GMPP 350 HO crate motor advice ?

[Wyomingboy]

Guys, I am wanting to put a crate motor in my 90 blazer with TBI. I have found a place in California called TurboCity, that modifies TBI systems for higher flow and burns the chips for the computer to work with any of these higher output engines originally built for carbs.

I am thinking of either the GM Performance Parts HT383, which has a great power spread and 435ft-lb of torque or the less expensive 350 HO, which has 330HP & @ 370ft-lb of torque. Both of these motors will need TBI work from what I have been able to find out.

I mainly want a motor that will pull overdrive with stock gearing & tires up the long grades we have in the mountain states, without excessive(or any?) shifting.

So does anyone have any experience using either of these two motors in your Chevy truck?

Thanks & regards,

Wyomingboy

 

[dyeager535]

I can't help with those specific engines, but have you checked out tbichips.com?

Brian over there has apparently been working with an engine builder to put together "packages" that are essentially turn-key. The TBI is matched to the engine perfectly, or I'm assuming as perfectly as can be without individual combo tuning time.

He's got a good rep, so I'd not be too worried about being satisfied from him. Not saying turbocity is no good, I just know that Brian has a good rep.

 

[Wyomingboy]

in fact I did check out his site last night after I posted this thread and I liked what I saw!
So I think I will be getting a crate from the people he recommends. So thanks for confirming that !

 

[dyeager535]

It makes sense I think, since he knows how the engine is going to perform to a great degree, he can simply burn a copy of a chip that is known to work well with that engine.

 

[Mike D]

Find out the torque curve of both engines. overdrive reduces the engine RPM, The engine that generates the greater torque at the lower RPM ( around 2000 )is the best choice. Also bear in mind no engine will pull a vehicle if the overall ratio is less than 2.55:1 . If you put larger tires on your truck eg. from 30" to 33" you automatically reduced the effective rear axle ratio by 10%. That means a 4.11 axle became a 3.70 .Now if your OD transmission is 0.75:1 Your true ratio ( what the engine sees ) is 2.78 . The bottom line is to calculate the engine RPM at the highway speed you want and pick an engine that is generating at least 50% of its maximum torque. You will be happy and so will your engine!

 

[noJeepshere]

I mainly want a motor that will pull overdrive with stock gearing & tires up the long grades we have in the mountain states, without excessive(or any?) shifting.

I wouldn't want to try a chug up a grade towing anything in OD in anything (gas or diesel) OD is not a very strong gear to begin with and having the extra weight of a trailer means failure sometime sooner then later. pull it into D and save your engine and tranny.

the 383 will make more torque then the 350 because of its longer stroke, and at a lower range, I think that would be your best bet for towing.