Mr D.

(Also posted in Eng Mod Section)

As the topic says I'm looking for advice on which way to head in reguards to parts for my 1969 Project car. This is not a numbers matching thing so I'm wide open to your inputs. I'm looking to make around 400-450hp. Below is a list of parts I have to start from:
Engine
454, GenIV, 2-Bolt Block, Std bore
1969 Rect Port Heads, Closed Chamber, 110cc
1969 435hp Tri-Power Set up
427 Steel Crank, Std
3/4 of a set of Comp Cam Steel Roller Rockers. 1:72
Crane Cams Timing Chain and Gear Set
Complete set of tin and brackets for 69 427/435hp car

Drive Train
M-21
3:73 gears

I guess my biggest question is what Pistons and Cam parts should I use to complete this engine and get the best performance out of it. I have been looking at:

TRW L2300F30 pistons
Comp Cam 280HR

I'm so confused!!!!!

:D

verskel

Don't take this the wrong way, but the Tri-Power setup might be more trouble than it's worth unless you're going back stock with all the date codes correct, etc.

I'd save the tri-power or sell it for $$$ to use on more mods. Aluminum heads are nice, too if they're in your budget.

Ok guys, I started it......let's get some more input ! :cheers:

Mr D.

While I agree the Tri-Power might not be the best choice in todays market, I want to keep it for that Org look. Maybe at some point down the road I might get rid of it if it doesnt work out. But for now its 427 Tri-Power. :)

Simmo

Rect port heads need compression. Need at least 10.5/1. SRP-152148

Pocket port the heads.

Go for a solid cam 232 - 245 degrees on the intake with 112 degree lobe centre. Ask several cam grinders for a recommendation and pick the average.

Dont mix and match rockers.

Are you fitting headers, ideally you should. 1 7/8" 36" long primaries

blue427

I use a 280 comp in my 427 oval port,good till 6000rpm with rect port you might want to try the 292 comp. 2 bolt mains are good for 6000,make a 4 bolt out of it if in budget. :steering:

442olds

Bore out the block as large as you can afford. Then look at the compression heights of 454 pistons. Try and get a longer rod in that motor. The longer the better. You can reliablly crank up your compression if you put longer rods in and close up your quench height. There are more 454 pistons avaiable to choose from and you can get good rods pretty cheap for big blocks if you look in the right places. Speed-O-Motive has a good selection of I and H beam rods for sub Summit Prices.

As an example, I have +.4" longer rods in my 438 (427 bored .060 over with deck height of .007 above the deck crank stroke ground to 3.755", quench height .036"). I am running static compression of 11.75:1 (8.5:1 dynamic calculated) on 93 octane with intial timing set at 10 adv. It won't run under 6deg adv and 8 deg is not quite enough for a good cruiseing speed. I have ported iron oval port heads (260cc intake, and 116cc exhaust,113.5cc comb chamber). And a hyd roller comp cams XR282HR. It runs awsome and would really benifit from bigger rect port heads like yours.

I used JE Pistons but Speed pro and the others all have a wide selection of on the shelf pistons for 454's with different length con rods to choose from and if you play with the numbers enough you'll find a combo that will fit in the block. The long rods and larger bore combined with the short stroke help deter detonation. Also look into haveing the pistons ceramic coated on the tops to reflect as much heat back in the chamber. It also doesn't hurt to coat the head and valves.

If you have any questions or would like to discuss my combo further drop me an email. egrelle@et-motorsports.cc


[Modified by 442olds, 4:08 AM 3/9/2004]

Ironcross

Square port heads will give the best performance with a solid lifter cam and 11-1 pistons allowing a nice peak at near 7000 RPM :thumbs:

LT1driver

alum heads as budget allows and I would go with stock 435/450 (L71/LS6) solid cam :D

GDaina

:skep: You haven't run a tri power have you? Just exactly how is the tripower more trouble than it's worth? Set up? Only thing to set up is to choose jet sizes in the primary carb and power valves, same what u do on the 4 barrel.

I'm running a stroked 502 to 533 cubes, solid roller, and guess what the carburation....yup....the tri power from my 435. Couldn't have picked a better choise. I wouldn't switch to a 4 barrel if the intake or carb were given to me...bth, I have hi rise intakes and holley 4150/4160's to choose, so, it's not lack of intake or carb that made me go the tri power route.

The thing that's frustrating, is ludicrous comments that are made by uninformed people who don't know squat about the tri power setup

verskel

Okay, maybe Forum guys like you know more than me.......afterall it's just heresay, right ?!?!? :bb

All I know is that my immediate Corvette buddies (3 of them) have had or tried Tri-Power on their cars and either couldn't get it setup right or had trouble keeping it running..... :cuss ....so their advice to me was stay away from Tri-Power

But I admit that I don't know squat.....although my '68 runs fine with my poor mechanic hands. :p:

Ironcross

There is nothing wrong with factory tri powers. But once a pump jockey get their hands on the set up and trys to change the vacuum linkage to a progressive aftermarket style problems start. The front and rear do not have acceleration pumps in the carbs and the vacuum correctly provides the fuel on the engines demand. I should have bought a 67 435 unit several years ago to place on one of my big block Camaros. Together they provide a lot of CFM`s for a correctly set up engine and run terrific. Plus they look bitchen as hell. :D

Chuck Harmon

A lot of these same guys can't set up 4 barrel carbs worth a darn either. :(

Chuck

Tom454

GM TriPower is awesome and easy to set up if you know what you're doing.
People who have trouble with it haven't taken the time to understand the relatively simple principles behind it.

Personally, I like the "new technology" FI such as DFI/Accel ... computer interfaced and programmable. But there is nothing wrong with TriPower if you're competent enough to set it up right.

One thing I would definitely go for though is a set of aluminum heads. Less detonation & higher compression is possible which translates to more horsepower.

427Hotrod

I ran the same 427 in various cars over a 20+ year period. it went through many incarnations, oval port, rectangular port, open chamber, closed chamber, 9.8 compression, 12.2 compression, street roller cams, race roller cams, many flat tappet cams, single plane intakes, 4150 Holleys, Dominators, 1 -3/4" to 2" headers, LOTS of nitrous, 3.31, 3.73, 4.10, 4.56 and 4.88 gears, 4 speeds, 5 speeds, T-400, many converters etc etc.....

At 9.8 compression, home pocket ported oval ports, Holley Strip Dominator intake, 750 DP Holley, Crane .580/.600 solid flat tappet, T-400 and 4.10's would run 11.70's @118-119 mph all day at 3600 lbs in TX heat on street tires. It would drive anywhere reliably and made numerous 2000+ mile road trips.

Same basic set up with rectangular ports eventually ran 11.60's, but it took 4.56's and reving to 7500 rpm instead of 6400 rpm with the oval ports.

4 speeds were really no quicker..but LOTS more fun! Auto was boring!

Nitrous, compression and both rectangular and oval ports got it into the mid-high 10's at Denver's altitude. It used BIG solid roller at that time. Good for high 9's at seal level.

With oval ports and a little nitrous it ran 11.20's@133 on street tires in Houston. LOTS of fun on the big end!

I ran what seems like a gazzilion cams from many manufacturers over the years and I have a few favortites like everyone else. Whatever you run, I still would NEVER put a hyd anything in it. Solid only. You need around .600 lift at least with any head, stay with no more than 110 LSA angle. It will not be as smooth as 112, but it will run much stronger on the street. Duration in the 250-260*@.050 range on a solid flat tappet. Put about 4-6* more duration on the exhaust side for a capped up street motor.

By far, the best street combo overall, was the last one I had. It was the same basic shortblock with a 244/244* Comp street roller. 110 LSA and .623 lift. I used a very nicely ported set of Merlin iron oval ports. This sucker would pull like crazy and never laid down. It could pull down to 1000 rpm in high gear, and still rev to 7000 rpm as needed. It made 423 RWHP, capped up. Uncapped in typical engine dyno trim would be around 525-535 probably.

It ran 11.20's@123 in my Vette on pump gas with easy launches to keep from breaking parts. 3.36 gears and a 5 speed.

Don't worry about going up to a 454. A 427 will not dyno as well, but it will hang with it on the track just fine. If you're going to be stealthy, might as well go to a 496 with a 4.250 stroker crank and have real fun!


JIM

Ironcross

Fast car, with lots of different combinations. All with varoius solid lifter cams.
The ONLY way to FLY. Unfortunately, or better fortunally, many don`t know how to accomplish this. It takes more than buying parts, anyone can do that!. :lol: :thumbs:

Mr D.

Thanks everyone for the input. (427Hotrod, nice post) To give you a little background on this project, I started out with a 69 Coupe 427/435hp car in a box minus the engine. All I had from the start for an engine was a bare Tri-Power intake setting on my workbench and a whole lot of vision. I have scrounged around and came up with a 454 block 2-bolt, new GM steel crank, set of Dot rods out of a 502, set of LS6 heads. The chassis is now rolling (completely rebuilt) and bodywork starts next week. If is was mechanical it needed rebuilt, if it was rubber it needed replaced, and if it was painted it needed repainted. As you can tell there is a budget I'm working within to complete this project. That being said I have taken everyoneÂ’s input and some of my own along with lots of pricing research and come up with the following setup. Bare in mind IÂ’m not building a engine to take out to the drag strip.

BOTTOM END
Forged TRW-L2300F30 Pistons (about 10:1 or 10.25:1 compression)
Sealed Power Molly Rings
Clevite 77 performance bearings
Melling oil pump
ARP head bolts and main cap stud kit

TOP END
Comp Cams K Kit (Cam/lifters/springs/chain and gear)
Comp Cams Push Rods 7154-16, 3/8" .080 thickness
Comp Cams Roller tip rockers, 1411-16, 1:72 ratio

Comp Cam Choice #1

Magnum Hydraulic Flat Tappet 280H
Dur at .050 I-230 Ex-230
Lift I-.520 Ex-.520
LSA 110

Comp Cam Choice #2

Nostalgia Plus Solid Lift 11-671-4
Dur at .050 I-239 Ex-246
Lift I-.544 Ex-.539
LSA 112
Valves set at .012 vice normal .026

IÂ’m leaning towards the Nostalgia Plus as my cam of choice but still need to run the numbers on Dyno 2000 and get a comparison. My 66 vette had the 280H cam in it and ran and sounded great but there is something about a solid cam I like. By shopping around for parts and machine shop / Assy work I can bring all the used / new stuff into a complete long block for $3933.19, the price difference between the 2 cams is $86.00

What do you think?





[Modified by Mr D., 3:53 PM 3/10/2004]

72 Stingray

The LS-6 heads (iron, right?) with 10.0+ compression might not like pump gas too much. If you're not racing, is there any benefit in taking the chance?

Did you check the mass and $ of the TRW pistons vs. say... SRP?

Other than that, I would suggest to consider a Lunati 276/284F10 solid flat tappet. It's getting rave reviews elsewhere (dyno syms like it too):

http://www.chevelles.com/forum/ultim...c;f=4;t=019161

Do a search there. You'll find several satisfied customers. Its music is reported to be unique even among other solids. If I end up building a 454, I'll be using one.

Good Luck. :cheers:

Mr D.

Just plugged the number into Desktop Dyno. I'm using Canted/Rect Port, fully ported head profile for lack of anything better.

Hyd Cam
480hp @ 6000
482tq @ 4500

Solid Cam
517hp @ 6000
512tq @ 4500

427Hotrod

Are these original closed chamber LS6 heads or the ones off a later LS6 crate motor? If so the later ones are open chamber and will drastically change compression. May need to look at a different piston if so.

I know you're not racing, but you're leaving WAY too much power on the table with those cams.

And beware of DD fully ported stuff. To get any where near accurate numbers, you need to be real conservative on the head choices in there. Fully ported big block stuff would be in the near 400 cfm range. Stock heads aren't going to get close to that without MAJOR work!

JIM

GDaina

Get the Comp Cams 288 R solid roller, the one 427 described in his post, you won't regret it..cam pulls tons of vacuum, very streetable, idles at 800 and a tremendous power curve....starts to pull from 1000 all the way to 7000.