Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (http://www.hotrodders.com/forum/)
-   Hotrodding Basics (http://www.hotrodders.com/forum/hotrodding-basics/)
-   -   LT1 rotating assy into a Vortec 5.7 block opinions (http://www.hotrodders.com/forum/lt1-rotating-assy-into-vortec-5-7-block-opinions-214109.html)

Jim Rockford 02-06-2012 10:39 AM

LT1 rotating assy into a Vortec 5.7 block opinions
 
Just picked up a(nother) sweet 77 impala coupe. has a decent running 305 2 brl engine in it now,but I'm looking do do a budget 350 i have a vortec 350 short block that has a bad bottom end, haven't pulled the pan yet to see if It can be saved, but I also have a very low mileage lt1 that came out of a road master with an electrical fire, few burn sensors , but that all, wondering about installing the pistons rods and crank into the vortec block and topping it with a set of l98 heads I have laying around and a used edelbrock performer .. What do you guys think...?
any thoughts on a good roller cam?
http://img.photobucket.com/albums/v1...a/IMG_1234.jpg

DoubleVision 02-06-2012 11:36 AM

What are you looking for in a roller cam? Low end torque? Mid range?
Swapping the parts over from the LT1 bottom end to the Vortec should work out okay. Not sure what style pistons the LT1 engines use, but since the L98 heads have such a small chamber you'll have to keep a close eye on the compression ratio. I have a roller cam for sale that I used in my Vortec engine. It has less than 2000 miles on it and in excellent shape, it would save you a few bucks compared to buying a new one. Shoot me a PM if your interested. Not sure if you know also but Vortec blocks require a special timing chain so I'll include it in a link:
http://www.summitracing.com/parts/CL...n/?prefilter=0

Jim Rockford 02-06-2012 12:14 PM

Well the L98 heads I have are Iron 64cc heads, the vortec engine has dished pistons and the LT1 has flat tops...but the LT 1 heads are 64 cc to I think ..I have both the roller LT1 and the Vortec cams and I think I have a roller cam from a l98 also , Just looking mainly for low and mid range power.

DoubleVision 02-06-2012 02:54 PM

The cam I have is a comp cams magnum .206 duration @.050 and .500 lift.
It's designed for low end torque and fuel economy.

Jim Rockford 02-07-2012 10:15 AM

Was it that bad of an idea?

DoubleVision 02-07-2012 11:24 AM

Not a bad idea at all, nobody is replying as you seem to already have all your answers. You know the parts will work, what else would you like to know?

Jim Rockford 02-07-2012 01:37 PM

Mainly wondering if I would gain anything from useing the flat tops from the LT1 along with having the shorter piston skirt, over the dished vortec pistons? Opened up the bottom of the vortec today and found the crank broken between the #7 rod and the 4th main web.
http://img.photobucket.com/albums/v1...0/IMG_1243.jpg
http://img.photobucket.com/albums/v1...0/IMG_1244.jpg
http://img.photobucket.com/albums/v1...0/IMG_1246.jpg
http://img.photobucket.com/albums/v1...0/IMG_1248.jpg

cobalt327 02-07-2012 02:32 PM

Whether to use the FT or dished pistons comes down to simply entering the numbers (rod length, intake valve closing point and SCR) into a calculator to see if the DCR (using the cam(s) you have on hand) falls into the range of pump gas or not.

Personally, I'd spec the cam to work w/the heads and the LT1 FT pistons- even if it means buying another cam. The advantages in the quench/turbulence created by true FT pistons shouldn't be discounted. If you need more chamber volume, work the chambers to deshroud the valves and gain volume. It's not that the valves are shrouded w/1.94" intakes, but the idea is to get some benefit other than just enlarging the chambers if possible.

ap72 02-07-2012 04:05 PM

I would plan on getting that block line honed. Its pretty easy to open up the area arou.d the valves and gain airflow and drop compression as Cobalt said, its a win win in this case.

Jim Rockford 02-07-2012 04:20 PM

Sounds like a plan thanks fellas. I'll prolly just use the B body LT1 cam or a truck cam, have to do some checking I know they are really close if not exactly the same.

onlyfnway 02-07-2012 10:40 PM

If i am not mistaken the lt1 cam does not have a gear for the dist. being it is driven off the front of the engine. Lt1 heads should be 58cc?

ap72 02-08-2012 08:37 AM

Quote:

Originally Posted by onlyfnway
If i am not mistaken the lt1 cam does not have a gear for the dist. being it is driven off the front of the engine. Lt1 heads should be 58cc?

The oil pump is still driven off of the rear, the gear is there.

louis165 02-08-2012 08:49 AM

Quote:

Originally Posted by Jim Rockford
Mainly wondering if I would gain anything from useing the flat tops from the LT1 along with having the shorter piston skirt, over the dished vortec pistons? Opened up the bottom of the vortec today and found the crank broken between the #7 rod and the 4th main web.
http://img.photobucket.com/albums/v1...0/IMG_1243.jpg
http://img.photobucket.com/albums/v1...0/IMG_1244.jpg
http://img.photobucket.com/albums/v1...0/IMG_1246.jpg
http://img.photobucket.com/albums/v1...0/IMG_1248.jpg

Jim you wouldn't by any chance know the cc of the vortec dish piston would you?

Jim Rockford 02-08-2012 09:53 AM

Quote:

Originally Posted by onlyfnway
If i am not mistaken the lt1 cam does not have a gear for the dist. being it is driven off the front of the engine. Lt1 heads should be 58cc?

You are thinking of the LS series engines,,
the LT1 has a stuby shaft that sits under the intake
http://image.popularhotrodding.com/f...k_package+.jpg
Quote:

Originally Posted by louis165
Jim you wouldn't by any chance know the cc of the vortec dish piston would you?

What I found on the Interwebs..
Quote:

I measured the dish and found that they are 10.5 CCs, and they are .028" in the hole. I was trying to decide if not changing pistons was going to cost me too much power vs. how much money it would cost to change them.

louis165 02-08-2012 10:46 AM

Jim thanks I've been trying to find these numbers for a while now I'm using the vortec block with dish pistons I didn't know any better and used 041 head gaskets with stock deck hight 9.025 put me with 66 quench not good ! Now that you have helped me out I can take it back apart an change head gaskets 015 or 020 thanks


All times are GMT -6. The time now is 03:19 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.