ShaunSG

iTrader: (1)

Considering Scorke's questions, I would not assume we're all aware of the obvious. No offense Scorke. There's nothing wrong with being new to something. We all are new to almost everything.

I submit that the observation is inaccurate.

In one day a flow limit can be found, whereas a typical street car engine service life in miles (both pre and post mods) takes much longer (months or years) to verify, and at the same time is tested with little to no control. It is here that subjectivity clouds the issue - which is why it is necessary to look to very defined and very objective arenas to make the best comparisons possible.

Ted B

iTrader: (6)

Well, I 'submit' that it is accurate enough for me to form an opinon, and we'll just have to agreee to leave it at that. Cheers.

trinydex

iTrader: (12)

is that so......... guess there doesn't need to be an entire subject of physics called newtonian mechanics to describe it then huh?

David Buschur

iTrader: (53)

Couple of things.

Yes, I did do my math in inches when I figured out the displacements. The quote that was posted was figuring standard bore, if it was figured using overbored I would have stated that.

I build a LOT of engines. I honestly can't imagine any other shop building more engines than we do, 4g63's. I suppose it's possible but we build a lot of them.

I have tried many different combinations over the 17 years of building these engines and I have seen many tried.

The full 2.4 engine I have not seen produce any good results yet. Let me rephrase that, I have seen good results but I have no seen GREAT results. Some of the guys that have been brought up that built 2.4 liter engines I know personally and can tell you they were nothing but problems and come apart for different reasons quite often.

The 2.25 liter engine we build (stroker 2 liter) has worked out very good. I was dead against trying them again until I actually got with a tech at J&E and had a piston designed that was different than I designed quite awhile back. This was the key to the success of the strokers we are building now. We have had them to 9975 rpm. We have a few cars crossing the finish lines at 9,000+ rpm. The short gearing in the EVO makes high rpm's necessary with traps speeds over 140 mph.

Dyno numbers mean nothing, the longer I am in this business the more I realize it's all smoke and mirrors. When we had our Dynojet we made huge numbers and ran times that backed them up. We were called liars and such as our numbers were so high. Now we have an AWD MD that is completely calibrated by the factory and it reads SUPER LOW numbers. Now that our dyno reads low numbers other people like to exaggerate the fact that they dyno'd on a MD and made some huge number. Problem is the MD is EXTREMELY easy to change so it will read high numbers, so that makes then worthless again. Case in point, our 2.25 liter engine made 530 whp on our dyno, sounds low compared to some of the 2.4 liters you read about. Difference is our car ran 10.1 at 141 mph. Al's car made 580 on our dyno with our stroker, he ran 10.0 at 143 mph. Matt's car made 580 on our dyno with our stroker and ran 10.1 at 144 mph ON a REAL street radial Nitto 555, not drag radials. All three of these cars have been rev'd very high and have had no engine problems.

I have seen destroked 2.4's, they come out to around 2.1 liter. Nothing good came of it and it was in a top DSM when tested.

I built the engine in John Shepherd's car and I can tell you that it is for sure 100% truth a .020 overbored 2 liter engine. The car is constantly at 10,000 rpm and crosses the finish line at close to 10,500 rpm. The AWD Talon ran 7.97 at 179 mph.

We just switched our black EVO drag car back to a 2 liter, come spring we are going to need the RPM also as we hope to be running some crazy fast times

One last thing. I don't want to give any engine building information away but doing a stroker 2 liter doesn't put the rings into any harm Keith. The ring set we use in our stroker is the exact same ring set that is in John's car, exact. We also did not have to move them up any closer than normal to the top. SSHHH, it's all secret

David Buschur
www.buschurracing.com

ShaunSG

iTrader: (1)

David, what gearboxes were your 2.25L, Al, Matt, and John's car running?

Were any of them running nitrous? If so, which of them?

Which of them races in NHRA or IHRA classes at any time?

With any majorly reworked engine, there are more often than not systems issues.
The concept of weight breaks and valve area and necessity of high RPM for 1/4 mile drag racing, given gear limitations has been explained before.

David Buschur

iTrader: (53)

Stock gear boxes in all of the cars.

No nitrous ran on the passes I mentioned. AL has run nitrous but the 10.0 wasn't on the bottle.

All of them are legal for NHRA and IHRA but Al is the only one that has run a real NHRA sanctioned event.

David Buschur
www.buschurracing.com

ShaunSG

iTrader: (1)

I see. So then.. yes.. they are in fact gear limited and so the 2.0 rev range suits them. If they could run custom gearing I am sure the strokers would dominate.

The John Shepherd run you mention is listed on the following page as being a nitrous run. Is it wrong? http://www.dsmtimes.org/times.php?Page=1

Thanks for the information.

trinydex

iTrader: (12)

bump this to get rod ratios for the 2.0 2.4 2.3 and 2.2s

David Buschur

iTrader: (53)

Wow trinydex, you brought one back from the dead! haha

Since you did, I will put in a plug here I have a 2.4 block/crank for anyone wanting one. We don't build them and I got this shipped to me as a core. PM me if interested.

Rod ratio is easy to figure out.

trinydex

iTrader: (12)

yeah nix the request i figured it out hahaha

german_evoVII

Hello to all here,
I have to bring that tread back.
I currently having an Customer here in Germany, which has an RNR 2.4L Engine in his Evo. The car was assembled by Turbotrix, and brought over to Germany ( Customer is Army / Airforce Member stationed here )
Since the Engine has unusual noise, i did an Compression test with the Engine.

Numbers were:
Number 1: 203Psi
Number 2: 191Psi
Number 3: 194Psi
Number 4: 90Psi

So, Number 4 ist out of spec. Before we disassemble the Engine, i want to order an Ringset for these Engine. ( to shorten the downtime since delivery to Germany can take some time )
Looking with an Camera inside the combustion chamber doesnt show any damage to the Piston Itself, also oiling the Ring from the top doesnt improve Number 4, so it can be broken?

What i know is:

RNR Built 2.4 Liter 4g64 Engine
maybe .20 over ( i believe they advertised it in that way, so 1th over )
Wiseco Pistons for the 2.4 L

Since RNR is out of business, did anyone know what type of rings will be needed for these Pistons.
There are two sets listed 1mm, 1.2mm and 2.8mm ( 8650XX )
and the more or less standart 1.2, 1.5, and 3mm set.

Maybe anyone of the EX - Employees / Owners/ Builders or an other Customer of them has the needed Information.

Many Thanks in advance
Steffen Thormann
Just - Solutions
Germany

slicedbreadno2

iTrader: (9)

Some pretty interesting information.