Performance cylinder head rebuilding for import & domestic heads. High performance head porting, polishing, rebuildingPerformance cylinder head rebuilding for import & domestic heads. High performance head porting, polishing, rebuilding

Performance cylinder head rebuilding for import and domestic heads. High performance head porting, polishing, rebuilding
Dodge V-10 / Viper

We recently ported an iron V-10 head. In stock form it flowed 203.3 cfm. When we finished it flowed 224.4 which is a theoretical increase of 54 H.P. During that same time we had a Viper head in the shop that had been ported by a local competitor to the tune of around $1,000.00. Understandably, the customer did not want to sink more money into that head so we left it alone. We did, however, test the head and it flowed a disappointing 212.6 cfm. The moral of the story is: be careful who you let port your heads. Whether you choose us or another shop, make sure you pick a shop that has experience with Vipers as well as with a flow bench. Shop around. Compare our prices with that of our competitors. We pride ourselves in providing the highest standards at the most competitive rates.




If you've visited any of the other pages on this site you may have noticed that we normally offer 3 different stages of porting options.  We have removed the stage I and II options for the Viper head because it really takes the stage III level of porting to get this head where it needs to be.  We realize that if you've gone to the trouble of removing the heads from your Viper for performance enhancements, you are most likely looking for all you can get and you won't be happy with anything less.

We're currently seeing around 280 cfm on our ported Gen II heads where they were around 225 in stock form.  That's a theoretical increase of 140 H.P!

Stock Valve Job

** Competition Valve Job

Replace valve guides
(includes parts)

Machine seats for larger valves

Resurface (iron)

Resurface (aluminum)

Volume chamber & mill for specific compression ratio

Surface exhaust manifolds

Port / Port match intake manifold





$50 ea

$60 ea


$35 ea


* Stage III does not include cost of valves

** Competition valve job is any deviation from stock ie: larger springs, longer valves
If it fits On or In a VIPER
Stage III: $1,500+

Competition port job - full competition port and polish complete with larger valves installed *and chambers reshaped to accommodate the larger valves. The stage III port job will increase your head's efficiency by approximately 55 cfm @ 28" which calculates to a gain of around 140 H.P. on a V-10

              Stage III Package:                       $2,895

Package includes stage III port job, stainless Manley 2.02 and 1.6 valves, Comp Cams 930 dual springs, Manley titanium retainers, new 10 degree locks, surfaced and ready to bolt on with a guarantee of at least 280 cfm on the gen II heads. Your heads or exchange.

Here's a Viper cumbustion chamber in stock form, notice how
close the chamber wall is to the edge of the valve. If the larger
valves are installed and this chamber left unmodified, the head
will actually flow less air than with the stock size valves.

Usually valve unshrouding can be done quickly and easily
in a valve guide and seat machine using radiused carbide
cutters, but because of the shape, location, and design of this
chamber, all this work must be done by hand.


In Loving Memory

Peter A. Agalzoff

October 02, 1951 - July 05, 2003

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