[BLACKFXGT]

I will be building a 3L block to be supercharged. I will be using 3L lower end with 2.5 heads. My question is what type of cams are good for this setup? Using 2.5 or 3L cams or get the 2.5 regrinded to SVT specs?

 

[PuckPuck]

Taurus/Escape 3L Oval Port Intake Cams...
Mazda 6 3L Exhaust Cams....

you will need to cut off a portion on the Mazda 6 exhaust cam for the left head, as the mazda 6 drives the water pump from the exhaust, while all others drive it from the intake cam....

This combination will give you the least amount of overlap, which is a goal in force induction applications

 

[JustinS]

3l bottom end with 2.5l heads is going to net you a compression ratio of 11:1, not a good idea if you want to boost. stick with the 3l heads and have them portmatched to the 2.5l intake manifolds or use 3l intake manifolds.

plus, the 3l heads are supposedly better for oil return purposes. i think anyways, someone correct me if i am wrong here...

 

[Rikenbomb]

I really think you want to keep the 3.0L Heads and not use the 2.5L Heads. Using the 2.5L Heads vice the 3L head will net you a CR of 11.2:1

The 3L Heads will be at 10:1 or somewhere close.

 

[DanG]

3L heads, P&Ped, port matched, reduced compression (9:1) pistons, Pauter rods. Done.

That's assuming you can find a supercharger with the revised jackshaft, as they are no longer being made. The better route is ADC's turbo kit, but it's more expenive. Total cost? Around $15k for everything to do it RIGHT.

I know. I've done it.

 

[Instigator]

Originally posted by: DanG
3L heads, P&Ped, port matched, reduced compression (9:1) pistons, Pauter rods. Done.

That's assuming you can find a supercharger with the revised jackshaft, as they are no longer being made. The better route is ADC's turbo kit, but it's more expenive. Total cost? Around $15k for everything to do it RIGHT.

I know. I've done it.

w3rd. I chose 8.5:1 C.R.

 

[DemonSVT]

I see no need to lower the oval port's ~10 to 1 compression ratio. The S/C does not spool up as fast even with smaller pulleys. You can use the extra CR for a stronger curve and better response.

If you really want a little drop in cc's you can get a few tenths drop from chamber work. Remove any sharp edges and potential hot spots.

There hasn't been a S/C engine with the oval cams but the Vortech really likes the SVT cams. They are more inline with it's higher rpm operating range.

 

[BLACKFXGT]

I see. And what if I want to stay N/A with 2.5 heads which cams would be ideal? Also the vortech kits are no longer made?

 

[BBOX]

If you want to stay all motor your best results are going to come from using SVT heads and cams.

 

[DemonSVT]

Best NA would be using an full oval 3L engine, custom cams, and custom pistons raising the CR. Also running race fuel 24/7.

 

[YOSLVR442]

i would agree with Demon on that one!!! :thumbsup:

 

[BLACKFXGT]

How does one know if it's SVT cams? Is there a number or symbol to look for on these cams

 

[DanG]

Orange stripe + large pitch cam sprocket = SVT.