im looking at a 87 iroc, 5 spd, 305 tpi... but the block is toasted.

the kid im getting it from has a block with casting # 14010209, says its a 2-4 bolt main 350. flat top pistons with the groove for the valves (looks like the 89 style 350 pistons, no dish) but its clearly a flat tappet cam... no roller. 80-85 350 block. (anyone know what the compression ratio is on that block#?)

i want to put 350 heads and the 305 TPI top end on the pre 85 block... will that work??

i have a pcm/ecu for a 87 iroc 350 auto. can i use that ecm with the 5 spd wire harness and stick or would i need to swap/ reprogram the ecu to run the 350 vs 305?

if all else fails i will just find a 305 roller block and bring the car back to stock form, but i get a 350 block with the deal and all the parts to build a 350. so if i can do that i will.

thanks in d

 

Newer heads will work fine on the older block. I'm not aware of anything from that era coming stock with flat top pistons though. Make sure you know what you're getting.

87+ heads & intakes changed the bolt angle, but the intake holes can usually be elongated to work, though getting the intake that matches the heads would be best.

As for the computer, you should probably invest in a custom tune. The 5 speed cars had a very different tune than the auto cars. The lack of a manual trans 350 means thete aren't any stock tunes that are appropriate.

 

i think the motor may have had some work done to it then because the pistons in the block 14010209 that im looking at look just like the pistons that are in the L98 350s... or at least similar enough.

the deal with this car goes as follows...

someone took 350 and made a 383 with heads and all that and put it in the car with the t-5 and it apparently ran like a beast. until it threw a rod through the block.

so after the engine blew he tore it down and put everything in boxes, minus the block and the crank (which is still in the engine bay) and put it all inside the car and shut the door and there it sat for 2 years.

so now he is selling the car and the contents in it, as well as this 350 block #14010209 that has pistons like a L98.

is there any way to tell if the ecu has been tuned or reprogrammed by looking at it? in the off chance someone went through the trouble of doing a 383 TPI stick tune... off chance, but if the car most recently ran like that Im willing to try.




i was just checking out your car domain page and i love the mods,your kick panel speakers are off the chain! I also laughed because those old pics of your car when you first got it. the one im looking at has the same dent one the drivers fender and door.

 

You better not try 081 heads on a flat-top 350, you'll be close to 11.5:1

 

BLOCKS don't "have" compression ratio.

The only effect the block itself has on CR, is "deck clearance" variation. No one block casting is likely to have that any different than any other, although in general, newer blocks have less variability in their processing.

The COMBINATION of block, crank, rods, pistons, heads, and gaskets, is required to be known before compression ratio can be determined.

If the pistons REALLY ARE flat tops with typical 4-eyebrow valve reliefs, then if you measure the AS-BUILT deck clearance (bring a piston to TDC, measure how far "down in the hole" it is, expect something in the .040" - .050" range) and the stroke (bring it to BDC and see how far it went down from TDC) then we can estimate what the CR will be with any given gasket thickness and chamber volume. Any "calculator" you find anywhere will give the same results, just like any calculator you find on the shelf at Wal-Mart will add up 2 + 2 and get 4 the same as one costing 20 times as much from an engineering supply kind of place, if fed the same input numbers; so don't bother with "I'm using such and such 'calculator' and it says... " until and unless you have ACCURATELY MEASURED the parts in question.

 

Ok, the pistons have the eyebrows. I assume the the crank and connecting rods are not modified. I was told the block had a cam in it as well. Any way to check that with out pulling it out?

Also I was looking at the 081 heads (says they are for a 305 online) and the rocker arm springs look like there are some other blue and yellow springs inside the main ones. Is this stock or some sort of spring assist?

And can I use center bolt heads on a non roller cam block using the push rods and all that or are they a different length?

 

Pushrod length relates to the cam type ( flat tappet or roller cam) independent of block or rockers.
Roller cam lifters are longer so pushrods to suit must be shorter than flat tappet pushrods

Any Gen 1 SBC head fits any Gen1 SBC block ; afore mentioned provisos about CR not withstanding

 

You can kinda look down in there and see if there's one there.

In that pic, blue = the valve guids seal; yellow = the damper (part of the spring). Looks like the springs have been replaced but hard to say whether they're "stock" or not. Probably at least close to it; anybody that would put better ones on and actually know what they're doing, would have left off those worthless dead-weight non-functional oil spash shields.

Don't do that. Break the word down into its 3 component parts to learn its true meaning: 3 letters, 1 letter, 2 letters; "makes an {3 letters} out of {1 letter} and {2 letters}". Absolutely positively THE WORST THING you can POSSIBLY do when building an engine. Assume NOTHING, measure EVERYTHING. Furthermore, if you can't SEE it with your own eyes, IT DOESN'T EXIST, no matter how passionately the PO drivels about it, no matter how bad you want it, no matter how great it sounds, no matter no matter no matter no matter. That is Law #1 of buying used cars or parts.