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Full Version: ak_petey 's blazer upgrade - stage 1
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I was hoping to gather some ideas for my 87blazer.

I would like to spin my tires FASTER through the mud.
Ive contemplated an engine build, doubler kit, or engine modifications but I cannot do them all due to not being mr money bags. So my deal is I want as much wheel spin as possible/effective. I can only choose one option at a time. Ideas?

I currently am running a stock 350 tbi, th 400 tranny, np205 t case, 5:13 gears locked f/r and 39x18 boggers.
A doubler will lower your gears, which will increase wheel spin when a lot of torque is needed to spin them, but not so much for overall speed (speed = wheel spin.) Lowering your gears takes away the top end, so you can turn the wheels slower while still in your higher torque range @ higher rpm's.

I think in this case you 5.13's are limiting you - Skitzo has 4.56's and my blazer has 4.88's. A lot of folks simply run the 4.10's and higher hp engines - you have the power to turn big tires with horsepower and 4.10's but don't reduce your overall tire speed/spin with too low of gears.

So at this point, doubler = no

New gears that are higher... probably not.

so I'd say build your engine for higher hp. That may be a bit tricky though as you'd also have to "tune" your computer, but I'm sure you could find some-way/someone to do that as well.
first thing I would like to do is run a pressure test. I dont have the tools to do this or know how to do it. I have heard its pretty easy from folks.

I would like to skip the "tuning" and go for the better engine build. However, I would like to keep it fuel injected if possible. Any ideas on this one kevin?
i think ill swap back to my 4.10 thirds next time i have plenty of power to turn the tires but i have no wheel speed with the 4.88 .. .. that and a 150 shot of funny gas wouldnt hurt ..lol
ak_petey Wrote:first thing I would like to do is run a pressure test. I dont have the tools to do this or know how to do it. I have heard its pretty easy from folks.


Are you meaning a compression test? I have the adapter/gauge to do this.

ak_petey Wrote:I would like to skip the "tuning" and go for the better engine build. However, I would like to keep it fuel injected if possible. Any ideas on this one kevin?

"Skip tuning and go for a better engine build" ummm. I think you misunderstood my post.

Tuning is for the computer.

The computer is tuned to the standard performance of the stock engine.

If you rebuild the engine for more horsepower (which is what I was suggesting) then the computer thinks something is wrong with your stock engine... thus WHEN you rebuild the engine for more hp, you will then need to tune the computer to understand the new things it is seeing from your now non-stock engine.

In other words, your stock computer will not understand your built engine. So your engine build and computer need to match.

Does that make sense?
makes sense. Smile
ChevyKev Wrote:Are you meaning a compression test? I have the adapter/gauge to do this.



"Skip tuning and go for a better engine build" ummm. I think you misunderstood my post.

Tuning is for the computer.

The computer is tuned to the standard performance of the stock engine.

If you rebuild the engine for more horsepower (which is what I was suggesting) then the computer thinks something is wrong with your stock engine... thus WHEN you rebuild the engine for more hp, you will then need to tune the computer to understand the new things it is seeing from your now non-stock engine.

In other words, your stock computer will not understand your built engine. So your engine build and computer need to match.

Does that make sense?

Wow Kev. You just made the best argument for Carb vs. EFI:lol:
genius he is!
78calico Wrote:Wow Kev. You just made the best argument for Carb vs. EFI:lol:

EXACTLY!!!