Help With mystery motor...

This is a v/8 chevy motor do not know the engine size for sure. The number on the block were T0611ctu the 11 may just be a divider between T06 and ctu?.It was removed from a 1974 1 ton truck.The odometer read 98,000 miles,I believe that is the actual miles.Four barrel carb. I was told it is a 400 cid.

This is what i was told about the motor...it could make a good rebuilder for my project, any info you could give me to shed light on this subject is greatly appreciated...

check to see if it has 3 freeze plugs per side if it does then its a 400 there is also something about the balance its either in the balancer or the fly wheel i think if its externally balanced its a 400 someone correct me if im wrong

T 06 11 C TU

T = Tonawanda, NY
06 = Month
11 = Day of Month
C = Vehicle Type (in this Case... "CAR")
TU = Engine ID Code

So its definitely not a "Truck" block.

According to two sources I checked... CTU was used for 1970 350 LT-1 "Corvette". (H.E.I., spec high perf, m/t LT1 370HP to be specific.)

However.... (see next post) :|

Alright... sorry for getting you hopes up... :(

CTU was also used on 1975 400 cid 175hp 4bbl LT4 .

http://www.chevy-camaro.com/chevy-camaro-chevy-engine-suffix-codes.asp

good lookin out. Its a 400 SBC LT4...Heh obviously not the same LT series as current...?

Something i should invest in?

Let me know...

CTU shows up as a 1970 Corvette LT1 engine or a 1975 400. You might want to get the casting date off the block just to be sure, but if it was in a 1974 truck then it probably is the 400.

Originally posted by Jeff H
CTU shows up as a 1970 Corvette LT1 engine or a 1975 400. You might want to get the casting date off the block just to be sure, but if it was in a 1974 truck then it probably is the 400. However, "CTU" is not a truck block. So its definitely not the original motor. It could be a '75 replacement, but its worth checking the casting dates... just in case. ;)

if possible, measure the bore and the main journal size. also, 400's have steam holes between the cylinders and yes, they are externally balanced.:D

Balancer on a 400 will have a scalloped out section on the outer ring. Check the block casting #. It is on the back of the engine on the bell housing extension, behind the oil pressure fitting.

Then check the number at mortec.com. If it ends in 509, it's a 400, like the one in my 71.:) But there are more 400 casting #'s.

Originally posted by kacy
check to see if it has 3 freeze plugs per side if it does then its a 400 there is also something about the balance its either in the balancer or the fly wheel i think if its externally balanced its a 400 someone correct me if im wrong \




Not all 400 smallies have 3 freeze plugs per side. My 509 casting 400 has 2 per side with a provision for a 3rd.

Yes all 400's were externally balanced.

Just wanted to add that Information.

heres a few pics of the engine....

http://www.bgom.net/engine

check those pics, should help ya be sure...

wellm i didnt see a real good pic of the balancer and only 2 freeze plugs and the way that alternator mount is set up i would guess that its probably not a 400 theres still a chance it could be as everyone else said either measure the bore or check the other #s you didnt put on the bored

Woah! Are those not Corvette exhaust manifolds?

Ummm, definitely check the castings because that looks like it might be a LT1. :eek:

Originally posted by kacy
wellm i didnt see a real good pic of the balancer and only 2 freeze plugs and the way that alternator mount is set up i would guess that its probably not a 400 theres still a chance it could be as everyone else said either measure the bore or check the other #s you didnt put on the bored

I think you can just make out the cutout portion of the balancer, but it's blurry. Not all 400's had 3 freeze plugs. The two 509 casting 400's I have built had only two.

Well, since it has 2 bolt mains, I don't think it's a Corvette LT1. You can also see what looks like an EGR valve on the side of the intake so it's probably a 70's or 80's motor. Did you check for the block casting date yet?

That engine looks to me like a 400. The main bearing caps are what to look at. They are much beefier than the 2-bolt caps on a 350. The sides of the 400 caps go into the block at an angle, whereas the 350's caps are straight up and down. That block also has the desirable untapped 3rd freeze plug, which some 400's have.

If you want a fast street/strip car on a budget, a 400 is the way to go. They make huge torque. I run a 400 in my '77 Z/28, and even though I still haven't sorted out all the bugs yet - the trans upshifts at 4900 instead of 5900 RPM - I've gone in the 12.40's at almost 110 mph in the heat at 3800 lbs. This is with a cheap Crane Blazer hyd. flat-tappet cam and stamped-steel GM rocker arms, and mildy ported stock Vortec heads, on BFG drag radials. With more grinding on the transmission governor weights to get my shift points up to 5700-5900 RPM, and some fine tuning of the combo, I feel an 11.90 is possible.

All I can say for sure is, after having a 400, I would not go back to a 350. :)

Check under the suffix code - there's a partial vin. If the second number there is a 5, you have a 1975 400cid engine, from an A or B body vehicle. ake off the heads. If the water holes are missing from between the bores, it's a confirmation. There are 2 and 4 bolt mains, and some did have two freeze plugs. Go behind the engine on the driver's side and check the casting number.

It's a great engine, if the block hasn't been misused. Be careful with part swaps, though, as there are differences that make a lot of sb parts incompatible without machining.

That 175hp engine can easily be boosted over 400 with a little planning and relatively inexpensively.

my experience with 400s .. 2 freeze plugs = 2 bolt mains .. 3 freeze plugs = 4 bolt mains .. also 2 bolt mains = thicker cylinder walls ..