the blocks are 4-bolt, all the rods are forged (though there a couple of different designs). The best of the stock parts are certainly good enough for 700hp, maybe more. The motor in my bracket car uses a stock crank (one of the good ones) and is reliably over 700rwhp.
Rich
byrons1502 04-20-2008, 12:24 AM get good valvespring and some lightweight retainers with 10 degree locks. i like the comp beehives. i use the magnum pushrods because they are cheap and lightweight. i also like the comp magnum rockers but that might be a little overkill. the stock rockers should be ok for a budget. try to get light bbcs are heavy on the valvetrain
Sporty-X 06-03-2008, 01:01 AM hello again.
My engine is in rebuild now. I discovered that one exhaust valve had a crack on it and i lost one other while rebuilding the engine so thinking in putting 2.19 and 1.88 ones.
What about Summit stainless steel "race valves" ? they are cheap so i would like take them.
Also, i'm wondering if the KB pistons will make need of balancing the engine and if yes how to have it done ?
Sporty-X 06-03-2008, 01:30 AM also others questions :
1) valve train : i have taken a complete set from COMP with a 292 cam, springs , lifters, etc but there were no pushrods in. Can i stay with my stock ones ?
2) main bolts : i've seen a post telling main bolts could be a bad issue especially if old engine. Do i have to change them ?
Rice Killer87 06-03-2008, 03:24 PM What kinda power is the motor gonna make,roughly? If its under 550,I would say the Summit valves are ok but use the factory size.
Changing pistons means changing the weight of the rotating assembly. YES it needs to be rebalnced and a machine shop has to do that on a special balancing machine.
NO you cannot use the stock pushrods. You need hardened chromoly ones...and with those you will need larger pushrod guide plates...dont worry,their cheap.
Main bolts are cheap insurance...prob. dont need to replace them but if you have the extra money to burn,buy some ARP ones.
Sporty-X 06-03-2008, 07:21 PM I expect being at this level of power and maybe more so I will take some others valves. what is the problem with having bigger valves ?
About pushrods : what should i take ? i've seen them in 3/8 and 7/16 ? What lenght too ?
Main bolts : i found ARP at summit but it written nowhere if the scraper can be putted in place again with them ? Does this scrapper really important ?
Stephen 87 IROC 06-03-2008, 08:02 PM In a old engine, it's wise to replace all the bolts including the head bolts.
Even in my engine, I only use 3/8" pushrods but with the .080" wall thickness. As for length, you can gamble with stock length but chances are you'll need to use a length checker and order them in a specific length. Too many factors will determine the proper length.
I don't use a scraper or windage tray in my engine but I do use a deep sump pan and only fill enough oil to fill the sump up to the baffle.
There's usually no issue with using bigger valves after the seats have been cut to use them. A 4-1/4" bore block shouldn't have any wall clearance problems with bigger valves and it depends on the exact piston and cam grind to determine if there will be any piston to valve clearance problems.
Rice Killer87 06-04-2008, 03:47 PM As long as your running stock style hyd. lifters and the heads havent been milled you can prob. get away with using stock length pushrods.
Nothing wrong w/ bigger than stock valves,I think its just a waste of money unless the motor is going to put out 600+ HP. Get a good valve job done and roll on with it.
Sporty-X 06-09-2008, 07:24 AM oky
thanks for these advises .
what is the stock pushrods lenght ?
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