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Low compr., big valves - worth the work?

Low compr., big valves - worth the work?

Old June 25th, 2018, 04:19 PM
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Low compr., big valves - worth the work?

hi guys,

i bought a 73 455 engine with j heads. I put it in the car as it is, with new seals and the GM Hei.

I know the j heads are junk, so i bought large valve E heads. I donít want to pull the motor, because i have other work to do with the car but i want some extra hp.

Please give me any advise or tips, if my plan is good or wasted time and mony.

Setup:
- 455 Enigne, with low compression pistons 8,5:1 (from 73 toro should be 250hp version)
- E heads, filled crossovers and pocket ported
- thin head gasket for more compression ratio
- non egr performer intake
- i already have the 750 edelbrock performer carb
- headers, already installed, 3ď enxhausr system
- new cam with the right specs
- original valve train

Do you think it is worth the time?

thank you for any help

The engine runs fine and the compression is good but has only 250hp.

I have the OW W30 gearbox with W30 converter, this should be finde
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Old June 25th, 2018, 06:30 PM
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J heads are not junk, and here is a chassis dyno chart that shows this


http://www.dragtimes.com/images_dyno...preme-Dyno.jpg


http://www.dragtimes.com/Oldsmobile-...slip-9485.html
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Old June 25th, 2018, 10:10 PM
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While there is not complete info on what was done to the J heads, they might be just fine. And you'll notice it was done with a Quadrajet.


I am using a 455 with high compression pistons, stock J heads, a warmer than stock cam, Edelbrock Performer intake manifold, Quadrajet, cast iron stock exhaust manifolds in a 4500 Starfire with 3.42 gears and a TH400 transmission. I am sure it will be suitable to "fry the tires" if I would want to.
Run what you have and decide later what you want to do.
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Old June 25th, 2018, 10:36 PM
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Originally Posted by OLDSter Ralph View Post
While there is not complete info on what was done to the J heads, they might be just fine. And you'll notice it was done with a Quadrajet.


I am using a 455 with high compression pistons, stock J heads, a warmer than stock cam, Edelbrock Performer intake manifold, Quadrajet, cast iron stock exhaust manifolds in a 4500 Starfire with 3.42 gears and a TH400 transmission. I am sure it will be suitable to "fry the tires" if I would want to.
Run what you have and decide later what you want to do.

Here is more info on th DW's 84 Olds a few cars down. The J heads were home ported by him, and he runs just a few mostly mild aftermarket parts on it. Its a killer car, with high vacuum and low idle speed and good gas mileage. 12.6 with shorty headers and then he built some long tubes headers himself, to get down mighty close to 12 flats. To keep from boiling the tires off it he has MT tires and has hundreds of pounds of bags of fertilizer, in his trunk.He probably just forgot they were in there.


Things like Quadrajets or J heads are not what are holding people or their cars back. Yep, work with what ya got.





http://www.hotrod.com/articles/ccrp-...readers-rides/
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Old June 25th, 2018, 11:35 PM
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Originally Posted by Firewalker View Post
Here is more info on th DW's 84 Olds a few cars down. The J heads were home ported by him, and he runs just a few mostly mild aftermarket parts on it. Its a killer car, with high vacuum and low idle speed and good gas mileage. 12.6 with shorty headers and then he built some long tubes headers himself, to get down mighty close to 12 flats. To keep from boiling the tires off it he has MT tires and has hundreds of pounds of bags of fertilizer, in his trunk.He probably just forgot they were in there.
I always ran a full tank of gas and kept the spare tire in the trunk. Ballast was not permitted.

Things like Quadrajets or J heads are not what are holding people or their cars back. Yep, work with what ya got.
I agree.

http://www.hotrod.com/articles/ccrp-...readers-rides/
I couldn't get it to finish loading tonight, I would love to have read it.
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Old June 26th, 2018, 09:35 AM
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Mill the E head down to get compression up to at least 9:1 if you can , not sure how far they can go but they are already about 6 cc smaller than the J head chambers 77 to 83 or so. Seen some aluminum heads claiming milled to 64 cc that would be something I would run on a dish piston 8:1 455 to bring it up towards 10:1 and make the cam swap all the better. Milling the intake to match off course. Pushrod length change and adjustable rockers on studs too

Last edited by GEARMAN69; June 26th, 2018 at 11:18 AM.
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Old June 26th, 2018, 07:02 PM
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Many a spare in the trunk had something besides air in it, and also for bumpers, mufflers, and tailgates. One friend of mine made a 500 lb driveshaft loop out of old drill casing, for his altered he welded into the frame right in front of the rear end. Since it was in plain sight, it certainly wasn't hidden ballast. The fastest may have appeared to be like most others much of the time, but seldom were. Creativity, innovation, and deception were the name of the game and still is. Of course you have to understand chemistry, physics, and have other skill sets. This led to an ability to tune cars and chassis and an understanding of the trial and error process.


Just a spare huh


The J heads are fine, but could be ported and have better valves and valve jobs used, and then you could use a smaller cam then you probably have. But for a street car none of that probably matters. Increasing timing and or compression is probably good, as well as better gear ratios. And if the suspension sucks for take off you would probably just be spinning your tires more.





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Old June 26th, 2018, 11:03 PM
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I am by no means an expert but

If you haven't already spent the money to rebuild the E heads you might try Edelbrock heads. They have a smaller compression chamber. At least the 455 ones do. I asked my builder why he bought dished pistons and he said the Edelbrock heads with those Pistons would give me 10:1 compression. do your research to see. Good luck with your project.
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Old June 27th, 2018, 05:32 AM
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Bernard sells the aluminum heads for far less, and can mill them down to whatever and port the intakes and install the larger valves which are usually recommended for even more air flow. Weight savings is about 40 pounds for the pair over iron and no exhaust crossover to fill like sometimes done on the factory heads.



https://www.ebay.com/itm/BERNARD-MON...UAAOSw9fRZ1TbV


To me, the iron heads work fine for most street Olds, if you already have them and they are already in good condition. Its when they are in need of rebuilds and you want to modify the iron ones the aluminum ones start to make sense dollar wise.
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Old June 27th, 2018, 07:32 AM
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Guy,


Re read his first post.. he already bought some E heads
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Old June 27th, 2018, 07:44 AM
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Originally Posted by GEARMAN69 View Post
Guy,


Re read his first post.. he already bought some E heads

That would not be Edelbrocks, but OEM E heads he says he has with filled crossovers.


http://nichibei.tripod.com/headflow.htm
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Old June 27th, 2018, 07:45 AM
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Thank you for the answers. I think the most forget that i have some big valve e heads, and the j heads are already running in the car.

I find out that the 71 W30 have also 8,5:1 cr with big valve heads and it makes around 340hp.

With the other modifications i expect around 350-380hp.

I am already in contact with comp cams to find the right cam.
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Old June 27th, 2018, 07:59 AM
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The net horsepower was only 300 for that engine, though the gross was listed as 350.



https://musclecars.howstuffworks.com...4-4-2-w-30.htm
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Old June 27th, 2018, 08:42 AM
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I find out that my 73 Toro engine has a net rating of 250hp as it is.

With the heads it would be 300hp. The additional stuff and work would produce about 50 hp i think.

This would be a power increase about 100hp from 250hp to 350hp net. I think this would be worth the work.

Please correct me if i am wrong
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Old June 27th, 2018, 11:10 AM
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Originally Posted by Firewalker View Post
Many a spare in the trunk had something besides air in it, and also for bumpers, mufflers, and tailgates. One friend of mine made a 500 lb driveshaft loop out of old drill casing, for his altered he welded into the frame right in front of the rear end. Since it was in plain sight, it certainly wasn't hidden ballast. The fastest may have appeared to be like most others much of the time, but seldom were. Creativity, innovation, and deception were the name of the game and still is. Of course you have to understand chemistry, physics, and have other skill sets. This led to an ability to tune cars and chassis and an understanding of the trial and error process.
There were some "tricks" used. Everything from bronze bushings in the control arms to cement filled spare tires.

Just a spare huh
Yup, just a "real" spare tire.

The J heads are fine, but could be ported and have better valves and valve jobs used, and then you could use a smaller cam then you probably have. But for a street car none of that probably matters. Increasing timing and or compression is probably good, as well as better gear ratios. And if the suspension sucks for take off you would probably just be spinning your tires more..
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Old June 27th, 2018, 11:21 AM
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Originally Posted by Bastler View Post
I find out that my 73 Toro engine has a net rating of 250hp as it is.

With the heads it would be 300hp. The additional stuff and work would produce about 50 hp i think.

This would be a power increase about 100hp from 250hp to 350hp net. I think this would be worth the work.

Please correct me if i am wrong

You're wrong, and by the way the 76 numbers were only 215 net hp


But are the numbers to be trusted at all net or gross, for any given year or model. Its all about sales and corporate policy and more. The first or earlier years numbers came off an engine dyno. The net numbers came off actually as it would be installed in a car and possibly rear wheel power numbers.


But besides this the power can be lower because of changes to the cam, compression, timing, manifold, or carburetor settings for emissions and mileage goals. I would be surprised, if the best OEM head was 10hp better on a stock engine below 4-5,000 than the worst heads. They all flowed about the same really.



The 455s were designed for low rpm land yachts where torque and mileage matters and thats where it really can excel cheaply, with more compression, small cams, quicker timing, and ported heads and better intakes and exhaust manifolds.


I would advise paying no attention to a peak hp number, but the avg torque numbers for the street and it probably would pay off well at the track. Of course those who want to see you things try to get you focused on the high HP numbers, or they know you want the wrong things and will sell you that way. The sales matter to them and not how well it does normally. Want a loopy idle?? They will give you all you want on sound, just like you are a top fueler or a Pro Stock car. Its just more overlap and unburned fuel, and generally in an Olds will run slower and be a pain.


Some nice ported and milled heads would be a good start on most stock engines seeking more power, but then you have to get the intake and exhaust manifolds modified or changed out, to get all of it. A little more horsepower, but a lot more torque.
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Old June 27th, 2018, 11:39 AM
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It depends on the year, and under what rules the racing was done what happened, or could be done. I liked AHRA LOL Then IHRA.
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Old June 27th, 2018, 12:07 PM
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Bastler........ Don't get caught up in these HP numbers unless you are building a "race motor". Your engine won't be operating in that range 99.99% of the time. Idle to about 3,500 rpm's is where you should focus. You're never going to know what horsepower you have unless you run it on a dyno.


Firewalker...... I was running NHRA stock. Now it seems that everything is "E.T. Brackets". Now, I would just build something and run it.
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Old June 27th, 2018, 12:16 PM
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Originally Posted by Firewalker View Post
That would not be Edelbrocks, but OEM E heads he says he has with filled crossovers.


http://nichibei.tripod.com/headflow.htm

LOL , I wasn't even thinking that it could have been casting E .. LMAO
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Old June 27th, 2018, 01:42 PM
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Originally Posted by OLDSter Ralph View Post
Bastler........ Don't get caught up in these HP numbers unless you are building a "race motor". Your engine won't be operating in that range 99.99% of the time. Idle to about 3,500 rpm's is where you should focus. You're never going to know what horsepower you have unless you run it on a dyno.


Firewalker...... I was running NHRA stock. Now it seems that everything is "E.T. Brackets". Now, I would just build something and run it.

Amen on the horsepower and the power range, though I would extend it to 4-4,500 on the top of the range.

I figured you got stuck with NHRA, though there is some good and bad to it. Now a days the local bracket racing track is NHRA. What a joke. But I did hear there is a more informal racing going on there now, after hours. When I started going out there in high school it was a major National track for AHRA and all the big guns came for many reasons.

For one thing it was all straight and level and concrete, and was the longest of them all, so stopping was not an issue. Perfect for new cars or drivers with tons of power on hard small slicks, or if you wanted to make a record attempt past what the brakes might normally handle. The "Tree" then was a used traffic light hung between two poles with it in the center. No ETs, but mph clocks and we spotted by car lengths drawn on the concrete. The winner was determined by the flag men on each end, and on the far end you stood between the two lanes. It was all volunteer work. As a teen, I liked being on the far end in the middle of the track with cars flying past me. Sometimes in control and sometimes not.


The pits and spectator sides were also all big wide concrete. It was a new and briefly used WWII bomber training base given to the city right after the war ended. Then I was born, and set a new national record in my class with a stock 63 Cutlass automatic 17 years later the summer before my senior year at the Nationals held here. Lost Little Stock to the reigning champion out of Arizona. It was a turbocharged corvair way faster than me, and I had to spot him. I have raced many things before and since then. and learned.



I just go the store now and grin. That's the real thrill is being able to just drive on the streets without the headaches or expenses and work. I don't care what people think, but do try and help them out to see the light and learn the craft in all things. I never ever pick on people and never really did.



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Old June 27th, 2018, 01:46 PM
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Originally Posted by GEARMAN69 View Post
LOL , I wasn't even thinking that it could have been casting E .. LMAO



Its OK I have a slip up every few years, as well, though they seem to be coming more often now.
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Old June 27th, 2018, 09:06 PM
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Those pistons literally have 40cc dishes. I personally would not put any money into an engine with those pistons. With a Fel Pro Blue gasket you could in fact be below 8:1.
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Old June 27th, 2018, 10:44 PM
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Only for comparison, my 72 455 cutlass convertible I think came with 250 hp but with a better cam ( mild) ported and blended G heads with small valves and flat top Pistons w/ clearances for the valves and a repop w-30 intake and quadrajet engine dyno'ed at 326 hp and 450 ft lbs torque. To the wheels loses about 20% I'm told. Never put the car on a dyno to get " to wheel HP". My earlier post about the Edelbrock heads was referring to my latest build where my E heads I had him check before just taking the word of the seller they were good verified they needed rebuild at a cost of 1500.00. I opted for the Edelbrock's, at 600.00 more they already flow better and I dont have to pay extra to port polish them like I would have to with the E head, personal choice I guess. As for the cc of your current Pistons your builder should advise you if he is good on the path you take from here. Good luck with your build.
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Old June 28th, 2018, 08:13 AM
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Bastler.... Now, what are you thinking ? Lots of info to digest.


Firewalker..... 3,500 is the high end rpm's for torque. Horsepower with a mild cam, power will peak out by 5,000. "Tire churning" in town is limited by traffic and speed limits.


Our track was NHRA for many years, switched to AHRA then to IHRA and now back to NHRA. The sanctioning changes were due to insurance costs for the drag strip.
The pits were dirt, blacktop for the track. Several years ago, some concrete poured from the starting line to about 200 feet.
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Old June 28th, 2018, 01:12 PM
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Originally Posted by OLDSter Ralph View Post
Bastler.... Now, what are you thinking ? Lots of info to digest.


Firewalker..... 3,500 is the high end rpm's for torque. Horsepower with a mild cam, power will peak out by 5,000. "Tire churning" in town is limited by traffic and speed limits.


Our track was NHRA for many years, switched to AHRA then to IHRA and now back to NHRA. The sanctioning changes were due to insurance costs for the drag strip.
The pits were dirt, blacktop for the track. Several years ago, some concrete poured from the starting line to about 200 feet.

Here are some pictures of our massive all concrete track, when being built and in operation as a B-17 bomber training base. With almost 9000 feet of dragstrip runway stopping was not a problem.



http://www.airfields-freeman.com/NM/Airfields_NM_SE.htm




The problems came for the dragstrip here by the late 60s, when a con man came to town, with the scam of the "Crossroads Intercontinental Airport". The City bought the scam scheme and canceled the lease on the base with the Charioteers, which made the city lots of money from all the racers from all over coming here month after month and getting bigger year after year. AHRA lost a major dragstrip in its chain.




The scam was realized by the City, when the scammer left town one night with a lot of their money. But dreams of massive wealth die hard and they continued trying to make this area something it was not, so they refused to lease it back for racing again, and instead gave it to an International Soaring club for use. Once a year for a one week meet...By the mid 70s the actual racers had moved on and a younger group of wannabe racers went to the city, to get it open as bracket racing and they agreed. I believe it was IHRA sanctioned then in the mid 70s, as the AHRA had taken a big hit by the early 70s.


More history on the AHRA


https://en.wikipedia.org/wiki/American_Hot_Rod_Association


http://www.hotrod.com/articles/the-s...-ahra-insider/




Today brackets and the return of actual racing as the gunslingers return, with heads up racing more like pinks. With the Clocks turned off, or so I have heard.


https://www.google.com/search?safe=o....0.gq_FujF_X9U




Its getting hot and heavy here again, as the money from oil has been pouring in for the last 15 years into their collective pockets.


I just want to have fun going here and there, with my light weight mild 461 beasty. As they notice I am working on it updating it, in my driveway, I am beginning to here some heavy weights cruising by here racking their pipes.


The updating mechanically was to a set of ported aluminum heads, with .050 shaved off. The new intake is a crosswind. The cam is now down to a Crane .222 .230 at 110, from the 234 113 I had in it for 15 years. I changed the transmission from a 3000 B&M stall Turbo 400, to a 2000+ stall 200r4. Switched rear gears from a 2.80 gear down to a 3.55. With the change of water pump, manifold, and heads it chopped off 110 pounds over the front wheels. Cranking compression is now 210 where it was 180. Thats from the head shave and cutting the overlap in half. I went from steel chrome wheels to the last race wheels Greg Weld made.


http://i30.tinypic.com/2m6lx06.jpg


Run a stock points distributer, with a unilite module inside hooked to an analog MSD6. The wires are 8mm BlueMax spiral cores. Switched from my trusty powerful Promaster 29440 coil, to a Ford TFI one. 10 bucks from Standard.FD478 TruTech


Holley a 900cfm TBI on it since those came out, but I want it gone, and have a 750 Street Demon to replace it. Torque torque torque.


But I am really just wanting it for my trips to stores, so the common driving never gets old and boring. A daily driver. A practical daily driver. I even have LED headlights installed now.
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Old June 28th, 2018, 02:57 PM
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With all the up grades how fast is it in the 1/4 mile? Back to the OP even gear change and a better intake would help! Your pistons is your bottle neck!
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Old July 1st, 2018, 02:37 PM
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Originally Posted by OLDSter Ralph View Post
Bastler.... Now, what are you thinking ? Lots of info to digest.


Firewalker..... 3,500 is the high end rpm's for torque. Horsepower with a mild cam, power will peak out by 5,000. "Tire churning" in town is limited by traffic and speed limits.


Our track was NHRA for many years, switched to AHRA then to IHRA and now back to NHRA. The sanctioning changes were due to insurance costs for the drag strip.
The pits were dirt, blacktop for the track. Several years ago, some concrete poured from the starting line to about 200 feet.
i think i will wait and build a high compr. Engine maybe with the edelbrock heads.

thank you all for the help
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