SJ’s “claimed uprated” primary RC injectors

[Gjk]

Are these injectors ‘actually’ uprated? I have a set fitted to my car as the originals died. I didn’t receive any paperwork with them to show/prove they were uprated when they were delivered. Anyone else got them fitted who can confirm or deny the claim?

[ragingfool35]

a lot has been said about RC injectors.  search and see for yourself

[Chillidoggy]

By using the term 'uprated', it hints at the original fitment being deficient in some way. As is usual, with no empirical evidence of a before and after dyno run, it's an unproven claim.

[Gjk]

8 hours ago, ragingfool35 said:

a lot has been said about RC injectors.  search and see for yourself

But, no one has agreed or dismissed the SJ claim in any of the posts.

 

1 hour ago, Chillidoggy said:

By using the term 'uprated', it hints at the original fitment being deficient in some way. As is usual, with no empirical evidence of a before and after dyno run, it's an unproven claim.

I think I agree with you Ian. Without some sort of documentation for each individual injector to validate its specification I can safely say that its a stock injector replacement (possibly with a better spray pattern).

I had hoped another forum member may have fitted the exact same from SJ’s but had been supplied with the injector spec. Mine were fitted four years ago while away having some restoration work done, and I didn’t receive any injector paperwork when the car was returned.

[Chillidoggy]

You’d need to see a comparison between the two. Claims of improved spray patterns etc need to be backed up with solid evidence, not arse-dynos.

I also wonder whether the secondaries are more of a fuel-dumping safety net, but that question needs to be answered by someone cleverer than me.

[NG5]

49 minutes ago, Gjk said:

Without some sort of documentation for each individual injector to validate its specification

I recently fitted a set from SJ and they did come with a test sheet for each injector giving flow rate, brake specific fuel consumption etc.

Mind you I have no idea if the data actually shows they are uprated as I don't have the equivalent data for the standard ones.

They certainly work better than the failing standard ones I had, and the standard ones are no longer available anyway, so all a bit academic

[Gjk]

5 minutes ago, NG5 said:

I recently fitted a set from SJ and they did come with a test sheet for each injector giving flow rate, brake specific fuel consumption etc.

Mind you I have no idea if the data actually shows they are uprated as I don't have the equivalent data for the standard ones.

That’s more information than I have @NG5. Unless someone has had the original injectors tested I don’t think I’ll ever know.

IIRC I think mine were replaced to cure a lumpy idle but, I can’t be sure as it was so long ago and the car wasn’t in my possession.

[Chillidoggy]

Might be worth a look at the RC website https://www.rcfuelinjection.com/

[Gjk]

4 minutes ago, Chillidoggy said:

Might be worth a look at the RC website https://www.rcfuelinjection.com/

Ah-ha, cheers Ian.

Does anyone know the RC part number?

[Barrykearley]

PL2-370 iirc.

ive had these in the S4s for a fair old while - they seem just fine

https://www.rcfuelinjection.com/Store/p/pl2-0370-peak-hold-injector

[Gjk]

Are these the ones that SJ’s claim are uprated, or did you get them from another source?

The S4s has a different VE from the SE and produces more boost, so would need to be a little more uprated.

[fjmuurling]

Here is some information I got from RC Engineering about their PL2-370 injectors. I have them in my SE. The two secondaries in my SE are Bosch D5B injectors.

The latency values for RC Fuel Injection’s PL2-0370 injectors are listed here:

		PL2-370
		Fuel Pressure (psi)
		35	40	43.5	45	50	55	60	65	70	75	80	85	90	95	100
Voltage (V)	9.0	0.518	0.588	0.684	0.774	0.845	0.928	0.936	0.982	1.009	1.013	1.019	1.021	1.035	1.046	1.076
	10.0	0.378	0.419	0.508	0.593	0.647	0.706	0.719	0.765	0.821	0.867	0.889	0.925	0.933	0.952	0.986
	11.0	0.309	0.356	0.426	0.509	0.584	0.621	0.654	0.678	0.733	0.783	0.810	0.812	0.814	0.841	0.889
	12.0	0.257	0.310	0.351	0.425	0.507	0.557	0.588	0.653	0.676	0.683	0.703	0.742	0.772	0.798	0.813
	13.0	0.188	0.247	0.285	0.364	0.465	0.518	0.539	0.580	0.602	0.613	0.664	0.708	0.739	0.755	0.773
	14.0	0.136	0.200	0.265	0.343	0.431	0.466	0.490	0.538	0.546	0.572	0.626	0.665	0.680	0.697	0.716
	15.0	0.067	0.170	0.244	0.322	0.390	0.414	0.442	0.496	0.503	0.531	0.559	0.604	0.622	0.638	0.659
	16.0	0.042	0.156	0.224	0.301	0.363	0.397	0.427	0.453	0.460	0.490	0.504	0.518	0.537	0.578	0.603
		Latency times are given in milliseconds

 

---

 

 

The dynamic and static flow rates for RC’s PL2-0370 injectors are listed here:

 

43.5 psi (3 BAR)

All flow rates are measured in cc/min.

All tests were performed at 13.8 V and 100 Hz.

PL2-370

10% (1.0ms)

20% (2.0ms)

30% (3.0ms)

40% (4.0ms)

50% (5.0ms)

60% (6.0ms)

70% (7.0ms)

80% (8.0ms)

90% (9.0ms)

100% (Static)

MIN PW1 (ms)

MAX PW2 (ms)

Flow Rate

26

63

100

137

174

211

249

286

323

371

0.27

9.41

1MIN PW = pulse width where the injector flow is semi-closed

2MAX PW = pulse width where the injector flow is semi-static

72.5 psi (5 BAR)

All flow rates are measured in cc/min.

All tests were performed at 13.8 V and 100 Hz.

PL2-370

10% (1.0ms)

20% (2.0ms)

30% (3.0ms)

40% (4.0ms)

50% (5.0ms)

60% (6.0ms)

70% (7.0ms)

80% (8.0ms)

90% (9.0ms)

100% (Static)

MIN PW1 (ms)

MAX PW2 (ms)

Flow Rate

33

81

129

176

224

272

320

367

415

477

0.55

9.41

1MIN PW = pulse width where the injector flow is semi-closed

2MAX PW = pulse width where the injector flow is semi-static

[fjmuurling]

10 hours ago, Gjk said:

The S4s has a different VE from the SE and produces more boost, so would need to be a little more uprated.

This handled by the ECU. The various models have different VE tables programmed in their MEMCAL. (and other tables).

[Gjk]

Thanks Freek. Did you get your PL2-0370 injectors from SJ Sportscars?

 

 

OR can anyone verify that the PL2-0370 are the same as the SJ offering. I tried to read the numbers off the side of the injector in situ but, there’s to much ‘car’ in the way!

[Gjk]

6 hours ago, fjmuurling said:

This handled by the ECU. The various models have different VE tables programmed in their MEMCAL. (and other tables).

I have just checked the S4s parts manual and the primary injector is the same part number as that in the SE manual. As the S4s kicks out 300bhp, if the standard injector is ok with this power level then I guess the RC ones will be fine as well regardless of the uprated claim or not.

[Chillidoggy]

If the original injectors are NLA, then what other choice is there?

I’d love to see a back to back comparison of the original Rochester against the RC on a dyno. 

[Gjk]

Me too Ian. It would even be nice to see a data sheet for the original injectors purely for comparison.

[Chillidoggy]

If the rhetoric is to be believed, a lot of cars would never get to where they were going with the original Rochester’s.

Mine still has its original injectors after 87K miles, but runs OK as far as I can tell. But I do think it would be interesting to investigate the subject with some hard evidence. 

[Gjk]

Hard evidence would be great to have Ian but, I think (like myself) that people only replace their injectors when they find there originals have failed. I don’t think anyone would get their old injectors serviced if they had just forked out for a new set.

If your S4s is running fine, then don’t change anything. If it isn’t broken, don’t fix it! 😎

Considering the reply’s I have had to this thread, I am of the opinion that the RC injectors are more than capable of keeping up with the mild modifications I have in mind for my vehicle.

[MrDangerUS]

RC injectors are well validated by many owners in US and perform very well. I have PL2-0370 primaries and SL4-0190 secondaries for 4 years and they are able to provide enough fuel even for tuned engine.

Since 0190-s have been discontinued, the next closest one is SL4-0205, see below:

https://www.rcfuelinjection.com/Store/c/performance-injectors

"Uprated" is just an advertising semantics.