jp4s engine ( 125bhp alloy inlet model ) cam questions

2nd July 2013, 13:17

Afternoon, Right iv got a 110 bhp jp4 and a jp4s engine im looking at buying a kent pt50 off a mate made for the j4 engine also has kent verniers my question is would this cam fit in the jp4s head without risk of hitting the pistons... as the jp4s head has HUGE cams compaired to the jp4 when you look at them next to eachother.. or should use a j4 bottom end any advice really im prepared to do anything to build a nice little motor the jp4 will be going in my furio so was thnking cam the jp4s for my project car and then use the jp4s larger standard cams in my jp4
Or would I be better buying phase threes made for the jp4? Anyone have experience with power gains etc

3rd July 2013, 11:26

Hi, i have jp4 enngine with kent pt50 cams for j4. They fit without any problems. It made 139bhp with them,VTS Alloy manifold and remap.

3rd July 2013, 12:12

I made allot more than that with just j4 cams in my jp4 engine, 149bhp at the crank unmapped on sitech rollers iirc 132 at wheels (I can't remember but was about that), was quite quick actually - wish I kept it and mapped the fucker, cheap alternitive too! Can get the cams for about £15

Although my engine was built by a company (can't remember the name but can find out)

3rd July 2013, 18:10

I have seen this a lot on the site JP4. I have just bought a VTS C2 JP4 engine. The lad was quite excited about this engine , but why. Is there something different about it i.e stronger / lighter than a Saxo VTS / GTi. Lifting this out of the van this evening I wouldn't say it was a light engine. Is it the fact it has a cast iron block??

I have only just bought a VTR 8v so looking into the conversion and quite honestly absorbing as much info as I can from a very knowledgeable site.

Basically what is the difference please

3rd July 2013, 18:31

Quote:

Originally Posted by Rallynavigator

I have seen this a lot on the site JP4. I have just bought a VTS C2 JP4 engine. The lad was quite excited about this engine , but why. Is there something different about it i.e stronger / lighter than a Saxo VTS / GTi. Lifting this out of the van this evening I wouldn't say it was a light engine. Is it the fact it has a cast iron block??

I have only just bought a VTR 8v so looking into the conversion and quite honestly absorbing as much info as I can from a very knowledgeable site.

Basically what is the difference please

The main difference is.. its a newer engine, so therefor its easier to find really low mile-age engines, and in very good condition, 99% of J4 parts are a straight swap onto this engine, the only 1% is really just the inlet..

IRRC the differenced are the heads, the cams in the head on the JP4 are more "economical", the valves are bigger though, that is your short answer.

The pistons are not cut-slotted irrc, and the gudgeon pins on the rod's (IRRC) are 2mm smaller than J4 - someone can correct me on this 2 ive just mentioned, i could be wrong.

The differences is not major but i LOVED my JP4s engine more than i have a crazy cammed J4, and my jp4 had only standard j4 cams in it (they act like high lift cams in a way)

3rd July 2013, 20:30

Quote:

Originally Posted by ThrushMotorsport

I made allot more than that with just j4 cams in my jp4 engine, 149bhp at the crank unmapped on sitech rollers iirc 132 at wheels (I can't remember but was about that), was quite quick actually - wish I kept it and mapped the fucker, cheap alternitive too! Can get the cams for about £15

Although my engine was built by a company (can't remember the name but can find out)

My one was 110 bhp stock. I was hoping to get about 150bhp, but 139 was the maximum, you know every rollers are different. Any way, now i have turbo on it and is about 200bhp, not bad for 850kg car.

3rd July 2013, 21:49

use the complete S engine with whatever cams fit, use the inlet with a cable conversion T/B if the inlet fits in a saxo/106.

3rd July 2013, 21:59

Got myself some phase threes sorted for the jp4s Now so my pt50s will be for sale question is now will kent vernier pullys work on the newman cams and jp4s engine ? As for the jp4 its having the jp4s cams on I and put in my daily! Also does the jp4s have stronger springs standard or will I need to change them too

4th July 2013, 00:08

Iirc if you are using j4 ph3 cams, use the j4 springs in the jp4, I don't think the standard jp4 ones can lift as much as the j4 ones - if I'm wrong, someone correct me but I'm pretty sure

4th July 2013, 01:21

Cams are for a c2 vts so same engine but im thinking using a j4 ecu woth higher limiter ill need j4 springd

9th July 2013, 17:57

usually the practice is you only use the valves in the jp4 head and swap everything over from the j4, thats what i did on mine and what i know many others do 2..

9th July 2013, 18:06

im in the process of stripping my jp4 head down, im using j4 springs, caps, cams and pullies with the jp4 collets and followers as these are apparently the same