73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: 305chevy c-10 on December 30, 2010, 05:57:36 pm
-
is anybody ever heard of a 305 gm block that can be bored to a 350 ......i was told that u can only do this with GM blocks because they are thicker ...........he said a GM 350 block can be bored to a 406 also with plenty of of metal between cyclinder walls............if this is true how do i found these what to look for as for as markings
-
yeah, I don't think any of that is true. The blocks are all interchangeable but you can not bore them that big.
-
you can bore and stroke to increase cubes, but I don't think all of them interchange like that. I know a 350 destroked will yeild a 327 and vice versa.
-
sorry, by interchange I meant heads, motor mounts, transmissions, accessories. Not displacements.
-
Yes, motor mounts, transmissions, etc. interchange. 400 s.b. is externally balanced, where 305, 327, 350, are internally balanced. 400 heads have 2 steam holes, where others don't. Heads can interchange thou, with a modification done to fit the 400. You can use 305 heads on 350, 400, but with the small valve size of the heads, you would be hurting performance. The 305 heads can be upgraded at a great cost. All this info is about Genaration 1 s.b.c.'s.
-
to get the 406 you need to bore out a 400
-
is anybody ever heard of a 305 gm block that can be bored to a 350 ......i was told that u can only do this with GM blocks because they are thicker ...........he said a GM 350 block can be bored to a 406 also with plenty of of metal between cyclinder walls............if this is true how do i found these what to look for as for as markings
Whomever informed you of this knows nothing about Chevy motors.
-
I second that.
-
Agreed, not all SBC's are just bored and stroked differently. There are dedicated castings for the various configurations. That's why 305's go for almost nothing used, and good 350 and 400 blocks go for more.
-
got a good deal on 350 ....i think it was tpi or tbi .dont know which .......block has 638 on it with # 14093638 .......heads have 14102193 .gm24 ...guy said it came out of 93 1500 .......has to be rebuilt though .motor was outside ....some rust on piston but they move ......i will get it bored .030 or .040 depending on how bad the walls are .......does any body know about these casting # .......i was thinking of vortec heads .but i have a intake ,hei distributor already for regular heads ..........does anybody know how these 14102193 flow .......or buying a complete set will be cheaper than rebuilding these
on the rear of my block it has GM5.7LG SGI .......350 i know that much
-
wow. looks like a thought stream.
-
got a good deal on 350 ....i think it was tpi or tbi .dont know which .......block has 638 on it with # 14093638 .......heads have 14102193 .gm24 ...guy said it came out of 93 1500 .......has to be rebuilt though .motor was outside ....some rust on piston but they move ......i will get it bored .030 or .040 depending on how bad the walls are .......does any body know about these casting # .......i was thinking of vortec heads .but i have a intake ,hei distributor already for regular heads ..........does anybody know how these 14102193 flow .......or buying a complete set will be cheaper than rebuilding these
on the rear of my block it has GM5.7LG SGI .......350 i know that much
Your Block, Comes up as a 1986-94 350 The heads come up as 1986-88, 350, 1:94-1:50 EFI
-
i know that it is a 2 bolt main ...how do i tell if its 1or 2 pc rear mains .....flat or roller cam
-
google is your friend.
-
google is your friend.
It is. But so are we.
-
thanks beastie_3 ............nice to know i have support
-
We should be a last resort, I mean come on do people not bother to even try and do anything for themselves anymore? I see frigging questions like "how do I change my oil?" this place is for truck owners , but this is a simple question that doesn't need to be here.
-
Im done. Jim, I dont know what your problem is, but you have been leaving so many negative comments lately. Other people have seen it too and have sent me PMs about it. If you cant post something that helps the OP, then please dont post. We are not a last resort. A paid mechanic should be the last resort.
This place is to welcome people who have a interest in the trucks we drive or admire. We cant run them off because its easier to type google rather than putting the answer. The least you could do is tell the OP to use the search function because 1) it lets them know there is a search function, and 2) it gives them many posts that can be similar to what they are searching for.
-
well a simple question to u may not be a simple one for some else ............if u know little about motors ,then there are no stupid questions ..............i have never even seen the inside of a dismantled engine so how would i know what flat or roller cams are ...........................................further more if u don't what to answer a post intelligently ...........don't reply to them ............yeah this is a truck lovers forum .......but also its family that should help a fellow member who may not have the knowledge of a "do it your self mechanic "
-
OK since no one can search for it this is a roller cam 1 piece rear main block..
(http://image.popularhotrodding.com/f/8808599+w750+st0/0611phr_14_z+vortec_build+overhauled_block.jpg)
See the 3 little tits in the lifter valley, That is for the lifter bar hold down plate, that is the first clue its a roller cam block,
(http://www.erols.com/gcwestph/engineblock.jpg) Virtually all 1986 and up SBC blocks are rollers, You can install a flat tappet cam and GM did with almost every 87-95 tbi truck engine while the cars got roller cams and not use the roller lifters and associated hardware but with today's oils its harder and harder to keep a flat tappet cam alive and not wind up with a $50.00 oil change every time you change it because you have to either use rottela or regular oil and have to add additive to the oil everytime. Alot of folks say you don't have to , but they are running on luck and borrowed time.
This is a regular 85 and below flat tappet block which is also 2 piece rear main leak prone rear seal.
(http://www.musclecars.net/parts/parts-images-large/1970-corvette-lt1-camaro-z28-yenko-nova-chevy-350-block_370460830842.jpg)
notice the lack of the three bosses in the lifter valley, that means no roller cam unless you get a expensive aftermarket setup now 99.8 % of all flat tappet early blocks are 2 piece rear main seal but some 86 flat tappet block did get a 1 piece rear main seal. But they are kinda rare to find .mainly in trucks.
This is a 1 piece rear main seal adapter used on 87 and up engines.
(http://t0.gstatic.com/images?q=tbn:ANd9GcRuyjx15wQg9MTHv-2jf19g1Pp2Q1V3iZTPuWiHfb3N_JOsidX9)
and this is a 2 piece rear main seal block
(http://image.circletrack.com/f/9404529+w750+st0/ctrp_0712_10_z+rear_main_seal+traditional_two_piece_rear_main_seal.jpg)
You see how the seal is installed in the rear main bearing cap. Any questions.
This
-
cool...........thanks for the info ........thats why i like this forum .........this is what its all about ...........helping each other to understand ............i finished taking mine apart today .......but i can't get the lifters out ...........my rear seal is like the one with hands in the pic ....i just looked and my block has them three holes but their was no lifter hold down bar ............i know know that mine has flat tappet......but i will be rebuilt as a roller 383
-
chevy whats with the .... as spaces? j/c
-
lol..im assuming that my motor uses a long water pump reverse rot ....correct ....no water pump on it when i got it crank pulley and heads ,intake ....thinging running the cog belt set up ....has anyone done that one a 350/383
-
Only engines that run the rev rotation wp are the serpentine belt assys , The regular v belt assy's use a reg rotation WP.
-
my block had a serpentine crank pulley and no water pump
-
Excellent post right their Jim, Lot's of good information. 305Chevy, Start saving those Penny's! 383 Rollers don't come cheap. But she will be Sweet when finished ;D
-
well if you put v belts back on, use a regular water pump. If you get a serp setup. Make sure you get reverse rotation w/p and get the crank and wp pulley from the vehicle you are getting the setup from, Some vans had a stamped steel bracket that has differnt depth pulleys vs the cast aluminum bracket on most 4.3 and 305,350 's a 4.3 set will bolt on the SBC if that is all you can find.
-
got block completely apart and cleaned for tranport to machine shop .......guy told me 225.00 hot tank, bore .030 retap holes out ,new freeze plugs ,magna flux .....wow building a roller is a pricey project ....i need to save everybody pennies ..........what kind of hp difference can be gained or lost from a 377 verse 383 .....which is a 350 what?
-
a 350 what?
-
what makes a 377 ..........i was told a 350 could make a 377 instead of a 383 .....
-
never mind......did reserch ...377 not good for street ...............400 with a 350 crank .......just thought i may save from having to purchase a $700 stroker kit .......hey will the cog belt setup also use a reverse rot water pump or not .....
-
i believe it just matters what the bore size is as far as 377 vs 383. Why is a stroker not good for the street?
-
more for high rpm setups ......383's are better for street nice torque ........i was just having brain farts ......thinking a 377 would be a lot cheaper........oh yeah .jim thanks for those pics with detailed info. :).....i really learned something helpful ...............this is better than google ;D
-
I believe a 377 is a stroked 350 with stock bore. Which means if you were to bore it .030 it would be a "383"
-
305, so you think a 377 is good for high RPMs and a 383 is good for street torque?
-
Well, a 350 block with a 3.76 stroke is like 378 (on the stock bore size of 4"). Traditionally the 400 block with a 350 crank is called the 377 (.030 over the stock 4.125 bore). And yes, because of the shorter strokes and large diameter bore, people think the 377 will rev pretty high and quicker than say a 400 or a 383 with the longer crank throw. It's all in how you build the motor. The 377 will be more expensive than a 383. Plus if you've got a 400 block, build that.
-
That's right I knew it was 377or 378 but for some reason I 378 didn't look right at the time I figures it up. Lol
-
yeah its just something i read ....it basicly said a 377 is a high rpm engine
-
A 377 is the same Idea as the 327 - 350 with a 307 crank .. short stroke is all that is benefit
-
does itmatter what size rods i use in a 383 build 5.7 or 6.00
-
found the answer .....6.00 are better more power.............does anything have to be done to my block to clear a 3.75 crank.............someone said something about notching the block near oilpan for crank clearance ......i think this was refer to old 383 when people used 400 cranks and ground down the mains to fit a 350 block mains .........before aftermarket started making them ready to install
-
A friend of mine was telling me about building a 358. He used the stock 350 crank with 6 inch rods. He said it made more torque than his 383.
-
You'll probably have to grind on the block some. I did with an aftermarket crank. Both the oil pan rails and a few small parts of the block. You'll also have to notch the oil pan gasket. I recommend getting a gasket set with a one piece oil pan gasket.
5.7 vs. 6.0 I don't think is going to make a hill of beans difference for the street. In fact the 6.0 rods may add quite a bit to the price as you the pistol selection is slimmer.
-
Those 3 raised machined and tapped holes in the lifter valley do not mean it is a roller equipped engine. GM included the provisions in them all like that (86-87 up) even if they were not equipped with a roller cam. The only way to really tell if you have the roller set up is to actually see the retainer and lifters installed.
Let's help each other out or post nothing at all. K?
-
Think you are a bit late to the party, I covered the fact that the roller blocks could come and can use flat tappet cams.
-
:o
-
i know ....now .thanks to jim ......its a roller block .but had a flat tappet setup ..............they used the same block 87-95 for cars and trucks .but cars got roller setups and trucks flat setup ....roller blocks will also have 2 threaded hole on the side of the block where timing chain (cam gear) goes for a cam plate
-
so when i take my block to machine shop friday ,,,,if i tell the machinist that this gonna be a 383 ......will he know where he needs to grind for crank clearance (aftermarket crank )
-
I would give him all the parts so he can make sure everything clears. Dont want to take it back to him a 2nd time.
-
Most of the time unless he is gonna be assembling it, You will not know where to grind, You have to assemble it , find where the rods are gonna interfere with the oil pan disassemble and then grind , assemble , ect ect until you get the whole the done, then take it all apart again and then wash the block again thoroughly and clean all your parts and then assemble it for the last time, The labor to assemble it will kill you if he does it.
(http://image.carcraft.com/f/11242986+w750+st0/ccrp_0808_13_z+383_small_block+clearance.jpg)
I found this on google in .00005 seconds.
http://www.carcraft.com/techarticles/ccrp_0808_383_stroker_small_block_chevy/index.html
-
engine quest performance vortec style heads .......anybody ever heard of these #EQ-CC170BA
-
I have this engine and the # GM5.7LGSGI on the block . Does this mean it is a 350? how can i tell if it is a 4 bolt main without taking off the oil pan .