: '91 4.9 installed in a '85 Seville-can it be done and any thoughts

Duane Hayes
02-24-13, 01:23 PM
Without me going through all the posts here, wondering if the 4.9 is a direct bolt in to replace a 4.1 in a 1985. I realize that the computer and engine controls are probably somewhat different. But I would just use all the 4100 controls and computer, and perhaps the computer wouldn't know the difference in the increased displacement. I didn't see a search option here on the site to search this question, maybe I missed this. Duane

02-26-13, 02:23 AM
This thread will give you all the info you will need to use a 4.9 block in the 4.1 application.


03-01-13, 03:06 PM
On a 85 Seville the engine faces forward and the trans sits beside it unlike a newer front wheel drive engine where the engine is sideways. A 4.9 will not bolt up to your transmission number one and the engine block casting wont allow a proper engine driven fan. a 85 DeVille can be adapted to a 4.9 as you've seen in the above posters link.

Duane Hayes
03-11-13, 11:53 AM
Thanks so much, that's information I didn't know about, appreciate your help for sure! Duane

03-16-13, 10:47 PM
Make the transmission fit....Use electric cooling fan..or two small ones...