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Ok guys, I have finally decided my combo for my motor. I have not bought the parts yet, so any suggestions would be great.
thanks.
This will be a head & cam change. The rods, pistons and crank will not be changed for now.
200 Dart iron eagles 64cc with 2.02 & 1.60 valves
comp cam xe282hr10 or xe288hr10
matching comp springs
comp mag roller tip 1.6 rockers.
(the 282 cam with 1.6 will go .544 and .555 lift)
Team-G #7525 street ram single plane intake (2000-6500)
hedman Lt headers
holley 3310 750vs carb
shim head gaskets to bump compression.
I will ge going with a 700r4 with transgo kit and a 3000 stall.
All this will be going on a 383 stroker later on. I will get the cam ground as a small base circle for clearance, but use it in the 350 build for now.
any suggestion would help. Im looking for maybe 400 to 425 hp before going to the 383.
If you need anymore details, just ask
thanks.
__________________ L98, Afr190, Edelbrock RPM airgap, Holley 750 Street HP, Comp XR282HR-12, Crane Gold 1.5 RR's, Hedman LT's, Dynomax Bullets, Th350 Probuilt kit, Jegs 3800 10" converter, Spohn LCARB'S, Richmond 3.73, Hoosier
QTP's
New Best!!!
12.01 at 112.45 mph 1/4 with 1.62 60ft
7.641 at 90.02 mph 1/8
I would not use shim gaskets though; get your block zero-decked to the pistons you use instead, and use the right gaskets. The couple of tenths of a point of CR aren't worth the hassle of replacing the gaskets when (not if) they fail.
Instead of buying the springs and all their hardware after you buy the heads, just specify the springs you want to be installed by Dart when you buy the heads. It will cost you less, and you'll know it's set up right. FYI Dart uses Comp springs on those heads anyway. In fact, you might even want to go ahead and have the light 1.55" springs put on them (not the heavy ones for solid rollers, but rather the ones that are more like the moderate ones for BBC); that way you can run any cam and any rockers you want to, without having to worry about them.
__________________ "So many Mustangs, so little time..."
Which cam would you go with? Do you think I can make the 400-425 hp mark with this combo?
no.
you'll be looking at 318hp @ 6500 and 273 ft lb @ 5500. it's going to be an upper rpm motor, for sure if you stay with the current setup.
your cam should be the XE274H-10 if you want to hit the 400 mark, which it does with your combination showing 403hp@6000 and 408 ft lb @ 4500. it brings the power down in the rpm range, though, which isn't such a bad thing. with a good stall converter, you'll launch hard and solid (with good DRs or slicks).
The XE274H-10 is 230°/236° @.050", .479/490".
The XR282HR-10 is 230°/236° @.050", .510".520".
There's no way in hell the XE274 will make nearly 100 more HP and 125 more ft-lbs than the XR28R. That's patently WRONG on its face. Looks like typical misuse/abuse of Desktop Dyno or some such.
So, let's leave "virtual world" and re-join "real world". I've had both cams myself; in fact, I had them both inthe same motor, where I once took out a XE274, and put in a XR282 with no other changes. So I think I have some insight into how those cams compare.
The roller "acts" like somewhat more cam than the flat, at idle and low RPMs especially. It produces noticeably more torque above about 2500-3000. The 2 cams had similar RPM ranges (they were both done at about 5800 RPM in my motor, a 400) with the roller producing slightly more power overall.
The motor in question was a 400, 186 heads, Performer intake (yuck), 800 CFM Holley spreadbore, TES headers. It did about 274 RWHP and 374 RW ft-lbs with the XE274 on the chassis dyno. That's around 360 HP and 475 ft-lbs at the crank. With a better intake, better heads, and better headers, no doubt it would have done better; but, under the circumstances, namely fitting under the hood, it was what it was. I never had the opportunity to dyno the car with the roller in it.
So all I have to say is, the numbers this guy posted for the XE274 are believeable for the combo you're working with; the numbers he posted for the XR282 don't even come near to passing the smell test. They're bogus. Ignore them.
__________________ "So many Mustangs, so little time..."
I thought both of them were plenty "streetable". The XR282HR was kind of on the edge though. I think it's about all the cam you could stand on the street in a 350. IMO that's the better of the 2 rollers for your combo.
The peak lift numbers don't really tell the full story on the difference between a roller and a flat tappet. A roller will usually open the valves faster, hold them farther open for a longer time, and then close them faster, than a flat with similar "paper" specs. That applies to the XE274 vs the XR282.
__________________ "So many Mustangs, so little time..."
Originally posted by RB83L69 No, no track times....
I thought both of them were plenty "streetable". The XR282HR was kind of on the edge though. I think it's about all the cam you could stand on the street in a 350. IMO that's the better of the 2 rollers for your combo.
The peak lift numbers don't really tell the full story on the difference between a roller and a flat tappet. A roller will usually open the valves faster, hold them farther open for a longer time, and then close them faster, than a flat with similar "paper" specs. That applies to the XE274 vs the XR282.
were you running the xr282hr with 1.6 rr's? What kind of trans were you running? I plan on a 3000 stall, It should help the cam be more streetable.
Originally posted by forums_suck whats your compression going to be at when you bolt on those 64cc heads?
Have ya looked at the pro topline heads?
The stock L98 heads are 64cc, so if I just bolt them on and dont mill the heads or deck the block, then stock compression. My motor is a 92, and in my chiltons it list 9.5 to 1, but the haynes list 9.3 to 1.
And yeah, I have checked out the pro topline heads, and about every other heads on the market. Tough choice, but I can get a great deal on the darts. $750-850 with matching springs for my cam.
I thought about going with the new Dart Iron Eagle Platinum 200 heads. They are suppose to flow 10% more than the regular 200's and have a 5-angle race valve job. Anyone know much about these heads?
im going to be running the xr 288hr in my 383 but dont have it finished yet the block is being machined now.I emailed dart on those platinum heads and they sent me some info on em,the flow the same as the protoplines.That engine easily looks good for 400hp hehe your gonna have fun drivin that