2v to 4v headswap

97stanger · Apr 23, 2013

I have been reading on this topic and mostly everyone comes to the consensus that you should just buy a 4v motor. A lot of the threads I'm reading are older, and just wanted to see if anybody on here has any first hand experience in swapping 2v to 4v heads/cams/intake. I'm well aware of the type of work that would be involved (heads/cams/intake/throttle body/brackets/headers/supercharger piping/alternator relocation/bracket/timing cover/coilspacks/rails/etc). So I do understand its not just a swap done over night.

I'm more just looking to see if there is any more recent info/any true life experience for guys doing this.

I currently run MMR stage 3 PI heads, Bullet racing blower cams and a port matched Edelbrock EFI manifold with a 6061 sheet metal plenum. My power adder is a V7 JT, paxton FMIC, and a 50/50 meth system.

From my findings I also have read that putting 4v heads on a 2v block will lower compression. Anybody have any first hand experience with this?

As you all know, we get bored with cars and I'm just looking for another project to start and can imagine gains would be pretty dramatic especially at 20psi. Just looking to see if there are any newer updates on this common topic or if anybody on here has first hand experience?

Burninrock24 · Apr 23, 2013

Do you plan on porting the 4V heads? Otherwise you'd be much much better off with your stage 3 heads now.

Yes 4V heads lower compression. The combustion chamber in the B-series is 52cc, a 99-01 head is 54cc, an 03 cobra head is 52cc. A 2V PI head is 42cc.

Just also remember that there are 4 cams in a 4v. So whatever you paid for your cams, double it. And your top-end bolt ons won't work anymore either, so that's another cost factor.

Here's all the flow data you need to compare to your stage 3 heads.

MustangChris · Apr 23, 2013

sorry brotha. did a whole motor swap myself.

Did your 2v give out on ya?

Burninrock24 · Apr 23, 2013

If I were you I would just get trick flow heads. The intake port and valve angle is adjusted to flow better, the valves are bigger for better flow at low-mid lift, and you can basically choose what compression you want with them. They are better flowing than any 4v head and you get to keep all your bolt-ons including cams.

MustangChris · Apr 23, 2013

"better flowing than any 4v head" I call shinanigins!!!

what abour bare-bones B-head 4vs? No intake control rubbish, both port, etc etc etc.

97stanger · Apr 23, 2013

thanks for the info guys. Nothing wrong with my setup at all. Just always looking where I can make my setup more efficient and I know for a fact the little 2v is holding me back. After doing even more surfing on this topic, it seems like one hell of a swap. TONS of labor and tons of swapping parts from work I've already done. I've considered going with a better set of heads/cams but again dont really know if it would be worth the labor/time. I currently run MMR stage 3 PI heads and VT stage 2 blower grinds. I have stock pistons and valves so those are the biggest cams I could run without PTV issues. Has anybody actually done a comparison of going from MMR heads to ported TF's? I'm sure if I ran a more aggressive cam more power could be had, as my car starts falling off now around 6400 at 19-20 psi

vermilion · Apr 23, 2013

Mike remember where im at with power. i know if you went with a smaller pulley you'd be in there like swimwear.

97stanger · Apr 23, 2013

I run a 2.95 blower pulley and a 10% Innovators West, Thump Tensioner already Jason...

Burninrock24 · Apr 23, 2013

MustangChris said:
"better flowing than any 4v head" I call shinanigins!!!

what abour bare-bones B-head 4vs? No intake control rubbish, both port, etc etc etc.

Here are the flow numbers:

http://static.trickflow.com/global/images/chartsguides/t/tfs airflow twisted wedge 185 ford 4,6l.pdf

Which I got from: http://www.trickflow.com/partdetail.asp?part=TFS-51910001-M38

250 @ .500 and 252@ .600 lift.

And as you can see from above, those numbers are better than all of the 4V heads except the Y2K Cobra R and the Ford GT/GT500 heads. Which are 7 grand a piece new last time I looked into them haha.

They were done at different pressures, but stock for stock they are still touted as the better head. Especially when put on a 2V.

Now would it be more cost effective to get ported 4V heads? Maybe. But it depends on how much the new intake manifold will cost and the rest of the swap included. So it's a toss up really.

1997GT4.6 · Apr 23, 2013

Pointless to port B heads. Waste of money. On a B head Cobra at least. Not sure what effect that would have on a head swapped 2v. B heads flow really well up top especially with a centri.blower. If doing a head swap, C heads are better.

97stanger · Apr 24, 2013

After getting some more actual knowledge on whats involved with this swap I agree its not worth the hassle and $$$. What is starting to look more appealing to me is going from my MMR stage 3 PI heads and CMW stage 2 blower cams, to MMR's stage 3 Trick flow heads and stage 3 blower cams. Tons of more airflow through those heads and a more aggressive cam. All I would really need is the heads/cams and some new gaskets and still reuse my intake/plenum setup. Also its nice with the Trickflow heads that I wouldnt have to get my pistons notched with that large of a cam....very tempting

What kinds of gains do you think are to be had from going from worked PI heads and stage 2 cams (533/571, 220/230, 114lsa) to ported trickflow 2v heads with more aggressive cams?

Burninrock24 · Apr 24, 2013

I'm glad we could help you come to a decision! I think you made the right one as well.

What HP are you making now?

97stanger · Apr 24, 2013

Right now the car makes right around 600rwhp on 19psi at 6400 rpms through an automatic. What I really need to decide is if swapping my heads/cams for ported TF heads/more aggressive cams is worth it. If i'll gain 20-30 hp no way

vermilion · Apr 24, 2013

2.75 pulley will make your pants happy. you have all the rest

KillNThrill24 · Apr 25, 2013

Since they are both stage 3 ported... My GUESS would be whatever you would gain from going from a stock pi head to a stock TF head would be your gains. Could be wrong, and most likely am, but that's just my guess. And factor in the larger cam... O I dunno if you gain the supposed 40hp or so from pi to TF, then I'd say with the head upgrade and cam upgrade.... Maybe 60? I don't know enough about that stuff to make a proper answer.. Just throwing numbers out there

Burninrock24 · Apr 25, 2013

Well there was a post on another forum about a guy making 645WHP, 652TQ on a MMR900 w/ Stock Trick Flow Heads, Sheet metal Intake w/ Turbo @ 14psi from ON3.