Don Terrill’s Speed-Talk

With stock or a tad better flowing heads you should have no problems with 8 psi of boost in regards to the block or the main caps. These heads are basicly 351M castings and I recall doing a few porting jobs some years ago for two V8s, and with stock V8 valve sizes I had them topping 270 cfm@28"...

I Think the gear to gear clearance is the same .004 to .006 as the gear to cover clearance.

If its the 2.02" set that flows 5 cfm more than the added compression from the bigger valve will be a win win . If the 1.94" set flows more( which I have seen on re-worked valve seats) than use them. Has a back cut been added to both size valves? A good tall margin on a intake valve that m...

Times 3 along with the last two posting! You can have a motor that makes great HP but takes a ton of time to get to those rev`s! The right amount of velocity is key in getting a motor to rev fast. If you are building a motor for just Bonniville times than you can take libertys with the so called sta...

Oil into the pan and not any steam out the exh may very well not be a cracked head. You may have just cracked, or blown out one of the inatke manifold gaskets at a water crossover point . Stroking the motor for more cuibic inches or supercharging it will add more low end power during the rebuilding ...

I always thought that by now we would have, or someone would have made aluminum heads with incertible and replacible combustion chambers that have the valve guides as part of the casting. A metal type O ring seal of the same type used for cylinder fire ring seal could be used to seal the chamber for...

Gunk offers 2 or 3 off the shelf products that seal as they are promoted to do. My every day ride had a water to cylinder leak along with water to exturnal leak both form the head gasket and both where sealed over a year ago now . The stuff is some 30+ bucks a bottle but well worth it. Put the motor...

You only have to cheat enough to beat the other cheating competitors!
It a fact of life.

The higher ratio rocker will have the cup for the push rod closer to the flulcrum point. Head wise unless the valve to throat ratio is already at 91% its unlikly you will pick up any additional high lift flow with the 2.05" valve. However, if the seats are sunk from two or more valve jobs under...

CSRs web site should tell you.
Other than the starter, the water pump pulls the most current so you at least the same gauge wire that the pump come fitted with.
I have seen tons of guys at the track trying to pull 8 amps thru a 18 gauge wire feeding the pump and they wonder why things melt and pop!

The combustion chamber in those latter casting number low comp heads you posted about make less power out of the same givem amount of air flow. Remember an engine is nothing more than a air pump, 260 cfm thru a 180 cc port along with a 9 to 1 comp and a cam of no more than 222 duration on the intake...

A prime concern with exh port working well is to not loose any added low lift flow gained thru re-work (up to .300" lift) by shotting for the ulitmate in high lift flow. Also a common mistake on the exh side is to exactly match the port outlet to the tube size used. The floor of the port should...

The exh can be made to go over 200 cfm but it take alot of hard to come by detail work in conjuction with the needed valve job specs. Note that with the 186 heads producing intake flow numbers over 265 takes you to the tiping point where you will start to drop off some of the lower lift flow range n...

If they started out as heads fitted with 1.94" intakes and the chambers where not unshrouded for the 2.02" valves they flow about 210 to 215 cfm@28". I have ported these to 265 cfm@ 28" with the avaerage amount of rust and core shift they have after all these years of use. One ra...

Get in touch with TA performance, as they can likly help you out.