Any way to tell which crate motor I have?

[COCHEV]

My 82 pickup had a gm crate installed by a previous owner (2 owners back) so I got no paper work on it. So I'm not sure if I have the 260 hp or the 290. Did some diggin on the interweb and found that both motors use the same block, so the casting number there would be the same either way.

From the way it drives and from what I've read about the 2 motors I'd say I have the 290 hp version with the 220/220 cam in it. Its seems to lack low end and likes a decent amount of advance to run well. However, previous owner also put a performer RPM and edlepuke 600 on it wich seems a weird combo as well.

Anywho, any other way to figure it out short of pulling the cam? I will be swaping the intake for a performer plus and Q-jet soon. I would also like a cam that complaments this...

 

[K85 Octane]

is there now stamping on it?
not the casting, but something the company stamped in for ID
I wonder if theres a way to measure the cam by rotating the crank with the valve covers off. Watching the rockers move
lol

 

[Hogback Fabrication]

Fuel and ignition will cause much more low end problems than a cam generally ever will.

If you don't know your air/fuel ratio or where the timing is and/or needs to be, there is no way to know if the cam is to blame for anything.

 

[COCHEV]

is there now stamping on it?
not the casting, but something the company stamped in for ID
I wonder if theres a way to measure the cam by rotating the crank with the valve covers off. Watching the rockers move
lol

it just has the gm crate 350 valve covers....

i'm sure if i had a micrometer i could check the lift that way. assuming there is a difference in lift between those two cams.

 

[COCHEV]

Fuel and ignition will cause much more low end problems than a cam generally ever will.

If you don't know your air/fuel ratio or where the timing is and/or needs to be, there is no way to know if the cam is to blame for anything.

very true. I don't know that i have a low end problem so much as maybe some miss matched components- big cam, small heads, big intake, small carb.

 

[Cornfield creations]

If the valve covers have the tag, then it is more than likely just the 260. Just a typical replacement engine. All the 290's I have seen have plain black centerbolt valve covers

 

[bronc3buster842001]

The crate motor I bought for my 96 didnt have the stickers on the valve covers. They came with it though.

 

[83k5blzrbob]

I bought a low mileage Crate 350 HO on craigslist and it had an aluminum tag stuck on the passenger side of the block that listed the following information:

Manufacture for General Motors in the USA
Part No. 12486041
Bore STD
Main Brg STD
Thrust Width STD
Rod Brg STD
Date 5/29/2001
Serial No. 15014063 S/C 7684

Regards,

 

[USSkoval]

The 260 and 290 horse motors both use the same valve covers. But did they use the same heads? I don't know.

Also, I'm not sure the 290 existed that long ago. So if the motor is fairly old, it's probably the 260. The 330 horse vortec headed motor USED to be a 300 horse model with standard heads. So, there would be no point in having a 290 and 300 horse model available at the same time. In short, I don't think the 290 was around before '00 or so.

 

[496truck]

Someone could have just as easily only swapped valve covers, and then gave the PO a line of BS saying it had a crate motor in it. And then the PO did his own upgrades. At this point, you have a 350. That is all.

If you have some running problems get them sorted out and go from there. If you are trying to determine cam size, I don't think there is any sure way to tell without pulling it and measuring it.

 

[COCHEV]

i'm not really having problems with it. it runs great and does not use oil. I beleive the motor is 3-4 years old. its certainly not a power house, but i do think its not running at its potential either.

I picked up a q-jet, and will be swapping the performer rpm for a spread bore performer plus or similar. not sure on the cam swap at the moment, i use the rig for work every day and can't really have it down long.