I took the initiative to have my fiero heads cc'ed so that I could calculate the actual compression ratios. I also measured the deck height before I zero decked and squared my 3.4-liter block.

My heads measured from 49.4-51.5 cc’s with the SI valves installed. I was not surprised that the combustion chambers varied so much in volume because the molds that GM uses to make these heads are sand molds that wear out and these are cheap production heads. The heads did not get a valve job yet.

The deck height varied quit considerably from .007-.025" and are no were near being square to the main. I averaged out the deck height to .016" (.007+.025 /2= .016) when I calculated the compression ratios. The heads are not a true 60-degree angle either because of the varying deck heights. I guess this is typical of GM products since there manufacturing tolerances are very poor and they outsource many of their parts. I had my block zero decked and squared to help eliminate detonation and give me the highest compression ratio possible.

If you have the 3.1-liter engine with a 3.310 stroke and a 3.520 bore (3.5 with a .020 overbore) that with the above combustion chambers and the Silvolite 1486 pistons your actual compression ratios are,

Stock deck with a .016" average deck height from the top of the piston 8.2 with a 51.5 chamber volume and 8.41 with a 49.4 chamber volume.

With a zero deck height the compression ratio is 8.46 with a 51.5 chamber volume and 8.69 with a 49.4 chamber volume.

If you have the 3.4-liter Camaro engine with a 3.640 (3.620 + .020 overbore) bore and a 3.310 stroke like I do with the Federal Mogul H562CP DOHC pistons than the compression ratios are,

Stock deck height with a .016" average deck height from the top of the piston 9.24 with a 51.5 chamber volume and 9.5 with a 49.4 chamber volume.

With a zero deck height the compression ratio is 9.58 with a 51.5 chamber volume and 9.86 with a 49.4 chamber volume.

Hope this data finally clarifies the confusion that has been going on here about actual compression ratios with the 3.1 and 3.4-liter engines. The part that surprised me was that the Silvolite pistons do not give you the claimed 8.8-1 compression ratio everyone says they do. The claim that the Federal Mogul H562CP DOHC (Double Over Head Camshaft) pistons used in the OHV 3.4-liter motor give you a 9.7-1 compression ratio though is relatively correct.

I forgot to mention that the Silvolite 1486 pistons have a dish that measures 12 cc's. The Federal Mogul H562CP pistons with the four valve reliefs measure 7 cc's.

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[This message has been edited by 88formula (edited 02-04-2001).]

Thanks for doing the leg work that no one else seemed to want to do.
Now, a new question:
What about if you used the DOHC pistons in an aluminum head motor?

good post good info
when checking cc in heads did you use glass plate to get true volume or just level and fill up if last minucus [surface tennision] can vary 5%or more. gasket thickness inc in calculation?

That's some really bad news, 88. I guess that explains why my motor doesn't have any top end at all. I guess the best solution would be to get a 3.4 block, some of those pistons you have, and drop my crank/rods in there. That setup should make some good power considering I already have the cam and heads. Have you run the computer dyno for your latest findings? What kind of gains could I expect if I did what I'm talking about? BTW, thanks for finding that out for us.

So.... With my 3.2 and the Federal Mogul pistons, I'll have a compression ratio of 8.2-1 without shaving the heads?

My heads are shaved a tiny bit, probably not enough to make a difference.

Eric, you said "My heads are shaved a tiny bit, probably not enough to make a difference." Well what is a tiny bit to you?

I knew I was going to get a bombardment of questions here about this with some doubting my findings so here are the answers to your questions.

Cooter, I don’t know what the volume of the chambers are of the aluminum heads because I did not have those heads cc,ed. I cc’ed the fiero cast iron heads. If you could get me the volume of the combustion chambers on the aluminum heads I could calculate the compression ratio for you. I would suspect that because the aluminum heads have a smaller head chamber volume than the cast iron heads that the resulting compression ratio with the DOHC pistons would be very high.

Ray b, I used a piece of Plexiglas with a hole drilled into it to let the water and alcohol mixture into the chamber. I sealed the glass to the heads with grease tightly and also sealed the valves to their seats with grease. I used a laboratory vile that measures liquid volume down to 1/10 of a cc, 50cc for each vile. I filled the chamber completely with the liquid and noted how much liquid left the vile. The setup I used is actually owned by my friend and machinist who also owns an engine dynamometer and builds 30-plus thousand dollar engines. I did take into account the head gasket volume, which measures 7.28 cc. I used the compression ratio calculator in the Dyno2000 program to calculate the compression ratios. It’s quicker and less apt to let a mistake go through. I gave this program to my machinist and he loves it just for the compression ratio calculator because it saves so much time over doing it mathematically.

Eric, It’s actually good news for you because you now know have a better idea of what the compression ratio for your engine is. You don’t have to go through the trouble of getting another block. You can have custom lightweight pistons made up for your engine and have the block zero decked and squared like I did. Then you can keep your engine, which with 30,000 miles is still fresh. I’m expecting 210 horsepower @ 5500 rpm and 238-ft. lbs. of torque @ 4000 rpm for my 3.4-liter engine with 9.78 compression and FOCOA headers. I need allot of information about your engine to give you an accurate engine simulation but off the top of my head you can expect 181 horsepower and 210-ft. lbs. of torque with the GM performance 12363220 camshaft, ported heads, 9.8 compression, and ported exhaust manifolds. That is for your 3.2-liter engine. The Federal Mogul H562CP pistons are of low quality and I had to do some things to them to make them exceptable for use in my engine. They are also relatively heavy at 513 grams. They are the only pistons that I could find for the 3.4-liter engine that will give me a higher compression ratio than the stock junky cast aluminum 9.0-1 pistons. To get the custom pistons I really want would cost me about $800-$1000. You can get the H562CP pistons for about $180-190 and they are hypereutectic pistons. I don’t remember what the rings cost.

GT Bastard, you poor bastard (jk). You will have somewhere around 8.2-8.5 compression if your deck height is the same as mine and you have the SI valves and your head gasket is .042” thick. The stock valves look like they have a little more volume than the SI valves because of their big tulip, which I guess will lower your compression ratio even more. I would recommend that you not mill your heads any more than you have too. It is better to zero deck your block and square it at the same time. This means that the distance between the top of your piston and the deck is 0 and the deck surface is parallel to you main bores. Your deck surfaces will also be a true 60-degree angle from each other too. I am only milling my heads about .008” or less. I don’t want any problems with the intake manifolds not fitting properly. To really gain any compression by milling the heads you have to angle mill the heads. Once you do that though you will probably have to mill the intake manifolds to make them fit properly and your valve train geometry will be way off.

Steve, his compression ratio probably went up one tenth of a point or less.

------------------

88, I don't really see any good news about having to put in new custom made pistons. As far I I know the slugs don't exist, but I could be wrong. I don't want to pay $800 for a set either. The cost of my original 3.4 block plan would be far less than that, plus I'd get more power in the end.

I'm milling my heads .20 over with SI valves... So I should be slightly higher than 8.5-1... That's fine with me. Even raising the compression a full point isn't a huge gain. 4% increase if I recall correctly. Eric, I don't see how that kind of increase is worth tearing your motor apart.

But it runs like piss down my leg on a cold winter's day.

88formula you the man ok so what if .060 over on a 3.4 or 3.1 c/r up much then?
but realy need flat top piston wonder if enuff to do limited run of 100 or so 144? to get better price for gang here.
any other motors with 3.5 or 3.6 pistons with flat tops?that could be made to fit?

[This message has been edited by ray b (edited 02-06-2001).]

Ok I have the Federal mogul pistons. The H562CP. There are no valve reliefs in these pistons. It is a dish. I still have the box and the part number on the box. Again it is a dish and no valve reliefs.

I have my heads shaved .006 to true them up. the block was shaved to true it up but not to zero deck it. So maybe take a few thousandths off the original numbers.

No my block was bored .030 over and I got the pistons of .030 over. It was blueprinted to make sure that it was at a true 60 degree angle to the crank centerline. If the dish of these pistons is 7cc and the gasket thickness is 7.xx like you said, then what is the compression ratio on this 3.2 liter then? I have the SI valves as well. Oh yea this is a 2.9/3.1 block and not a 3.4 block.

You gave the compression ratio for a 3.4 but not a 3.2. I am guessing though they would be the same? Either way I was positive that the Fed mogul pistons give would be around 9:1.

Eric, I though you said you bought the Federal mogul pistons? Or did you actually buy the silvolite pistons?

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Shaun 85 GT with nitrous
0-60 in 5.6 seconds
Preferred Performance

No, they're Federal Moguls just like you have. I don't have the SI valves though because I cheaped out.

Okay Shaun, assuming what I is enough to work with, is there any magic you, or anyone else you know (like Travis and his buddies), could do with a chip? I've got some stock 5.0 19lb injectors just lying here in my garage, plus I already have an adjustable fuel reg. on the rail. I plan on going to a dyno this spring once I put on a new cat back exhaust without the cat.

Eric if you have the fed mog pistons then you should have a higher compression ratio then what you think. I beleive you are around 9:1. like what was quoted for the 3.4

i will get back to you oin the chip thing. I gotta jet right now. look tomorrow for a follow up post. Later Man

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Shaun 85 GT with nitrous
0-60 in 5.6 seconds
Preferred Performance

If anybody is interested in knowing this. The dish in the Firebird/Camero 3.1 liter engine is 10.64cc. I got that off the blue print for GM pistons 10070145 (std.), 10100065 (.5mm OS) and 10100066 (1.0mm OS).

Alright, I now have the cam specs. The GM cam part number is 12364059. Duration @ 0.050 is 204 degrees intake and 216 degrees exhaust. Gross lift is .427 intake and .454 exhaust. Lobe centerline is 112. This cam is different than the one 88 described above. His cam, part number 12363220, is milder even though it has the same gross lift numbers.

I know I got the web address( http://www.geocities.com/calgaryfieros/3400engine.htm ) from someone here. The thing that keeps bugging me is that this person has a differnt Federal Mogul piston part number for the 3.4 dohc. So could someone tell me if we are talking about the spec for h562cp or the other number. I am a little confused right now.

I originally followed the information at this site
http://www.angelfire.com/on/freddysplace/shortblock/shortblk.html

[This message has been edited by fierosound (edited 02-07-2001).]

Eric now that I have your camshaft specifications I can give you a better prediction of what kind of power you are making and tell you why your motor has less top end power. The GM 12364059 camshaft has 204/ 216 duration and .427/ .454 lift intake and exhaust. The GM 12363220 camshaft has the same 204/ 216 duration and .427/ .454 lift but the GM 12364059 favors the lower end of the rpm band while the GM 12363220 is more of a balanced compromise or more mid-ranged. The performance of a camshaft depends on the stroke of the engine. A mild camshaft used in a long stroke engine might be a performance cam when used in a short stroke engine. Here are the numbers I got from Dyno2000.
GM 12364059
RPM Horsepower Torque
2000 68 178
2500 89 186
3000 112 196
3500 131 196
4000 145 190
4500 152 178
5000 151 158
5500 141 134
6000 123 107
6500 100 81

GM 12363220
RPM Horsepower Torque
2000 66 174
2500 86 180
3000 109 191
3500 128 192
4000 144 188
4500 152 177
5000 157 165
5500 154 147
6000 143 125
6500 126 101
This is with stock heads, ported exhaust manifolds and a performance exhaust system, 8.2-1 compression, and a 3.520 bore 3.310 stroke. Now if your camshaft timing is advanced three degrees because you did not degree your camshaft timing than you will have even less top end power. The numbers will look like this.

GM 12364059 with three degrees of cam timing advance.
RPM Horsepower Torque
2000 68 179
2500 90 189
3000 113 197
3500 131 196
4000 144 189
4500 149 173
5000 144 151
5500 131 125
6000 111 97
6500 86 70

Now add a restrictive exhaust system (plugged cat or bent pipe) and wrong air fuel ratios and you have a very poor performing engine.

I used Dragstrip2000 to get a ballpark performance figure with that engine and a 2925-lb. vehicle weight including you and the five-speed transmission. I got 0-60 mph in 7.5 seconds and the quarter mile in 15.5 seconds @ 87.2 mph with the first engine dyno I gave you (GM 12364059). With your cam timing advanced your car will go 0-60 mph in 7.8 seconds and do the quarter mile in 15.7 seconds @ 85.7 mph.

Let me know if this information helps you Eric.

GT Bastard you are right. Raising the compression a full point on my motor raises my peak horsepower 5.3% and my peak torque 4.3% and raises the output THROUGHOUT THE WHOLE RPM BAND an average of 4%. The higher your compression ratio is the better your fuel mileage will be too.

Ray b, boring the motor from .060” instead of .020 will raise the compression ratio on a 3.4 liter motor two tenths of a point or from 9.0-9.2. On a 3.1 in will raise it almost the same. That is with a 0-deck height. With The piston down .016 from the deck it will be a little less for both.

Shaun41178, I have the exact same pistons you see in the picture below that Fierosound has provided for us except that the number is different. I THINK MY PART NUMBER MAY BE WRONG. I don’t have the pistons with me right now because they are at the machine shop. I’ll check that later. The head volumes can differ from head to head for the same style heads as they did on mine. There is a guy here that claims he had his combustion chambers cc’ed @ 52 cc. But with 28cc combustion chambers and the 1486 pistons in a 3.1-liter engine the compression ratio would be a sky high 11.59-1. Your saying that the combustion chambers on the aluminum heads are almost half the size of the iron heads. The numbers I posted here on compression ratios are COLD HARD FACTS. There not just guesses. The DOHC Federal Mogul pistons used in the 3.4-liter engine will not fit in Eric’s 3.1-liter engine.

Steven, the Dish on the Silvolite 1486 pistons is 12 cc according to the Silvolite web site http://www.kb-silvolite.com/slvpg79.htm.

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[This message has been edited by 88formula (edited 02-06-2001).]

The Gm -059 cam is designed specifically for high rpm torque and hp according to GM. Its in the performance parts catalog and actually comes in the 3.4 iron head crate engine. It says it is a upgraded cam for a 2.8 engine and is designed for mid and upper range power.

Yes the Aluminum head engines of the Gen 2 design have 28cc displacement according to the books I have read. More specifically, "How To Rebuild your GM 60 degree V6"

Why wouldn't the DOHC pistons that some have used in their 3.4's not be able to be used on a 3.1/3.2 engine? To me that makes no sense. The only way I can see them not fitting is if The 2.8/3.1 block can not be overbored large enough to accept a stock sized DOHC piston or overbored DOHC piston. I don't have the bore numbers handy but is this the case?

The Federal mogul H562CP is the piston for a 3.1 iron head engine. It is not the DOHC piston. The DOHC piston is Fedreal Mogul part number is H684CP. It is said that this is similar to the silvolite 3409 piston. However the valve reliefs might be different altering compression.

It would be my guess that the Federal mogul pistons with the dish have a dish of about 10-12 cc's. According to the KB Silvolite page the 1486 have a head volume of 12 cc. Meaning the piston has a dish of 12 cc as we know the head volume is approx 50-52cc. It also states that they give a 8.8-1 compression ratio. But yes they could be wrong. Please read on to see why I don't think they are. Cross Reference the KB 1486 piston to the Gm piston part number 10070115-B or number 10118601

Cross Reference KB 3420 with Gm part number 10146832. Find the dish on the GM piston and then the dish on the KB piston. Well the dish on the KB 1486 piston is 12c according to them. The dish on the KB 3420 is going to be about the same as well. Why because accoding to the website the piston offset and compression height between the two pistons is nearly identical. So lets say GM's has a dish of 10 and the dish of the KB is 12. That is only an additional 12cc for the whole engine. But the overbore should offset that and bring the compression back to where it was which is about 8.9:1 like from the factory, It does say the head recess on the 3.1 is .106 deep and on the 3.4 it is .080 deep. Maybe that means something too.

Now the reason I don't think that the compression ratio for any of these pistons can be around 8:1 is this. Piston manufactureres do not mkae pistons with a higher compression as what comes from the factory. Why you might ask? Because the piston manufacturers believe that when you go to do a rebuild you are going to have the heads shaved and the block decked. This increases compression ratio. Now if they did make pistons to give the same compression on a rebuild then when the engine is rebuilt and the ehads are shaved and block decked the compression ratio will be over stock which could cause pinging if the right gas is not used and could destroy the pistons.

Now perhaps the problem lies with GM. Perhaps they misquoted and the actual initial compression ratio is 8.5:1 instead of 8.9:1. Then a compression ratio of 8.2:1 is possible then with aftermarket pistons.

However I am going to go out on a limb and say that sluggish performance is not being caused by low compression ratios. I am going to say it is to cam timing, engine assembly techniques and prom tuning and things of that nature. i know many people here have never put an engine togethor before and then try to do this one by reading books about V8's or not reading books at all. During assembly tolerances mght not have been checked and things aren't going right. Travis threw his 2.8 on a dyno and was able to extract 150 with some tuning to it. If you guys are putting 3.4's in with bigger cams and headers and such and then still running 15's and getting beat by 2.8's then you have some tuning to do. Go to a dyno and they can help you figure out why you arent running to the best it can.

Eric you ever do a compression check and see what you are getting?

Perhaps all this can be avoided if from now on when people do the 3.1 conversion to automatically have the block zero decked. Then the compression ratio can't be a factor.

Travis looking for that excel file brother. I hope you see this post.

I might be off the mark with this one but here it goes...

With the dished pistions why not shave a little off the top, there by making the dish volume less. Then 0-deck the block to compensate for the material taken off the pistions. Id would have to look at the pistons, but as long as you didnt get to close to the rings it might work.

Holy crap! This is what happen's when I go away? I really don't know where to start. 88, I looked at your dyno results for my engine, and I have to say they look about right. I don't know if it's for the reasons you state though. I had my long block built up by the machinist who did all my engine work. This man has worked on a number of 60 degree V6s, and when I went to his shop, he had a GM V6 manual about two inches thick sitting on his work bench. I could only assume that when he degreed my camshaft it check out okay just like he said. Oh yeah, he had the cam specs too. Now that being said, my car performs like your dyno/ dragstip 2000 predicts. It's probably about 150 lbs heavier than you entered into the computer, but the rest seems right on. I don't get the part about the "lesser" cam performing better at high rpm than the cam I have. Why would GM label that cam as the big boy when it doesn't even come close to their truck/ pulling cam that goes into the S-10 crate motor? Could you explain this because it's hard to believe the longer stroke could be that much of a factor.

Shaun, I'll do a compression check ASAP.

Anyway, I really appreciate you guys going to the trouble of helping me come up with answers. This car has been bugging me for over a year now, and I need every bit of encouragement I can get to keep me plugging away at the problem.

Eric,
Maybe GM was comparing torque not HP. In a truck, you want towing ability not acceleration. If an engine produces more torque than another all things being equal except for the cam, then I would assume it would sacrifice some top end HP.

OK round three and my fingers are getting carpal tonal syndrome.

Shaun41178 about the GM 12364059 camshaft, In the GM performance parts catalog GM states that this camshaft “is designed to significantly improve mid-range torque and horsepower without sacrificing idle quality. The basic rpm range is 1500-4500 rpm”. The GM 12364059 camshaft does not come with the 3.4-liter crate engine like you say it does. The GM 12363220 camshaft comes with that engine. Go here to see for yourself
https://www.spoperformanceparts.com.

I have learned from my friend and engine builder with 30+ years experience that what the book says and what it actually is can be two very different things. You have to have the chambers cc’ed to know what the volume actually is. Even between two heads that fit the same engine of the same year the chamber volumes can vary. Eric’s heads could have 53 cc combustion chambers or they could be 45 cc. With GM outsourcing their parts and their poor manufacturing tolerances no print, book, or any other written document can be trusted. Its only with high quality high dollar after market manufacturers like J&E pistons that you actually get what they say you get in the book.

The reason why you cannot use the DOHC or stock 3.4-liter pistons in the 2.8 & 3.1-liter engines is because the 3.4-liter engine has a 3.620” bore and the 2.8 & 3.1-liter engines have a 3.50” bore. You would have to over bore a 2.8 & 3.1-liter engine .120” just to make standard pistons fit those engines. That cannot be safely done. The 3.4-liter block is allot beefier than the 2.8 & 3.1-liter engines with thicker cylinder walls and ribbed sides.

I got the piston numbers wrong. I have the same pistons that fierosound posted in the picture, H684CP. I already said this. If you have pistons with a 10-cc dish volume than your compression ratio would go up from 8.2-8.4. If your deck height is 0 on that same engine than your compression goes up to 8.67. You cannot go by what they say on their web site about compression ratios, You would be just guessing again. The cold hard facts are my heads have a largest 51.5 cc volume and with my heads on a 3.1-liter engine with a .016” deck height and a .020 over bore the compression ratio would be 8.2-1. I went through the trouble of having my heads cc’ed professionally with my machinist and I checked my deck height just so I would not be guessing what the compression ratio on my engine is, no book can ague with those facts. Again this guy has thirty years experience building high performance and racing engines so I’m not going to argue with him when he tells me this stuff.

You are saying that stock after market replacement pistons are destroked to compensate for the increase in compression due to over boring the engine. In one of my engine builder books it does say that some stock replacement pistons are destroked to compensate for the increase in engine bore size. The best way to find out is to measure the stock piston against the replacement piston or at least call the piston manufacturer, otherwise again you are just guessing. The reason why Eric’s engine has weak top end power is because of the camshaft not the low compression ratio. The compression ratio effects the whole rpm band not just upper rpm’s. In fact static compression ratios have less of an effect on power as the engines rpm increases. Don’t NASCAR engines run with a relatively low 9.0-1 static compression ratios for a high performance engine that runs @ 8000 plus rpm?

You can extract allot more power form the 2.8-liter engine than just 150 horsepower!

N_Man, You have a good point and I’ll check that out. I think that would cause some problems with the intake manifolds not fitting properly and it would reek havoc with your valve train geometry but It could be done in theory. You would also have to have enough material on the deck to do that.

Eric, That may be a typo on their web site, I don’t know. When I ordered my GM 12363220 camshaft from their web site it said that the lifters came with the camshaft and the whole thing was $99 as a kit. Thinking that was a great deal I ordered that camshaft after testing it on my Dyno program against about twenty other camshafts (it was the best one for me). I got the camshaft a week later but without the lifters. I called the dealer about this and he said I had to order the lifters separately and that it would cost me another $100. I told them that on their web site it said the lifters came with the camshaft. They checked it out and found out that it was a typo on the web site so for my inconvenience they sent me the lifters for free. I lucked out on that one. The GM 12363220 and your camshaft have the same duration and lift so your camshaft is not really bigger than the GM 123663220. These camshafts are almost identical except that the exhaust opening and closing points are different, which is probably the second most important cam timing events from the performance standpoint.

To show you how much of a difference crankshaft stroke makes here is an engine dyno for a 2.8-liter engine with the 2.99 stroke. I used the same heads, 8.2 compression ratio, and exhaust as the first dyno I gave you with your 3.1-liter engine.
2.8-liter engine with GM 12364059 camshaft.
RPM Horsepower Torque
2000 60 157
2500 79 166
3000 101 177
3500 120 181
4000 136 178
4500 146 170
5000 149 156
5500 145 138
6000 133 117
6500 116 94

As you can see that camshaft makes more mid ranged power in a 2.8-liter engine than your 3.1 because of the lesser stroke. It now resembles the description in the GM performance Catalog. This engine actually makes more upper end power than your 3.1-liter engine does.

That engine in the same fiero as before will go 0-60 mph in 7.5 seconds and run the quarter mile in 15.5 seconds @ 87.5 mph.

Here are the numbers Dyno2000 comes up with for the completely stock 2.8-liter fiero engine for your reference. Even though they are not exactly the same as what GM advertises for the 2.8-liter engine it is important that we have a baseline to compare the improvements too.
RPM Horsepower Torque
2000 63 166
2500 83 173
3000 103 180
3500 118 177
4000 129 169
4500 134 156
5000 130 137
5500 118 113
6000 100 87
6500 79 64

Drapstip2000 says the stock 2.8-liter fiero with a 2925 lb. weight including me and five-speed transmission will go 0-60 mph in 8.1 seconds and run the quarter mile in 15.82 seconds @ 86 mph. The stock automatic fiero with the same stock 2.8 will go 0-60 mph in 8.7 seconds and run the quarter mile in 16.6 seconds @ 84.3 mph.

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[This message has been edited by 88formula (edited 02-07-2001).]

88 Formula you are correct. I was confusing the -059 cam with the -220 cam in regards to the cam used in the 3.4 crate engine. I remember printing out the V6 from the 98 performance parts catalog and I thought I remember it saying the -059 cam came with the crate engine. I admit I was wrong about that.

i too was going to get the -220 cam a year or so ago. i ordered it and when it came it didnt' come with the lifters. Te guy at the counter told me that it didn't say Camshaft kit like the others did. he was cool enought to send it back and get me the camshaft kit which was the -059 cam as I wanted that lift and duration. But even on that link you sent me it just says "Camshaft" The -059 says "Camshaft kit" meaning it comes with lifters. Looks like you did luck out as I payed $114 for my kit.

I think using .016 as a standard for all the people using the 3.1 conversion is not good but I guess some things need to be kept as a standard to give rough estimates. You did throw in the CR of a Zero deck so I guess it all works out. I have yet to have a piston test fitted into my block to see what the deck height is on mine.

88 Formula: what formula are you using to come up with compression ratio? I know you said you had that computer thingie but i thought the compression ratio was something like Bore x Stroke / CR +1

i had an excell file and i was doing these eqations and the only unknown i had was dish in the piston. I took a stab at it and said it was 8 cc's and that the quench area of the area between the head and the top of the piston came out to be around 7-8 cc's or so. with the pistons i had it came out to be around 8.8:1 if I am not mistaken. However Travis has that file as I emailed it to him and I somehow lost my copy. If he sees my email i would hope he would email it back to me so i can see what I actually got. i don't remember it exactly but i would still like to know where are computations differ. Also GT basterd has a copy of it too.

GT BASTERD email me at Shaun41178@aol.com if you still have that excel file of the compression ratios that I did.

I don't want to call you a liar or sound like I am a hard headed d!ck, I just have a hard time believing it and I really don't want to believe it either. I guess I just like to do all the calculations myself and see for myself. Personality trait I guess.

Things are starting to make sense at last. It's funny how GM makes you believe that the 59 cam is the thing to have while the 20 cam is actually a better choice. But now that I've looked over your dyno printouts, there really isn't much difference between the two. It probably wouldn't be worth the effort or money for me to swap them. I'd be better off replacing the exhaust and doing other bolt-on modifications and leave the internals alone. Now that you mention it, the idle on the car is rather tame without much lope. Seeing as how I rarely wind the motor up, the cam may be a reasonable one for me. Oh well, maybe I'll do what Shaun was thinking about all along and add nitrous. Any word on a chip, Shaun?

eric, go here for a chip, http://www.eidnet.org/local/westers_garage/

he made me a custom ship setup for my mods and nitrous. he can program you a chip for your 3.2 with 19# injectors and such. plus intake and exhaust mods too. he can even delete the egr function if you ask him to do that

please tell him that i sent you. i don't get any kickback from him its just that he hooked me up with a custom chip for my nitrous application so I want to try and help him out in any way. he is a really cool guy.

let me know what he says.

88,
you have a point about the intake and valvetrain geometry...
but couldnt you shorten the pushrods to compensate?
and have the intake machined to compensate?

i forgot to mention, i don't know if static compression ratio is different from regulr compression ratio but 88 Formula Nascar engines run compression ratios in the 14:1 range or even 15:1 not 9:1. That is why they use 117 octane race fuel and make 700 hp on only a 355 cubic inch engine. Just thought I would let you know.

Spinning to 9000 RPM give the specific output a litle boost as well...