building a 1911 from a 1.7, will my existing heads work? |
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building a 1911 from a 1.7, will my existing heads work? |
HAM Inc |
Aug 27 2011, 02:29 PM
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#21
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
QUOTE have you ever tried this with 2.0 liter heads? Some sort of cylinder ring might do the trick... Wondering if this setup, with the higher flowing heads, may get to that magic 40mpg number.... The nice thing about the long stroke-small bore is that the intent is to build torque at low speeds, which benefits/needs smaller ports for velocity. I suppose one could devise a way to install the 2.0 914 heads, but that would defeat the purpose of the design. For the street the longer the stroke the better IMO. I like my torque down low and lots of it. Sometime back Jake and I collaborated on a powerplant built to the 90.5 x 78.4 specs with 1.7Q heads that had 40x34mm valves and relocated plugs. IIRC it ended up in a Ghia that broke well over 40mpg hwy. |
pete-stevers |
Aug 27 2011, 03:22 PM
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#22
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saved from fire! Group: Members Posts: 2,641 Joined: 10-October 04 From: Abbotsford,BC, Canada Member No.: 2,914 Region Association: Pacific Northwest |
What type of carbs did you run in that set up?
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bam914 |
Aug 27 2011, 03:27 PM
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#23
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Member Group: Members Posts: 334 Joined: 23-November 03 From: Atlanta, Ga Member No.: 1,378 Region Association: None |
My dad has a 1911 in his 914. Len did the heads. They are 1.7L with 42I 36E. It is 9.0 to 1 and has a Raby cam in it. Not the 9550. He is running 40 webers with stock SS heat exhangers. It made 95whp and I think 105 wtq. It is a good engine that is not expensive to build.
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HAM Inc |
Aug 27 2011, 09:09 PM
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#24
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
QUOTE What type of carbs did you run in that set up? I don't remember what it ended up with. Once the heads left my shop I lost track of what they ended up using. The customer feedback came to me months (maybe more than a year) after I did the heads. QUOTE My dad has a 1911 in his 914. Len did the heads. They are 1.7L with 42I 36E. It is 9.0 to 1 and has a Raby cam in it. Not the 9550. He is running 40 webers with stock SS heat exhangers. It made 95whp and I think 105 wtq. It is a good engine that is not expensive to build. Yeah I know your dad is really happy with that engine. And it is a pretty affordable, reliable, easy upgrade. |
bradtho |
Aug 27 2011, 11:40 PM
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#25
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Member Group: Members Posts: 266 Joined: 22-December 09 From: Seattle, WA Member No.: 11,165 Region Association: None |
OK, so Ham says no-go on boring my OE 1.7 cylinders to 96mm. anybody know what you can bore them out to and still have a very reliable engine? this is my DD so reliability is a big thing for me.
Opinions on if I should give up on my OE cylinders and just get some chinese instead? I've been under the impression that the original german cylinders were generally of much higher quality and might be worth preserving. If that's all just typical anti-china internet hype, then maybe I'm better off getting the 96's? money-wise it's largely a wash, so ending up with the highest quality engine is really the goal with the cylinders. |
HAM Inc |
Aug 28 2011, 07:59 AM
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#26
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
I'm not going to comment on the Chinese cylinders other than to report that they don't all come out the same size, so if you do buy a set, take them to a shop along with the pistons and have the clearances measured.
If you do use the Chinese cylinders save/sell your good used 1.7 cylinders. They can be bored for 90.5 pistons for someone who wants to build the long stroke/small bore 2.liter. |
ripper911 |
Aug 28 2011, 05:38 PM
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#27
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corde pulsum tangite Group: Members Posts: 2,920 Joined: 25-April 10 From: Powder Springs, GA Member No.: 11,654 Region Association: South East States |
My dad has a 1911 in his 914. Len did the heads. They are 1.7L with 42I 36E. It is 9.0 to 1 and has a Raby cam in it. Not the 9550. He is running 40 webers with stock SS heat exhangers. It made 95whp and I think 105 wtq. It is a good engine that is not expensive to build. He says the one that he built for me is very similar, and I am very happy with it. (IMG:style_emoticons/default/driving.gif) |
Dave_Darling |
Aug 28 2011, 06:21 PM
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#28
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914 Idiot Group: Members Posts: 14,974 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
There were 96es that fit 1.7 heads. They were very thin, and tended to leak and warp. That could be where some of the confusion comes from--it can be done, but usually leads to problems.
--DD |
rhodyguy |
Jun 25 2015, 06:12 PM
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#29
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,042 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
interesting what you can find with a tablet. jake's take on heads, what fits and what doesn't without any additional machining in particular. scroll down a bit.
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LukeD |
Jun 25 2015, 10:23 PM
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#30
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Member Group: Members Posts: 254 Joined: 14-November 04 From: Atascadero, CA Member No.: 3,117 Region Association: None |
That's it!! (IMG:style_emoticons/default/piratenanner.gif) Thanks for the link. Below is some cut and paste info from the other site. -7.7:1 -RAT 9550 -1.7"Q" heads opened to 105mm register size (2.0) with 42X36 valves and no port work, by HAM. -Relocated spark plugs -stock crank and rods -RAT 96mm KB pistons and cylinders -RAT oil pump -36mm Weber carbs -Mallory Unilite dizzy This is a D Jet compatible Combo. Will my 1.7 liter D-jet setup work with a build like this or will it require modification? |
Dave_Darling |
Jun 26 2015, 08:49 AM
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#31
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914 Idiot Group: Members Posts: 14,974 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
It'll require some tweaking of the MPS, and possibly other adjustments.
--DD |
lonewolfe |
Aug 3 2015, 01:50 AM
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#32
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Senior Member Group: Members Posts: 819 Joined: 12-September 11 From: Oakland, CA Member No.: 13,549 Region Association: Northern California |
I'm not going to comment on the Chinese cylinders other than to report that they don't all come out the same size, so if you do buy a set, take them to a shop along with the pistons and have the clearances measured. If you do use the Chinese cylinders save/sell your good used 1.7 cylinders. They can be bored for 90.5 pistons for someone who wants to build the long stroke/small bore 2.liter. I know this thread is old but who makes the 90.5 Pistons and where do you buy them? Are these VW Type 1 Mahle "B" Pistons? |
914_teener |
Aug 3 2015, 09:48 AM
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#33
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914 Guru Group: Members Posts: 5,193 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
I'm not going to comment on the Chinese cylinders other than to report that they don't all come out the same size, so if you do buy a set, take them to a shop along with the pistons and have the clearances measured. If you do use the Chinese cylinders save/sell your good used 1.7 cylinders. They can be bored for 90.5 pistons for someone who wants to build the long stroke/small bore 2.liter. I know this thread is old but who makes the 90.5 Pistons and where do you buy them? Are these VW Type 1 Mahle "B" Pistons? I am still contemplating this as well as I get ready to pull the trigger. I seem to recall the Len was no longer doing the Q heads. I also have heard that the long stroke smaller bore engine produces lots of torque quickly with those heads meaning the 1.7 heads. Anybody have any experience with a longer stroke smaller bore engine? No hijack intended. |
lonewolfe |
Aug 3 2015, 10:35 AM
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#34
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Senior Member Group: Members Posts: 819 Joined: 12-September 11 From: Oakland, CA Member No.: 13,549 Region Association: Northern California |
Who makes and sells the 90.5 stroker pistons?
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rhodyguy |
Aug 3 2015, 10:37 AM
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#35
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,042 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
read jakes take on the 1.8 heads. in most cases they are the least expensive to acquire.
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914work |
Nov 2 2017, 02:18 PM
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#36
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Member Group: Members Posts: 291 Joined: 9-November 11 Member No.: 13,762 Region Association: None |
Resurrection:
No one appeared to answer the question for sourcing the small dia. P&C's referred to? Pin height? Off the shelf or custom? The other related question is the 78.4mm rod length, is that an existing Rod from another application or a custom rod? I ask because I have 3 or 4 core 1.7L's hanging around here & I should do SOMETHING with them... |
Dave_Darling |
Nov 2 2017, 05:28 PM
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#37
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914 Idiot Group: Members Posts: 14,974 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Check with AA Pistons. The 90.5 were a stock replacement overbore part, at least in theory.
When you talk about the rod length, do you mean "rods for a crank that has a 78.4mm stroke"? If so, I believe those cranks are usually ground with Type I journals, or sometimes with Rabbit journals. There are a lot of aftermarket rods you can get for either of those motors. --DD |
914_teener |
Nov 2 2017, 07:09 PM
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#38
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914 Guru Group: Members Posts: 5,193 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
Wow....it is hard to believe that was two years ago now.
I ended up selling my 1.8 heads for that reason and then the 2.0 castings became available. |
Montreal914 |
Nov 2 2017, 08:14 PM
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#39
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Senior Member Group: Members Posts: 1,532 Joined: 8-August 10 From: Claremont, CA Member No.: 12,023 Region Association: Southern California |
About 30 years ago (IMG:style_emoticons/default/rolleyes.gif) I had a 1776cc type 1 (Beetle) which was 69 x 90.5.
They were CIMA pistons. Could this be what this old thread was referring to? (IMG:style_emoticons/default/confused24.gif) |
914work |
Nov 2 2017, 08:51 PM
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#40
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Member Group: Members Posts: 291 Joined: 9-November 11 Member No.: 13,762 Region Association: None |
About 30 years ago (IMG:style_emoticons/default/rolleyes.gif) I had a 1776cc type 1 (Beetle) which was 69 x 90.5. They were CIMA pistons. Could this be what this old thread was referring to? (IMG:style_emoticons/default/confused24.gif) I was unaware a T1 cylinder could be mated to a T4 case. Arent the registers ..smaller? @Dave yes I should have used "Rods / crank to attain" a 78.4mm stroke. So as Jake likes to say , its all in the Combo...? |
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