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Cody
10-15-2004, 04:27 PM
What was the HP rating for the 351's used in the 1991 prostars?

Mainly, I am looking for the most efficient ways to preserve the boat. What things are recommended to get the most out of it?

K&N filters?
Moblile one?
Synthetic oil?

Stuff like that.

Thanks and

G-man
10-15-2004, 04:41 PM
1991 Prostar should have a 240 HP engine. Changing the oil every 50 hours or at winterization is the rule. Motorcraft FL1A oil filter. In the spring replace the impeller. If you change your oil frequently, synthetic is a personal decision. Change transfluid every two years or 100 hours, same for h2o separator filter. Don't use armor-all use Formula 303 vinal formula. Wipe down your boat at the end of the day and keep a good coat of wax on it.

east tx skier
10-15-2004, 05:00 PM
If you are talking about the "most" horsepower, I'd suggest, in addition to what George has recommended, an acme 3 blade prop. Also, soak your flame arrestor in some carb cleaner (let it dry out completely before reinstalling it). Sta-bilize your fuel when you're not going to run it through there in fewer than two weeks.

east tx skier
10-18-2004, 02:21 PM
Well, you got me thinking, and I didn't want to rehijack the other thread. I spoke with Richard at skidim this morning about ways for a guy with a 351 HO and an acme prop to squeeze some more horses out of his boat. His recommendations (which corresponded with JimN's) were to upgrade to the Edelbrock performance intake manifold and to have a good machine shop bore out the cylinders a bit for better compression.

So what was, at first, just a thought is now sounding pretty good. Can anyone with an early nineties prostar who has upgraded to the Edelbrock intake tell me if I have roomunder the motor box to do this (1.5") without dropping $70 on that slim flame arrestor that they have at skidim as well? What about boring out the cylinders; how expensive a job is that?

nattylightmike
10-18-2004, 03:00 PM
I have a 90 prostar, I think that the engine covers are the same. Last winter I put on the edelbrock intake it fit fine. The only thing that I had to mess with was length of the linkage for the throttle cable. Performance wise it is hard to tell because I installed the intake, electronic ignition and rebuilt the carb all at the same time. Before I did any of this WOT was about 3900 rpm's and now it is 4600 rpm's WOT.

east tx skier
10-18-2004, 03:24 PM
Thanks for the reply, Mike. I'm not sure if the motorboxes are the same or not, but it's encouraging that you had room nonetheless. The estimation of horsepower bump that I got this morning was about 10 hp and a little more low end torque, but every little bit helps. I think I might see more gain out of boring out the cylinder chambers, but ya gotta start somewhere.

rasmithaz
10-18-2004, 04:17 PM
Hey nattylightmike....did you replace the holley with an edelbrock carb?

nattylightmike
10-18-2004, 05:08 PM
After I put the new intake on I figured an edelbrock intake/carb combo would work better. So I put on a edelbrock 600cfm that my buddy had. It worked alright but I couldn't get it dialed in for the hole shot so I put the holley back on. It took me a while of messing with the holley but I finally got the hole shot I was looking for.

Storm861triple
10-18-2004, 05:14 PM
In response to the above threads...

Boring out the cylinders to obtain more power is a terrible idea. Boring the cylinders is a SERVICE item, not a power improving item. You bore the cylinders when the wear to the bore is excessive, or when there is damage (scoring). The only (practical) way to repair this wear is to bore the cylinders to the next size that results in their being true, and installing appropriate sized pistons.

There may be a SLIGHT increase in power but we're talking maybe 5 hp...if that from the increased bore size. The cost if this is substantial (Probably at least $1000.00 unless you do all the labor your self), and it shortens the total servicable life of the engine; you are boring to the next "service" size before necessary, lessening the number of times left in the future.

If you want more power, it's a simple path. In order of bang for the buck, everyone on here should do:
Cam
Intake
Heads.

The cam will make the single biggest difference for the money(if you do it yourself), and a bigger difference than an intake ever will. You can get a new cam and lifters from Summit Racing for under $100.00! You can expect about 20+ hp from a mild cam. Easy.

The intake is the next place, at about $200.00, it's over twice the price of the cam, and it will net around 10-15 hp on an ontherwise stock motor. On a motor with the above mentioned cam, you'll see a slightly greater gain w/the manifold. The intake would come before the cam if you pay for the labor, as swapping an intake is an easy an relatively quick job.

The place offering the greatest restriction is the stock heads. This means that this is also the point of greatest total gain, stock or otherwise, if replaced. Not only will a GOOD, MODERN head increase power dramatically, it will also reduce emissions, and improve fuel economy. There is no down side or compromise to a modern head whatsoever, except for cost. Heads can be had for anywhere between $400 and $1500. depending on the head, and how you aquire them. You can get GT-40's or GT-40P's off ebay for around $400.00, loaded. Modern aluminum heads, such as Trickflow's, or AFR's run over $1000.00 brand new, but can be found in great condition used for less. Heads are going to make the biggest difference in hp and torque. On an otherwise stock engine, you could expect as much as 50 hp, but on an engine with a good cam and intake, a swap from stock heads to modern aftermarket heads could yeild as much as 100 more hp! This single component is why most of the new inboard engines make almost 100 horse more than the old 240 hp 351. (I know they're 350 Chevy's now but the reason for their power is in the HEAD! and the same goes for the Ford engine)

One last MAJOR improvement is to change the cam from a flat tappet to a roller cam, w/roller lifters. Like modern heads, a roller cam has a more modern and aggresive profile which allows the engine to make much more torque across a broader RPM range, compared to a flat tappet cam.

An AFR headed, roller cammed, 351w would have NO problem cranking out well over 350 lb-ft of torque and 350 hp, all below 5500 RPM. Check this link out, notice the second engine down. That's just a little 302. Our engines have another 1/2" of stroke putting the twist on things, and that little bugger is putting down OVER 300 lb-ft at only 2000 RPM! Think that would yank you up?...

http://www.airflowresearch.com/dyno/ford_dyno.htm

That power in an older MC would knock anyones sock off, and I would put money on it getting better fuel economy than our current stocker.

Please don't bore the cylinders unles they're worn out. :)

east tx skier
10-18-2004, 05:49 PM
Storm, thanks for the info. As for the cam, I've heard that people have had problems with getting water in the cylinders after replacing the stock cam with something geared more toward performance. I'm not an engine guy, but can you think of any reason this may have occurred. I believe I've already got GT40 heads on my boat as it's a 351 HO (285 hp).

Thanks again.

Storm861triple
10-18-2004, 06:43 PM
The GT-40 heads are good, but the P's are better. They use a more modern design for the combustion chamber, and introduce a more contorled "swirl" of the air fuel into the combustion chamber. I'm not telling you to change to them, but for any one going from the E7's to something else, for the same money as the GT-40's they P's are better.

The only thing I can think of w/regard to water in the cylinders is that a longer duration cam can allow *some* exhaust back into the cylinder at low RPM (idle). The stock cam does too, but not as much. The more radical you get in your cam selection, the more of this could occur. However, if it were me this would be the last of my concerns. There are boats out there w/WAY more radical cams than anyone on here will ever select (I certainly hope) and they don't fill their cylinders w/water. Look at some of the "California Hot Boat" and "Cigarrette" boats w/ BIG cammed, rumpity-rump engines.

Also you can get an aftermarket cam that has the SAME duration as you stocker, but faster opening and later closing ramps, and higher lift. The cam technology in our carbed engines is at least 30 years old.

JimN
10-18-2004, 06:54 PM
The problem I have seen with water in the cylinders was mostly Mercruiser when they changed their exhaust manifolds and on some boats, there wasn't much elevation difference between the waterline and the risers. This also coincided with their run-on problems on their carb'd motors. When the engine would run on, at the very end, it would rotate backward and suck water in through the exhaust valve and hydro-lock.

What do you think about shaving the heads if the stock ones are kept, as opposed to boring it?

Storm861triple
10-18-2004, 07:09 PM
Good explaination on the water ingestion.

"What do you think about shaving the heads if the stock ones are kept, as opposed to boring it?"

Who are you asking? If you're asking me, I'd say YES. I think these older engines have low compression. I thought it was around 8.5:1, but that may not be correct.

If it is, then absolutely cutting the heads would be a good bang for the buck mod, that would have virtually no draw backs or compromises. As cool as these engines run (compared to cars) I think they can easily take a good bit more compression, esspecially if you're willing to run high octane (91 or better) fuel. More torque and crisper throttle response from idle to top RPM is what you'd get from that mod. Not to mention better fuel economy too.

JimN
10-18-2004, 07:16 PM
storm86- I was asking you, by the way. I don't remember hearing that they were higher than 8.5:1 till they got into the 1990's, then added injection.

For the money (top end gasket kit and having them shaved with removal/reinstallation and maybe a valve lob since they're already off), it shouldn't cost much more than a few hundred, don't you think?

Storm861triple
10-18-2004, 07:24 PM
I think if I took the heads off and found enough seat/guide wear to warrent a valve job, that would motivate me to just start shopping for new/used better heads. That'd be all the motivation I'd need! lol.

BUT I agree that if they were in good shape, I would think you could do a top end gasket set for about $150.00, and I have to say, if I had the heads off (and therefore the intake, rockers and push rods etc), I'd have to throw another $82.95 into a cam and lifter set. Being that far into the engine, I'd just HAVE to do it! :)

So yeah, for less than $500.00, you could easily make a very noticable improvement, IMO.

-Tom

Thrall
10-19-2004, 10:17 AM
If the PCM 351Ws are the same long block as the late 80's/early 90's Ford Pickup motors, then I believe you guys are correct w/ the 8.5:1 comp ratio. It certainly wouldn't make the engine any more finicky to go up to 9.5:1.
What does the P stand for in GT-40P heads? Is that just a port and polished GT-40 head? And if so, if you're getting the heads cut and rebuilt already, a porting job would wake it up a little. Although you may be getting into the $ range of just shopping for higher perf heads.

east tx skier
10-19-2004, 10:37 AM
So what's involved in having the heads shaved? Hypothetically, would I look for a good machine/engine rebuilding shop to have this done (did I say hypothetically).

Storm861triple
10-19-2004, 12:43 PM
Thrall, the GT-40 and the GT-40P heads are not the same casting. Therefore, the P isn't just a "ported GT-40" head. The P features a modern port design that maintains a high velocity which helps low end torque, while still maintaining great flow characteristics. The port design also induces "swirl" to the incoming air/fuel mixture, much like the GM Vortec head does. Further more, the combustion chamber is a "modern design" as well that promotes swirl, and "fast burn" combustion, and has a more centrally located spark plug. The P also features more flow on the exhaust side than the standard 40.

The P head BTW, were designed for and can be found on the V-8 Ford Explorer. This head allowed Ford to obtain the desired power and still meet emission requirements into the late 90's.

Also, if you get into paying someone to port your heads, it becomes cheaper to buy a better set of heads. If you do the port work yourself, that is another story.

East TX, to cut the heads, simply remove them, take them to a machine shop, and tell them how many thousands you want taken off. Determining that is the hard part. You need to dertermine how many CC's your current combustion chamber is, and where you need to be to get the desired compression (I agree w/Thrall that ~9.5 would be good) and then figure how many thousands removed would achieve the desired combustion chamber size. You can find all this info on online calculators. Once you have figured it out, you can tell the machine shop how much you want cut, and it should cost about $50.00 per head or less.

-Thomas Kendrick

Storm861triple
10-19-2004, 12:54 PM
All you ever wanted to know about the GT-40P head. Better get comfortable...

http://www.corral.net/forums/showthread.php?t=159577&highlight=gt40p

JimN
10-19-2004, 02:40 PM
Doug- some machine shops (especially automotive specific) will be able to tell you how much needs to come off for a certain amount of compression gain. The rule of thumb I have heard is that the compression won't increase appreciably unless more than .007" is shaved. When a motor is overheated, especially repeatedly, the heads tend to warp and the seal to the block suffers and often fails. The warpage is removed by shaving the heads which flattens the mating surface. This works as long as the heads haven't warped excessively. When I needed machining done for the last dealership, there was a NAPA store w/ machine shop nearby and they were knowledgable AND good at it. Ask around your area and talk to people, especially gearheads, to see where they have machining done.

east tx skier
10-19-2004, 02:51 PM
Thanks again, everyone, for all the info.

east tx skier
11-17-2004, 12:05 PM
Okay, I've got my new intake manifold. Spoke to a mechanic, who is going to install for me. Also going to get the cylinder heads shaved (and a valve job while they're at it) as mentioned above to get 9.5:1 compression. I will need a new head gasket kit. Does anyone know if this is marine specific. Skidim seems to want about $176. Would I save money by looking elsewhere?

What kind of increase in HP could I expect from the higher compression ratio?

Ric
11-17-2004, 12:22 PM
Doug I'm certainly no expert but I would think that depending on the age or wear on your motor, you may be adding stress to the lower end by machining the heads and reseating the valves for increased compression. ??????? It's at least worth asking about before you do it.

JimN
11-17-2004, 01:04 PM
I doubt that the increase will be sufficient to worry about the lower end. Since the heads are coming off anyway, that would be a good time to look at the cylinder walls for their condition. If they're scored or are totally smooth, the bearings may be somewhat worn. If they still have the cross-hatching with minimal wear, the bearings should be OK.

$176 for an upper end gasket set is way high. Go to NAPA or other good auto parts store and get the price for a Fel Pro marine set. I just called a place here in MKE and got a price of $112 plus shipping. It is marine specific. Never heard exactly what the differences are, but I assume it has to do with raw water and the amount of water or coolant getting to the intake manifold, since I had seen istructions in the gasket set on a Jasper motor stating that if it was for marine, do this- if it's for a car/truck, do something different with the intake gasket.

Are you going to replace the cam, too?

east tx skier
11-17-2004, 02:35 PM
Thanks for the info.

"lower end"? Can you be more specific. The motor has fewer than 600 hours on it.

As for the cam, I've pretty much decided against it for now. I've heard both good and bad about it as far as problems with water getting into the cylinders. My dealer suggested that as an option this morning and said it shouldn't be a problem as long as it was a marine cam and had the proper rotation. Since I'm not doing the work myself, I'm concerned with the installation expense for a new cam (I know the parts are pretty cheap.

JimN
11-17-2004, 04:51 PM
Lower end is just the wrist pins on the pistons, crank bearings and main bearings. Like I said, if the oil has been changed frequently and it hasn't been overheated excessively, it should be fine. It's not as if you're thinking af adding a blower. Right?

You're not gonna turn it into a drag boat, are you? (6balls- this isn't what you think it is) :D

east tx skier
11-17-2004, 05:19 PM
No overheats to speak of. Never gotten over 160 running while in my care. Oil changed regularly. Looked into marine cams. Pretty pricey (around $300 and some change). It's already got a blower on it ;). But that'd be cool to reconnect that rocker switch, eh.

The intake and the shaving will probably be the extent of my torque/hole shot seeking mods. I've got two other family members with 300+ HP boats and a newly installed slalom course with a pretty short setup. Just having some fun with it all. I wonder how big of a nitrous tank I could fit in the floor locker? :D

JimN
11-17-2004, 05:32 PM
"I wonder how big of a nitrous tank I could fit in the floor locker? "

Big enough for you to try to climb trees with it. If you can keep it from cavitating.

east tx skier
11-18-2004, 10:18 AM
Hey, you know me. I'd just say it was the acme 3 blade prop. ;)

Storm861triple
11-19-2004, 01:09 PM
I agree with Jimn on the gasket set. You can do WAY better price wise. Also check www.Summitracing.com, Jegs and PAW.

Also on that cam. $300.00?!! That's insane! Who was trying to rob that price on a flat tappet cam?? For that price you should be getting a nice billet roller cam (which you don't have).

Summit has great cam and lifter kits that will work beautifully in your boat for less than $100.00 bucks for the whole kit. PLEASE don't spend 3 bills on a flat tappet cam!

As for your "bottom end holding up", this is a tired out topic that is repeatedly brought up on various forums (not just this one) by people who have little to zero experience modifiying engines. It's like an urban ledgend or an old wives tale that just won't die. Here's where it comes from:
Joe Billy-Bob has a beater '78 Camaro, with 150,000 poorly maintained miles. He tosses (insert parts here) onto his motor and it runs great for a week, then it starts(insert bottom end issue here -oil buring, spun rod bearing etc). The problem wasn't caused DIRECTLY by the new parts, it was caused by pushing an already EXTREMELY MARGINAL short block past it's already defined (by it's history) limits; it would have had the same issue shortly after anyway, had the modification not occured!

A well maintianed, high mile/hour short block will have absolutely NO more issue with new/mod parts than a freshly broken-in short block, and I can back that up with actual (my own) expirience with multiple high mile examples.

Imagine this scenario for a moment; you have a '01 Nautique (sorry but works for this example) with the PCM 351 HO "cobra motor". I believe it's rated at 320 hp at around 5500 RPM. This is the SAME short block (minus the cam) as the 'ol 240 hp 351 that's been in ski boats for decades! Just spiced up w/a roller cam, GT-40 heads, and EFI. Follow this? Now, let's say we buy this brand new 351 HO and run it at no more than 4400 RPM and 3/4 throttle for 5 years and 500 hours, following the recommended PM the whole time. THEN, at 500 hrs, we "open 'er up" to WOT, 5500 RPM and start enjoying all 320 hp from then on. Is it going to start buring oil? Is it going to spin a bearing? Is it going to have ANY bottom end problems? No it won't.

And is that is any different than taking the 240 horse 351, maintaining it, and then at 500 hours, slapping cam, heads and intake on it? No, it is not. All you're doing is letting more air and fuel in; the 240hp needs parts to accomplish this due to the terrible flowing originals, the HO just requires that you open the large throttle plate more! If it was built with the proper parts for a given power/RPM level and well maintained, it will pretty much always be able to deliver up to that output level, reliably.

Sorry for the rant, but that whole thought process really gets my goat. My "professor" in auto tech school used to always preach that crap: "Throw a cam in it at 150,000 miles, and you'll blow the bottom end right out of it", he'd say all the time. Der. That always used to bug the heck out of me. I guess it still does! :D

-Tom

G-man
11-19-2004, 01:37 PM
Doug with all your projects on the engine and tieing down the boat to the trailer when are you going to have time to polish all the under gear and make that boat a trailer beauty? The things we do to make summer come quicker.

Brn85ss
11-19-2004, 01:39 PM
I like the pic. of nattylightmike's engine very clean. I need new pulleys for my 351,mine are rusted and pitted so they chew up the belts.My question is are aluminum pullys really worth 5 horses,or is that a marketing pitch?thanks

Storm861triple
11-19-2004, 02:35 PM
Underdrive pullies are worth some power, whether they are made of steel or aluminum.

Realistically though, they aren't going to give you much, esspecially in a boat where you have so few accessories in the first place (just a water pump and the alt.). The alterator takes virtually no power when the pbattery is fully charged, but the water pump depending on the design of the impeller, can use as much as 15 hp. Notice I said "as much as". This would be the with the worst impeller design, and at a high RPM, like 6000+.

IMO, a better way to lessen parasitic loss and increase power, would be to replace the water pump with a more efficient deisign, and a light weight aluminum housing, such a a Stewart water pump. They claim 3hp @ 4500 RPM, while at the same time, pumping more GPH of water than the stock Ford or Chevy water pump....
http://www.stewartcomponents.net/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=HiFlowWaterPumps

As for the "rotating mass" factor of the aluminum pullies vs steel, no, that will gain you nothing that you would EVER feel or notice. Money wasted.

east tx skier
11-19-2004, 02:48 PM
Thomas, the cams I saw at that price were marine specific. I was reading about the differences yesterday, but wouldn't be able to regurgitate them at the moment. I have no intention of buying one at that price. Since I'm not installing it myself, I was left with the impression from this thread that I might get some good bang for the buck by having the heads shaved a bit in addition to the new intake manifold.

From there, I'll probably leave it alone and start polishing my underwater gear like George suggests. ;) My goal is to get it into the 300s, take it out, and enjoy it.

Storm861triple
11-19-2004, 03:11 PM
Whew! I'm glad you're not going for that cam. :)

BTW, you don't need a marine cam. An automotive cam would work just great.

As for your goal, I hate to sound negative, but there's no way you're going to see 300 hp with stock heads and cam. You need a cam if you want 300+ hp.

Once you have the heads off, the cam isn't much more work; front timing cover assy, timing chain and gears, lifters, and out comes the cam.

east tx skier
11-19-2004, 03:19 PM
New intake manifold and shaving GT40 heads won't yield 15 hp?

Storm861triple
11-19-2004, 03:40 PM
Whoops! I forgot that you have the 285 hp version. Sorry. Yes, I suspect an intake and head milling will get you there. Not much over that though. The head milling isn't really going to increase peak hp much...maybe 5 hp at the most. What the head milling does is increase low to midrange torque, and throttle response dramtically. The engine would feel much more "punchy" with just an increase in compression. It will help your hole shot.

The majority of your hp gains, by far, are going to come from the intake though, and that will just barely squeak you to about 300 hp, IMO.

east tx skier
11-19-2004, 03:50 PM
And when I say horsepower, I suppose I'm really as interested in good low to mid-range torque. I don't barefoot and won't be operating the boat much passed 36 mph (usually slower). If there is any practical reason for this cash outlay, it'd be that we've got a slalom course with a pretty short setup.

Am I right that replacing the cam would be a more expensive route when I'm having someone else do the labor? Right now, milling the heads with a valve job is going to run me $200. Add a gasket kit to that and the labor to get the heads out of there. Would a used set of GT40p's be a more cost-effective way to do this or should I just forget about everything and just put the new intake on there. I don't mind just doing that if my gains apart from the intake will be minimal.

My thoughts are that the engine's going to be somewhat apart to put the new intake on. What's the least expensive thing I can have them do as long as I'm already paying for some labor.

What will the performance camshaft give me? What will the drawbacks be? I recall having the cam replaced in my Jeep and it was pricey labor-wise. If it's my best bet, which one should I get and do I need to watch any increase in dwell to keep the water out of the heads at idle.

I know it sounds like we're going over the same old ground here, but it's not like too many people are hitting the water today.

English major wants to learn. :confused:

Ric
11-19-2004, 03:59 PM
I agree with Jimn on the gasket set. You can do WAY better price wise. Also check www.Summitracing.com, Jegs and PAW.

Also on that cam. $300.00?!! That's insane! Who was trying to rob that price on a flat tappet cam?? For that price you should be getting a nice billet roller cam (which you don't have).

Summit has great cam and lifter kits that will work beautifully in your boat for less than $100.00 bucks for the whole kit. PLEASE don't spend 3 bills on a flat tappet cam!

As for your "bottom end holding up", this is a tired out topic that is repeatedly brought up on various forums (not just this one) by people who have little to zero experience modifiying engines. It's like an urban ledgend or an old wives tale that just won't die. Here's where it comes from:
Joe Billy-Bob has a beater '78 Camaro, with 150,000 poorly maintained miles. He tosses (insert parts here) onto his motor and it runs great for a week, then it starts(insert bottom end issue here -oil buring, spun rod bearing etc). The problem wasn't caused DIRECTLY by the new parts, it was caused by pushing an already EXTREMELY MARGINAL short block past it's already defined (by it's history) limits; it would have had the same issue shortly after anyway, had the modification not occured!

A well maintianed, high mile/hour short block will have absolutely NO more issue with new/mod parts than a freshly broken-in short block, and I can back that up with actual (my own) expirience with multiple high mile examples.

Imagine this scenario for a moment; you have a '01 Nautique (sorry but works for this example) with the PCM 351 HO "cobra motor". I believe it's rated at 320 hp at around 5500 RPM. This is the SAME short block (minus the cam) as the 'ol 240 hp 351 that's been in ski boats for decades! Just spiced up w/a roller cam, GT-40 heads, and EFI. Follow this? Now, let's say we buy this brand new 351 HO and run it at no more than 4400 RPM and 3/4 throttle for 5 years and 500 hours, following the recommended PM the whole time. THEN, at 500 hrs, we "open 'er up" to WOT, 5500 RPM and start enjoying all 320 hp from then on. Is it going to start buring oil? Is it going to spin a bearing? Is it going to have ANY bottom end problems? No it won't.

And is that is any different than taking the 240 horse 351, maintaining it, and then at 500 hours, slapping cam, heads and intake on it? No, it is not. All you're doing is letting more air and fuel in; the 240hp needs parts to accomplish this due to the terrible flowing originals, the HO just requires that you open the large throttle plate more! If it was built with the proper parts for a given power/RPM level and well maintained, it will pretty much always be able to deliver up to that output level, reliably.

Sorry for the rant, but that whole thought process really gets my goat. My "professor" in auto tech school used to always preach that crap: "Throw a cam in it at 150,000 miles, and you'll blow the bottom end right out of it", he'd say all the time. Der. That always used to bug the heck out of me. I guess it still does! :D

-Tom

Well, there you have it.

east tx skier
11-19-2004, 04:12 PM
Not yet I don't. ;)

Storm861triple
11-19-2004, 05:16 PM
Let's see here...

I didn't know before your last post that you're paying for labor; I ***-umed that you were doing the intake and heads yourself and possibly paying to have the cam done. Maybe I didn't read well enough. :)

So like I said, the compression won't give you much increase in peak hp (top speed). But it WILL help acceleration and midrange torque, so for getting up to speed quickly, that is a good mod to do. Now, is it good bang for the buck seeing that you're paying for labor? I'm on the fence about that one. I guess it all depends on how much money you have. You will FEEL the difference from the increased compression when you take off from a stop. The intake would be noticable too...

I'm just babbeling here. I need to break this down. IMO:

Intake-$200.00
Labor- 2 hours, $150.00
Total- $350.00
Gains- Mid to upper RPM increase. Slight increase in top end speed.

Heads in addition to intake.
Machine work -$200.00
Gaskets -$100.00
Labor to R&R heads -$2 hours, $150.00
Total -$450.00
Gains -Increased torque across the RPM range, but most noticable in teh low to mid range, with an increase in throttle response and better fuel economy. Peak hp my be up by 5 or so.

Cam and lifter kit -<$160.00
Gasket set -$40.00
Timing chain -$40.00
Labor* -4 hours, $300.00
Total -$540.00
*beyond intake and heads.
Increased power and torque from about 2000 RPM on up. Big increase in PEAK torque (thoughthat peak will occur at a slightly higher RPM) and peak horse power.

Another option;
1.7 ratio Roller Rockers -$200.00
Labor* -$0.00
Total -$200.00
*beyond Head R&R (it's part of that job).
Increased torque and power across the same RPM range as with the stock cam.

Storm861triple
11-19-2004, 05:21 PM
I guess that if you're paying for labor, the cam might not be a great value.

Definitely intake and 1.7 rockers, and the heads probably too. A cam would make the biggest difference of all those parts, but it will cost you the most too apparently, with labor. Does this help at all? Or did I just make it more confusing? :D

east tx skier
11-19-2004, 05:27 PM
No, that helps. Looks like I'm sticking with my plan. I'll save the camshaft upgrade for when I win the lottery. Already have the intake in my grubby little hands. 'Til Spring, save, save, save.