Discussion in 'The Driveway (build threads)' started by blazinzuk, Apr 30, 2012.
Great project. I will be following it.
I thought the same thing Heath, but I know so many guys running aluminum roller rockers with no problems. I know some guys who have had problems but they are few and far between it seems.
Going to have to see if the comp steel ones are in the budget.
I am going to ask the machinest about doing a little bowl blending, I have never done any kind of head work and I don't want to mess things up.
I know I can't afford for them to do it but some mild bowl blending seems pretty easy to do.
Everything that needs replaced on the heads will be, These heads I thought about just putting on the new short block but when I did the ol WD-40 trick with the valves closed I decided no way, way too much leakage coming through.
I am very excited to have this thing going and while the suspension will probably be in a couple years I do plan to start getting the 73 front flip ready to bolt on this winter
Eric for the bowl blend, if all you do is concentrate on smoothing the machining marks and rough spots, and don't try to reshape the ports there, you can't go wrong. (as long as you don't grind on the valve seat surface) You just want a smooth transition from the cast port all the way to the valve seat, no interupted flow or bumps or edges. I just use a die grinder with an oval carbide bit.
You may consider a gasket match of the intake ports and intake manifold as well with a mild gasket of course. The goal there is to smooth the flow between the intake and heads. With your low RPM you don't want to remove too much material or reshape the port really. The most gain will be from the bowl blend though. Also, a lot of times where the valve seat cutter cut into the head from the chamber side, there will be a step right outside the valve seat, I like to knock that off and smooth the flow into the chamber, very mild, and be consistent from one chamber to the next, you don't want different compression ratios. When working in the combustion chamber, if you can get your machinist to grind an old set of valves very thin so you can drop them in and they sit real low to protect the seat without being in the way, that helps, but it isn't necessary.
I've been running China made Speedway aluminum roller rockers in my 1988 V10 Suburban for a few years with no problems at all (yet).
Here is a set of BBC Stainless Steel roller rockers for cheap.
They are only $10 to $20 more than the Speedway aluminum ones.
These are the ones I am running on my Vortec heads.
Thats funny, I was going to say those are barely cheaper than the comp pro magnums I put on my BB, but after looking I see they stopped making them, now they only have the regular magnum, or the ultra pro magnum hollow type that are very expensive.
One thing to keep in mind Eric, roller rockers are a little noisy, they sound almost like a solid cam. I don't care myself, but if you do you might want to stick with a roller tipped set. (actually, I've never used a roller tipped set, are they still quiet like a regular stamped rocker?) At least a roller tipped set will reduce valve guide wear because of the reduced side load friction on the valve stem. You only really hear them at idle though, if its above idle its hard to tell.
Honestly I have Roller rockers on my camaro and stock rockers on my truck. I don't think I would waste the money on a truck motor. I would put the extra money toward a 4.25 cast scat crank.
That is a valid point, although I don't consider roller rockers a waste of money(less friction is always good), I would have to agree the stroker crank would add more torque than the rockers if he has the money for the balance job and hasn't already bought the pistons.
You have to remember this has been a process for me.
Originally was going to use the heads as is, in fact I was going to use some smog heads that were already on the motor. So I got the bottom end done out of necessity because a ring broke when putting the pistons back in ( unreabuilt motor) left a huge scratch in the cylinder wall. But then I got the block back and realized how bad the heads actually were, no point in putting crap on something new being as it will make the new part not last as long and I don't want to spend the money twice.
In addition to that before I spent alot of money on rotating assemblys and balancing ( I have had bad luck with "factory" balancing always had to have it rebalanced) I would have seriously looked at picking up a 6.5 turbo and doing the vintage air ac.
If I could start all over again I wouldn't have done a single thing the same up to this point.
And now if I can't get this medical bill ( ER visit for kidney stones) figured out well its going to sit again
I agree the rockers will help but not as much on a tiny rv cam as they will on a mech roller. I just think the place to spend money on a towing engine is good heads, and displacement. Pick the cam for the rpm you are going to run and don't get all worried about hp. Tq is king and what pulls down the highway.
I have something to add about the summit roller rockers. I put a set on a 350 I built for mine/my best friends 84 K10. It's got 39k miles on it so far and no trouble ffom the rockers. With all this rain we've had around here. I'll bet that that engine is somewhere around 6k right this minute and it will be there till all the mudholes are dry or he breaks another 10 bolt.
My cam is picked for the rpm range I will be cruising at. Already have pistons and have for a while, heads will be 781 heads.
Machinest is getting prices on a bunch of different way to build the heads but its lookin like I need to get as cheap as possible so probably will end up being stock rockers for now, which is a bummer but will be just fine
you need any stock valves, rockers, studs, or guideplates?....I got a can full of em.
Good luck Eric, I hope the medical bill gets sorted out in your favor.
Cant wait to see more updates on this, I love these crew cab duallys!
So finally getting the heads to the machine shop in the morning.
Couple of things have put a pretty big gash in the budget, my deck started to fall apart the wood underneath is rotting and had to pay some medical bills.
I think i can get it running and driving though.
Been working on some small stuff.
Going to start putting the interior back together this week too.
Hopefully many pics to follow
So the guy I took the heads too a guy ( kind of a friend of a friend) decided he needed my money more than I did. He was supposed to do them after hours as a favor to me. I had done some welding for him in the past, always seemed like an upstanding type of guy, anyhoo gave him 400 bucks to get going on the heads and well found out today ( late today) that he had skipped town after doing the same thing to several people. Going to get the heads tomorrow not done 400 bucks shorter than I was before.
Dammit Eric, that really sucks...what a scumbag.
That's why some guys get beat up!
Sorry to hear that man... total BS
So bringing this back up to the top here again.
My plans have changed to include doing alot more work on the dually sooner than later.
Plan is to put the 6.2 turbo motor I have in the dually, 465 trans. Sell the 454 short block and heads and headers etc. most everything I have for the 454.
Then sell the Jimmy and all my associated blazer parts to do the suspension and do a flatbed on the dually.
While this is not my favorite plan insurance costs, overall building costs pretty much all costs are cheaper with 2 vehicles rather than 3.
It really bums me out that I have to sell the Jimmy but it just doesn't make sense to have 3 rigs that are going to nickle and dime me to death, makes much more sense to just have 2.
Putting the 6.2 turbo in the dually is certainly not ideal but will give me about the same mileage as I get out of the Jimmy, I simply cannot afford to drive a 454 gas guzzler.
Not much will happen until spring but I pretty much have the entire drivetrain that is needed and selling the 454 will allow me to get the rest of what I need.
Getting the dually running and driving has to happen before I sell the Jimmy.
So the dually will become the mild wheeler/ daily driver/ tow rig.
I realize it is a huge compromise and by huge I mean its a big truck. Little worried about trail riding with something this big.
So 2 questions for the masses, I plan on running 37" hummer tires, cause they are cheap and well they are cheap. Should I stay dually? It will never tow a super heavy load ( remember 6.2 diesel with a turbo) but I have always wanted a dually.
So keep it dually or just run the h1 rims on the dually axles?