Which block is best for building up

poobala · poobala's Garage

I am looking at purchasing a 2.7 to build as time and money allow is there a specific block casting #'s that are better for this project ?

82SC · 09-18-2002, 06:34 PM

well I think the answer would be a 7R case...I am sure other will chime in...

on a related note...I plan to build a 2.7RS clone as well...

I think a 2.2-2.4 case can be used as well?
the spigots would have to be bored out...

is it more cost effective to buy a 7R case or a 2.2/2.4 engine and mod it...

MJ

Fishcop · Fishcop's Garage

Bump

I'm interested too

Bobboloo · Bobboloo's Garage

If any of the following is redundant please excuse:

The 7R was the best design for the mag cases but most out there need a bit of work before they should be used in a rebuild. That's because most were used in 2.7L CIS engines with thermal reactors. So these cases got stressed by excessive heat from the combo of leaner fuel mixture and thermal reactors.
They were also stressed by the, well documented, miss-match of expansion rates between iron head studs and alloy cylinders.

The exceptions for the 7R case however is the ones used for late 73' T motors. These motors didn't have thermal reactors or the 90mm alloy cylinders which makes them the most desirable of the 7R cases. They do have to have the spigots bored for the larger cylinders however in a 2.7 application.

The 74' 2.7 motors also didn't have thermal reactors either but had the 90mm alloy cylinders. Quite often they were Alusil as opposed to Nickasil but I'm unaware of any differences in the expansion rates between the two. Although Nickasil was c ast in a centrifuge which made them denser so they probably expand a little slower than the Alusil.

Another good possibility is the 5R cases for the 72'-73' MFI T motors.
These cases may not have as much internal reinforcement as the 7R but they were used in a motor that had iron cylinders that matched the thermal expansion rate of the head studs. They also didn't have thermal reactors and they ran cooler because of the low 7.5:1 compression and the richer (than CIS) MFI fuel system. These are similar to the 7R in the thickness of the spigot land for the cylinders.

One more consideration is a late 77" CIS motor because they used a 7R case with Dilivar studs on the top and bottom row. So atleast they are likely to be in good shape as far as the spigot base is concerned. The y did however use thermal reactors so once again the case is subject to distortion from excessive heat.

My first choice would probably be a late 73'T 7R case. Second choice would be a toss up between a 72'-73'T 5R and a late 77' 7R.

At any rate. They all should be checked for the condition of the crank bore. (Ovalness and alignment) As well as the squareness of the edges of the case halves and spigot bases.

I have (2) T MFI motors with the 5R case. Both when dissassembled had very even wear of the main bearings, suggesting that oval wear has not been occuring in the crank bore for what it's worth.

This is all I know, hopefully the voice of experience will weigh in if JohnWalker responds.

Bobby

GeorgeK · 09-19-2002, 01:28 AM

I'd say the Carrera 3.0/ turbo 3.0 block and crank.
The last of the lightweights, and the first in alloy.
GeorgeK

poobala · poobala's Garage

Thanks for the info , I have a 2.2 I believe, 901 106 101 5R is this a potential build up motor ?

jstgermaine · jstgermaine's Garage

In my best F2P imitation, I have a 2.7 in a '77, if anyone wants it, it's yours if you take it out!

82SC · 09-19-2002, 07:59 AM

well if you are serious let me know...I am looking to buy a 2.7L

MJ

jstgermaine · jstgermaine's Garage

A serious as a heart attack!!! You want it...come and get it!

For those of you from far off places, my neighbor works for ADL and assures me he can get you a great deal on shipping this thing anywhere in the continental U.S.

NapTownSpeedy · 09-19-2002, 08:16 AM

Jerry,
Just sent you an email. Let me know.

724doorE · 09-19-2002, 08:16 AM

Jerry,

check your email.

I'm standing in your driveway with a floor jack and a tool box looking for a white P-car to dismember!

Seriously, let me know ...

Might be able to do it this weekend.

82SC · 09-19-2002, 09:03 AM

broken?

well I am in LA...too bad it would make a nice addition to the free targa....

if you'd like to contribute to the experiment - how cheap can you restore a car...let me know...I'd pay shipping and labor

I've already gotten some donations and some really really really cheap parts from members...

MJ

jstgermaine · jstgermaine's Garage

724doorE & NapTownSpeedy,

Sent you both an email outlining the particulars.

NapTown your email cam back undeliverable, if you have another let me know.

The jist of the outcome is this...while NapTown's post shows here first, 724doorE sent me an email 3 minutes prior to the postings and earlier than NapTown, thus giving first right of refusal to 724doorE.

However if 724doorE can't make it....

Check your emails and see if the parameters work for you. Let me know!

NapTownSpeedy · 09-20-2002, 05:38 AM

if 724doorE doesn't let you know today, I can be there tomorrow with tools and jacks.
I'll send you a PM, I've been having email havoc lately (change in companies).
Just let me know, I can adjust to your schedule (it is your engine afterall!)
Thanks.

jstgermaine · jstgermaine's Garage

724doorE, will be in my garage the weekend of Oct. 12 to remove the 2.7

We'll take lots of pics....