Author Topic: Pushrod length. (Read 116257 times)

shaunp · « **Reply #25 on:** January 11, 2015, 06:13:01 pm »

Quote from: skev on January 11, 2015, 04:37:09 pm

Is there a way to know how much to get them planed or will the machine shop work that out? These are second hand so I was always get them checked for true anyway.

You first need to work out what the bottom end is, calculate what you want, and most suppliers will say how many thou = 1cc from the chamber. With alloy heads you can have more compression as they are less likely to ping as the get the heat out quicker.

boofhead · « **Reply #26 on:** January 11, 2015, 11:24:32 pm »

Factory 289 had approximately between 52 and 55 cc combustion chambers. It is hard to get decent compression in a 302 while it is very hard to do it in a 289 without using specialist pistons. Flat tops just will not do it. Hence I suggest 55cc which would be around 9:1 compression which is fine for you type of build. Keep in mind the more material you take off the closer the valves get to the pistons thus increasing potential P2V issues and in some cases the intake manifold will also need to be milled to fit. Taking your 60cc heads to 55 or so should be safe on both accounts just keep it in mind than you modify one item then you often have follow on affects. Lastly, milling the heads affects the pushrod length required as well. Taking it to 55cc for a 302 will also be perfectly fine as well so in either case your sweet.

skev · « **Reply #27 on:** January 12, 2015, 08:43:33 pm »

Ok, so heads planed to 55 cc regardless of whether it turns out to be 302 or 289. Then an air gap intake. Am I likely to have any clearance issues with the intake do you think? Plus I'll probably get a carb while I'm at it. I'm in Vegas for next month so will possibly buy some parts there.

shaunp · « **Reply #28 on:** January 12, 2015, 09:05:35 pm »

Just see what's in the bottom first I reckon, ie over bore, piston type etc and work out what comp you want cause you have a choice, the more you give the better fuel you need. You could set it up to run on 98 or 95 etc. Up to you. But you'll certainly want to take some off the heads.

GLENN 70 · « **Reply #29 on:** January 12, 2015, 09:12:08 pm »

Air gap and a 570 street avenger will be a nice package .

boofhead · « **Reply #30 on:** January 12, 2015, 09:39:02 pm »

Air Gap is tall though it will fit no problem possibly using a drop base air filter.

Have fun shopping.

GLENN 70 · « **Reply #31 on:** January 12, 2015, 09:57:14 pm »

I run a RPM which is the same hight as a RPM air gap on my 66 with a std air cleaner off a 68 J code and fits no problems . A 67 should have more under hood space than a 66 .

boofhead · « **Reply #32 on:** January 12, 2015, 10:34:04 pm »

Interesting - My 65 had an Air Gap with a 670 and I had to use a Drop base. Any way, in all cases it is not a problem and fitment is not an issue.

shaunp · « **Reply #33 on:** January 12, 2015, 10:35:50 pm »

Quote from: boofhead on January 12, 2015, 10:34:04 pm

Interesting - My 65 had an Air Gap with a 670 and I had to use a Drop base. Any way, in all cases it is not a problem and fitment is not an issue.

I guess a factory air cleaner is a drop base if you think about it.

GLENN 70 · « **Reply #34 on:** January 12, 2015, 10:41:04 pm »

Yes it's a 4B drop base ,same as the 390s etc had . Open my hood and it looks stock . And guess what I have an 1 inch spacer on top of the manifold . Just fits tho with the spacer .

skev · « **Reply #35 on:** January 13, 2015, 09:17:40 am »

I just read in the installation instructions that I need to drill some steam holes in the block too.

shaunp · « **Reply #36 on:** January 13, 2015, 09:26:12 am »

Quote from: skev on January 13, 2015, 09:17:40 am

I just read in the installation instructions that I need to drill some steam holes in the block too.

Depends on the block and what year it is. you'll just need to check, Just use a gasket as a template

boofhead · « **Reply #37 on:** January 13, 2015, 11:25:20 am »

It is easy to do and necessary on an early block to run heads designed for later model engine - you will need a few new bits to make it easier to complete. I just purchase a box from Bunnings.
I have done it quite a few times. As SP suggested - I use a head gasket to locate the initial center punch holes. Then drill the holes - it will be approximately 1/2 " in to get to the water jacket. I like to use some tape on the drill bit so I know what depth I am at to gauge progress. Can be done in car - no problem. You will need to use paper (tapped up news paper I tend to use) to cover the engine so no Iron particles gets into the bores of the engine. Obviously be careful when you remove the paper and tape. Alternatively you can drill the heads though I suggest you stay with modifying the block.

skev · « **Reply #38 on:** January 13, 2015, 07:19:42 pm »

Cheers, I think I'll use masking tape over the bores to be sure.

skev · « **Reply #39 on:** January 17, 2015, 02:06:17 pm »

Good description of the process for making a hydraulic lifter solid.

http://www.allfordmustangs.com/forums/5-0l-tech/273588-how-convert-hydraulic-lifter-solid-lifter-valvetrain-measurement.html

boofhead · « **Reply #40 on:** January 17, 2015, 06:03:10 pm »

Yes that procedure works. Sometimes you need to file down the knob to get the lifter together again. You play that by ear. I have also filled them with epoxy and that works. Alternatively, I often find using very old lifters they are stuck and gummed up so rather than fight them to get them apart, just a small tack weld or two is needed so they do not move. Lazy way to do it I agree - it does work though

.

skev · « **Reply #41 on:** January 17, 2015, 09:23:55 pm »

I guess if I want to use the lifter again epoxy might not be the best option?

skev · « **Reply #42 on:** January 17, 2015, 09:25:48 pm »

Or is it best to replace the lifters? They're all working fine tho,

boofhead · « **Reply #43 on:** January 17, 2015, 11:12:29 pm »

I use old lifters that I do not intend to reuse and modify them for their future use as part of my tool kit.
As far as replacement, a roller lifters you can reuse just need to judge if they are still serviceable. While a flat tappet cannot be reused unless it is going onto the exact same lob it was initially run in against.

skev · « **Reply #44 on:** January 18, 2015, 08:11:05 am »

Cheers, ill try and find a lifter somewhere

GLENN 70 · « **Reply #45 on:** January 18, 2015, 09:32:07 am »

Just go get a new lifter from repo etc . Most of the 60 and 70s ford v8 and 6 cyl lifters were the same . You should be able to buy just one and they are cheap as chips under $10 max . Even one out of a 302/351c. Is the same .

skev · « **Reply #46 on:** January 20, 2015, 07:38:55 pm »

Thanks, good . Got the 570 in Vegas today, just need to get the airgap intake and associated bits and pieces now.

skev · « **Reply #47 on:** January 29, 2015, 06:05:53 am »

Think I have settled on the Weiand Action Plus due more torque lower down. Should I used stepped bolts for the head or bushes?

boofhead · « **Reply #48 on:** January 29, 2015, 07:45:44 am »

Either works.

shaunp · « **Reply #49 on:** January 29, 2015, 05:47:52 pm »

Quote from: skev on January 29, 2015, 06:05:53 am

Think I have settled on the Weiand Action Plus due more torque lower down. Should I used stepped bolts for the head or bushes?

If you are buying ARP just get the bolts if reusing old bolts get the washers.

Pushrod length.

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Author Topic: Pushrod length. (Read 116257 times)