3500 Top End Swap

It has been about a month now, but I have swapped the 3500 top end to my 01 Grand Am GT. I have been playing with the tune when I have time and I am getting it close. The car seems to pulls alot harder even with a little KR.

There were a few obsticles and changes, but noting too major.

Some of the things I had to do:

1.) The 3500 gasket set (which at this time is only available through GM) uses a gasket now to seal where the LIM and block meet. The 3400 block is not drilled for these new gaskets, so if you want to use them you must drill the block or use a large pile of RTV. I chose to drill the block and had no problems. You will need to drill 4 holes less than 1/4" deep, however make sure to have a vac running and grease the drill bit

The Gasket:


Drilling the Block:


Gasket in Place:


2.) The Coolant Temp Sensor on the 3500 is no located in the side of the rear cylinder head as opposed to on the water neck. This called for a 6" extention to the wiring harness.

3.) The Cam Position Sensor harness had to be extended 6" due to the height difference of the 3500 manifolds.

4.) The Map sensor connector had to be replaced to be switched to the new style connector used on the 3500. The correct pig tail can be found on 98+ Chevy Cavaliers.



5.) The neck on the 3500 Plenum had to be ground significantly, due to the 3400's fuel pressure regulator. An epoxy putty was used to fill spots where the metal became too thin on the 3500 Plenum neck.


My mod list is as follows:

3500 Heads


3500 LIM

3500 Plenum

65mm TB and Adapter from http://60degreev6.com/store/


TOG Headers

Borla Catback

(I am currently working on tuning via DHP Powrtuner)

I will be getting dyno and track results as soon as I can get everything tuned as I currently have about 10 degrees of KR.


Here are more pics of the swap.

awesome to hear you got it all back together. make sure to come back with those slips!!

[brim]

very nice man

[BlackJack]

looking good man, nice job!

Thanks for the comments, I am getting there with the tuning and it seems to get better and better every time I play with the tune.

The only down side is that my compression dropped from 9.6:1 to 9.2:1 after I milled them .020" If they were not milled I would have a CR of 9.0:1 which would be perfect for those running forced induction.

The 3500 heads also flow as well as ported 3400 heads.

[Redog]

Sweet

[BlackJack]

ah, I dont know. I think you'd be alright for forced induction, just wont be able to run as much timing. I intentionally am dropping my compression to 8.9:1 using .070 gaskets on stock deck height. Get a little more timing into it that way

[SilverBullet256]

so overall performance wise, do you see a noticeable gain without the headers

Originally posted by SilverBullet256@Apr 12 2006, 01:40 AM
so overall performance wise, do you see a noticeable gain without the headers

Quoted post

I put everything on at the same time, so I am not sure how it would be without headers. However in theory the heads and manifolds flow alot better, so it should give a decent gain without headers.

[-Alero-]

yeah i was thinking about doing this swap a long time ago, i knew there would be some hefty work involved but didnt think there was that much.

looking back im kinda glad i didnt do it cause it seem like a pain in the ass.

also the 3500 plenum kinda made me turn my head, since i enjoyed the look of the 3400 UIM.

also did you use the "Updated throttle system" for the TB?

and i also just noticed you have all this work done but dont even have an intake? what gives?

looks like he gotta new bigger TB instead

Originally posted by -Alero-@Apr 12 2006, 06:04 PM
yeah i was thinking about doing this swap a long time ago, i knew there would be some hefty work involved but didnt think there was that much.

looking back im kinda glad i didnt do it cause it seem like a pain in the ass.

also the 3500 plenum kinda made me turn my head, since i enjoyed the look of the 3400 UIM.

also did you use the "Updated throttle system" for the TB?

and i also just noticed you have all this work done but dont even have an intake? what gives?

Quoted post

The swap really wasn't any harder than swapping to ported 3400 heads.

I didn't have to drill the block I could have used RTV like they do on the 3400 manifold, but I chose to take advantage of the new gaskets that were provided with the 3500 gasket set.

The only thing I would consider major is extending wires and grinding the neck on the plenum, and cutting / welding the TOG down pipe.

I completed the swap in 3 days by myself and this was my first time doing any engine work of this kind. Total I had about 30 -35 hours in it and if I were to do it again I could cut a few hours knowing what all is involved. It really wasn't as hard as it seems and i had alot of fun doing it.

As for the comment about the intake I don't buy into the whole intake hype. Stock AC Delco filters have been proven to filter alot better than K&N filters, my AIT temps are low with the stock air box (during tonights scan my IAT averaged 24*C which is about 75* F) I don't think I am having any problem getting air into the engine.

No I did not use the electronic TB that is found on the 3500.
The TB that I am using is a 65mm TB from http://60degreev6.com/store/index.php?act=...9c476f7f82d8721

The TB's are designed to bolt up to the 3400 manifolds and they offer an adapter plate to fit the 3500 manifold. So any of the 3400 guys can use them as well. They are offered in two sizes 62mm and 65mm and they are a very quality piece for the price.

[BlackJack]

I agree, that TCE 65mm TB is sweet! I went a little less expensive route however and found that with a little adapting, the 70mm TB from a 4.3 vortec mounts up just fine. I'm using a modified 3500 UIM on my setup, and it's nice that the stock neck starts at 65mm, and with porting, will allow me to make use of that 70mm. Takes a little modding to make it work however...cables, etc. Overall, your project looks good, and I'm glad to hear that it pulls much better now.

I figured up my total costs to be under $2400 with the following items:

Tog Headers
Borla Catback
3500 top end with LS6 springs, new valve seals, valve job, cleaned up casting marks and decked .020
65mm TB
DHP tuner
Gaskets and misc install parts

I am hoping to run a 14.7 or lower 1/4th mile, but only time will tell.

[SilverBullet256]

the only thing you should do now is get your cam re-ground or get a new one and you'll easily make low 14's with those mods

[-Alero-]

+1 on the cam.

i want one so bad, but i'll end having to get cyl heads and a cam to take car of it all at once >_>