Whats up guys i had a question. I got a good deal on a set of navigator heads and was planing on building a new motor with them. Are they a down grade when compared to the 03-04 cobra heads and if so would be a big downgrade?
Navigator heads
- Thread starter Vicious805cobra
- Start date
The 5.4 DOHC heads actually have larger ports and flow better than the 4.6 DOHC heads the Cobra had. Of course that means they won't mate up the same as 4.6 DOHC heads without some adaptation.
You really need to get your facts straight. Yes the ports are about 1/2 wider but they do not outflow the 03/04 cobra heads.
The intake ports are 9mm wider, and I could have sworn they flowed ~260 cfm @0.500" lift compared to around 235 cfm on the 03 Cobras? Or is that number for the GT heads?
The navi heads certainly aren't perfect. They've got less of a short side radius compared to the 03's, and a thicker divider on the exhaust side, but they've got a much wider runner, and consequently a higher runner volume.
The Navi heads flow 218 and the Cobra heads flow 233. The GT's flow 274.
Correct.03/04 heads are one of the best flowing DOHC.
GT Heads>03/04 Heads>B Heads>Navi Heads
If you get a good deAl on navi heads,buy em.i could get navi heads for about $200.a decent port job will be about $750 and will outflow 03/04 heads by a fair amount.that will put me around $950 compared to $750+ for 03/04 heads.
Navi heads if your on a budget
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