What engine horsepower do I want
12-30-2008, 08:50 PM
#1
Racer
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St. Jude Donor '03 & '05
What engine horsepower do I want
Up until last Friday the plan was to buy a ZZ4 crate engine to bolt up to my new TKO I'm planning on ordering in January.
The ZZ4 is a 355 HP engine as I'm sure most of you know.
Last Friday I got this idea that maybe I could have my present 350 CID rebuilt by a very reputable shop in the next town (Reid's Automotive).
I called them up and asked a few questions and then after getting off the phone decided this seems like a better way to go. Within an hour of the phone call I was getting a tour of his machine shop and I was sold on having my existing engine rebuilt. He would do a complete rebuild and dyno it afterwards so I now exactly what I'm getting which will also help me choose the correct TKO (TKO-500 or 600)
Now the question is, I was planning on a 355HP ZZ4 but now I have my choice to go as high as 400HP + if I want to spend the $$.
I'm not interested in racing the car next to me at every set of lights but I do want to have a reasonably quick car that I can get on once in a while when I feel spunky. Or when I'm on the highway doing 65 MPH I can step on it and pass the car in front of me with no problem.
What's a decent HP range to shoot for without building a race engine.
I'm thinking around 375HP. Will that get me what I'm looking for??
Thanks, Mark
The ZZ4 is a 355 HP engine as I'm sure most of you know.
Last Friday I got this idea that maybe I could have my present 350 CID rebuilt by a very reputable shop in the next town (Reid's Automotive).
I called them up and asked a few questions and then after getting off the phone decided this seems like a better way to go. Within an hour of the phone call I was getting a tour of his machine shop and I was sold on having my existing engine rebuilt. He would do a complete rebuild and dyno it afterwards so I now exactly what I'm getting which will also help me choose the correct TKO (TKO-500 or 600)
Now the question is, I was planning on a 355HP ZZ4 but now I have my choice to go as high as 400HP + if I want to spend the $$.
I'm not interested in racing the car next to me at every set of lights but I do want to have a reasonably quick car that I can get on once in a while when I feel spunky. Or when I'm on the highway doing 65 MPH I can step on it and pass the car in front of me with no problem.
What's a decent HP range to shoot for without building a race engine.
I'm thinking around 375HP. Will that get me what I'm looking for??
Thanks, Mark
12-30-2008, 09:42 PM
#2
Le Mans Master
Horsepower is very subjective. Also, you can never have too much.
If you go old ratings, then it seems like you have a lot (300 hp, 350 hp, 375 hp) but under the new ratings, those come out much lower. So 300 hp today is a LOT more than 300 hp 40 years ago.
You need to know if he is talking gross, net, rear wheel, flywheel, with accessories, as installed, bare engine, and so on.
The old SAE gross 350 hp was a very nice and comfortable machine, with enough to have fun. By the same standards, 375 hp was a blast and the edge of civility. 400 or more horse in a small block would have been edgy on the street.
Today, 300 hp, like in an LS1, is very civilized, yet will yank your head like the 375 of yester year.
With current cams, heads, and other mods, you can get that 375 or 400 hp in a much more civilized package, so you really need to try it on somehow.
Ask if he has any customers with those engines who would take you for a ride.
If you go old ratings, then it seems like you have a lot (300 hp, 350 hp, 375 hp) but under the new ratings, those come out much lower. So 300 hp today is a LOT more than 300 hp 40 years ago.
You need to know if he is talking gross, net, rear wheel, flywheel, with accessories, as installed, bare engine, and so on.
The old SAE gross 350 hp was a very nice and comfortable machine, with enough to have fun. By the same standards, 375 hp was a blast and the edge of civility. 400 or more horse in a small block would have been edgy on the street.
Today, 300 hp, like in an LS1, is very civilized, yet will yank your head like the 375 of yester year.
With current cams, heads, and other mods, you can get that 375 or 400 hp in a much more civilized package, so you really need to try it on somehow.
Ask if he has any customers with those engines who would take you for a ride.
12-30-2008, 10:09 PM
#3
Drifting
Extracting 400 HP from an old school 350 will compromise the driveability of the engine. You can basically build a 70 LT1 spec engine, solid lifters, do some port work, throw on headers, a big 750 carb, 11:1 pistons and get close to 400 HP. I had this engine, it was a blast to drive but wore you out after a couple of hours. Also, chasing high octane gas was a never ending PIA.
Option 2. Build a "modern" 350 with full roller internals, high flow heads, 1.6 ratio rockers and a resonable compression ratio. You could get close to 400 HP on pump gas without going too radical of a cam. This will not be cheap to build.
I do not know what your engine builder quoted for a price. Is the 400 HP net, gross???
I would seriously consider a GM crate motor if you want 400+HP. You can get a 383 CI/425HP stroker for $5K and change.
It is nice to think about having lots of horsepower. Getting that out of 350 engine will either cost a lot of money or sacrifice driveability/durability, or both.
Option 2. Build a "modern" 350 with full roller internals, high flow heads, 1.6 ratio rockers and a resonable compression ratio. You could get close to 400 HP on pump gas without going too radical of a cam. This will not be cheap to build.
I do not know what your engine builder quoted for a price. Is the 400 HP net, gross???
I would seriously consider a GM crate motor if you want 400+HP. You can get a 383 CI/425HP stroker for $5K and change.
It is nice to think about having lots of horsepower. Getting that out of 350 engine will either cost a lot of money or sacrifice driveability/durability, or both.
12-30-2008, 11:08 PM
#4
Drifting
I had the same issue....ZZ4 or rebuild my engine to a 383. I chose a modified ZZ4 (418 fw HP). I really like it, but.....I wish I had gone with the 383 option.
MORE TORQUE.
MORE TORQUE.
12-31-2008, 05:34 AM
#6
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I just went through the same thing withy my 350, rebuild or buy crate. Do you want roller cam or hydraulic cam, that was the biggest difference in $$. I went with a kit with Trick flow heads and kept my hydraulic cam which I guess gives up 20-25HP $$ = HP. Just getting it back together good now. The 383 was going to be 6K when finished and I believe I have under 3K now. Friend put it together for $850 and that was my deciding factor to stick with my 355 block which is a large journal crank.
I hope it stays together, LOL. Good luck on whatever you choose.
I hope it stays together, LOL. Good luck on whatever you choose.
12-31-2008, 08:30 AM
#8
Safety Car
larry
12-31-2008, 08:37 AM
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Reid's Automotive has an excellent reputation. They have been around a long time here in Mass. and I have never heard anything but good about their engine building skills.
Horsepower is fun but the more you have, the more you need to be sure you don't have any weak links in your drivetrain. Make sure your clutch, tranny and rear end can handle big horsepower. The weak links will be exposed quickly once you start getting over 400 horsepower. 400 HP is a nice figure though. Good luck
Horsepower is fun but the more you have, the more you need to be sure you don't have any weak links in your drivetrain. Make sure your clutch, tranny and rear end can handle big horsepower. The weak links will be exposed quickly once you start getting over 400 horsepower. 400 HP is a nice figure though. Good luck
12-31-2008, 09:24 AM
#10
Melting Slicks
I am working right now with my engine builder on a similar question. He is recommending a 383 (torque.. echoing the "no replacment for displacement"), roller cam (rapid openning and closing allows better performance at low rpm without sacrificing high end), and really good heads (at least Vortec fast burn, and even better AFR's). He thinks the ZZ383 is a very good deal.
Harry
Harry
12-31-2008, 10:05 AM
#11
Le Mans Master
Engine
Regarding your transmission, you mentioned a TKO 500/600. Once you make your engine selection, check what gear ratio you are going to use. I have a 4:10 and ended up with a TKO 600. The 500 did not give me enough of an overdrive final ratio for parkway driving. Too high of a ratio (low numerical number) on a 600 will not keep your engine in its power band for highway driving. Jerry
12-31-2008, 10:48 AM
#12
Safety Car
Reid's Automotive has an excellent reputation. They have been around a long time here in Mass. and I have never heard anything but good about their engine building skills.
Horsepower is fun but the more you have, the more you need to be sure you don't have any weak links in your drivetrain. Make sure your clutch, tranny and rear end can handle big horsepower. The weak links will be exposed quickly once you start getting over 400 horsepower. 400 HP is a nice figure though. Good luck
Horsepower is fun but the more you have, the more you need to be sure you don't have any weak links in your drivetrain. Make sure your clutch, tranny and rear end can handle big horsepower. The weak links will be exposed quickly once you start getting over 400 horsepower. 400 HP is a nice figure though. Good luck
12-31-2008, 11:29 AM
#13
Burning Brakes
I was going to have my old 350 turned into a 383 stroker by a very good speed shop locally, but the cost (and my other expenses which seemed to have risen immensely recently) changed my mind to do it slowly and for less, in my garage. I already had the carb, intake and aluminum heads for this project, so I ordered a short block 383 from a company that was recommended by a couple of people on this forum. It's a Street Thunder 383 (3.750" Stroker 350) with ALL FORGED rotating assembly. The base entry level with cast stuff was about $1650. Mine was $2249. with all forged. In my opinion, go with more dispacement if you can. PM if you want info.
12-31-2008, 12:22 PM
#14
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St. Jude Donor '03 & '05
Reid's Automotive has an excellent reputation. They have been around a long time here in Mass. and I have never heard anything but good about their engine building skills.
Horsepower is fun but the more you have, the more you need to be sure you don't have any weak links in your drivetrain. Make sure your clutch, tranny and rear end can handle big horsepower. The weak links will be exposed quickly once you start getting over 400 horsepower. 400 HP is a nice figure though. Good luck
Horsepower is fun but the more you have, the more you need to be sure you don't have any weak links in your drivetrain. Make sure your clutch, tranny and rear end can handle big horsepower. The weak links will be exposed quickly once you start getting over 400 horsepower. 400 HP is a nice figure though. Good luck
The Tremec TKO will be new, the clutch is a Centerforce Dual Friction that has about 13K easy miles on it, so the only issue could be the rear end which has about 13K miles on it also so hopefully it'll be OK.
Most of the terms you guys are using is beyond my limited knowledge base. I'm planning on just telling the engine shop what type of HP and torque I'm looking for and letting them decide the best way to get there as far as part selection.
It sounds like I should aim for about 400HP based on everyones input.
All other comment welcome.
Thanks again and happy New Year, Mark
12-31-2008, 01:07 PM
#16
Drifting
Bsed upon what you've said and all of the feedback, this is what I would suggest you should tell your engine builder:
> Small Block 383 Cubic Inch engine, targeting 400 to 425 HP at the flywheel, torque > 400 ft-lbs.
> You want around 10:1 compression ratio
> Since you don't plan on racing the car, you can save some money by specing a CAST crankshaft (instead of forged).
> If your block is not already a 4 bolt main, you may want to consider just having your builder start with a new short block. This is the bottom section of the engine, including crankshaft & pistons...No heads.
That would be a good starting point for discussion with the engine builder. He will know what to do from there.
Are you going with a carb or EFI?
> Small Block 383 Cubic Inch engine, targeting 400 to 425 HP at the flywheel, torque > 400 ft-lbs.
> You want around 10:1 compression ratio
> Since you don't plan on racing the car, you can save some money by specing a CAST crankshaft (instead of forged).
> If your block is not already a 4 bolt main, you may want to consider just having your builder start with a new short block. This is the bottom section of the engine, including crankshaft & pistons...No heads.
That would be a good starting point for discussion with the engine builder. He will know what to do from there.
Are you going with a carb or EFI?
12-31-2008, 01:20 PM
#17
Race Director
.
My choice if I had to build another engine is to make your present engine into a .030 over 1970 LT1 {355}. Its not that radical and can use 93 pump gas but its the best 350 GM ever put together. A very reliable engine with all final ratios. Hundreds of 1970 Vettes and Z-28`s were built with that option. A tried and proven combination that commands respect immediately, and also suggested by a earlier post.
There is only one problem and that's the point that todays Vette owners are afraid of HP but want that type of performance and only get close. Go all the way and not be disappointed as others have complained about by not taking the extra step to get it. Nice thing about that engine its all STOCK with over the counter parts. No need for fancy bolt on crap that messes up that proven combination. Why do you think a 70 LT1 has become one of the most desired Vettes. Any thing less than a 70`s is a cop out. Do it right the first time as you can scrap a lot of parts and money that will not give that power if your not satisfied. Remember the NASCAR engines are ONLY 355 ci....Inches are nice but not necessary and a 70 LT1 engine proves it.....
My choice if I had to build another engine is to make your present engine into a .030 over 1970 LT1 {355}. Its not that radical and can use 93 pump gas but its the best 350 GM ever put together. A very reliable engine with all final ratios. Hundreds of 1970 Vettes and Z-28`s were built with that option. A tried and proven combination that commands respect immediately, and also suggested by a earlier post.
There is only one problem and that's the point that todays Vette owners are afraid of HP but want that type of performance and only get close. Go all the way and not be disappointed as others have complained about by not taking the extra step to get it. Nice thing about that engine its all STOCK with over the counter parts. No need for fancy bolt on crap that messes up that proven combination. Why do you think a 70 LT1 has become one of the most desired Vettes. Any thing less than a 70`s is a cop out. Do it right the first time as you can scrap a lot of parts and money that will not give that power if your not satisfied. Remember the NASCAR engines are ONLY 355 ci....Inches are nice but not necessary and a 70 LT1 engine proves it.....
12-31-2008, 01:29 PM
#18
Safety Car
If I was starting over (owned my 66 aprox 15 years) & IF my 427 needs major work & wont hold oil pressure will go with a 383 / 425 Chevy Engine .........just my 2 cents 
12-31-2008, 01:30 PM
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My choice if I had to build another engine is to make your present engine into a .030 over 1970 LT1 {355}. Its not that radical and can use 93 pump gas but its the best 350 GM ever put together. A very reliable engine with all final ratios. Hundreds of 1970 Vettes and Z-28`s were built with that option. A tried and proven combination that commands respect immediately, and also suggested by a earlier post.
There is only one problem and that's the point that todays Vette owners are afraid of HP but want that type of performance and only get close. Go all the way and not be disappointed as others have complained about by not taking the extra step to get it. Nice thing about that engine its all STOCK with over the counter parts. No need for fancy bolt on crap that messes up that proven combination. Why do you think a 70 LT1 has become one of the most desired Vettes. Any thing less than a 70`s is a cop out. Do it right the first time as you can scrap a lot of parts and money that will not give that power if your not satisfied. Remember the NASCAR engines are ONLY 355 ci....Inches are nice but not necessary and a 70 LT1 engine proves it.....
My choice if I had to build another engine is to make your present engine into a .030 over 1970 LT1 {355}. Its not that radical and can use 93 pump gas but its the best 350 GM ever put together. A very reliable engine with all final ratios. Hundreds of 1970 Vettes and Z-28`s were built with that option. A tried and proven combination that commands respect immediately, and also suggested by a earlier post.
There is only one problem and that's the point that todays Vette owners are afraid of HP but want that type of performance and only get close. Go all the way and not be disappointed as others have complained about by not taking the extra step to get it. Nice thing about that engine its all STOCK with over the counter parts. No need for fancy bolt on crap that messes up that proven combination. Why do you think a 70 LT1 has become one of the most desired Vettes. Any thing less than a 70`s is a cop out. Do it right the first time as you can scrap a lot of parts and money that will not give that power if your not satisfied. Remember the NASCAR engines are ONLY 355 ci....Inches are nice but not necessary and a 70 LT1 engine proves it.....
NASCAR run's 355's because of rules, not superiority. Same reason Pro-stock is run with 500 c.i. engines, not 672's.
12-31-2008, 01:49 PM
#20
Drifting
.
My choice if I had to build another engine is to make your present engine into a .030 over 1970 LT1 {355}. Its not that radical and can use 93 pump gas but its the best 350 GM ever put together. A very reliable engine with all final ratios. Hundreds of 1970 Vettes and Z-28`s were built with that option. A tried and proven combination that commands respect immediately, and also suggested by a earlier post.
There is only one problem and that's the point that todays Vette owners are afraid of HP but want that type of performance and only get close. Go all the way and not be disappointed as others have complained about by not taking the extra step to get it. Nice thing about that engine its all STOCK with over the counter parts. No need for fancy bolt on crap that messes up that proven combination. Why do you think a 70 LT1 has become one of the most desired Vettes. Any thing less than a 70`s is a cop out. Do it right the first time as you can scrap a lot of parts and money that will not give that power if your not satisfied. Remember the NASCAR engines are ONLY 355 ci....Inches are nice but not necessary and a 70 LT1 engine proves it.....
My choice if I had to build another engine is to make your present engine into a .030 over 1970 LT1 {355}. Its not that radical and can use 93 pump gas but its the best 350 GM ever put together. A very reliable engine with all final ratios. Hundreds of 1970 Vettes and Z-28`s were built with that option. A tried and proven combination that commands respect immediately, and also suggested by a earlier post.
There is only one problem and that's the point that todays Vette owners are afraid of HP but want that type of performance and only get close. Go all the way and not be disappointed as others have complained about by not taking the extra step to get it. Nice thing about that engine its all STOCK with over the counter parts. No need for fancy bolt on crap that messes up that proven combination. Why do you think a 70 LT1 has become one of the most desired Vettes. Any thing less than a 70`s is a cop out. Do it right the first time as you can scrap a lot of parts and money that will not give that power if your not satisfied. Remember the NASCAR engines are ONLY 355 ci....Inches are nice but not necessary and a 70 LT1 engine proves it.....
You describe almost the exact engine I had in my 4:11 geared LT1. It was a blast to drive for short trips. I would not suggest this engine configuration for the OP. You will have issues with 93 octane fuel and be forever chasing timing, fuel and additives to make it run well. I still contend pushing 400 HP out of a old school 350 will inevitably lead to driveabililty and fuel issues that you do not want to deal with for a daily driver type car.
It you ask the enginer builder to build a 400HP 350 I am sure he will accommodate. A 383 is a better choice for the HP figures desired for many reasons.