Flat tappet cam

[1969CoronetR/T]

I got a set of ported stage II Indy EZ heads and a new flat tappet cam with the following specifications for my 1969 Coronet R/T with a 440 cid engine:

Duration .050: 241 247 with a 110.0 lobe separation. ADV DUR: int. 285 exhaust 297. The valve lift is .545

Stock converter for now.

Is the .545 valve life sufficient for street use and mild drag use or would .575 work better in this build?
Also, I may be changing over to a roller instead of using the flat tappet that I have new. What would be needed to change over to a roller from a flat tappet? Would any of you guys keep the flat tappet instead of converting to the roller? Lastly, Would a 2500-3000 stall fit this cam better than the stock converter?
Thanks.

 

[GTX MATT]

Yes on the extra stall, you want/need more than stock with that. Its not anything crazy, 225ish is ok on a stock converter, anything more starts to become noticeable. Roller cam? Depends on how much money you want to spend and how much power you want.

Don't worry as much about lift, worry about duration. Your duration is good for street/strip use. The lift is pretty aggressive as well.

 

[1969CoronetR/T]

Thanks GTX MATT. What do you mean by 225ish on a stock converter?

 

[GTX MATT]

225 @ .050 will feel OK with a stock converter (Hemi/383/340 converter better than 440 converter also), much more than that and you will need to raise the idle a little high and it won't feel as strong coming off the line. Of course it depends on your tuning skills too. 241 will work, it will run and go, but it wont feel as good.

 

[1969CoronetR/T]

I forgot to mention that my rear gears are 4.10 with a 950 cfm AED carburetor.

 

[383man]

Its not a bad cam but I would never run a stock converter with it. I use Indy EZ heads that are just the basic EZ heads with bit of mild porting. I use a more agressive flat tappet cam as mine is a custom grind for my combo as its .585 & .592 lift with a 110 LSA and it has 264 & 270 duration @ .050 and I have it in the eng on a 106 installed centerline. I use Hughes roller 1.6 rockers that puts the lift aroung .630 and I use a Dynamic 9.5 street/strip converter that will flash about 4200 at the track and it drives like a normal converter on the street. Ron

 

[1969CoronetR/T]

TCI recommends using a 2800 stall with my cam. My engine builder recommends 3000 - 3200 range. Maybe I will split the difference and go with a 3000 stall.

 

[1969CoronetR/T]

I have conflicting carburetor sizes. The engine builder wants me to use a AED double pumper 950 cfm, but the dyno guy (he also builds engines) suggests I stick with a 800 cfm Holley. Using the a cfm calculator at 6000 RPM with a 440 I come up with 840 cfm. Would 950 be too much carb?

 

[383man]

You can tune the 950 to work fine but also I only use a standard Holley 850 DP on my 493 that make around 600 flywheel hp and pushes my 3700 lb 63 to 10.70's @ 125 and has worked fine on my 493 since 2011 with no problems.
Myself I would look into a different brand converter then TCI as I have not heard alot of good about their conveters. Its up to you but its just a little friendly advise you might consider. You can always call others like ATI , Dynamic , Turbo Action , Ultimate , PTC , Coan just to name a few brand converter companies that have good reputations. Just a suggestion you may consider. Good luck , Ron

 

[1969CoronetR/T]

Thanks, I called TCI because they are a division of Comp Cams and I have their camshaft. The builder wants to use J.W. Converters, but I will ask him about the other brands. I am thinking I will use a Holley 850 Like you, 383man. 950 seems too large, 800 seems too small.

 

[GTX MATT]

950 actually has smaller venturis than an 850, its kind of gimicky and confusing. The 950 has the same venturi as a 750 actually. The 850 and 950 have the same throttle bores though. The 950 should be able to meter fuel better on a smaller engine but wont flow as much as the 850. I've never owned a 4781 850 DP, but I've heard they can be a little difficult and tend to run rich because of the larger venturi and a good friend of mine had alot of trouble with one and went back to his 800. I know Ron had good success with his when he had it on his 440 but Ron's got more experience than most too. Just something to keep in mind. That said I wouldn't hesitate to buy one, I think you may be better matched to an 800 or the 950 though.

 

[1969CoronetR/T]

I just ordered a Holley 850CFM ULTRA HP with mechanical secondaries. Now I need a set of Smith Brothers push rods after he measures for size.

 

[GTX MATT]

Lots of tunability on that carb, get a wideband and you can get that thing tuned in on a dime.

 

[1969CoronetR/T]

A few pictures of the Indy EZ heads with stage II porting.

 

[Budnicks]

I persoannly would go with your engine builders suggestion of the 950cfm too

A few pictures of the Indy EZ heads with stage II porting.

maybe a photo looking down the ports intake & exhaust,
showing the business side of where/how it works/ported,
I'd be curious to see the pockets under the valves too, see what they actually have done
nice Indy EZ heads I'm sure thou

 

[1969CoronetR/T]

I will post some better pictures this weekend.

 

[Budnicks]

I will post some better pictures this weekend.

did they give you flow #'s & where the flow #'s are @ what RPM's ??, just curious

 

[1969CoronetR/T]

Yes, he has a flow bench. I have to ask him where he put the numbers.

 

[383man]

You know I never took any good pics of my EZ heads when I built my eng. I do remember that I bought my EZ heads from Dwayne Porter and he just opened up the end of the ports to maxie size and we blended the bowls as thats about all he did to them. I remember they did flow 329 @ .600 on the intakes and about 229 on the exh. Here is a pic of the eng as I was building it. Ron

- - - Updated - - -

Ah I did find this pic I forgot about. You can see the intake ports some and sorta see the D-dish pistons I used to keep my comp at 10.6 as it would have been to high with flattop pistons which I had at first. I had flattop pistons because I was going to use the 84cc Eddy RPM heads but changed to the 75 CC EZ heads and had to change my pistons then so I could still have quench and stay pump gas friendly. It worked good as I traded the flattop pistons to my brother for his 1 year old Hughes 1.6 roller rockers and shafts. Course I had to buy the new dish pistons. Ron

- - - Updated - - -

950 actually has smaller venturis than an 850, its kind of gimicky and confusing. The 950 has the same venturi as a 750 actually. The 850 and 950 have the same throttle bores though. The 950 should be able to meter fuel better on a smaller engine but wont flow as much as the 850. I've never owned a 4781 850 DP, but I've heard they can be a little difficult and tend to run rich because of the larger venturi and a good friend of mine had alot of trouble with one and went back to his 800. I know Ron had good success with his when he had it on his 440 but Ron's got more experience than most too. Just something to keep in mind. That said I wouldn't hesitate to buy one, I think you may be better matched to an 800 or the 950 though.

You and your friend are correct. My cruise was a bit fat for me as I wanted to keep my plugs clean when cruising alot. I did lean out my part throttle cruise some to clean up the part throttle cruise which is where my gas pedal is alot of the time driving on the street. But I had my full throttle runs tunned where I wanted them so I did not lean the wide open throttle any just my part throttle cruise. I even did some jetting at the track as I leaned my primaries some and fattened the secondaries to keep my full throttle mph and et as fast so not to loose any wide open throttle performance. And as I am sure you know I always size and mike my jet sizes as Holley jets are not the size written on them and can get confusing so I drill size and mike my drill sizes on Holley jets all the time. I also added some air into my part throttle which was mostly still on the idle and transfer slot circuits to keep the cruise clean. But dont get worried as it was not as bad as it sounds because I have been a tech all my life and I like to try and tune my car to be as perfect as I can get it and I enjoy doing it. Hey I figure I spent most of my life learning how these beast work and trying to be the best I can with them so why not try and put some of that knowledge to use for myself. LoL ! If your 850 seems a bit rich (fat) when cruising and you dont feel real good fine tunning your carb just work with a good carb man. But by all means put it on the eng and see how it works first as it may work great right out of the box for you as like many performance parts you need to try it first because all combo's can be different and just because mine likes it one way does not mean yours will be the same. Ron

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By the way thats my old 906 headed 440 eng as its one of the only pics I have of the 850 with no air cleaner on it. As this is the 493 with the EZ heads. Ron

 

[1969CoronetR/T]

drooling...