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HT crate motor requires 92 octane?

dremu

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Was looking at the GM crate motor, specifcally the HT502 <grunt grunt> ... until I read it runs on 92 octane. :doah: It's bad enough I gotta pay for the motor, but now my gas bill goes up?

Is there a point to retarding an engine like that to run on lower octane, or is it like a function of the compression ratio and I should just be looking at a more normal motor that'll run on the cheap stuff?

-- A
 
it's due to the compression ratio, cylinder heads, and the camshaft in the motor. Retarding the timing probably won't help, although it is a solution, you will be down on power compared to premium fuel.
 
xpndbl3 said:
it's due to the compression ratio, cylinder heads, and the camshaft in the motor. Retarding the timing probably won't help, although it is a solution, you will be down on power compared to premium fuel.

Yeah, and then what's the point of a high-zoot motor if it's detuned -- be kinda dumb on my part.

Stock motor is looking better and better :)

-- A
 
Last winter i looked at the same idea. I wanted a 502 so bad. But after weighing out all the cost i ended up putting in the 330 hp crate SBC. I've always had BBC but i think i made the right choice. It was tested on 87 octane, i run it on 87 octane, and i keep the bills down. I will say the 8 mpg i get doesn't really back my story very well but im happy with the SBC.
 
makovai said:
Last winter i looked at the same idea. I wanted a 502 so bad. But after weighing out all the cost i ended up putting in the 330 hp crate SBC. I've always had BBC but i think i made the right choice. It was tested on 87 octane, i run it on 87 octane, and i keep the bills down. I will say the 8 mpg i get doesn't really back my story very well but im happy with the SBC.

Well, the truck has a 454 now ... it's a crewcab and is my tow rig, so an SBC ain't gonna cut it. Don't care about HP so much as torque... so that HT502 with like 500ft-lbs was just sexxxy... but I think rebuilding the one I have, maybe a bit of a cam upgrade or something, will be a nice balance.

Hell, at least it'll spin =))

-- A
 
rebuilding the factory 454 with better cam and some head porting/swapping and a different intake will make a world of difference along with some nice long tube headers, h-pipe and duals.
 
Ahhh...the joys of shopping for engines, when you actually need one! Have fun and enjoy the ride.

Did you teardown your current one. You sure it's rebuildable, like not a cracked block or something bad like that.
 
73k5blazer said:
Ahhh...the joys of shopping for engines, when you actually need one! Have fun and enjoy the ride.

Did you teardown your current one. You sure it's rebuildable, like not a cracked block or something bad like that.

Haven't touched it yet, as I gotta bring the truck in from the street into the yard which means I gotta clean the yard up to move the two K5's around which means I gotta clean the garage up which means ... :haha:

I'm hoping this week I'll get the truck pulled in off the street so I can start to tear her down and pull the motor.

Yeah, I'm a bit afraid of what I'll find :eek1: :rolleyes:

-- A
 
dremu said:
Well, the truck has a 454 now ... it's a crewcab and is my tow rig, so an SBC ain't gonna cut it. Don't care about HP so much as torque... so that HT502 with like 500ft-lbs was just sexxxy... but I think rebuilding the one I have, maybe a bit of a cam upgrade or something, will be a nice balance.

Hell, at least it'll spin =))

-- A

you make a valid point. I just hope you have a big wallet. The last BBC i did ended up costing me $12k but it was pretty as well as powerfull. 627HP and 703 torque. Dont get me wrong, a BBC sounds good on the road, in a story, and everywhere you go, but it cost 3x what a SBC does. Thats my only point.

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