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> Type 4 rebuild questions
mepstein
post Nov 19 2018, 08:14 PM
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What can I do to rebuild my 1.7 for more HP and torque but keep the original d-jet.

piston and cylinders
crank
camshaft
heads
?

I know I can't change the cam too much but is there one that will do better and still work with d-jet.

I know there is modern FI but I'm not interested. No carbs. I'm not looking for all out HP or dropping 10K on an engine kit. I just want a nice bump in power, if possible, while keeping a stock looking engine.
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Alapone
post Nov 20 2018, 11:09 AM
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Just curious, has anyone built a motor with a 66mm crank and 100 or 101mm or larger pistons, like a short stroke 2.1. Is it possible? what would the characteristics of that set up be>?
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Mark Henry
post Nov 20 2018, 05:16 PM
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QUOTE(BeatNavy @ Nov 20 2018, 07:05 AM) *

Mark (E) I'm doing a similar build right now. 2056, webcam, Hoffman heads, and stock-djet. Not to contradict Mr. Henry (who has a world more experience than I will ever have), but I thought something like this was good for north of 110 hp. Maybe anything less than 200 to Mark (H) just looks like 100-ish (IMG:style_emoticons/default/smile.gif)

I guess we shall see.


No, I consider myself as a realist...I find hany HP claims to be exaggeration, or to be more PC let's say "overly optimistic". (IMG:style_emoticons/default/biggrin.gif)
1.7 djet FI cam with 96mm P&C's and headers, I very much doubt if you could break 100hp.

QUOTE(mepstein @ Nov 19 2018, 10:39 PM) *


I do have a set of nos mahle 94mm P&C's. Also have a 2.0 crank. I don't know if either of these will fit or work to improve power. I was hoping to see 100 but I realize the stock 1.7 d-jet has limitations.

Weight reduction (of the car) will also help to increase performance.


Mark the 2.0 piston have a different pin to deck height, by eyeball at least .200". You will find the 1.7/1.8 vs 2.0 rod length to be different a corresponding amount. Even 15% is a huge increase, factor in the weight reduction and it would make a fun 914.


QUOTE(Alapone @ Nov 20 2018, 12:09 PM) *

Just curious, has anyone built a motor with a 66mm crank and 100 or 101mm or larger pistons, like a short stroke 2.1. Is it possible? what would the characteristics of that set up be>?


It could be done , but at the dollar level this engine will cost to make good HP on a stock motor it wouldn't give enough reward for the bucks. Again there's no replacement for displacement.
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Posts in this topic
mepstein   Type 4 rebuild questions   Nov 19 2018, 08:14 PM
Mark Henry   Webcam #73 96mm KB's for 66mm crank and move u...   Nov 19 2018, 08:58 PM
mepstein   Webcam #73 96mm KB's for 66mm crank and move ...   Nov 19 2018, 09:39 PM
Chris914n6   The big difference with Djets is ecu and injectors...   Nov 20 2018, 01:20 AM
BeatNavy   Mark (E) I'm doing a similar build right now. ...   Nov 20 2018, 06:05 AM
Racer   I know a bump to a 1911 was always popular for 1.7...   Nov 20 2018, 07:05 AM
saigon71   FAT 440 MP camshaft is great with D-jet. I think ...   Nov 20 2018, 07:08 AM
Literati914   Posted in the classifieds?, you amateur :poke: ...   Nov 20 2018, 09:35 AM
mepstein   Posted in the classifieds?, you amateur :poke: ...   Nov 20 2018, 01:01 PM
914Sixer   Correct me if I am wrong, but the stock 1.7 made 8...   Nov 20 2018, 09:42 AM
Racer   Correct me if I am wrong, but the stock 1.7 made ...   Nov 20 2018, 11:22 AM
porschetub   Correct me if I am wrong, but the stock 1.7 made...   Nov 21 2018, 02:03 AM
GregAmy   "Subscribing". My 2L street car is runni...   Nov 20 2018, 10:07 AM
yellowporky   getting ready to build up my 73 1.7 next month. T...   Nov 20 2018, 10:26 AM
Alapone   Just curious, has anyone built a motor with a 66mm...   Nov 20 2018, 11:09 AM
Mark Henry   Mark (E) I'm doing a similar build right now....   Nov 20 2018, 05:16 PM
914Sixer   My bad, I got on the wrong info line. 88 hp was f...   Nov 20 2018, 01:13 PM
Jamie   My bad, I got on the wrong info line. 88 hp was ...   Nov 20 2018, 02:41 PM
thelogo   If your stick in with djet = stay bone stock If y...   Nov 20 2018, 02:40 PM
mepstein   I already have 94mm Mahle P&C's, 2.0 crank...   Nov 20 2018, 02:50 PM
rgalla9146   I already have 94mm Mahle P&C's, 2.0 cran...   Nov 21 2018, 04:58 PM
mepstein   I already have 94mm Mahle P&C's, 2.0 cra...   Nov 21 2018, 05:15 PM
rgalla9146   [quote name='rgalla9146' post='2667542' date='Nov...   Nov 21 2018, 06:02 PM
mepstein   [quote name='rgalla9146' post='2667542' date='No...   Nov 21 2018, 06:16 PM
worn   [quote name='rgalla9146' post='2667542' date='Nov...   Nov 21 2018, 06:14 PM
JOEPROPER   I think you're right about looking at HP incre...   Nov 20 2018, 04:24 PM
TravisNeff   The CA spec 73 1.7 was 72 HP, lower than the 1.8 b...   Nov 20 2018, 05:03 PM
76-914   Leave it stock and keep the RPM's up. Those ar...   Nov 20 2018, 05:06 PM
jcd914   Stock 1.7L at 8.2:1 compression ratio was 80HP (72...   Nov 20 2018, 07:51 PM
mepstein   Stock 1.7L at 8.2:1 compression ratio was 80HP (7...   Nov 20 2018, 08:06 PM
worn   Stock 1.7L at 8.2:1 compression ratio was 80HP (...   Nov 20 2018, 09:09 PM
mepstein   [quote name='mepstein' post='2667271' date='Nov 2...   Nov 20 2018, 09:17 PM
Valy   The static CR doesn't say much without conside...   Nov 21 2018, 01:14 AM
JamesM   I think you are starting in the wrong place. the g...   Nov 21 2018, 03:18 AM
mepstein   I think you are starting in the wrong place. the ...   Nov 21 2018, 07:29 AM
scott_in_nh   Ditch the d-jet and you could do something like t...   Nov 21 2018, 11:21 AM
Front yard mechanic   You could always turbo   Nov 21 2018, 08:28 AM
ClayPerrine   You could always turbo OK.. I have to say it.....   Nov 21 2018, 01:13 PM
worn   You could always turbo OK.. I have to say it....   Nov 21 2018, 06:10 PM
Dave_Darling   "You can't turbo a 914!!!...   Nov 22 2018, 02:24 PM
914forme   Source a 2.0L bus intake and that keeps the D-Jet ...   Nov 21 2018, 04:31 PM
cgnj   Mark, Here is the link regarding the plenums.2270 ...   Nov 21 2018, 09:06 PM
ottox914   See the various builds linked in my sig. Very hap...   Nov 24 2018, 10:23 PM


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