Now I can see why sometimes just 'throwing' in a big cam and not getting much improvement is a strong possibility when not doing any headwork by someone like this who knows the specs
Just picked up a set of 049 heads today. Went to a local junk yard, set about looking for the 781s because they are more plentiful, but was very happy to find the 049s. To me, already having a big domed piston, the 049s having a slightly larger bowl will service to,lower my compression hopefully where I need it. I ended up trading a th350 transmission I picked up the day before, it was still in the back,of,my truck, traded for the heads even. I had 100 bucks in the trans.
I'm thinking that on a dead stock truck engine rebuild this might be something to do since you will be running the stock truck cam. Might perk the old girl up a little.
@@daltonanderson5116 stock 088 heads, no porting, 2.19/1.88 valves and the cam is a Howard's hydraulic roller camshaft. What camshaft are planning on using? What's your hp goals?
I bought a set of oval heads with the big valves installed 2.19 intake and I will try to get into the 280 cfm range at 5.43 lift, my ultimate goat is 550hp with 10.5.1 compression. I have a single plane 4150 intake, 1050cfm holley on 454 cubes internally balanced. I would like to hear your thoughts.
this is a good example of putting too big of a camshaft in a motor that the intake ports have negligible gains at .600 lift. there's no gain in putting a .700 lift cam with this head because the intake ports stop flowing well at about .500-.550 lift.
If you stop your cam lift a 500 it will only hit it at the top of the lobe while if you were to have it higher it would hit the 500 mark twice, when its coming up the lobe and down the lobe, would be especially better with a flat tappet since the lobe are less agressive.
I’m working on building at 496 with 781 heads. I want to put larger valves in and use a 292h (292/292 advertised duration 550/550 lift) think that will work well I don’t plan on porting because I’m not comfortable enough to do it
Interesting, so would that mean since the RECT. port heads came with 2.19 they are superior to the oval? I remember many magazine and racers discussions on the oval VS rect. head choice
No, I just worked on a pair of 990 Rec head and the factory 2.19 valve job was a joke. HAD to take them to 2.25 to get any sort of 3 angle on the thing, factory was a very sad bowl area.... :(
I am 62 and remember 'back in the day' people getting a substantially bigger cam and throwing it in and wondering where all the added performance is--now I see why
Rect port heads out flow ovals by a mile!! You can buy much better aftermarket heads today for less than you will invest in an old set of iron rect ports, but if you have a set, by all means use them!! If you're building a below 6500 rpm street rod, then oval's are a much better choice.
Their is no need to shut down the bench between lift adjustments , I had a SF100 in 1970 and a SF600 which was serial # 11 , another mistake he makes is you never flow the Ex, w/o a pipe , the numbers will always be wrong,
