I wonder what it's gonna do through the cast iron manifolds? Did you use a cam with that in mind? I'm not competent on cam selection, or anything else engine related for that matter. LOL. I did see what you used.
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#'s Matching 340 build
- Thread starter RAMM
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RAMM
Well-Known Member
Probably 25-40hp loss through the exhaust manifolds--Yes I chose that cam with the manifolds in mind--take a look at the specs I posted-you should be able to see it. J.Rob
moper
Well-Known Member
I’m just catching up on this thread but a guy who charges $90 around here will starve and close. To get a crank done well here (and I know the best guy around here) is a $300 proposition. That’s not stroke corrected and indexed... that’s cleaned, nagged, turned, and polished. Nothing fancy.
In regard to PRHs comments on streetable power- I’m with him. I consider how often the engine will be in an rpm range for a street car with mild gearing. The car willidle and be under 4K for the vast, VAST majority of its life do power over 5k in not a concern. I think this gets way over-thought by many these days.
moper
Well-Known Member
I loved the cam choice btw. It did well, but I think it will show lower in the chassis with an alternator, water pump, and full exhaust on it. I’d say it will perform a little better than the stock 275 rating, which is really what he wanted from the sound of it.
RAMM
Well-Known Member
Totally agree Moper, I charge $280 CDN for exactly what you describe. The crank in this 340 is .020"/.020" now. Balancing was handled internally of course and that is an additional $380 CDN. J.Rob
RAMM
Well-Known Member
Of course it will be lower in the actual chassis, I bet it will feel much stronger than before. J.Rob
moper
Well-Known Member
I’m sure it will. He’ll be happy, which is the real success. Dyno numbers are just conversation.
MOPAROFFICIAL
Oogliboogli
Needed more cam for that.
My stock x head 280 dur .528 solid .030 340 did 392hp with a self driven water pump,ps, 1 5/8 and through full 2 1/2 pipes.
It's nice to see the small cams Dyno tested/used . I'm not so excited about them as other people are, but I think these other people are the people who would more so use this type of Cam.. and so it's more interesting/gives an idea of their power level.
Thanks for sharing
belmateo
Well-Known Member
I thought the owner wanted a stock rebuild? Where is the carter carb? What are the numbers with the correct carb?
Thanks
Great thread btw
Thanks
Great thread btw
RAMM
Well-Known Member
Patience, I only used the Holley for the critical break in as I know it is a good carb. This afternoon, on goes the Carter and the original distributor. J.Rob
belmateo
Well-Known Member
Thanks, looking forward to those numbers. Maybe I missed it somewhere, what was the static timing set at?
Seth Jones
Well-Known Member
I didn't see it mentioned but what valve spring are you running with that cam? Comp's catalog recommends 622-16 but that part # is for a lash cap LOL!
yellow rose
Overnight Sensation
Hey RAMM, I just looked through this thread and I didn’t see what pistons you ended up with and the CR. I did see you were looking at some JE flattops, but that was all I found.
TIA
TIA
RAMM
Well-Known Member
Timing is at a locked out 35* with the lean burn distributor. J.Rob
RAMM
Well-Known Member
JE piston 310725 was used. Cranking compression is 170psi. J.Rob
RAMM
Well-Known Member
Using a Comp 901-16 Spring / 10* retainer and lock package. It buzzes to 6000 rpm effortlessly. J.Rob
Ever hear of issues with Comps locks/retainers?
RAMM
Well-Known Member
I didn't get to the Carter carb yesterday. I did spend some time perfecting the dyno exhaust system and I installed a new dual wideband O2 sensor system. It works perfectly. What's even more interesting and impressive is I was able to compare the AFR readings from the dual wideband to the Superflow air turbine/fuel turbine calculated AFR readings. The average AFR from the widebands was 12.4 and the average AFR from the Superflow calc'd AFR was 12.3. I'd call that a win all the way around. Where the Superflow system lacks is at idle-you can't trust the AFR reading--with the dual widebands I was able to get the carb dialed to a steady 14..5-14.7 idle AFR on both banks. Exhaust temp readings with a IR gun we within 80 degrees on all tubes as well in the high 700's. I think Mopar knew what they were doing when they designed this intake manifold. I'm impressed. J.Rob
RAMM
Well-Known Member
Nope--just their lifters and noisy lobe profiles. I won't run their XE series anything or use any of their lifters. I do like some of their springs, and cams and I do use them for custom grinds as I like their lobe catalog and quick turnaround. I also like their nitriding option and use it on all solid flat tappet customs. J.Rob
RAMM
Well-Known Member
'69. J.Rob
Nice! Thought it would be a 72 intake. I also have a 71 and from what I have heard, one of the best flowing 340 intakes, but not sure.
NC Engine Builder
Grumpy Old Man
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Excellent thread, I really appreciate the information and results being shared, my hats off to you sir!
Seth Jones
Well-Known Member
[lQUOTE="RAMM, post: 1973147393, member: 17675"]I think Mopar knew what they were doing when they designed this intake manifold. I'm impressed. J.Rob[/QUOTE]
It would be interesting to see if the RPM Air Gap intake would show any hp gains on a build of this type and if those gains would justify the expense over iron intakes.
It would be interesting to see if the RPM Air Gap intake would show any hp gains on a build of this type and if those gains would justify the expense over iron intakes.
if you had a choice which manifold of these 2 would you use for getting the best power and fuel mileage ? fully ported air gap or a stock 1970 iron manifold . interested because i'm building a numbers matching 340 for my car . had enough of the go fast crap , just want a reliable engine for my 100mile+ daily drives .
thanks
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