304 performance upgrade advise

F

FerDili

New member
Hi everyone ,
im fernando from argentina , new to this formum so hope im posting in the right place . I have a couple of scouts one 1977 with 304 and torqueflite 727 and the other one a 1974 that I got with no engine or transmission .
I have some experience with chevrolet or Ford v8s from standard to mild performance engines , but this is my first time with an International so I will appreciete a lot your advise
the 304 has 137k miles , is the one that came with the Scout and never opened . The lifters are a little noisy when cold , then it s better but definitely need to be changed .
Now my idea is to take the opportunity to make some changes to improve performance.
4 barrel carburetor together with intake , electronic ignition and a first stage cam that can improve torque .
Finally the bottom end seems to be in good condition so I May skip a full rebuild this time . But in any case I would like to know what pistons do you suggest flat or contour ? And what is the final compression ratio that results from each ?
Ok , its a lot of info im asking , thanks for reading and hope to receive your feedback
 
Be kool,, an old saying " pump up the top & blow out the bottom " ! You don't wanta 4 brl.on it. If so, then change to a 345.
 
First off IH never made a 4 barrel manifold for the 304, so you're stuck there. Lifter rattle on cold start is normal. So don't worry about that.

All that said, I built a 345 a while back. It's bored .020 over with silvolite pistons, a 4 barrel 390cfm Holley, comp 252 cam, 9:1 cr and stan's headers. It runs strong and will occasionally get 15mpg on a tank of gas. The silvolite pistons are industrial, not performance parts so they keep the steel first ring land and are not good for over 5k rpm.

You want to have around a .045" quench area, so due to the thicker composite head gaskets (.040 vs. .016) the block was decked and the heads were shaved.
 
Thanks for the comments
well , you have to consider that having a Scout down here is not a common thing , as far as my group of offroad friends know there are only 3 scoutii and 1 800 that we know . I have 2 of them so there s not much experiences to share around here .
Unless I import a 345 from us I will have to stay with my 304 , after some reading I know that the 304 is a good engine and there s no factory 4 barrel intakes .
From my experience with other v8s that were slightly improved with a cam , ingnition and exhaust a 4 barrel gives better tunning and performace .
I saw theres a 4bbl intake for 304 on ebay and another online store .
But what about pistons and compression ratio . Does anyone kow what s the factory compression ratio? Then what about flat top or contour pistons?
 
If you want parts for your 304, call IH Parts America (530)274-1795 for we May have all the performance stuff you need. And you want more performance out of your 304, well that's kind of hard. I've heard of people boring out the cylinders to fit standard 392 pistons, but all that work isn't necessary for a 304. And we have 345's here if you want any(cores, long blocks, or complete engines). Thanks and good luck.
 
The most likely place to find a 345 is in a loadstar truck. Any of those in those parts? There were a few after market 4 bbl manifolds made. I don't know the quality though. Flat top pistons with the heads on the e series. You should have an e series engine. There should be a 304e stamped on the boss above the fuel pump. You will need a mirror to see it. The difference between a 304 and 345 is 1/2" more deck height.
 
Don't be afraid to stick a 392 in your sii if you can snag one out of an old school bus or flatbed truck etc. A common saying here in the states is, there's no replacement for displacement. In terms of IH engines, that really is the cheapest and easiest way to gain performance. Go big or go home. These aren't race motors. International is also known as a 13 letter shit spreader. If you really can't stand to drive your Scout unless it makes over 300hp, you better be looking at small block Chevy or big block mopar swaps. Other than that, tune it up well, polish the exhaust ports, fuel inject it and enjoy your 160 brake horse power engine for what it is.
 
Hi, thanks for your comments , I now get the idea what kind of engine this is .
About finding a 345 or 392 , International was or is not popular in argentina , just a couple of scouts brought by owners that moved down here and some big trucks imported by companies . I ve been checking through some contacts but no positive info , so I will work on my 304 that will do fine optimizing a few things , just for the fun of doing something.
First of all , May be you can confirm a few data , I belive the 304 weights at least 100lbs more than a similar displacement engine like a sb Chevy for example , is it correct ?? Then my engine numbers are the following v 304 a and no 235687 . If there s interesting information from those numbers I will appreciate you can tell me .
Now going to my plan , the idea is to install a 500 cfm edelbrok carb with an aftermarket 4bbl intake , do some work to the heads , change headers and exhaust , 252 or 260 grind cam and electronic ignition.
What do you think ?? Any comment on the cam?
 
Yes on the 100lb extra weight. 304a means it was the light duty one, so no hardened valve seat inserts along with a few other things. This is an industrial engine that really should not be run much above 5500 rpms. The pistons have steel inserts on the first ring and the valve lifters are big and heavy which limits you rpms but makes it live for a long time with the throttle wide open on a truck.

The 500cfm edlebrock will work, but you'll rarely ever get into the secondaries. IH put a 390cfm Holley on the 392, so thats what I went with on my 345. Stan's makes great headers that fit well. The exhaust ports are very restrictive on these engines. If you have the heads with bosses cast into them for air injection, get some set screws to fill the holes and grind the bumps out of the ports at the very least.

Keep us informed! Some pics with argentinian scenery would be interesting.
 
Hi , thanks for the comments and advise .
I agree 5000 rpm is the top , so I guess the 252 grind will give the extra breathing plus the work on the heads , headers , etc will be more than enough .
I bought the Scout in 2011 from and old man who came back from the us , he was the first and only owner as he said , but as I have no way to prove it we ll have to trust his words. Anyway the Scout is in excellent condition for a 40 year old truck so if it is not 100% true it is very close .
Unfortunately I dont have much time left for my hobbie , due to work and family and as I have other vehicles , my Scout rested in the garage since 2011.
Now its his turn so ive finished servicing the brakes , steering and suspension , which I lifted 3 inches , from where it was . As I cannot compare .
Here s my Scout in buenos aires , argentina SCOUT.jpg

This picture was taken a few weeks ago befor I started working on it
 
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