CK5
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1970 Chevelle Malibu "400" Clone
- Thread starter 80' 427
- Start date
Like the helpers wheels! Needs pneumatic tires on it.
Was there some assembly required on the evap unit before install? Just curious as there is on the unit for a square body.
How did the firewall plate match up for existing holes used. Again the squarebody unit I had experience with some of the holes they suggested using didn’t match up to the plate they sent.
Was there some assembly required on the evap unit before install? Just curious as there is on the unit for a square body.
How did the firewall plate match up for existing holes used. Again the squarebody unit I had experience with some of the holes they suggested using didn’t match up to the plate they sent.
The evaporator was assembled. holes mostly close. the kick panel close out/hose bulkhead was too big and had 3 holes off. The evaporator bracket was a pain. You use 2) 1/4-20 x 1" studs to get it hung then tighten one and replace the other with a bolt, then remove the second stud and replace it with a bolt. I ended up using a 1' piece on top to get the hole found. Evaporator bracket to the dash is way off. Not sure what to do with it yet. Afraid to drill a new hole, my luck.it would be in the evaporator core. In dash controls required notching to fit the dash. Compressor bracket interfered with a fitting on the rear of the power steering pump so you could get the full swing to get the belt on.. I could loosen the ps bracket, get the belt on then move it past interference and tighten the brackets up. Found a bracket in the condenser bag that had no instructions, used it to brace the condenser inlet like they had me do on the outlet. Instructions are good sometimes then super vague. Says disconnect electrical connections and remove lower dash. Then later install lower dash. I found no instructions for the in dash controls yet and so far no mention of the electrical connections to the evaporator. Not the greatest system but my buddy who is the dealer had great support from them in the past.
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I HATE white face gauges.
Martin
Martin
I don't hate them, but they are not my first choice.
Well it is finished. It was a journey but, I vacuumed out the system on Sunday and charged it to 160 psi on the high side. It may need a bit more later but we will have to see. Depinned the idiot gauge connector to replace broken connector (then installed it upside down first). Finally installed the lower vents and put the gauges on the bottom of the vents. Not sure if I like how it looks but it wouldn't all fit side by side.
Just saw this, sweet car! Dig the car and the color and the engine mods!
I keep thinking "why are you building a 520 when a 505 (.100 over with a 4.25 stroke) would easily meet your goal". I guess I found a cheap crank that is nicer than I would have ever bought for a 496 build, and the rest would have been about the same with any engine I wanted to build. I hope I am not going to be disappointed but I have a car that runs 9s, I want a car I can take on "Cruise Nebraska" or maybe a slow class of Rocky Mountain Race Week, but still take my kids to ice cream, daily a couple times a week. Just have a fun car that isn't a bunch of compromises.
Sounds nice to me, although I still think if that vacuum gauge is right at idle your cam is too small for a Chevelle. 
Actually it isn't hooked up yet, but if it was reading 0 at idle, I am not sure it would run. That may suggest the cam is a bit too large.Sounds nice to me, although I still think if that vacuum gauge is right at idle your cam is too small for a Chevelle.
Ha! I meant that if it was in the blue "idle" zone, the cam was too small for a performance Chevelle.
I know you don't need my help and you like picking out stuff on your own, I get that. Although sometimes my distributors have things in stock and they don't sell to the general public, there are times I can find stuff that isn't in stock at the big mail order places.
As for the cam, I like Comp Cams for many builds, but not for a street BBC. Most of their BBC grinds are low lift relative to the duration and leave power on the table.
I know your heads aren't real good at high lift(they show flow numbers out to .650 with a max lift of .725), and your compression is relatively low, but I still think you would pick up 15-20HP with more lift at the same duration.
I'd use something more like one of these, I can check the lead time for you if you are interested...as you know cam cores are backlogged right now, but sometimes they have certain grinds sitting on the shelf. I am direct with Howards and Comp. I can also check my distributors if one catches your eye. They have a lot more options than that too. BTW, this is a Gen VI block? Your other cam said Gen VI, but I didn't go back and look what block, they have most of their grinds in Gen VI or Mark IV anyway, same grinds, different core...if its Mark IV its a different cam part number....
Howards 120406-12
235/241, 288/294, .618/.618, 112 LSA
Howards 120266-12
237/243, 290/296, .634/.640, 112 LSA
Howards 120666-12
243/249, 296/302, .640/.640, 112 LSA
Howards 121616-12
243/255, 296/308, .640/.640, 112 LSA
They offer all of those cams in both 110 and 112 LSA, the last one in 114 LSA. I would say 112 at that duration since your manual trans and gearing aren't that steep. Are you running vacuum power brakes?
I appreciate and welcome the input. Though I have built a BBC or 3, I am far from an expert and seeing as how this build has way more cubes, and the fact that I plan on running a small head and dual plane, it is hard to find similar builds to reference. It is also difficult to find any good source on how a 24 ci increase will effect cam effective rpm, idle etc. especially when using the smaller heads. Though the heads are small I have seen quite a few 650+ builds with these heads and a 496. If you use the rule of thumb that double the air flow is your realistic hp availability, these will support 670-680hp which is more than enough for a street driver. I intentionally kept the compression lower than it could be simply so when it is hot, the ac is on and the only fuel available on a long distance cruise is 87 octane. I am sure you get that.
It is a Mark iv block but I like to use the gen VI cam retainer plate to retain the cam, but I don't have too. My pistons aren't available till Jan so it isn't a huge hurry but I would like to have it running by spring.
It had manual brakes and I retained them when I went to front disks.
I will take a look at these cams and see what will work best. I know Comp is lazy on lift but I do think that helps a bit with valvetrain life. I am planning on running solid lifters on the hyd roller mostly because of all the hyd lifter problems I have seen lately. I wonder if there is a street solid that would be OK.
The final note would be with the high IE ratio (80%) of these heads, I am thinking the engine will work best with a fairly short to straight up intake and exhaust duration degrees. The only rub is right now I have a fairly small 2.5" full dual exhaust with big case dynomax turbo mufflers. I know it is hurting power but I also like how quiet it is on the highway (god I am getting old) so I may have to just look at cut outs or maybe the extra exhaust duration will help. IDK. There is a few that suggest 3" headpipes and mufflers and retain the smaller tailpipe. It is all a compromise and money is an object so I can't replace everything at once.
We will see this week if I am off on the Solid roller on a Hyd cam. My local machinist is fighting a fairly hot 496 (325 AFRs, Single plane etc) with a comp hyd with morel lifters. It rattles like a coffee grinder at idle and is peaking at 620hp at 5500. The cam is a new 4 pattern comp where the corners are a different duration than the inside. I told him I would buy the solid lifters if he wanted to try it and see if there is any change.
Are you still running a dual plane intake? Those 4 pattern cams are pretty expensive, and I think the wrong thing if you are still on a dual plane intake, which I would be with your heads and a carb(an Eddy RPM or RPM air gap). I think the 4 pattern is based on a single plane, where the inner runners are ever so slightly shorter than the outer 4 runners.
I also don't think you want a solid roller with the oval port heads with as much lift as you can get on the hydraulic rollers these days. Then you have to worry about not just the lash but the shorter lifter wheel life with the solid cam beating on it. I don't think the benefit of the solid outweighs the shorter life and increased maintenance when you aren't going to be spinning a 520 and making more power at 7K with 265 cc heads.
For example, what the gain would be with the solid vs this cam? I know you are aware you will lose .022 lift due to lash on the solid...you could say the ramp rate is faster but we can't really compare the adv duration because one is solid and the other is not, so the ADV duration is probably at .006" on the hyd and .015 or .020 on the solid. And then the lift on the solid would end up at .624" after the lash is taken up by the lobe...you would have to have both cams in the engine and measure the duration at the valve to determine which one is faster, they are that close...
Howards 120665-12 hydraulic
243/249, 296/302, .640/.640, 112 LSA
Howards 120173-12 solid
241 / 247, 273 / 279 .646 / .646, 112 LSA Lash is .022/.022 (so valve lift is .624")
For what you want to do with this ride I would stick with the hydraulic, I haven't touched the lash on my hydraulic 489 since I built it 12 years ago. And then if you want to go on a long cruise or drag week deal you won't feel like you need to take spare lifters. Like you said, you already have a 9 second ride, don't make your low 11 or 10 sec ride be just as much maintenance.
I just sent an e-mail to my Howards contact to check stock on them...
BTW, what valve springs did you get in the heads? You probably remember you need significantly more force for the solid so you don't get lifter bounce from the lash....so whatever springs you got is what you should stick with for lifters unless you plan on changing them....
I also don't think you want a solid roller with the oval port heads with as much lift as you can get on the hydraulic rollers these days. Then you have to worry about not just the lash but the shorter lifter wheel life with the solid cam beating on it. I don't think the benefit of the solid outweighs the shorter life and increased maintenance when you aren't going to be spinning a 520 and making more power at 7K with 265 cc heads.
For example, what the gain would be with the solid vs this cam? I know you are aware you will lose .022 lift due to lash on the solid...you could say the ramp rate is faster but we can't really compare the adv duration because one is solid and the other is not, so the ADV duration is probably at .006" on the hyd and .015 or .020 on the solid. And then the lift on the solid would end up at .624" after the lash is taken up by the lobe...you would have to have both cams in the engine and measure the duration at the valve to determine which one is faster, they are that close...
Howards 120665-12 hydraulic
243/249, 296/302, .640/.640, 112 LSA
Howards 120173-12 solid
241 / 247, 273 / 279 .646 / .646, 112 LSA Lash is .022/.022 (so valve lift is .624")
For what you want to do with this ride I would stick with the hydraulic, I haven't touched the lash on my hydraulic 489 since I built it 12 years ago. And then if you want to go on a long cruise or drag week deal you won't feel like you need to take spare lifters. Like you said, you already have a 9 second ride, don't make your low 11 or 10 sec ride be just as much maintenance.
I just sent an e-mail to my Howards contact to check stock on them...
BTW, what valve springs did you get in the heads? You probably remember you need significantly more force for the solid so you don't get lifter bounce from the lash....so whatever springs you got is what you should stick with for lifters unless you plan on changing them....
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