rebuilding 351w..

[rebel65]

hey
i just got a 351w and it's all taken apart the pervious owner threw a piston ring and ive dealt with problems like this multiple times on one of my dad's porsche engines and shouldn't be a big deal but...i feel really stupid and the search function isn't working.

i need to take it to a machine shop to get it bored whatever over. and i am just curious what i need to tell them to do.

from the last time i built an engine it was put in an 'acid bath' and magnafluxed and leak down tested?? i don't know exactly what this is, but for some reason this is the one part of engine building i haven't ever expirienced. so i come to you all with such information. my plan is to get some forged 8:1 comp pistons hopefully stroke it a little max 383. this is going to be a street car so. my future ideas call for a supercharger then when i'm 40 and need direction in my life will go Turbo lol. but yea..


what do i tell a machine shop, and after how will i know what size pistons/rings ect to get? only time i've built an engine was in an auto class where everything was already provided.

Thanks, sorry but once again the search function did not work...

 

[70MachI]

Acid Bat: Is were the machine shop puts the parts in a machine that has a chemical that eats the grime away, so they have a clean block to work with.

Magnaflux: Its a were the machine shop uses to determine if there are stress cracks.

Leak down test:Tests how long either the cylinder head keeps pressure before it leaks out of the valves or how long the piston rings hold pressure in the cylinder.

Also to get 8:1 compression on a 383 stroker is going to be hard to do without custom pistons.Why do you want it so low? Get something in the mid to high 8s. Have you looked at any pre assembled short blocks? Also ask the machine shop what you need. Most of the time the machine shop will want to work with you in buying parts that will work for a certain combination. If they do not, Walk away from that machine shop and find one that will work with you. Believe me, you want a machinist and engine builder that WANTS your business and is willing to help you.

 

[65ShelbyClone]

1.)from the last time i built an engine it was put in an 'acid bath' and magnafluxed and leak down tested?? i don't know exactly what this is, but for some reason this is the one part of engine building i haven't ever expirienced. so i come to you all with such information.

2.)my plan is to get some forged 8:1 comp pistons hopefully stroke it a little max 383. this is going to be a street car so. my future ideas call for a supercharger then when i'm 40 and need direction in my life will go Turbo lol. but yea..

3.)what do i tell a machine shop, and after how will i know what size pistons/rings ect to get? only time i've built an engine was in an auto class where everything was already provided.

1.) "Acid bath" is the same as hot tanking; the block is dipped into a heated acid bath that strips everything off the block. So much so that the cam bearings must be replaced if the block is hot tanked. Hot tanking is almost standard for many engine shops.

2.) With a 393 crank, 351W rods, and 302 pistons you'll have a 393..... If you can find 302 pistons dished enough for 8.5:1.

3.) It really, really helps if you can take measurements yourself, but that usually involved a couple hundred bucks worth of inpection equipment. Your block will most likely need a .030 inch overbore, matching rings, and the connecting rods resized.

To be honest, I'm not sure you're ready to assemble this yourself. I would suggest much more reading before you make a big monetary decision on the engine.

 

[rebel65]

thanks for your input and to tell you the truth i more than half agree with you. which is why i'm here..i know i might not sound like i know very much but i can feign knowledge sometimes. i am more than able to assemble an engine i just have never gone from a used block. and i do have some more research to do on components. you're right thanks i hope to show you my engine soon .

 

[65ShelbyClone]

I hope it sounded more like a constructive suggestion than a put down. I forgot you've worked on Porches before.

If you have a pair of good 6" calipers or know someone who does, you can get an idea of what needs to be done to the bores and crank. If the bores are worn, but still less than 4.030", then it's a standard bore block and you can get a .030" overbore. If you get a stroker, you'll get a new crankshaftanyway, so you'll need standard rod and crank bearings.

There's not much to it unless I've forgotten something. I bought my roller 302 from P.A.W. as an unassembled kit, so it was pretty easy.

 

[Max Power]

Get these two books:

http://www.amazon.com/gp/product/18...102-4485030-4008954?s=books&v=glance&n=283155

http://www.amazon.com/gp/product/19...5030-4008954?_encoding=UTF8&v=glance&n=283155

 

[rebel65]

thanks, i took it as nothing more than what it was 65clone i understand with the words i put in there i could not be percieved very well lol. anyway thanks for the book suggestions MAX, i'll read the second one, i'm still unsure if i am going to stroke it at all..

i'm trying to find a kit for the pistons and rods i am thinking forged 5140 rods and some notched or dished pistons of sorts..but i don't know where to look to get 'em. i've seen coast high perf, and summit seems to be severely lacking on the 351w front. any suggestions? ( possibly not the gold plated route if you know what i mean )

 

[jerry S]

summit seems to be severely lacking on the 351w front.

I have a 420 hp 351W and everything used to build that engine (rods, pistons, rings, bolts, oil pan, windage tray, cylinder heads, headers, mufflers, intake, carb, air filter, water pump, fuel pump, pulleys, radiator, fan, transmission cooler, etc, all came from summit.

the only things you cannot get from Summit are Barry Grant carbs and AFR heads.

 

[rebel65]

I have a 420 hp 351W and everything used to build that engine (rods, pistons, rings, bolts, oil pan, windage tray, cylinder heads, headers, mufflers, intake, carb, air filter, water pump, fuel pump, pulleys, radiator, fan, transmission cooler, etc, all came from summit.

the only things you cannot get from Summit are Barry Grant carbs and AFR heads.

sorry for not being clear on that. i can definatly find everything i need from summit. what i am saying is i can't find any kits. i just need to ***plan*** this all out is my problem lol. btw, MAX i ordered that book, minus the big inch fords book, i think the second one will serve my needs a lot better. thanks.

 

[jerry S]

sorry for not being clear on that. i can definatly find everything i need from summit. what i am saying is i can't find any kits. i just need to ***plan*** this all out is my problem lol. btw, MAX i ordered that book, minus the big inch fords book, i think the second one will serve my needs a lot better. thanks.

The only kits they sell are stroker kits. For the rest, you have to choose your components yourself. Dyno200 will allow you to get the theoretical outputs of different components. Find the output and powerband you like and get those components.

Speedomotive sells non-stroker rotating assemblies but you can find everything at summit.

 

[D.Hearne]

You also need to remember that Summit doesn't list all the parts, kits, etc in their catalog. If you don't see it, call and ask.

 

[dennis112]

You also need to remember that Summit doesn't list all the parts, kits, etc in their catalog. If you don't see it, call and ask.

Correct!

Off topic, but I called Summit to place an order for a Tru Trac and asked if they could get 31 spline axles for my Stang. I told them the manufacturers part # I was interested in and to my surprise, they were in stock and shipped the same day. These parts were not listed in the paper nor on-line catalog.

 

[rebel65]

right i do forget the fact that they are a giant warehouse.

so 2 questions...is a cast steel crank good enough? because i've found a 383 kit i deem affordable and strong enough for my application, but the only question i have is the crank. should i fork the biggies for a forged crank? I AM going to put forced induction on this once it's in the car. 2psi or 10 i want to make sure it doesn't fold under the pressure on the ONE point that is weakest. aka the only thing non forged in the engine will be the crank. is that okay?
if so i'll be calling Summit to swap that crank out for a forged one. thanks for all your help so far. that book should show up tomorrow or tuesday, now i have to focus on the valve train...

i'm planning on calling comp or crane and figuring out what i need. but i want a hydrallic roller setup. should i plan on anything special when i talk to them?


my plan so far.
383w Eagle stuffs ( 5140 i beams, dished +24cc forged pistons )
351w heads ( someday vic jrs? )
hyd roller valvetrain
torker II or Vic JR.. ( should i keep my RPM Airgap?? even with a supercharger? i am all about street manners not 7000 rpm pulls )
750 holley blow through carb.


centrifugal supercharger pushing 4-10 psi don't know yet, it will all depend on the power i get.

should i keep the Air Gap?i love torque...a lot, but i do want the good 'ol civic eatin on the highway...soooo you know

 

[D.Hearne]

If you'e not going to see higher rpms, I don't see why you'd get rid of the Airgap.

 

[Max Power]

right i do forget the fact that they are a giant warehouse.

LOL...actually, THREE giant warehouses.

 

[rebel65]

HEHE 3....that's sexy... yea D.H. That's why i asked...just making sure there wasn't something i didn't know. hehe i love it when my project gets simpler... that book should come today if not tomorrow..should be getting the block prepped today..Anyway THANKS for all the help peeps.