Borrowed plate...better?

[BCFAST]

Hey guys! Just a quick question: I borrowed a #8 plate from a buddy, and replaced my #12 tonight after work... will get to drive it in the morning. I know it's supposed to be for an auto, but how will it behave compared to my #12? Thanks in advance!

Brian

 

[Forrest]

OOOOOOOH ... HEHEHEHE ... all I can say is "night & day". I can't wait to hear your post tomorrow Brian. That plate in your 215 pump is 110hp more than the #12, assuming the #12 & #8 is centered. If I remember right, the low end is about the same, but the top end screams. The rear squats down & the front end gets light & off you go. Be careful passing ... the rear bumpers come up LOTS faster. Watch EGT. According to your signature, you've got the HX35, correct?

 

[Don M]

Better watch those high rpm EGT's. That #8 is kinda top heavy on fuel because it is for the little pump.



Don~

 

[BCFAST]

Huh???!! 110hp MORE???!!! I thought the #8 was only a 250hp plate to begin with. True, I have the HX-35... but I have a BHAF feeding an exhaust that graduates from 3"-4"-5". You've got me all excited about going to the office in the morning!!! I'll give a report tomorrow evening.

 

[Don M]

Its more than a 250HP in a 215 pump. You will see a difference



Don~

 

[Forrest]

That's what makes the Auto plates so nice for us 215 pumpers. As the plate # goes down, the amount of fuel goes up. Ck out the table on the link below. You'll see how the #12, 11 & 10 work in the auto pumps. Compare the hp of those & then ck out the #8 ... 10hp more than the #10 in an auto pump. I don't know how much more in our pumps, probably more.



http://www.dieselpage.com/tstpk.htm



Is your probe pre turbo or post turbo? It's important. According to a previous TDR magazine, the HX35 brings about 70 lbs of backpressure to the equation @ 30psi of boost. Boy does this equate to EGT. I was getting around 32psi with the #8 centered. I was measuring 950 or so, post turbo. Moved the probe pre-turbo & I got 1500. The exhaust & BHAF will help.

 

[Don M]

I just moved my probe into the elbow. I did not like the idea of it being in the manifold exhaust stream. it has a spliting effect on the gases as the pass it on the way to the scroll.



Who knows without a dyno, I dont. Its wierd watching the EGT's climb so slow.



Don~

 

[Forrest]

Mine was in the 3" elbow, now gone in favor of the 4" downpipe. If it was still there, I'd like to switch between pre & post to see the difference. Probably not so much with the HX40.

 

[Don M]

I have this HX-40 with the 12 cm housing. It still has the 3"elbow.

I know Im loosing a little on top to gain down low.

Its he!! from stoplight to stoplight. NO lag at all.



Don~