2.5 tech 4 engine mods, are there any????

[hungy82]

Hello once again people.
Maybe somebody here can lead me in the right direction. Is there a web-site or company that makes engine upgrades or performance parts for the cutlass 2.5 tech 4 inline 4 cylinder engine?????? Much much thanks if u can help..... I checked out mantapart.com, but they specialize in the quad4 and v-6 engines......thanks.

[Ragtop_Renegade]

Not much has been done with the 2.5 in the aftermarket world. Because of it's antique all cast iron, over head valve design, there isn't a lot of performance potential. The 2.5 was engineered to be cheap to mass produce, and appeal to those looking for good gas mileage rather then those wanting quick quarter miles.

The one thing you might want to check out is the super duty 4, a racing version of the 2.5L built by gm performance parts/Pontiac racing as a contender in the 4 cylinder racing world. most super duty parts fit production blocks. By the way, the 2.5 "Pontiac Iron Duke" was engineered and built by Pontiac division, though it did cross into Olds as well as Buick and Chevy.

[MrPbody]

Yup. GM Performance has a raft of parts for the 2.5. The SD is dominant in classes such as the Goodies' Dash series. Very popular in the midget crowd as well. We've seen as much as 310 HP from a normally aspirated version with injection. The aluminum head is a work of art!
The engine is so capable, it's not welcome in NOPI. Neither are the Quad-4s. Saturn is the only GM entry. At 1.9 lr., it's no wonder the bigger Hondas and Toyotas are a little quicker.

Jim

[MagicRat]

Also, consider using a marine block 2.9 liter engine.
It is externally the same as a 2.5, with 400 more cc and much stronger interrnals. They came with 140 hp stock, (but can easily produce more) and are designed for the stress of full-throttle operation all day long.

[Ragtop_Renegade]

I seem to recall reading somewhere the Mercruiser 2.9 had same-side head ports, versus the regular 2.5's cross flow with intake on one side, exhaust the other. I wonder what swapping a ported 'duke head onto a 2.9 would do......