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Discussion Starter · #1 ·
Went to go look at this car that has a 1999 truck motor vortec 350 in it that i was thinking about buying and this is what i know about it, has intake holly carb 650, comp cams 2100 magnum double timing chain, howards cams rattler camshaft hrs 118001-09, proform parts 66907/66907c proform extruded roller rocker arms. 1 belt set up. Hasnt been bored. You think this a good set up??
 

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Why did they backfit a hydraulic flat tappet cam into what was a factory roller cam engine??
That's a dumb move.

Looing up that part number shows 227°/235° Duration @.050", .480"/.488" lift, 109° Lobe Separation Angle and 103° Intake Lobe Centerline....hydraulic flat tappet.

Proform tends to be a cheap rocker arm, but probably ok within the parameters of that cam and the necessary valvesprings.
 

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The change to a flat tappet cam isn’t the direction I would go, if the cam doesn’t wear lobes it’s fine.

Proform rockers are fine, not what you’d take for serious racing but very streetable.

Overall I’d say yes good deal.

Bogie
 

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Discussion Starter · #4 ·
Why did they backfit a hydraulic flat tappet cam into what was a factory roller cam engine??
That's a dumb move.

Looing up that part number shows 227°/235° Duration @.050", .480"/.488" lift, 109° Lobe Separation Angle and 103° Intake Lobe Centerline....hydraulic flat tappet.

Proform tends to be a cheap rocker arm, but probably ok within the parameters of that cam and the necessary valvesprings.
Yea i thought that was strange as well being a roller motor witj a flat tapped cam
 

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If you can afford it and get the machine work done, get the vortec heads to take screw in rocker arm studs as the pressed in studs with aggressive cams and anything outside of stock and higher lift can sometimes pull them out because of the extra spring pressure needed to keep the valve train under control. There is a kit you can get to do this yourself but I don't know right off hand what it is but below is a video on the part of it being done. Good luck on your build and it will sound good and run good I am sure with the right matched parts.


 

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Discussion Starter · #11 ·
Exactly so what you think about the new route im going?? 350 block with vortec heads,edelbrock perforer intake holly carb 600/650, 270 comp cam, double roller timing chain with the serpentine 1 belt set up . want just a nice cruiser weekend toy
 

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This is just my opinion and others will differ. But if you go that rout and make sure you use the right pistons to get the proper amount of compression and make sure your quench is good and get the proper stall conertor to use with an automatic transmission if that is what your planing on using and you have a proper rear end setup to match with the transmission and the engine is matched well around the cam and the heads are worked to handle the cam then I would say you would have a nice mild street ride that should not be to bad.

Depending on your budget that will factor into a lot of things and I have at times in the past short changed myself and put a build together that is was good in some areas and not in others and ended up later on not liking what I did so I ended up doing a whole other build once again spending more money then if I had just waited and saved a little bit longer then I could have done it the proper way I originally wanted to.

Yeah some may argue about some of this or that on some parts but that is why I always say there are always different options you can choose and still have your build be within a good range of matched parts. One can always change a few things and the build is not out of being a good build such as carb size to a certain point and other factors. I won't get into a lot on that part but I on my build have left some power on the table on a few choices I made but I also don't have a mismatched bunch of parts thrown together as well. My build is conservative and I know I leave some on the table for power so called to speak but its not much and I don't race mine or take it to the track but just cruise with it and get what I want out of my build with no problems.

Like I said there are certain trade off with things when you get into anything above stock. If you can someday afford a roller cam build I would suggest that over a flat tappet cam but when your on a tight budget you do what you can do but always try to have a plan for improvement and the options to do so with your build if you choose to do so. Also your not always going to get everyone to agree on this part or that part and be against this or that so I leave a little wiggle room but not to much when it comes to recommendations but its up to you to make the final decision on your build as it will be you who will be the one to enjoy it and not us.

Take your time and don't rush things and short yourself either as I have been there and done that and cost me much more later. Just a basic mild build does not have to have the biggest everything for it to be a good build. There is no perfect build where all is the right size this or that. That is why you can get all difference combinations on stuff and so many parts you can choose from. Don't let some folks make you feel like your build is junk and no good just because of on part they don't agree with and even though your build might still be a good build but sometimes some folks can make one feel like there whole engine is wrong and its not.

There will always be different opinions on what a good build is considered but if you match stuff up good from front to the back and stuff is all within reason and acceptable then your good. You can always have a different transmission and different size carb and gear ranges to effect things and I always build around with what I am honestly going to do with my ride and how am I going to drive it and make it for that and not the most power and the fastest speed I can get as if I don't race it I don't have to get every last ounce out of it but I also get a lot from it still and leave only minimum power on the plate. Don't always go for the bigger is always better thing as it can come back to haunt you.

Keep it simple and matched good with the engine on the heads and the cam and correct compression and the proper rotating assembly and the drive train and you can have a nice cruising ride that won't have to be something exotic just to have a good time driving it and being satisfied. Letting negative influence from someone get the best of you such as saying this particular carb size is wrong or this cam is not the perfect cam for your build and if you don't use this or that then your build is no good as I let a persons comments once about a cam I had that it sounded like a stock cam.

I bought a comp big mutha thumper hydraulic roller and after three months I tore it out and sold it as I hated it. Never let a person deter you from your build because they might not agree with some of your choices. The most important thing is making sure what choices you do make will all work with each other and run well while still leaving room for other options in the future if you plan on wanting more if that is the case and if not then make it as best as you can at the time you have it built but if it takes some extra time to save to get it more of the way you want it so you don't have to cut corners and wait a little then I suggest you save longer if need be to get the proper stuff of what you want.

On my 350 build some would not agree with my carb size or my intake that I am using or a few other things on my truck but it is all matched well for what I do and is not a band aid build and a bunch of things thrown together but is a well though out build that I have a lot of years different builds to know a good setup without it being a bad build at all. Some might agree with some of my build and some won't but that is the nature of the game of hotrodding. There is always options for any said build that you can tweak this or that and still have a good setup. Unless for all out racing, anything on the street does not have to have all the biggest and baddest on every single part.

Do your homework and get some books on small block chevy builds and learn how different combos effect what and it will help open up your mind and knowledge and allow for you to make good choices the first time. Just take your time and don't rush and go from there. Make your build for what makes you enjoy it and what you want from it and don't worry about pleasing everybody in the crowd as some will say yeah and some nay. Just make sure its matched well within reason and don't cut corners and be wise on your decisions and don't worry about every single opinion as yours is the one at the end that will matter the most.

Trust me been there and done that before and I ask for advice and reason with the suggestions as possible options but weigh the good with the bad and make the best reasonable choice for myself.
 

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With that cam I wold not run anything less then a 2000 plus stall convertor. I am running a similar size cam in my 350 and its a hydraulic roller with 268/272 220/[email protected] 510/510 lift with a 114 lsa and and a 2000 to 2300 rpm stall convertor and it runs good with my truck and turbo 350 with 3.42 rear gears. I know comp cam says you can use a stock stall but I would want to at least go with something more so you get more out of your engine as a stall convertor being to small or to big can make or break a deal.

On my previous 377 de stroke build I had, I had a bigger camshaft when I had it first built and it called for a 3000 plus stall convertor and when I decided to mild the engine down some and changed the camshaft I went with the grind I had above but I did not have the time to get a slightly smaller convertor for my cam and did so when I just got my 350 Dart shp build done recently and this time I had the extra to get the torque convertor that works with it.

It worked with the 3000 stall ok but was a little bit soggy at that point being to lose since I had a smaller cam by a few sizes compared to what I started out with. I knew I was going to eventually do a 350 so I did not bother to get a convertor for the 377 as it was already in the plans to sell it. I saved for almost two years to get my 350 build the way I wanted it. A mid 2300 to 2500 rpm stall would not hurt it and would not need anything bigger then that at least that is my experience with different builds over the years.
 

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When you run a bigger stall convertor then stock you always want to run an external transmission cooler to where it gets good flow to help with running bigger stall convertors and stuff and that is how to keep your transmission from burning up. Depending on the application some folks will run an electric fan to cool the external transmission cooler but I have had builds way more wild then what your planing to do and all I had was an external tranny cooler in front of my radiator with a 3500 plus stall convertor once on a 86 chevy s10 and a th350 with nothing more then a shift kit installed and I had around 425 or so horsepower and I ran it like that for over ten plus years and drove it in and out of traffic and my transmission never failed me or gave me any trouble.

If you get a stall convertor around just over 2000 rpm it would not burn up your transmission if you use an external transmission cooler. Below is an example of what I run to keep my transmission cool and it works fine without any electric fan type setup. I just have it in front of my radiator between it and my front grille and the fan pulls air through it and I have a temperature gauge on my transmission and it has never gotten hot even with a previous small 10 inch 3000 stall. The size of the convertor plays a part as well in how much heat things will make. The bigger the stall and the smaller the size then the more heat it will make as it is more loose and slips more and holds less fluid.

My stall convertor that I previously had was a small ten inch size but mine that I have now is a stock size for a th350 and its a 12 inch size so it hold more fluid and will not slip as much and be loose like a smaller diameter higher rated stall. Get you a good quality 2000 plus stall without going to much more then that and put on the biggest external tranny cooler and it will work fine. There is more then what I posted but that is the basics of some things. Below is just an example but not the exact one I am using. The stack plate ones are more better then the tube and fin style from what I heard and more durable as well.

I can't tell you anything about the whole lockup stuff on transmissions as I am no expert on that but I do know they make kits to lockup the stall convertor on the 700r4 aka 4l60 and yours would be similar and I would research that part and I highly doubt that mod would burn it up if done with the right parts and way. There are legit kits out there but you have to be careful on what one you use. I have seen some performance 700r4's with the lockup feature taken out and make the transmission like a non lockup style. I am sure there is some more information there and I don't know what that is but I have seen them sold like that.

If it was such a thing that it would burn up the transmission then why would they sell one like that. TCI and some other names were the ones I have seen that on before. I just prefer a th350 myself. What you got can be made to work. The statement above is most modern mechanics of the average run of the mill know nothing about performance stuff especially the stuff we run of the old school variety.

 

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Dont want my trans to burn in 4th gear so was told the lock up kit will be good but my mechanic friend said just go with a smallet stall?
Not necessarily.

Converter lock up clutches are not very strong. The factory program recognizes this whether that a mechanically switched system used on the late TH350 or the TH700R4/4L60 or the electronically controlled TH4L60E and 4L80E.

There reaches a point where high stall converters don’t even offer the converter lockup clutch as it is expected that engine power or end use of the vehicle provides that such a device lacks the strength or usefulness for the application.

A high stall converter in many ways can be compared to a slipper clutch. These are there to allow the engine to get up into its power curve without and before fully loading the crankshaft. This is something of a race between the engine’s ability to make power against the need of the vehicle to accelerate with the power available. Actual stall speed is a variable between power in and resistance to that power on the out side. The advertised stall on any converter is based on some test condition where if the output is locked against rotation some input power, generally unstated, can no longer gain RPM. Needless to say in the maximum stalled condition the converter and its contents is being destroyed. So you cannot go to this corner of the envelope and just sit there.

Another practical application of high stall on the street is if your running a racing cam that requires an idle of 1200 or more RPM while sitting out a traffic light you won’t need to apply so much foot pressure on the brake pedal that your foot turns black and falls of your ankle before the light changes.

Bogie
 

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but my mechanic friend said just go with a smallet stall
Most mechanics know Jack about performance.
That's a fact.

He's only right if he meant smaller diameter converter, which will have higher stall speed.

If he meant smaller as in lower stall rpm, then he is dead wrong.
The context I got from the responses in this thread that he meant lower stall rpm.
That'll just make the car a pig.
 

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Take the advice and don't go with a too much of a low stall or you will pay for it. Trust me I have been there and done that before with a bone stock 350 when I first got the hot rod bug and the wanting the rough idle sound and this was back in 98 when I was just a young buck back then at just 22 years old and did not know any better and my old 86 s10 I used to own I had a stock 350 and put a big comp cam 292h 244/[email protected] 500/500 lift magnum flat tappet cam and I had a th350 and a very small convertor and it was so horrible that I did not know any better but my idle was 1200 rpm and when I shifted my transmission into drive or reverse it would chirp my tires on blacktop and at the stop sign like Boogie said I had to pump and my brake pedal was horrible and just a lot of problems until I finally got the right stall convertor to go with the cam and also changed out the cylinder heads and intake to match the camshaft.

It just clunked and was hard on my transmission and I had a lot of bucking around town as well because of improper stall speed for such a big cam. I had only basically just a hair above stock. After I got what it wanted then it was a whole other world and ran like a beast then. Like above of what they said and getting a proper and better cooling for your transmission will go a long way.
 
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