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360 to 408

You can build a 904 to be really stout. The parts can get expensive depending on how much power you want it to handle. But it's lighter, takes less power and front drum is safer then a stock 727.
i have heard this as well. It seems like stock the 727 takes more power and is more reliable, but built the 904s can get done cheaper and handle alot of power. This is going to be a semi budget build, just trying to find decent deals as i go buying wheat i can when i can. so to start off it will be linked up to my stock 904. just depends what i find i guess.
 
Pretty sure a 1990 would have been a roller cam engine originally.
I'm not a small block guy but I think the lifter bores/ casting are taller than the older la engines to support the roller lifters.
Hopefully someone more knowledgeable than me on small blocks can chime in.
hmmm well this seems fine to me hahahah. like i said first engine build and i hear horror stories about stuff going wrong during flat tappet break ins, so i want to be as bulletproof as possible. i want least wear and more durability out of parts i get. thats why im looking for roller cam, roller rockers etc.
 
Spend the money on steel or s/s rockers.. You will sleep better.....
yes this seems to be the general consensus that they are much beefier than the aluminum stuff, so this seems like the way im going to go. I found a set that is stainless steel from speedmaster, i think im going to try giving those a shot.
 
I believe you are correct, and i don't even know if a downgrade is even possible in in
that block regarding cam choice. Others can advise.
this would probable be something my machine shop would be able to confirm right?
 
Think it’s been a dozen or so years ago, when I was just getting going on restoring my car and I found a guy selling 340s on ebag.
It happened that the guy lived in the same town as mine and I went by his house to talk. He was telling me that the 340 blocks were getting more expensive and he told me he had a 360 in really good shape. He told me that the bang for the buck on this motor was probably what I wanted. He had a set of heads for the 360. I asked him if my 318 heads would work. He told me that yes they would, maybe even get a little more out of it after he ported them. So that’s what we did, solid lifters, slightly aggressive cam, Thermoquad and he threw in a set of headers. I had my 904 tranny rebuilt with a shift kit. The motor is all I need and I only really got on it one time and I squished a motor mount. I’m not by any means an expert on this, but I know it works for me. Maybe someone will chime in on this.
i do have a set of pretty beat 318 heads hahahha. this may be an option if i cant find anything else. Do you remember what you needed to hook the 360 to the 904? its internally balanced. so i know my dampener needs to be a 0/ neutral balance. i also need to get a flywheel because i dont have one. will i need a weighted flexplate? a flex plate at all? what kind of converter do i need? these are the sort of questions im running into trying to get a picture for the future on what ill need. i hear alot of people say that they got a shift kit put into a 904 and thats how they built it/ is that all that it takes to beef a trans? i really dont know anything about trans so dont really know what it would entail making sure my trans was up to the task of the 408 if thats the route i wanted to go.
 
yes this seems to be the general consensus that they are much beefier than the aluminum stuff, so this seems like the way im going to go. I found a set that is stainless steel from speedmaster, i think im going to try giving those a shot.
However, I'd highly suggest the rockers be at least bushed.
 
I suggest you don't consider rocker arms from speedmaster, especially if you are wanting something dependable, you get what you pay for in most cases. Cheapest adj rocker you can find is likely a used adjustable set off a 273. Offerings of Mancini or Hughes are better choices.
This does not sound like a race engine. Pretty much building a freshened 904 w stock internals should work with a shift kit to increase valve body pressures and clean up the shifts. Since you will have a internally balanced engine you can use a 318/340 flex plate and convertor.
 
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I suggest you don't consider rocker arms from speedmaster, especially if you are wanting something dependable, you get what you pay for in most cases. Cheapest adj rocker you can find is likely a used set off a 273. Offerings of Mancini or Hughes are better choices.
This does not sound like a race engine. Pretty much building a freshened 904 w stock internals should work with a shift kit to increase valve body pressures and clean up the shifts. Since you will have a internally balanced engine you can use a 318/340 flex plate and convertor.
this will absolutly not be a race engine hahaha. i baby the car for the most part. that may be because of the dorky 318 thats in it though, but the most the new engine will really see are a few street pulls and maybe a few burnouts. When you say 318/340 flexplate why? would i not get a 360 flexplate? does it need to be weighted or neutral? ive heard people talk about a b&m flexplate for a 360 to go onto a 318 that was previously hooked to a 904. but since im balancing internally im unsure if ill need that or not.
 
this will absolutly not be a race engine hahaha. i baby the car for the most part. that may be because of the dorky 318 thats in it though, but the most the new engine will really see are a few street pulls and maybe a few burnouts. When you say 318/340 flexplate why? would i not get a 360 flexplate? does it need to be weighted or neutral? ive heard people talk about a b&m flexplate for a 360 to go onto a 318 that was previously hooked to a 904. but since im balancing internally im unsure if ill need that or not.
Yep, a oem 360 flex plate would work fine, or just use the one off your 318. The best survival of a 904 would be to put new clutch seals in it, if it hasn't been overhauled recently. When you turn the pressure up in a shift kit, the old seals are the first to go and you will burn up a clutch pack. A 727 certainly is stronger then a 904, but a built 904 is very stout.
 
Yep, a oem 360 flex plate would work fine, or just use the one of your 318. The best survival of a 904 would be to put new clutch seals in it. When you turn the pressure up in a shift kit, the old seals are the first to go and you will burn up a clutch pack. A 727 certainly is stronger then a 904, but a built 904 is very stout.
so the flex plate from my 318 would work? behind a 360 thats swapped to a 408? and what about converter would i need to change that?
 
Just use the 318 convertor...the 318 and 408 are both internally balanced.

If you were to buy a new convertor. There is a stronger convertor hub that can be used on 904 race convertors, and they run a wider front pump gear in the front pump. But, I don't see a need for it here, unless you suddenly decide you want big horsepower.Lol
You are correct..don't use a aftermarket externally balanced 360 flexplate for your new internally balanced 408. The damper should not be externally balanced either.
 
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Just use the 318 convertor...the 318 and 408 are both internally balanced.

If you were to buy a new convertor. There is a stronger convertor hub that can be used on 904 race convertors, and they run a wider front pump gear in the front pump. But, I don't see a need for it here, unless you suddenly decide you want big horsepower.Lol
You are correct..don't use a aftermarket externally balanced 360 flexplate for your new internally balanced 408. The damper should not be externally balanced either.
Great information. Thank you
 
Those rockers are bushed, but I don't see a shim set for centering the rockers. You will need to get a geometry kit from Mike B3 Racing. New pushrods. You may have to work on the sides of your intake valley to clear your roller tappets. Just my opinion of course, but you should be going through one source for all of this. Buying parts here and there and then finding out that all or some of them are incompatible with each other. I realize that you may or may not be trying to learn, people will lead you over to the edge of the road, but not tell you that there is a one thousand foot cliff at its edge. Just be carefull, you have already started across the road. Well, I got this block and have a balanced rotating assy.
Hope this all turns out well for you.
 
Those rockers are bushed, but I don't see a shim set for centering the rockers. You will need to get a geometry kit from Mike B3 Racing. New pushrods. You may have to work on the sides of your intake valley to clear your roller tappets. Just my opinion of course, but you should be going through one source for all of this. Buying parts here and there and then finding out that all or some of them are incompatible with each other. I realize that you may or may not be trying to learn, people will lead you over to the edge of the road, but not tell you that there is a one thousand foot cliff at its edge. Just be carefull, you have already started across the road. Well, I got this block and have a balanced rotating assy.
Hope this all turns out well for you.
yes im trying to use jegs for most of the stuff, they have great customer service/support. or do you mean like one brand? in which case that would be much harder to do i think. Yes i know that im trying to do as much research as possible before pulling the trigger on any one thing or another. Trying to figure what will work with the parts i already have and the parts i want. bit overwhelming but it comes with the territory of doing anything for the first time.
 
Well, Jegs or Summit would not be my first choice. You can get parts there, but it's not necessarily the hands on guidance that I am referring to. For instance, when I built my stroker, after seeing countless people like yourself go down the worm hole, I called one person up, told him what I wanted to do and then bought all of my parts from him because he took the time out of his working day to give me advice. I did that because he builds them and knew exactly what would and wouldn't work. Not a bunch of mismatched parts. There was a saying back when I built an airplane, " No free lunch". Free advice isn't always free, there are a lot of curves in the road!
Will pm you with a name.
Sorry for the rant guys, it is what it is.
 
Well, Jegs or Summit would not be my first choice. You can get parts there, but it's not necessarily the hands on guidance that I am referring to. For instance, when I built my stroker, after seeing countless people like yourself go down the worm hole, I called one person up, told him what I wanted to do and then bought all of my parts from him because he took the time out of his working day to give me advice. I did that because he builds them and knew exactly what would and wouldn't work. Not a bunch of mismatched parts. There was a saying back when I built an airplane, " No free lunch". Free advice isn't always free, there are a lot of curves in the road!
Will pm you with a name.
Sorry for the rant guys, it is what it is.
Not a rant at all. Its sound advice and that's exactly why I'm here. For good advice and to maybe get a little wisdom from some people who know more and have already done what I'm trying to piece together hahaha. These questions are aimed so that I don't do exactly that, spend a bunch of time or money on parts that will not work for my application or do not benefit my application or even do not work with other parts I'm looking to buy. I appreciate all the help you all have/are supplying and thank you all for the continued support.
 
Just some observations:
1) That is an early LA block and will require pushrods open for oil from the lifters for Magnum heads as Magnum engines don't thru the block deck
2) The lifters will require the link to prevent rotating in the bore
3) A retro fit roller cam will need to be used for the OE timing set, or a roller timing set for a regular roller cam (the cam gear will be different). Others can comment as to teh application.
4) I am doing a '94 roller 318 and the cam woodruff key is shorter that the regular one, ~5/8" x 3/16" Dealer purchase might be easier
 
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