gm crate engines

[iceman]

Here's my crate engine story from GM.

 

My 454HO burned oil from day 1 and always ran hot. I had about 2K miles on it when I had a local engine builder help me do some diagnosis.

 

On the leak down test, 6 cylinders were less than 4%. #8 cyclinder was down 65% due to a bent exhaust valve and #1 was down 15% due to stacked rings.

 

I took the car to a GM dealer to honor the warranty ... he told me to pound sand since they didn't install the engine.

 

Since things had to be replaced anyway, I decided to rebuild the engine I had rather than fighting GM. I tried to drain the coolant but nothing would come out of the bottom plugs. When I popped the intake and heads, all of the coolant came up through the top. Why ... because the core sand was still left in the coolant passages so little coolant was running through the engine. This was also evident on the bearings because they were all scored from grains of sand. Fortunately the crank wasn't damaged (probably because it was steel). Then we started taking measurements on the block. There was about .060" rise in the driver's side deck, putting #7 piston down .065" when the piston was at TDC.

 

So with a fresh machining and the assistance of a few really good gear heads with lots of engine building experience, I was able to salvage the block and crank but improve everything else to have the motor that I should have gotten from GM in the first place.

 

For anyone choosing to go the crate engine route, just be sure to look at the fine print in the warranty to make sure that you are covered if you do any of the installation.

[7tonemonte]

Thats a scary story Stan... I guess its all just luck of the draw no matter what route you take. I thought the warranty stated it was ok to do the install yourself?

[gprimm]

That's why I like an experienced builder who looks at every part. Crate engines are just that; mass produced volume. I learned my lesson and here's yet another story.

[Mike Brichta]

I think it really comes down to the dealer who sold the engine. When I had my zz454 problems they never even asked if I installed it myself or not. I sent them the paperwork with some pics of the car and engine and they said they would take care of it. The entire engine was rebuilt with free parts and labor which is what the warranty is supposed to do. No complaints as far as the warranty was concerned.

 

I would have been much happier if I never had the problem but now I feel better about the engine because I was able to meet and talk to the GM engine guy that rebuild the engine and he was more than happy to get his hands on a zz454 to play with. I'm sure he took his time on the rebuild because he knows I would be back if I had any problems.

 

It was a pain but cost me nothing other than my time to get it resolved.

 

Mike

[iceman]

This was early in the GM Performance parts days so things may have changed in how they do the warranties. It still comes down to buyer beware.

 

I will say that my engine was built the week between Christmas and New Year so that might have something to do with the problems!

[Clever Idiot]

-has anyone seen a twin turbo monte?

 

Saw one at a Super Chevy Show in Gainesville years back. It was a 454 twin turbo, too. Absolutely beautiful. And that huge engine bay was jammed with piping, even with a big cowl for the intake. Massive, delicious 4" or larger piping. I still have some pics around here somewhere.

 

And maaaaaaan... You guys are really making me think about doing a big-block instead of building up the 350. I should stay away from here! I always come away with new ways to spend money I don't have yet!

[Jared Richey]

Not to mention the high cost of a crate engine. I mean a ZZ572 is awesome, don't get me wrong! But $12-13k for an engine with only 620 HP???

 

My 462 has close to that with 1/4 of the $$ invested and thats with a Hydraulic Flat Tapped camshaft, from what I understand I have a lot left on the table if I convert to a roller one day.

 

 

[7tonemonte]

While the higher big block ones seem to be pricey, I dont think for the money of a new small block you can beat what you get for a complete turn-key motor really. I dont even think the cost of the 454 ones are all that bad, I guess its all in personal preference, the warranty is a nice thing, if you can get it handled if there is a problem. Not sure which way Ill go when the time comes, but I was leaning towards crate motor, numbers matching is less than meaningless on my car

[MGD72Monte]

Seem like no one is touching on the do it yourself option whenever possible I find brings about more satisfaction and a better understanding even if it is not the cheapest route. To me it is a big part of the hobby. Not everybody's cup of tea I know, but something to think about before making a final decision.

[Clever Idiot]

Well, that's what I've been planning to do with my 350. Get it tanked and build it up myself. I'd go the same route with a big block.

 

Since I'm not planning on building for maximum horsepower, I don't think my tolerances and such are going to be so tight that I end up building a bomb. I'm a little concerned with getting in over my head, but it wouldn't be the first time. I'm pretty confident that between my skills and this forum I'd get it done right.

 

I'm just thinking big block for the easy low-end torque and goosebump-inducing sound.

[Heckeng]

I agree with what some have said above--it depends on what you are looking to do.

 

I have had a GM crate 454HO for 14 years, and just bought a new 502 short block and added my own heads, cam, intake etc.

 

I considered having Mike Lewis, or a couple other builders put together an engine for me and I have NO doubt that it would have kicked @#$% but I didn't have a block or crank that I wanted to use to start out. If I bought a forged crank and a new block, I would have gone overboard and bought a Dart or similar block and my cost would have gone up pretty quickly. Getting the GM crate gets you a good combination of quality parts with performance for what I would consider a reasonable cost. The new 502 blocks are supposed to be even stronger and more reinforced than the old ones which were already great so I liked that option. Their cranks and heads are all forged on the high performance stuff to my knowledge and if you get their heads, they are Edelbrock which have a good solid track record as well.

 

The complaints you hear are oil burning because of the low tension oil rings, and some people claim that on the 454 Gen VI blocks there is some ring seal issues that can be taken care of by honing the cylinders with a torque plate installed.

 

I am sure there are people who will have horror stories about any crate motor you can find out there, but there are also horror stories to go along with people having their engines custom built, so pick your poison!

 

Also, that sounds like your last motor was a beast, put up some engine specs like cam and heads! Love that stuff :-)

[Steve G]

I have had 3 GM crate engines..... good for the price... the advertised Horsepower is best case and not likely.. somewhat sedated performance compared to what they advertise.. but they do run smooth... Good credit card purchase.