Re: Longer push rods ?
 

I have come to the conclusion that the typical OEM mass produced, union labor assembled typical car engine is the most forgiving invention made by mankind. Almost all of them run quite well, some in the face of incredible abuse, others with almost nonexistant maintenance , and practically none of them are anywhere near right. In considering all of this, they truly are an amazing device!!

Re: Longer push rods ?
 

Greg
I totally agree with you on the ability of engines to run under about any circumstance.. But I always wondered how friends could purchase 2 cars just alike and one would always out run, out perform, out gas mileage the other. And after many, many years of disassembling these engines , I finally understand why this can happen. Also I clearly understand now why some racers are always faster than others when both seemingly have identical setups and packages. Attention to detail, attention to stuffing the envelope, and more important than anything, the ability to think out side the box to details. Now I dont want to include the acid porting and those things, but I mean just attention to detail and ability to THINK. Look how long the first roller rocker built by Harland Sharp went until some man by the name of Jenkins figured out it was designed wrong. You know sumtin, even now at his age, he thinks outside the box. I just luv them tenna shoes and plaid pants he wears. Ridicule, no way. Man still exploring the world as he sees it.
Thanks yall for my dissertation.
PS. I would shore like to talk more about learning and thinking
reed

Re: Longer push rods ?
 

Maybe its good for us. I have the idea that if I didn't learn something today,I wasted the day. Learning isn't just for the young people.

Re: Longer push rods ?
 

Too many Greg's on here. Mr Hill may I ask a question. The .007 you saw, was that after you set your rocker arm geometry to zero or just putting a .100 long pushrod in and measuring no matter where u started.
reed

Re: Longer push rods ?
 

Setting them at zero like you do when you roll the cam to check the lift.

Re: Longer push rods ?
 

Greg
I am sorry I didnt ask the question correctly. Did you set the rocker arm geometry to zero(at half lift) before you installed the longer pushrod. I have seen variations on how much lift you get with the longer pushrod and I was trying to understand why. Sorry if I didnt make my self clear. Crap I just realized you may have answered it correctly any how. Reason I was asking I have a big block I am checking now with 2 different camshafts. One picked up .009 and the other picked up .004. I just pulled both and going to graph the lobes but even then that is a large difference between the two. have you seen that before

reed

Re: Longer push rods ?
 

Well , i tried the 100 longs and the car ,with weather conditions at Darlington has picked up about 5-7 hundreths.....Weather was nasty and humid and car ran times like it did in 70 degree weather and 1700 ft of air. it was over 90 degrees and over 3000 ft of air and way humid...I was very happy with the results and can't wait for some good cool weather...
Now looking for a few more tricks ,...?

Re: Longer push rods ?
 

Glad to hear you found something.I would like to know how a .100" long pushrod could even possibly function in a motor like that. I find that .035"-050"needs to come off most blocks, and as much as .075-.080" off most heads, thereby making most OEM pushrods about .100-125"too long already. Another variable from engine to engine is the diameter of the base circle that the cam is ground on.This can also be affected by a change in cams within a given engine. I know that my 327 could use an OEM pushrod on several valves, and a.050" short on the rest and come up close but safe on the lift. I need to re ring this engine before using it next, so after its back in the car and alive again, I'll try some closer pushrods. At any rate, we'll git 'er right. Sounds like you're on the right track as well. Good luck ahead!!

Re: Longer push rods ?
 

Glad to hear it Danny. It may be telling you that the engine can use more camshaft. Did you try raising the shift points slightly? Now that you've effectively increased the lift and possibly the duration of your camshaft (you'll have to plot it to see what you actually did) you may find you have raised the RPM where peak HP and torque occur, and may find you've also extended your useable RPM range as well.

You may also find you need to make minor tuning changes to compliment what you've found. When you make a discovery like you have, you often need to check your tune up to see if you need to make changes.

Re: Longer push rods ?
 

I usually shift at 6500 and now i shift at 6900 and still pulled good . Before it would slow at 7000 shift..
We have spring pressure low because engine was new and it ran so consistant we never raised the spring pressure to were we had originally checked at...Next i am going to to shim springs 30 and try that . I know this will help the flatness i have over 7200 .We already checked it for coil bind before when we had engine on stand. If this helps on the higher rpm ,we will then take the 538 gear out and go lower on it. I can only get a 28" tire under the rear(i guess because it is a 4-door and is very tight in the rear tire compartment. I run a 26" tire for the 1/8 and a 28" for the 1/4...I don't know if i want to try a 557 or a 586. I still need to make through the 1/4 mile.....Thank all of you for your help and suggestions as it has been a help to me.....I am thinking now in good weather it will run mid 7.50's in the 1/8 with the push rod change alone....