Has anyone put a S block in a S4?
03-22-2006, 01:14 PM
#1
Addict
Rennlist Member
Rennlist Member
Thread Starter
Join Date: Dec 2003
Location: Houma, LA.
Posts: 546
Likes: 0
Received 0 Likes
on
0 Posts
Has anyone put a S block in a S4?
I'm looking into my options. As most of you know my 1990 S4 block is cracked. I have been looking at what's avaiable and trying to decide the best way to go. That is weighing out cost and correctness (if you know what I mean). I know that the S block doesn't have the knock sensors. How big is that issue? Is there a work around? What other issues would I run into?
03-22-2006, 02:06 PM
#2
Drifting
i would have thought that another S4 block is about the only thing to do. i know that at the very least the S engines have different sized cylinders, beyond that im not sure the later heads can be mated to them in any kind of straightforward fashion. if your talking a complete engine swap, heads and all then that is probably possible but you will probably want to change the ecu and harness as well.
03-22-2006, 02:56 PM
#3
Burning Brakes
Join Date: Oct 2004
Location: Suburban St. Louis in Illinois.
Posts: 877
Likes: 0
Received 1 Like
on
1 Post
I thought 85-86 "S" shortblocks were basically interchangeable with the 87-91 S4 shortblocks...definitely different pistons, but still 5.0 litre engine, and allegedly when used in conjunction with S4 cylinder heads...bump compression to close to 11 to 1. Maybe more to it than meets the eye, but I assume the 5.0 85-86 block is what he was referring to using with the rest of his engine components...not the 4.7 block.
03-22-2006, 03:03 PM
#4
Addict
Rennlist Member
Rennlist Member
He's talking about an 85-86 block. He keeps threatening to come over and steal mine. I'm trying to figure out a way to lock my engine into my engine bay. I saw how quick he took his cracked block out and it was scarey. This guy is GOOD!
03-22-2006, 03:13 PM
#5
Drifting
ah ok, that makes sense! i was picturing a torturous conversion using one of the earlier engines... is there that much difference between prices for used short blocks S3 vs S4?
03-22-2006, 04:05 PM
#6
Three Wheelin'
Join Date: Nov 2003
Location: Los Angeles, CA
Posts: 1,577
Likes: 0
Received 0 Likes
on
0 Posts
If you're thinking complete motor swap (85/86 heads too), I think the 85/86 heads lack the cam sensor, BUT I believe the car should run without it (with reduced timing). I don't know if the knock sensors will do anything without the cam sensor.
If you're thinking about putting S4 heads on an 85/86, won't that change the compression significantly?
If you're thinking about putting S4 heads on an 85/86, won't that change the compression significantly?
Trending Topics
03-22-2006, 04:12 PM
#8
Addict
Rennlist Member
Rennlist Member
Thread Starter
Join Date: Dec 2003
Location: Houma, LA.
Posts: 546
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Sterling
the 85-86 block will work. There are threaded bosses for the knock sensors. You will have to grind off 2 thread bosses in the V so that the S4 intake will fit.
You will also need to use the 85-86 starter bracket as the 90 model starter bracket will not bolt up.
Otherwise there are no other phisical limitations that I can remember. I used an 86 block in my 90 model.
I do have an 85-86 starter bracket in excellent condition should you need one.
You will also need to use the 85-86 starter bracket as the 90 model starter bracket will not bolt up.
Otherwise there are no other phisical limitations that I can remember. I used an 86 block in my 90 model.
I do have an 85-86 starter bracket in excellent condition should you need one.
So you've done this before? Any draw back?
03-22-2006, 06:10 PM
#9
Road Warrior
Rennlist Member
Rennlist Member
I used my 85 block w/late model heads, ECU's, harnesses, etc... ditto what sterling said. unless you are planning to punch it out or can just get one super cheap - I wouldn't bother.