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pilothyer |
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#1
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Member ![]() ![]() ![]() Group: Members Posts: 838 Joined: 21-May 08 From: N. Alabama Member No.: 9,080 Region Association: South East States ![]() |
I am interested in building a 2270 engine. From what I can see I will need a stroker crank with a 78 mm throw. I am concerned about which rod to choose. I have seen stroker cranks with VW type 1 journals as well as 2.0 liter and chevy. I have noticed variations in rod lengths as well. I am in need of some advise on a good, proven combination. I know there are many good engine builders on his forum that could share their knowledge on this subject so please do...............Thanks
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Hine62 |
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#2
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Member ![]() ![]() Group: Members Posts: 132 Joined: 4-October 12 From: Binghamton, NY Member No.: 15,000 Region Association: None ![]() |
Check out:
Your Current Type IV Build Engine Building I know there are treads on journal size. I found them in a google search. Hine62 |
Mark Henry |
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#3
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that's what I do! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada ![]() |
Use the type 1 rod journal, stock type 1 length CB rod. They have to be clearanced or it will hit a cam lobe. Cam also has to be a reduced base circle cam.
I'd only use the Buick (Chevy) journal on a 80+mm and I'd never use a stock rod on a stroker. |
grimmel |
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#4
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grimmel ![]() Group: Members Posts: 5 Joined: 29-September 11 From: Sacramento, CA Member No.: 13,623 Region Association: Central California ![]() |
OR....insert a used non-turbo Subie 2.5....and never worry again...much cheaper in the long or short run....if the engine breaks....good used engines are available for less than $800....plus you have more HP & EFI... great drivability & better mpg & more torque.... just remember to have Dr. Evil rebuild the stock trans for Subie torque curve.......
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pilothyer |
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#5
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Member ![]() ![]() ![]() Group: Members Posts: 838 Joined: 21-May 08 From: N. Alabama Member No.: 9,080 Region Association: South East States ![]() |
Use the type 1 rod journal, stock type 1 length CB rod. They have to be clearanced or it will hit a cam lobe. Cam also has to be a reduced base circle cam. I'd only use the Buick (Chevy) journal on a 80+mm and I'd never use a stock rod on a stroker. Thanks for that information.........I have noticed that the crank with the Type 1 journal is available in 78 and 78.4 mm which would be the better choice? |
Jetsetsurfshop |
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#6
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Senior Member ![]() ![]() ![]() Group: Members Posts: 815 Joined: 7-April 11 From: Marco Island Florida Member No.: 12,907 Region Association: South East States ![]() |
I did a 78mm crank and had to clearance the case. My engine is a 2258. 78x96. I did type 1 journals also.
My connecting rods are 5.394 with 22mm wrist pins. We had to modify the rods also to clear the cam, even with a reduced base circle. This was super rewarding to build the engine and then thrash it on the track. Just remember that HP=heat. Good luck (IMG:style_emoticons/default/beer.gif) |
Jake Raby |
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#7
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
QUOTE . Just remember that HP=heat. Not if it adds efficiency. Its all in the combo. |
craig downs |
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#8
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Senior Member ![]() ![]() ![]() Group: Members Posts: 769 Joined: 25-November 05 From: mira loma ca. Member No.: 5,189 Region Association: Southern California ![]() |
That's true, my head temp always run at 275 - 300 most of the time and only gets up to 325 on a climb.
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Jetsetsurfshop |
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#9
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Senior Member ![]() ![]() ![]() Group: Members Posts: 815 Joined: 7-April 11 From: Marco Island Florida Member No.: 12,907 Region Association: South East States ![]() |
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Jake Raby |
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#10
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
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Jetsetsurfshop |
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#11
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Senior Member ![]() ![]() ![]() Group: Members Posts: 815 Joined: 7-April 11 From: Marco Island Florida Member No.: 12,907 Region Association: South East States ![]() |
That's true, my head temp always run at 275 - 300 most of the time and only gets up to 325 on a climb. Oil temp is impacted by many variables, RPM and ambient temps are the biggest, by far. (IMG:style_emoticons/default/agree.gif) |
Hine62 |
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#12
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Member ![]() ![]() Group: Members Posts: 132 Joined: 4-October 12 From: Binghamton, NY Member No.: 15,000 Region Association: None ![]() |
I did a 78mm crank and had to clearance the case. My engine is a 2258. 78x96. I did type 1 journals also. My connecting rods are 5.394 with 22mm wrist pins. We had to modify the rods also to clear the cam, even with a reduced base circle. This was super rewarding to build the engine and then thrash it on the track. Just remember that HP=heat. Good luck (IMG:style_emoticons/default/beer.gif) What case did you start with? 1.7, 1.8, or 2.0 hine62 |
Jetsetsurfshop |
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#13
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Senior Member ![]() ![]() ![]() Group: Members Posts: 815 Joined: 7-April 11 From: Marco Island Florida Member No.: 12,907 Region Association: South East States ![]() |
I did a 78mm crank and had to clearance the case. My engine is a 2258. 78x96. I did type 1 journals also. My connecting rods are 5.394 with 22mm wrist pins. We had to modify the rods also to clear the cam, even with a reduced base circle. This was super rewarding to build the engine and then thrash it on the track. Just remember that HP=heat. Good luck (IMG:style_emoticons/default/beer.gif) What case did you start with? 1.7, 1.8, or 2.0 hine62 Its not a GA code engine. I always assumed it was a 1.7L. PO built it to a 2L. Then I blew it up shortly after. (IMG:style_emoticons/default/happy11.gif) |
DBCooper |
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#14
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14's in the 13's with ATTITUDE ![]() ![]() ![]() ![]() Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California ![]() |
QUOTE . Just remember that HP=heat. Not if it adds efficiency. Its all in the combo. Not correct. Efficient or not more HP equals more heat. That's physics. For proven 2270 parts combinations try www.shoptalkforums.com, the Type4um. Fifteen years of discussion there. What's "best" is a matter of opinion, but generally 96mm sleeves, a 78.4mm crank (offset ground 2.0) with VW T1 rod journals and T1 rods, I or H-beam. With that combination the piston pin height is different, so the Keith Black for the application depending on the rod length you choose. Chromoly pushrods and 44x38 heads with a split-duration cam like a Web 86b/163. Look on Shoptalk for specifics, there are a lot of variations on those basics. |
Jake Raby |
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#15
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
QUOTE . Just remember that HP=heat. Not if it adds efficiency. Its all in the combo. Not correct. Efficient or not more HP equals more heat. That's physics. Only if operating at WOT, or under heavy load, using that power. Time and time again we find larger engines, making more power, that run cooler. This is due to the engine producing higher efficiency, not using as much of the engine's power to propel the vehicle. We even see this when pushing around a 2 ton load. If the engine makes double the power, it still takes the same amount of power to propel the vehicle, meaning a lesser percentage of the larger engine's net power is being used, which means the engine sees less percentage of load when compared to stock. The car doesn't know that the engine is larger. |
DBCooper |
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#16
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14's in the 13's with ATTITUDE ![]() ![]() ![]() ![]() Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California ![]() |
Sure, if you never use WOT you won't produce more heat. So who builds a performance engine and never uses wide open throttle?
An internal combustion engine is only about 30 percent efficient and the other 70 is heat. No one changes that. If/when that higher HP performance engine gets onto a track or is driven for any amount of time at WOT or under load you need to disperse more heat. Making it more efficient only means the percentage you have to disperse is a bit less, but double the HP and it's still a LOT more heat, regardless. That's physics, no getting around it. |
davep |
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#17
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914 Historian ![]() ![]() ![]() ![]() ![]() Group: Benefactors Posts: 5,260 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada ![]() ![]() |
It really comes down to fuel consumption; fuel = heat.
Efficiency is converting the heat to mechanical energy; better efficiency leaves less heat wasted. Also, depends on the cooling system getting rid of the waste heat more effectively. |
Jake Raby |
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#18
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
QUOTE Sure, if you never use WOT you won't produce more heat. So who builds a performance engine and never uses wide open throttle? He's talking about a street car here. Sure he can use WOT without issue, because by the time the engine sees enough load to become heat soaked, the driver will either kill himself or will go to jail. Sustained periods of heavy load are the enemy, luckily when producing more power, the instances that warrant these sustained loads are reduced, on the street. When using this power on the street the cooling system has plenty of time to recover so heat soak does not occur. I see this in testing all the time, and its how I can build a 284 HP 2.9 liter T4 and have it run 75 degree cooler CHT on pump gas. This is how a lot of guys with all sorts of turbo charged engines can get away with running high boost levels. QUOTE An internal combustion engine is only about 30 percent efficient and the other 70 is heat. No one changes that. If/when that higher HP performance engine gets onto a track or is driven for any amount of time at WOT or under load you need to disperse more heat. Making it more efficient only means the percentage you have to disperse is a bit less, but double the HP and it's still a LOT more heat, regardless. That's physics, no getting around it. Odd, I never knew that you were a Physicist. |
DBCooper |
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#19
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14's in the 13's with ATTITUDE ![]() ![]() ![]() ![]() Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California ![]() |
Odd, I never knew that you were a Physicist. No need to be, Jake, just pay attention in high school. Nothing you've said changes the fact that more HP equals more heat. What you've said is that it doesn't matter for most people because they'll never generate enough extra heat to cause problems, or that part throttle doesn't create as much heat. Of course, but that wasn't the question. When you double the power (or potential power) you double the heat (or potential heat). That's a law of nature that you aren't changing. So your advice is to use part throttle to keep the heat down? Good to know. |
Jake Raby |
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#20
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
QUOTE So your advice is to use part throttle to keep the heat down? Good to know. My advice is to make so much power that all of it is never, ever needed. I never said that more power does not increase more heat, thats very basic, just like more fuel is always required to make more power to generate that heat. What I did say was a proper combination, that makes plenty of power can equal a cooler running street engine, and that engine can even use less fuel. Thats what I have been applying for 22 years. Have you EVER read a post where anyone complained of my engines running hot? Nope. All that said, it's all in the combo- yet it may take you over 1,000 tries to learn that. One thing is for sure, you damn sure won't learn it sitting in front of a monitor and keyboard. |
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