Advice on a Craigslist ad + Tbi mods

[midnitewarya]

My '91 K5 spun a rod bearing. It marred the crank and ruined the cap. Gonna be pricey to redo the block.

That said, I bumped into a Craigslist ad. This gentleman has an 89 block that he honed and ringed and redid the top end on. He claims to be getting 400+ hp, after the ecm tune of course.

Here's the ad...
http://sandiego.craigslist.org/nsd/pts/4181880355.html

I've been speaking with him, it looks like he knows a good deal about motors and he has certainly taken his time building a nice motor. Some of the stats on it that he provided : Summit top end kit. Hydraulic cam 288/289, aluminum heads 62cc chamber, 170/70 intake exhaust. He says the kit recommend a 600 cfm carb, so he bored his Tbi.

All the accessories are new. New nos wire harness with cruise, rebuilt 700r4. All for $2000. What do you guys think?

I'm thinking that flat tappet cam is gonna have a hard time with those heads, assuming I can get a good tune out of it. But the wire harness and accessories kinda make this a deal. I still have my oem top end, I could always reuse that...

Thanks in advance yall!

 

[rebelgregory]

Motor looks good, but according to everything I've read, TBI won't support that kind of power.

 

[midnitewarya]

Thats exactly what I'm thinking. I don't think that motor will ever see those numbers, but I'm wondering if it's even possible to tune it. I don't think he did anything with the fuel pump or fuel pressure. I'd be happy if I could get a reliable tune out of it.

 

[F-ingrob]

ive read the same thing TBI doesnt do well over 5000 RPMs

 

[dhcomp]

Craigslist motors, or privately built motors, are only as good as the guy who built them.

If you don't know the guy, its not worth 2k. No matter what he can "prove" he did.

You can get a GM TBI crate motor delivered to your door step for $1995.

On top of that, i have my doubts about the TBI tuning. I'd pass on it. I think its too good to be true.

 

[Blue85]

He gives estimated power, but then mentions that the ECM needs a tune, meaning the engine has never actually made this power. It's probably a tweaked Desktop Dyno number or something. Still, you have the option to look into other FI setups. A lot of guys get the big block TBI throttle - maybe you can compare the capabilities of that setup with this modified one. It doesn't say what kind of injectors are in there, so that's important.

Did he tell you he was throwing in a trans? I don't see that in the ad. Anyway, you would end up with extra accessories and maybe an extra trans. You should estimate what those could sell for locally and the deal might become really good. Can you hear it run?

 

[Russell]

TBI won't run properly with that cam profile without a LOT of work on the tune. I wouldn't go for it if you want to keep your EFI.

It would be cheaper to buy a Chevy 6.0L and retrofit it. Make 300hp bone stock and have all the advantages of modern fuel injection.

 

[ccarley]

Estimated horsepower numbers, LOL.

 

[Blue85]

I estimate that my SBC makes between 5-600HP.






That is: the number is greater than 5HP and less than 600HP.

 

[midnitewarya]

Thanks for the input guys. I passed this one up. Good luck to the dude that gets that motor.