Opinions on my combo please....need input [Archive]

MadMarv

Mar 10th, 05, 12:21 AM

John,

I know I'm not much of a racer, but big red with his 4060lb car got 116mph from his UDHR4. I got 113.8mph with that cam in a 4020lb car with rectangle heads. I'm also not very good at tuning, and the cam never really got a full chance to get really pushed, I had another problem that required a cam change and UD was closed shop at the time when I needed a new one.
The cam is an UDHR4, 296/296 233/233 .621/.621 (might be .625, I *always get that wrong!!). Mean sound. Great power. The engine problem I had was not cam related, but I needed to refresh the cam during the rebuild. 15k miles 'set it and forget it.' If I can find my photo album (I wanted to scan everyone a pic of my car when I first got it) I have my 1st timeslip ever in there.
I know it seems I rec. this cam to everyone that wants a performing hyd roller in a 454-468, but it seems easy on parts and makes great power. I don't know what heads big red uses, but I used too-huge dart 320cc rectangular runner ports, 750dp, RPM intake, 2" headers (big also) and posted 113.8 w/ a 12.70 on my first time drag racing ever with a 2.25 60' on p245 26" tall *street* bfg's. There was alot more left in this cam from someone who could do a proper tune and test method.
So unless harold has something else to say (which I'm sure he very well may!), I think this is a great cam. I'd use it again in a heartbeat.
I also run a carter 172. Was running a carter 120 w/ the UDHR4. BTW, the HR4 times/mph was with 3.31's. All other cams used 3.90's. I have yet to unleash the potential of my SR, but I am expecting about 118-119 this summer. I know its there, despite naysayings I've heard.
I am also a .030 over 454, forged SRPs, eagle rods, roller rockers.
With the HR4 I would put you at 500hp min @ 112+ with tuning. Of course there is no guarantee, and I am not a real racer. also take to note big red's car and mine as well are both very porky. Last time I was on a track scale was 4008 w/ my ET streets (small ones), last time w/ track scale w/ stree tires (big) was 4035, both at about 1/2 tank of gas, me, all steel etc.
So that is my vote. why you'd listen I don't know why.
I am pretty sure my cam/heads currently are a bit on the big side. That being said, my SR swap was worth 35hp according to MPH (from the second cam, not the UD, from the UD the gain was less). The UDHR4 made more torque, but not nesc. more hp, across the rpm range to 5800, where both hyd rollers began to fall off pretty quick.
Its my *guess* with this cam and your combo you should have a torque monster from off idle to 5800 with no fancy tricks.
I hope this is of some help, and I really look forward to hearing about your results, no matter what cam.
In retrospect, I believe a well-selected hyd roller is a great street/strip very high performance, but not all out, camshaft.

I used comp lifters with both hyd cams with no worries. With the solid I am using isky's.
Both the hyd rollers used steel retainers and the same ferrea SS valves.

BTW, harolds UDHR4 out torqued and out performed a comp HR that was 286/286 230/230 .639/.639, but when I was running harolds cam the motor was 9.6:1. With the comp cam it was 10.14:1, and still is even with the SR (yeah I know..).
So it doesn't have to be a harold cam, but there are two pork rind cars on this site that have run respectable (at least two anyway) on this site.
IF I were to go back to a hyd roller, I would either use this one again or see if harold has something else that is about 238 to 242 @ .050, about .620 lift, gentle ramps for long life. I'm not out to win any trophy's.

Sorry this was so long! I hope you will have fun. The *only* true variable here I see is the fact you had a manual trans. IIRC harolds HR4 was on a 112 lobe sep, the CC was on a 110. SR on a 112.

so in essence, with limited tuning & an unrelated problem at 15k miles on the motor, I had netted a 12.70 @ 113.8, 2.25 60', 4020lb, 3.31 gear TH400, 2400rpm J&W converter. respectable performance.
The rest of the engine/car
all steel, all interior, spare tire.
2 bolt GM ls5 block
.030 over, forged SRPs
GM ls5 forged crank
eagle +.250 rods
dart 320cc rect port heads, out of box
unsure of springs in the UD build
GM heat tray in valley
stock GM oil pain w/ screen
carter 172
holley 750DP w/850 base, I have the jet #'s somewhere if you might need them, doubt it. (your 850 should be fine, I got 10mpg with this combo)
MSD 6al, pro billet, 5" reusable element air cleaner
2" hookers, 3" exhaust (was true dual at this time), 20" case dynomax turbo mufflers.
John with this combo I'd say over 500hp @ over 112 as a guess. I'm just detailing this combo because I've used it, not because I know about stuff. I was close to 114 myself, and I think with a better 60' than the 2.25 or someone with a clue tuning it, I had potential for alot more, just like I am almost dead set sure the cam I have now will get me to 119.

good luck!

matt