Guys,

I have a Ultra clean 69 with a 350/350 Engine, Engine has orginal Bottom end 11.1 Pistons and the original Double hump head. Engine has LT1 Cam solid lift. Roller Rockers, Torker II intake and A Holley 650 DP carb. New HEI dist. with an MSD Ingntion.

The trans is the orginal munice 4-speed with a hurst shifter added. and the rear end has 4.11 gears.

Car is quick but I have the bug for MORE POWER... and I'm looking for some suggestions, the best place to put money in the engine and get the most performance. Would a set of aluminum heads help make some noticeable power?

I imagine the engine is somewhere in the neighborhood of 400HP if the stock engine was suppose to make 350...

I want to get around 500 to 550HP.

I run a 50/50 mix of 93 Octane and 104 Octane. This is a toy and I don't mind running a premium fuel.

I plan to go through the suspension and do some udating and upgrading for better handling put want to keep the 4.11s and the 4-speed.

I looking for suggestions to get me in the 500 to 550HP range I mentioned so I can eat these new mustangs and Challengers up...

here is my ride for your assesments:

http://holtautosales.com/slone/


http://www.youtube.com/watch?v=9kEOY...e=channel_page

 

Your desired horspower range would necessitate a total rebuild or new engine.... attention must be given to the whole combo, not just a set of heads or some bolt-on parts. These links may give you some ideas of what you need and how much you would have to spend:

http://www.amerspeed.com/cgi-bin/showenginetypes.cgi

http://www.airflowresearch.com/chevy_dyno.php

BTW, Great looking car!!!

 

IMHO, that's a really nice combo. I had something similar with my L-46 with an LT-1 intake and carb, and really liked the engine.

I'd note in passing that you'd likely see better driveability and more torque in your existing engine with a GOOD dual-plane vs. the Torker II single-plane.

I agree that the shortest, cheapest route to that power figure would be starting from scratch. 500 HP from 350 CID in a GEN I requires some real effort and investment. And of course if that's a numbers-matching engine you may want to set it aside. 11:1 isn't really a streetable CR even with aluminum heads - it'll run, but I suspect you're giving up power with the limited ignition advance even with the gas mix you're using. Finally, that's an old shortblock any way you cut it - I give you an 80% chance of busting the bottom end at these power levels within a relatively short time

If you're dead-set on keeping your existing shortblock, your options are kinda limited to hit that power - basically mondo heads (210cc+ runners) and a retrofit roller cam to match (.600+ lift along with that Torker II (or a better single-plane) and a 750 CFM carb. You're going to have to turn it 6000+ RPM to make 500+...and you're going to break it

Starting from scratch opens a ton of options for a streetable 500HP...but I suspect that's another thread as it's not what you're asking in your post.

This is a real generic answer, but it gives some idea of where you'd need to head.

Good luck!

 

If the engine's original to the car pull it before it breaks. 500 plus HP is as close as a Jeg's, Summit or similar catalog, or your local Chevy dealer's parts department. Pump gas capable, and no wondering if your chosen build will make the power. Not exactly cheap, but how fast you want to go usually comes down to how fast you want to spend.

 

AFR 195 heads (street or comp port) and a hyd or solid roller around the 242@.050 range will give you 500+ easy.

 

The engine has about 5k since the rebuild. It is the 350/350 Shortblock with the 4 bolt mains. Will it hold up if I switch the Heads and Cam. and put a 750 DP on top? I have the rev limitor set at 6000 RPM. I would proubably keep it that way. Some had said the Older style bottom end will not hold up?

Also whats the performance difference from the Heads I have to he suggested AFR 195's Will it be huge? ot just barely noticeable..?

 

These are two very different statements - so the engine has been overhauled? My comment was targeted at your first statement that the engine was original (i.e., 40 years old). A correctly assembled 4-bolt main GEN I with all forged components will hold 500 HP, although it is at the absolute limit of what I would build with the stock block. Can you confirm that this is all forged and internally balanced?

 

That is a very nice looking 69, The pic outside hooters is the best of course

with those pistons You could get 450Hp and even more TQ, maybe 460-480TQ , fairly easily and still not a Radical power mod. Your car is way too purty to go wild and loose driveability.
You would want a 5 or 6speed /with an OD gear to take advantage of the considerable power upgrade. Richmond ROD, or a Tremic. either will fit a 5speed OD will be easier to install.

My 2 cents worth is, AFR 195's or Brodix IK200 heads,Felpro 1094 head gasket , retro fit roller assembly Kit. to get 6-6.5K rpms , Comp Pro magnum rockers, New Comp timing Kit. New ignition, MSD pro Billet/w 7.5mm wires and 6al box, Edelbrock RPM airgap manifold , Demon 750 manual secondaries carb.

Use a "max" dropbase canister to fit under your 69 hood or better yet get a L-88 hood paint it and install to get your aircleaner up there where it should be.
Your car may handle the new power just fine or you may look at new & better Rear suspension Parts and shocks.

With the above or similar You would have the purtiest 69 around and Kick those new Power Mustangs azz into the bargain...Good luck have fun,
Vettester ,A fellow High powered 69 street owner.

 

5.7 liter version of the ZO6 LS3 makes 405 hp has very high compression good breathing heads with light sodium filled valves the roller cam pulls past the 6000 rpm mark to get that 405 hp.

Do you really believe your 5.7 liter very poor air flowing heads solid
flat tappit cam being run less then 6000 rpm ( rev limiter ) is putting out a true 400 hp. Its not very close, how do expect to take the same 350 size engine restrict it to shifting below 6000 rpm rev limit come up with 500 to 550 hp.

 

No comparison on the heads, youll feel it alright. Do the roller upgrade and set the rev limiter to 6500 or so. Ive seen bottom ends like yours hold up to 6500 rom blasts all day and others pop after an afternoons fun.
Did you get upgraded rod bolts on the rebuild?

If it were me (put the original motor aside) spend a little more on an upgraded bottom end, go solid roller and twist the living pee out of it. Im telling you youll love it.

Or for roughly the same money you can stroke it and bring the powerband so it peaks a little sooner and get a nice boost on torque


Page tpi421Vette in the C4 section he can get you a swinging deal on a set.

 

I'd estimate the current engine is making around 330-340HP.

 

Very nice car,seems like it would be a good performer the way it is. Any track time on it?

 

I'm no Horsepower expert for sure! I have done some engine installs and mods but do not claim to know what combos are best suited for eachother... I was going strictly on the Engine from GM was rated at 350HP? and has had some mild upgrades. and the speed shop that put the new headers and exhaust said they figured it to be in the 400 range??? Guess...

The speed shop also told me that my engine would love one of the new 4150 - 750 Holley DP. I have the old school classic 650 DP currently.

I have not had it to the track. And the reason I was saying I wanted to stay at or around 6000 RPM was to avoid breaking. It has seen 7000 RPM a few times but not planing to make a habit of it...

Honestly the Engine work was done before I bought the car so I'm going on what I was told. They did not specify if the bottom assmbly was balanced or blueprinted. Just that it was rebuilt. the heads were definately completely overhauled it has all new screw in studs, guidplates and springs, pushrods... When I adjust the lifters you can tell the heads were done right... Or at least appears to have been. The car carries good oil pressure and does not smoke at all. IT runs real good...but just like a crack addict...I want more...

If throwing a set of heads on the car and a new 750 DP will be a lot quicker maybe I just do that? Throw $2500 at the current engine and see what happens...If the bottom end does'nt hold up I could buy a great short block and put ti back together....

Jegs has a Holley Top End Kit that claims it will make 440HP

http://www.jegs.com/p/Holley/Holley-...46541/10002/-1

Thanks for all the options! this is a great help! Many thanks!

 

The holley top end kit comes with stuff your not going to be able to use the high rise dual plane manifold won't fit under your hood, it has a vacuum carb a hydraulic cam. I would suggest with you having 4.11s, 4 speed trans you go to a 750 dp mechanical secondaries and keep using a more modern version solid cam combined with a really good set of modern heads, but to get any real power out of your 350 like you want your going to have to plan on higher revs then any 6000 rpm. Assuming your short block was put together right the steel crank, forged pistons will take alot, factory rods would be the only weak link if you could even get it to 500 hp, but for short periods of time with more hp more then 6000 rpm it should handle it. Its not like your going to take the engine up to say close to 7000 rpm keep it there for long periods of time like an oval track car would do, anybodys street car is going to see high rpms from anywhere to a few seconds to maybe just a few minutes out on the freeway at speed. Think about it if your car at the drag strip runs say a low 12 second quarter mile how long out of this 12 seconds would it be at 7000 rpm, you drop the hammer at say 4500 it climbs to 7000 you shift it drops back off of 7000 rpm some. I can never understand why people panic if they see a little rpm for a short time, you would think they were trying to run there engine at 7000 rpm 100 percent of the time for a 500 mile race.

 

tread lightly. matching numbers. Suggest pull & stow OE motor; then build another block to suit you.

 

Given this, I would suggest - strongly - that you just have a competent shop do a quick look to see what you have. It doesn't have to be torn down, but getting down to the shortblock would likely clarify what's in the engine and what your options are.

I've torn down a bunch of "really hot" engines that turned out to be collections of garbage sitting around in someone's shop.

Sounds like you've got the money to do this right - so find a good shop and tell them what you want.

 

N2o................

 

Got carried away (I love a well built 450HP sb) and Forgot to mention, in the long haul you may get caught up in a rebuild and Lose the value of a car like yours. My 69's original engine was long gone, that set me free to build it up. Cars like yours I agree with Jackson.

 

When you move into that HP/TRQ range with a 40 year old vehicle, you'd be wise to inspect/replace upgrade the drivetrain with HD parts and possibly larger half shafts. With that much TRQ and your current diff ratio, you will be smoking the OE sized tires, so you should consider larger wheels and tires to get the power down.
You should also rebuild the brakes or upgrade to wilwoods or similar.

Be prepared to spend 2 to 3 times what you think it will take to get everything right and safe.

 

One last comment , from me.

If your serious about Not getting embarrassed by New mustangs Or any new OEM Performance car including the asian Ricer's, youll be dissapointed regardless of what HP and TQ you make. Its all about the Gears when dealing with any new performance cars. You jump on it and pull out then 5-6 seconds later some little Japanese car is pulling away while your in 4th Gear trying not to blow your engine, and they KNOW IT .Your Muncie wont let you embarrass any other cars exept off the line for 10 seconds. But when You shift into your .62 overdrive gear that starts making power at 3500rpms and 95mph, theyll back off embarrassed as hell as you walk away at 100, 110, 120, 130, and still pulling while under 6000rpms. Thats true glory for a C3 corvette owner.
They know you dont have the old Muncie anymore!!