C5R Experts only...tough questions.

grb · 11-06-2009, 09:29 PM

Before this incredible piece of GM racing history slips off into oblivion there are a few things I'd like to know. If I can't get the answers here, I'll give up. I'm talking about the 427 and not the earlier smaller version.

First, when was the first engine (working prototype?) built? I know Schwartz (?spelling) built the blocks and even the C5R heads but they did not (I asked them) finish the heads. Who did? Katech says it's not them. Who prepared the heads for final use?

The piston? When and who built and/or designed the first ones? Diamond? JE? Maybe Schwartz again?? And is there a difference in the C5R 427 piston and any other GM 4.125" piston? In other words would the piston you would put in a sleeved LSx engine be the same or would the C5R not clear the reluctor ring or whatever? How much difference between the C5R piston and the LS7?

Who was the first piston builder to make them available and when? I think this was in '01 but not sure. Again, is there anything unique to the C5R piston that would make it applicable to only the C5R or is it still an off the shelf piece.

Any other historical facts of links would be appreciated. thanks

XtraCajunSS · 11-06-2009, 10:30 PM

grb,

I have decent knowlege of these engines. If you would like to give me a call at the shop tomorrow, I could probably answer most of your questions.

Shane

grb · 11-06-2009, 10:32 PM

Should have known I could count on a Cajun! Thanks, will do.

Schwanke Engines · 11-11-2009, 10:49 AM

Before this incredible piece of GM racing history slips off into oblivion there are a few things I'd like to know. If I can't get the answers here, I'll give up. I'm talking about the 427 and not the earlier smaller version.

First, when was the first engine (working prototype?) built? I know Schwartz (?spelling) built the blocks and even the C5R heads but they did not (I asked them) finish the heads. Who did? Katech says it's not them. Who prepared the heads for final use?Well, define finish? They were all flow tested and assembled by Katech, but they weren't CNC'd there. I can remember the CNC place now.

The piston? GM design, built by Mahle When and who built and/or designed the first ones? Diamond? JE? Maybe Schwartz again?? And is there a difference in the C5R 427 piston and any other GM 4.125" piston?Completely different compression heights. The C5-R used other than 4" strokes and longer rods. In other words would the piston you would put in a sleeved LSx engine be the same or would the C5R not clear the reluctor ring or whatever?It probably would, but they didn't have internal reluctors, so it would have to be checked. How much difference between the C5R piston and the LS7?That's like comparing a LS1 piston to a LS7

Who was the first piston builder to make them available and when? I think this was in '01 but not sure. Again, is there anything unique to the C5R piston that would make it applicable to only the C5R or is it still an off the shelf piece. Again, Mahle.

Any other historical facts of links would be appreciated. thanks

I guess the guys over at Katech would be able to fill you in on all the old specs, or at least they should be able to if they have time. I know a limited amount from my stay at Katech. I tried to pay attention to all of the race programs, but they were pretty tight lipped with the C5-R.

grb · 11-11-2009, 11:22 AM

I'm not sure that Katech knows the early history of all C5R parts.
By finish I mean, it is my understanding that Schwartz Machine did a lot of preparation to finish the CC to 30 or 38cc or whatever. I don't think this was anything other than a rough cut. In other words when, say, a SCPC got the head it was finished to the extent that it was ready for final porting and polishing. The engine builder would have the combustion chambers "finished" to his size and specs.

In fact, when I asked Katech this question they referred me to Schwartz who said they believed the heads were in some cases sent to a shop somewhere in Michigan or the Detroit area. And some were sent rough CND'd. Not sure what all that means other than Schwartz nor Katech did the final P&P.

It makes sense that Mahle would design the pistons but an apparently confused source told me Diamond built the first C5R pistons. I have no clue what he meant unless he confused the two companies.

I have seen on the Internet where there were some 427 C5Rs running in '01. Just wondering who and when built, tested or ran these engines and when they hit the street. I guess when they hit the street is what I would really like to know.

Thanks for your help!

grb · 11-18-2009, 07:59 PM

Shane...your phone mail box is always full. Any other way to get in touch with you?

XtraCajunSS · 11-18-2009, 08:53 PM

Just call the sales or tech line and have me paged. It is physically impossible for me to answer tech calls AND keep up with my voice mailbox. I have it purposely disabled for that reason.

Thanks,
Shane

MAC4264 · 11-19-2009, 10:41 PM

Lingenfelter built a 427 c-5r motor with cath. heads in late 2000 into early 2001. I can't remeber the exact publication but Chevy High Performance might be it not swearing to it. That motor went into a red sonoma pickup and was turbocharged. That is my earliest account in the street world of the 427 c-5r bottomed end. Then that caused the wave of 427 resleeves, Agostino,MTI etc. You have started other treads on this might I ask why you want this info? Lingenfelter/Lunati were some of the first to pioneer the 4.00 stroke cranks into the LS1, that goes back to 1998, seems like yesterday.

grb · Yesterday, 09:54 AM

History mainly. Look how few people know real facts about the C5R. I've had one, still have some parts and may built another.