Hi guys!

I have a 1998 C5 Vette with a six-speed and 107,000 miles. My timing chain broke and the pistons smashed the valves.

I'm looking at 2 replacement engines: a Pontiac GTO LS1 (350 HP) with an intake manifold but a GTO oil pan

and a 2003 Corvette motor with no intake manifold included, but it does have the Corvette oil pan.

The GTO motor is $250 cheaper than the vette motor and both are in the same shape.

I have a few questions.

Will my 1998 Vette oil pan fit onto the GTO motor (i.e. will the bolt patterns and metal match up)?

Will my 1998 Corvette intake manifold fit properly on the 2003 Corvette motor? Will there be gaps? I heard there might be a problem with the wiring for the knock sensor.

Which motor do you guys think I should buy?

Thanks!

Mike

 

get the vet. engine and swap the intake. will be much easier and less hassle to do the swap.

 

How much for the engines? You might be better off upgrading to a 402.

 

I highly doubt he can do a 402 build-up, when he is worried about a $250 difference in price between the 2 motors. To me he is looking at a budget build to get him back on the road. I could be wrong.


cobrataxx,

Welcome to the club. I have a broke piston currently also.

 

what year gto?

 

LS1 is 04.

 

Get the one with the least miles.
The GTO will fit perfectly. Just need to change oil pans and peripherals. One thing to note is it will have a newer block so the head bolts will have to be for that specific year. (equal length)

 

Get the lower milage motor, but I'd suggest the GTo motor as it has the superior LS6 intake which is much better than the intake you have on your car now. The pans should bolt right up.

 

I blew my motor as well but i only had 28K on the clock. I'm going with a fully forged 402 but if money was supper tight i would look on CF or z06vette.com and see if you can pick a used LS1 or LS6. I've seen them go for 3K or less with low milage. Just an idea. Good luck to you! I know what you're going threw, it sucks. My car is still down at the moment.

 

Thanks guys for your input!!

I talked to an engine rebuilder and he said that the GTO intake manifold was not the same as the Corvette intake manifold. He suggested going with the 2002/2003 Vette motor.


So that brings about a new question: Is the intake for 2001 and newer standard vettes (with LS1s), the same as for the 2001 and newer ZO6s?

(Because I'm thinking of tossing my 1998 LS1 intake and wondering if there are more than one GM intake manifolds made for 2001 and newer cars [i.e. a 2001+ LS1 and a 2001+ LS6 intake manifold--or are they both the same?])

 

I'm not aware of any differences in the 2004 intake. 2005 was the swap to the ls2. I think your rebuilder needs to check his info.

 

the intkae manifolds are the same

 

That's a crap shoot.... I've got an Feb '04 build GTO with the 16 long/ 4short setup.

 

Save your money and get LS7 , I am sure GM has part numbers for motor replacement..GM performance came out with a new catalog that has a few pages worth. Call SDPC ----> they could give you a good idea

 

No diffrence in intake fitment between the years. Get the GTO motor and bolt on your pan. Then you'll have a better LS-6 intake than the LS1 intake that's on your car.

 

id go gto too! Id rather do a pan swap and have a better intake,than a old one.

 

The block has to be a 2004 casting, remember the 04 GTOs came out in late 03. I'm just saying to check out casting numbers, in case he does head swap, he knows what he is up against.

 

whats the 2004 casting number vs the 03' and later blocks??

 

Just curious what the engine did when it blew up?
Doug

 

I was driving in third gear, when all of a sudden the revs went up to redline (as if the engine had no load). The timing chain broke, and I guess the crank was "free-revving". I didn't hear ANY noise, and coasted to the side of the road without power. Half the valves are now bent (they are not flush with the head when fully retracted). One of the pistons now has a perfect circular impression in it now