3400 hp ratings

[laveryt]

Im getting ready to purchase a 3400 to drop into my 89 Z-24 and I have been noticing that in different years and models the hp changes.

Does anyone know what the differnce is in the 185hp minivan motor and the 170hp Alero motor? What would cause the 15hp differnce in a motor that is essentially the same?

[Rhedalert]

I know at least the throttle body in the minivans are 56mm vs the 52mm in the N body....also doesnt the van have better exhaust manifolds?

[v6h.o.]

the 3400's do have better rear manifolds, and all 3400's have 56mm throttle bodies, 3100's have the 52mm.

the difference is in GM's PCM programing, and the exh setup, intake setup of these engines that is the only difference between a 175 and 185 HP rating 3400,

the cams, heads, block, intakes, exhmanifolds, t/body, are all the same between them.

[ikessky]

Hmmm.... so GM has the ability to tune these engines better, they just choose not to........

[geoffinbc]

Extra tuning kills gas milage.

[ikessky]

Going up by 10-15HP doesn't kill gas mileage that much. I would say that a bigger factor is the weight difference between minivans and Alero's or other 3x00 powered cars.

[laveryt]

So...If I am hearing this correctly, it wont matter what 3400 motor I put in the Z-24, because I will be using the 2.8 ECM with a reprogram anyways.

And that reprogram will determine the hp, not the motor itself.

Is that a correct assessment of the thread so far?

[Rhedalert]

the 3400's do have better rear manifolds, and all 3400's have 56mm throttle bodies, 3100's have the 52mm.

.

Even the N-bodies? My friend has a '99 Alero and it looked like a 52mm. I had a 56mm in my trunk and I could have sworn I saw the size difference.

[razorz26]

Are the hp ratings measured at the wheels? If so, the hp difference could be a result of the different transmissions, since minivans use a 4T65-E with a final drive ratio of 3.29 and the Alero and Grand Am use a 4T45-E with a 3.05 fdr

[robby1870]

They are measured at the flywheel

[ikessky]

Wow, that's not much to the wheels then.........

[Blackrider]

Are the hp ratings measured at the wheels? If so, the hp difference could be a result of the different transmissions, since minivans use a 4T65-E with a final drive ratio of 3.29 and the Alero and Grand Am use a 4T45-E with a 3.05 fdr

I'm not to sure about the vans final drive but I KNOW the Grand am GT has the 4T45-E witch has a Final drive of 3.29 The Alero and GASE's have a final drive of 3.05

[ikessky]

Unless the Alero and SE you are talking about has the 4 cylinder engine, they should all have the 4T45E.....

[Cliff8928]

the 3400's do have better rear manifolds, and all 3400's have 56mm throttle bodies, 3100's have the 52mm.

.

Even the N-bodies? My friend has a '99 Alero and it looked like a 52mm. I had a 56mm in my trunk and I could have sworn I saw the size difference.

My engine came from a 99 Alero and it had a 56mm on it...

Cliff Scott
89 BerettaGT
89 Volvo740

[Blackrider]

Unless the Alero and SE you are talking about has the 4 cylinder engine, they should all have the 4T45E.....

The Alero and GASE have the 4T45 The GAGT is the only Nbody with the 4T45-E with the 3.29FD